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[Transplacental passage of cells from mother to fetus: experimental approach and initial results in the rat].
|
The consequences of transfusion across the placenta of maternal cells to fetuses, supposed to elicit a Graft-Versus-Host-Reaction, are poorly investigated; the injection of pregnant rat whole blood cells to its own fetuses is proposed here as a convenient experimental model to improve the understanding of these consequences; indeed this technic is reliable as well as easy enough to carry out experiments on large samples. Preliminary results indicate that the injection is often followed by a runting disease, a thymic atrophy and a liver hypertrophy; splenomegaly does not occur. On the histologic level, the main features are as follows 1) modification of central lymphoïd organs, 2) blastic and/or granulocytic infiltrates of several other organs, namely the liver, the adrenal cortex and the thyroïd gland.
| 45,257
|
Microspectrofluorometric studies on the formaldehyde-induced reaction product of 5-hydroxytryptamine.
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A new model incorporating Sephadex G-25 as an inert carrier has been developed for studying the reaction between biogenic amines and formaldehyde vapour. Both the fluorescence yield and the spectral characteristics of the 5-HT formaldehyde reaction product are influenced appreciably by the relative humidity at which paraformaldehyde is equilibrated, the duration of the reaction, the glycine concentration and pH of the suspending solution and the duration of exposure to ultraviolet light. It is concluded that care should be exercised in attempting to identify or quantify 5-HT on the basis of microspectrofluorometric analysis.
| 45,274
|
[Sympathetic mediation of induced and spontaneous activity of the pelvis-ureter in vitro].
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The spontaneous activity of guinea-pig renal pelvis-ureter is regulated by the adrenergic system. Spontaneous rhythmic contractions, and contractions induced by Noradrenaline are inhibited by Dihidroergotamine and Phentolamine. Alpha-adrenergic blocking agents block also contractions induced by histamine, angiotensin and barium chloride, but not contractions induced by electric stimulation. The Authors suggest an hypothetical model for the activation of the adrenergic receptor: Noradrenaline (NE) recognition sites are activated only by NE, whereas complementary sites can be activated by NE or other agonists. Both sites are blocked by alpha-adrenergic blocking agents.
| 45,305
|
[Postvaccinal encephalitis in adult. A case with anatomo-clinical report (author's transl)].
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While post-vaccinal encephalitis in children is unfortunately well known, its occurrence in adults is rather exceptional. The calendar of a poly vaccination situated so close to each other, most probably account for such an evolution. The case reported concerns a man of 27 years who presented 10 days after a polyvaccination (7 vaccines in 2 months) altered consciousness, epileptic fits, right hemiplegia, vegetative dysfunctions and meningeal status. Evolutionary clinical course led to death in 21 days. Neuropathological findings showed lymphocytic infiltrates in the cortex and basal ganglia, congestive aspect with petechial areas in the white matter and inflammatory meningeal infiltrates. All viral investigations both in the blood, brain and cerebrospinal fluid remained negative. Post-vaccinal encephalitis is reviewed. Vaccination cannot be condemned, but in case of polyvaccination lapse of time in between vaccines should be longer so as to prevent such exceptional evolution and fatal course.
| 45,321
|
[The development of psychopharmacotherapy].
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Based on experiences during the longterm treatment with psychotropic drugs the following subjects are discussed: extrapyramidal side effects of neuroleptic drugs, cardiovascular side effects of antidepressants, side effects of Lithium, interactions with other medications, influence on laboratory tests and also the psychopharmacological treatment during pregnancy.
| 45,344
|
Viability of some Salmonella strains in Algerian eggs.
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Whole-egg and egg-white were inoculated with S. typhi murium, S. dublin, S. oranienburg and S. oslo separately and were stored at - 1 degrees C, + 4 degrees C and 26-28 degrees C. pH value was determined every day as well as the survival of the different inoculated Salmonella strains till the end of the experiment. Stored at - 1 degrees C in case of whole-egg, egg-yolk and egg-white, pH values were 7.0, 6.0 and 7.0 while the maximum values were 8.5, 8.0 and 9.0 respectively. The shortest survival period for Salmonella strains was 101 days in whole-egg, 103 days in egg-yolk and 36 days in egg-white, while the longest period was 114, 123 and 59 days respectively. The minimum pH values of whole-egg, egg-yolk and egg-white stored at + 4 degrees C were 6.5, 6.0 and 7.0 while the maximum values were 8.5, 8.5 and 10.0 respectively, 55, 66 and 30 days were the shortest survival periods for Salmonella strains inoculated in whole-egg, egg-yolk and egg-white while the maximum periods were 81, 80 and 67 days. The minimum pH values of whole-egg, egg-yolk and egg-white held at room-temperature, were 6.0, 6.0 and 7.5 while the maxima were 8.5, 8.5 and 10.0 respectively. The minimum survival period of the Salmonella strains inoculated in whole-egg, egg-yolk and egg-white was 52, 41 and 21 days, while the maximum periods were 63, 52 and 37 days respectively.
| 45,429
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Isolation, cryopreservation, and autotransplantation of human stem cells.
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We have used cryopreserved autologous hematopoietic cells to repopulate bone marrow of patients receiving intensive chemotherapy and radiation. We employed the technique of density step centrifugation to concentrate stem cells from whole bone marrow. The concentrate of cells was frozen in vials using dimethyl sulphoxide (DMSO) as a cryo-protective agent and was stored in the vapor phase of liquid nitrogen. Test vials were thawed and assayed for myeloid stem cells (CFU-C) to determine the potential of the larger marrow aliquot. These test values were compared to the recovery of cells and CFU-C when the marrow was used for autotransplantation. The return of hematopoietic function after autotransplantation was evaluated and correlated with the dosage of cells and CFU-C infused.
| 45,456
|
Neuroendocrine modulation of calcitonin and parathyroid hormone in man.
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Recent evidence suggests that of calcitonin (CT) and parathyroid hormone (PTH) is controlled by factors other than the ambient serum calcium concentration. We studied the effects of infusions of four neuroendocrine modulators upon CT and PTH levels: isoproterenol (beta-adrenergic agonist), methoxamine (alpha adrenergic agonist), prostaglandin E2, and somatostatin. Isoproterenol was a consistent secretagogue for both hormones. Maximal CT increments during isoproterenol infusion in normal subjects were 13 +/- 2 pg/ml (mean +/- SEM, n = 6, P less than 0.001; basal, 26 +/- 5). Maximal increments in PTH were 113 +/- 22 pg/ml (P less than 0.01, n = 6; basal, 430 +/- 11). Infusions of methoxamine increased CT by 13 +/- 5 pg/ml (n = 5, P less than 0.05; basal, 43 +/- 13), but had no effect on PTH. The means of the maximal CT increments during isoproterenol (21 +/- 8 pg/ml) and methoxamine infusion (28 +/- 11 pg/ml) were not statistically different from those achieved by acute elevations of serum calcium levels within the physiological range (41 +/- 23 pg/ml). Infusions of somatostatin and prostaglandin E2 had no or only transient effects on basal or stimulated CT or PTH levels. Our data suggest that adrenergic input modulates CT and PTH secretion in humans independently of changes in serum calcium.
| 45,460
|
Failure of alpha-methyltyrosine to inhibit peripheral triiodothyronine formation.
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To determine if the adrenergic nervous system, and specifically tyrosine hydroxylase, plays a role in the extrathyroidal conversion of T4 to T3, normal male volunteers were treated with T4 and subsequently with T4 and alpha-methyl-p-tyrosine (alpha-MPT), an inhibitor of tyrosine hydroxylase, for 2 weeks. The mean serum T4 and T3 concentrations increased during T4 administration and remained at the same levels during combined T4 and alpha-MPT administration. Urinary vanillylmandelic acid excretion declined significantly during alpha-MPT administration. These results do not support the hypothesis that tyrosine hydroxylase is involved in extrathyroidal T3 production.
| 45,464
|
The arteriographic manifestations of Takayasu's arteritis in children.
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Eighteen cases of Takayasu's arteritis in children under 14 years of age are described, emphasising the arteriographic features and noting differences with other series. Renal artery stenosis resulting in renal hypertension was the most significant finding but widespread involvement of the aorta and its main branches with predominantly stenotic lesions was also found. Total aortography is mandatory in these cases as without it the correct diagnosis cannot be made.
| 45,479
|
Mandibular fractures. II. A follow-up study of 229 patients.
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During the period 1964-73, 286 patients were treated for mandibular fractures. 229 patients (80%) attended the follow-up examination. The length of observation was from 1 to 9 years. The treatment and the follow-up evaluations in the 229 patients are described. Early fracture treatment has been the objective, also in patients who have undergone severe cerebral traumas. Antibiotic prophylaxis was implemented in cases of compound fractures. Preservation of teeth and tooth buds in the line of fracture was attempted. Clinical infection occurred in 0.4% of the patients. At the follow-up examination 1 patient presented with a fracture displacement outside the condylar process. Neither malocclusion nor pseudarthrosis following fracture or after treatment were seen. Permanent sensory disturbances in the innervation area of the mental nerve following fracture occurred in 8%. Radiological examination of the teeth in the line of fracture revealed unnoticed apical bone lesions in 17% of 118 patients. In a further 23% there was a negative response to the vitality test. Follow-up control of mandibular fractures is advised at 12 to 18 months after treatment.
| 45,484
|
Two pools of glycogen in Saccharomyces.
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The effect of different extraction procedures on the yields of water-soluble and water-insoluble glycogen fractions from a number of Saccharomyces strains was studied by using a specific method for glycogen determination. The similarity of the yields obtained by the different procedures showed that neither form of glycogen is an artifact, and variations in the relative amounts of glycogen in the two fractions during cell growth and in different yeast strains suggest that they represent different pools of storage material with specific roles in cell development and differentiation. A proportion of the water-insoluble glycogen fraction, solubilized by mechanical agitation, was shown to be strongly associated with a beta-glucan-like polysaccharide that may be a cell wall component.
| 45,487
|
The value of pulsus paradoxus in assessing the child with status asthmaticus.
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The presence of pulsus paradoxus (PP) in 13 episodes of status asthmaticus in 12 children, ages 13 months to 15 years, was compared sequentially to a clinical score, peak expiratory flow rate (PEFR), heart rate, arterialized capillary pH, carbon dioxide pressure (PCO2), and the ratio of inspired oxygen to oxygen pressure (FIO2)/PO2) during the first 48 hours following admission. There was a significant correlation (P less than .01) between the presence of a PP (greater than or equal to 5 mm Hg) and the clinical score (r = .79), PEFR (r = .55), and heart rate (r = .49). This was particularly striking when the PP was greater than or equal to 20 mm Hg. There was no significant correlation between the mean PP and the PCO2 or FIO2/PO2 ratio. However, a mean PCO2 exceeding 40 mm Hg was associated with a highly significant (P less than .005) difference in mean PP (22.2 mm Hg) compared to the mean PP (12.2 mm Hg) when the PCO2 was below 40 mm Hg. Although the PP technique can easily be learned by physician and nursing personnel, there are potential problems. The difficulties in children are compared to those in adults. The PP is a valuable clinical tool in assessing the severity of airway obstruction in status asthmaticus. The presence of a PP, particularly greater than 20 mm Hg, is associated with moderate to severe airway obstruction. In conjunction with the overall clinical status of the patient and frequent blood gas determinations, the PP allows for better evaluation of the patient with status asthmaticus.
| 45,490
|
Assessment of clinical laboratory techniques in the measurement of oxygen saturation in whole blood.
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The accuracy and advantages of determining percentage of hemoglobin oxygen saturation of whole blood by advanced instruments of oximetry, gas chromatography, and the computation of oxygen saturation from pO2 and pH data are compared with the Van Slyke-Neill manometric method. It was found that oximetry is extremely fast, less expensive, and more accurate than in the past, the apparatus requires little training to operate and has diminutive service maintenance. The gas chromatograph proved to be highly accurate and could serve as a standard calibration check method in place of the more time-consuming Van Slyke-Neill apparatus for oximetry and pO2 and pH electrode instrumentation. Computation of O2 saturation from pO2 and pH data also proved to be accurate, confirming that this method is more useful during cardiac surgery because it can provide additional acid-base information. In the low oxygen saturation range (less than 60%), all three methods proved to be of similar sensitivity.
| 45,493
|
Purification and properties of beta-lactamase from Bacteroides fragilis.
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Beta-Lactamase activity was detected either biologically or using the chromogenic cephalosporin 87/312 in 20 clinical isolates of Bacteroides fragilis with penicillin G minimal inhibitory concentrations of 10 to 100 micrograms/ml. Strain AM78 (minimal inhibitory concentration, greater than 1,000 micrograms/ml) was used to optimize the conditions for production, assay, and storage of the enzyme. The enzymes are cell associated, with less than 1% of activity being found in culture fluids during growth, and can be released from the cell surface by modified osmotic shock procedure. This procedure causes concomitant release of cyclic phosphodiesterase activity. Substrate profiles and the effects of inhibitors were determined for enzymes partially purified by osmotic shock release and gel filtration. The enzymes are cephalosporinases with some penicillinase activity and are inhibited by p-chloromercuribenzoate, cloxacillin, and carbenicillin. The molecular weight, as determined by gel filtration, is 29,000 to 31,000. A method for the purification of the beta-lactamase from strain AM78 is described: the specific activity of the purified enzyme was 3,424 U/mg, about 3,000-fold that of the crude, cell-associated enzyme.
| 45,494
|
Role of a radiologic technologist trained as a physician assistant in diagnostic radiology.
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This article describes a program for physican assistants in diagnostic radiology at the University of Kentucky, currently the only one in the country. Available only to graduates of AMA-approved radiologic technology programs who have two years of field experience, it consists of two additional years of intensive education in many aspects of radiological medicine.
| 45,504
|
A perspective: the external degree as a viable educational model in nursing.
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The external degree is not new in higher education. However it has not as yet been fully developed. Its usefulness has been demonstrated at the undergraduate level where students are able to move up the career ladder to licensure or degree. It appears to be a viable alternative for nurses seeking educations at the masters level also. By definition it is a nontraditional method of delivery. Nursing as a profession abounds with nontraditional potential students. The author has made no attempt to sell the "external degree" to nursing educators. The focus has been on heightening the awareness of readers to this rapidly developing change in higher education. In a time when concepts such as recurrent education, part-time students, credit for life and work experience, meaningful education and the adult student are much discussed in higher education, nursing educators should not be left behind. The external degree, modified or unmodified may well be the mechanism needed for providing quality education for nurses with varying backgrounds.
| 45,509
|
Head-to-head association in bovine spermatozoa induced by catecholamines.
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Noradrenaline, adrenaline, and isoproterenol induce head-to-head association in bovine spermatozoa in a Tris-HCl-buffered medium. Noradrenaline was the most and isoproterenol the least efficient. This effect was stimulated by Ca2+, Mg2+ and Mn2+, Ca2+ being more efficient than the other two ions. At 2 X 10(-6) M Ca2+, oxidation products of adrenaline dissociated spermatozoa associated by washing; at 2 X 10(-5) M Ca2+, the dissociating effect was transformed into association. The induction of association by adrenaline was blocked by both alpha- and beta-adrenergic blockers at low concentrations (2 X 10(-7) M). Both cAMP and dibutyryl substituted cAMP (db-cAMP) induced association in the Tris-buffered medium at 2 X 10(-6) M Ca2+. Further increase in association was brought about by increasing the Ca2+ concentration to 2 X 10(-5) M. Prolongation of the treatment with cAMP increased association. When combined with cAMP under the same conditions as used in the combination with adrenaline, L-propranolol did not inhibit association induced by cAMP. In an identical experiment, performed in Tyrode solution, L-propranolol inhibited association induced by cAMP. At 2 X 10(-5) M, theophylline, caffeine, and papaverine induced association in the presence of 2 X 10(-5) M Ca2+. The results are compatible with the hypothesis that catecholamines act via receptors and formation of cAMP.
| 45,520
|
Glutamine synthetase in kidneys of monkey and man.
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1. The synthesis of gamma-glutamylhydroxamate from glutamate and hydroxylamine has been utilized as an approximation of glutamine synthetase activity in kidneys of rabbit, rat, dog, monkey and man. 2. Kidneys of rabbit contain glutamine synthetase in high activity; those of rat, in intermediate activity; and those of dog, monkey and man, in negligible activity. 3. No more enzyme is present in kidneys of the latter two species than in those of the dog, in which the enzyme is generally considered to be absent.
| 45,541
|
Preliminary characterization of the delta-9 desaturase of Tetrahymena pyriformis W.
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1. In vitro assay conditions have been defined for measurement of delta 9 desaturase activity in Tetrahymena pyriformis W. 2. The reaction depends on the presence of oxygen and a reduced pyridine nucleotide cofactor. FAD supports a low level of enzymatic activity. 3. Both stearyl-CoA and palmityl-CoA are acceptable substrates. Oleate formation is maximal at 30 degrees C. 4. Delta-9 desaturase activity appears to be localized in the microsomal fraction. Delta-6 and/or delta 12 desaturase activities have also been observed. 5. When the specificity of the delta 9 desaturase towards stearyl-CoA and palmityl-CoA was observed at 30 and 16 degrees C it was found that lowering the assay temperature did not affect specificity. Stearyl-CoA was more readily desaturated at both temperatures. 6. Exogenous oleyl-CoA and diisopropylfluorophosphate had little effect on delta 9 desaturase activity. However, cyanide strongly inhibited desaturation and a sensitivity to sulfhydryl-binding reagents has also been demonstrated.
| 45,543
|
Characteristics of delta 1-pyrroline-5-carboxylate reductase from Drosophila melanogaster.
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1. Biochemical properties of delta 1-pyrroline-5-carboxylate reductase from d. melanogaster have been investigated. 2. The enzyme is stable below 4 degrees C. 3. the pH optimum of the enzyme is 5.7. It is rapidly inactivated below pH 5.4. 4. The Km values for NADPH and delta 1-pyrroline-5-carboxylate are 1.6 x 10-5 and 2.5 x 10-6 M, respectively. 5. the estimated molecular weight of the enzyme is 225,000. 6. the enzyme is weakly inhibited by L-proline (Ki = 0.12 M).
| 45,549
|
Alanine aminopeptidase activity and autolysis in the tails of Rana catesbeiana larvae during metamorphosis.
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1. Alanine aminopeptidase activity and autolysis increase concomitantly in tail tissue of Rana catesbeiana tadpoles during metamorphosis. 2. significant increases first appear at Taylor and Kollros state XX and coincide with the beginning of tail regression as determined by the tail wt body wt ration. 3. The results suggest a role of alanine aminopeptidase in the mechanism of tail resorption.
| 45,550
|
Biochemical studies of supernatant malate dehydrogenase allozymes in Drosophila melanogaster.
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1. A biochemical comparison was made among cytoplasmic malate dehydrogenase allozymic variants from Drosophila melanogaster. Experiments were carried out on enzyme extracted from six different genotypes: three homozygotes and their respective heterozygotes. 2. The allozyme forms (MDH A, MDH B, MDH C) were indistinguishable in terms of NAD and L-malate optima, while they are distinguishable in terms of NADH and OAA saturation conditions. Activities were inhibited at concentrations greater than 0.36 and 0.40 mM NADH for BB and AA, CC, respectively, while in relation to OAA inhibition was observed at concentrations higher than 3 or 6 mM for the AA, CC and BB, respectively. 3. differences among genotypes were also observed in thermal stability: Km values for OAA, L-malate, NADH and NAD: and pG optima. 4. A simple method is presented for the separation of the cytoplasmic from the mitochondrial malate dehydrogenase.
| 45,555
|
Metabolic changes in Crithidia fasciculata accompanying physiological adaptation to growth in the presence of carbonyl cyanide m-chlorophenylhydrazone.
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1. Crithidia fasciculata adapted to growth in the presence of 10(-5) M carbonyl cyanide m-chlorophenylhydrazone (CCCP), an uncoupler of oxidative phosphorylation, maintained adenosine phosphate pools and an adenylate energy charge comparable to those of control cells. 2. CCCP-adapted cells in the presence of the uncoupler respire endogenous substrate at a greater rate than control cells and this effect of CCCP appears readily reversible. 3. CCCP-treated, adapted cells, supporting high endogenous respiration rates, were not responsive to added substrates which significantly stimulated the oxygen utilization of normal C. fasciculata. 4. CCCP-adapted cells, provided with [U-14C]-labeled proline, utilize this substrate at 67% the rate of control cells, but divide the isotopic label between CO2 and protein in a ratio identical to that of normal cells. 5. The transport of alanine and proline by adapted C. fasciculata was severely impaired, while the transport of tyrosine and leucine was unaffected.
| 45,556
|
Perspectives in chemotherapy of schizophrenic psychoses.
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1. The treatment of schizophrenic symptoms has not the same efficacy in acute and chronic phases of the disease and on the various target symptoms of schizophrenia. 2. The ideal antipsychotic drug might have different properties, sometimes contradictory, to be effective both on paranoid and hebephrenic symptoms which seem to be a mirror image of the same disorder. 3. Basic perspectives in the chemotherapy of schizophrenic psychoses must be founded on better methodological considerations in clinical trials, on a better use of antipsychotic drugs with the help of pharmacokinetic data and computerized EEG and also on new neurochemical findings. 4. Recent data on the mode of action of neuroleptics open up new therapeutic classes of drugs. Such are GABA-like drugs and, more recently, beta-blockers.
| 45,563
|
AHR-6646: a new, long-acting neuroleptic.
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1. AHR-6646 blocked d-amphetamine lethality in mice under aggregated conditions when the pretreatment interval was between one hour and seven days. 2. Conditioned avoidance responding in mice and cats was suppressed by AHR-6646 in doses that did not impair escape behavior. The duration of this effect was markedly prolonged. 3. AHR-6646 produced catalepsy in rats. The onset of this effect was delayed and the duration was prolonged when compared with that of chlorpromazine. 4. Apomorphine-induced pivoting in mice with unilateral lesions of the caudate nucleus was suppressed by AHR-6646. 5. AHR-6646 was a potent antiemetic agent in dogs, with a delayed onset and prolonged duration of action.
| 45,570
|
Teichoic acids of group D streptococci with special reference to strains from pig meningitis (Streptococcus suis).
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Immunoelectrophoresis revealed in phenol extracts from S. faecalis and S. faecium a mixture of free and lipid-bound teichoic acids, both reactive with Group D antisera. In phenol extracts from S. suis only lipid-bound teichoic acid, also reactive with Group D antiserum, was seen. This difference probably accounts for the low yield of Group D antigen from S. suis as compared with S. faecalis and S. faecium when heating at pH 2 is used for extraction. When phenol is used good yields are obtained from S. suis as well as from S. faecalis and S. faecium. Lipoteichoic acids from S. faecalis and S. faecium have a backbone structure the same as or similar to that of Group A streptococcal teichoic acid. Lipoteichoic acid from S. suis has a structure differing from that of S. faecalis and S. faecium, e.g., possibly in the attachment of its glucosyl substituents. Precipitation reactions between S. suis lipoteichoic acid and Group D antisera were specifically inhibited by glucose. Reactions between S. bovis phenol extracts and some Group D antisera were also specifically inhibited by glucose, but extracts from S. faecalis and S. faecium were not. This may indicate a monosaccharide glucosyl substituent in teichoic acid from S. suis and S. bovis instead of the di- or trisaccharide previously postulated as the glucosyl substituent in the teichoic acid of S. faecalis.
| 45,589
|
The homogeneity of the faecal coliform flora of normal school-girls, characterized by serological and biochemical properties.
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The homogeneity of fecal coliform flora in 52 schoolgirls was studied by serotyping and biotyping 10 randomly selected colonies in one fecal culture from each child. Ninety-eight clones were identified and of these 52 were dominant and 46 were minor strains. The probability of including at least one isolate of the dominant clone in a small random sample of colonies was calculated to be 86% for one colony, 94% for 2, 97% for 3, 99% for 4, and 99.3% for 5 randomly selected colonies.
| 45,599
|
A comparison of staphylococcal nasal carrier rates in Germany and Poland.
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Frequencies of different staphylococcal nasal carrier classes were studied in groups of students of nursing and of laboratory personnel in Cologne, West Germany, and in Krakow, Poland, by six consecutive samplings of their nasal vestibules. The general number of persistent carriers of S. aureus appeared to be lower than in previous studies, paralleling the diminished numbers of staphylococcal infections in populations. Differences in numbers of persistent carriers between the Cologne and Krakow groups were probably related to the incidence and types of S. aureus in the environment.
| 45,603
|
Metabolism of oestradiol by human mammary tumour 800 x g supernatants pretreated with dihydrolipoic acid.
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Incubation of human mammary tumour 800 x g supernatants with [3H]oestradiol after preincubation for 10 min at 0 degrees C with 10 mM dihydrolipoic acid resulted in metabolism of oestradiol. This was noted in 12 malignant tumours, 8 of which contained measurable oestrogen receptor levels. In 2 benign tumours lacking measurable levels of receptor, dihydrolipoic acid pretreatment had no effect. This metabolism was further stimulated by pretreatment with NAD, NADP and the anti-oestrogen Tamoxifen (ICI 46,474). When incubations were carried out in an O2 atmosphere using oxygenated buffers, the effect was suppressed.
| 45,733
|
Effect of cardiotonic and vasoactive drugs on transmural flow distribution and ventricular volume in the fibrillating heart on cardiopulmonary bypass.
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Subendocardial hemorrhagic necrosis in an important cause of death following cardiopulmonary bypass. The transmural distribution of flow across the left ventricle (LV), septum (SP), and right ventricle (RV) is a complex interaction of vascular resistance and myocardial compressive resistance. We studied the change in transmural blood flow in LV, SP, and RV, and left ventricular volume, following administration of cardiotonic and vasoactive drugs in the fibrillating heart. The drugs studied included calcium with and without ATP-induced vasodilation, isoproterenol, epinephrine, angiotensin, and ouabain. Calcium produced underperfusion of LV subendocardium with or without previous ATP vasodilation. Isoproterenol also caused underperfusion of LV subendocardium. Both calcium and isoproterenol decreased ventricular volume. Angiotensin increased resistance in the subepicardium and increased flow in the subendocardium, with no change in ventricular volume. Epinephrine and ouabain caused no consistent changes in transmural flow. The decreased ventricular volume produced by calcium and isoproterenol restricts flow in the subendocardium because of increased compressive resistance. Increased subendocardial flow with angiotensin indicates that subepicardial vasodilation in the fibrillating heart causes epicardial "steal," which contributes to subendocardial ischemia.
| 45,821
|
Histochemical and biophysical study of cuticle sclerotization in Pycnoscelus surinamensis L. (Blattaria).
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The problem of melaninogenesis and quinone tanning of the cuticle was examined by histochemical and biophysical methods (electroparamagnetic resonance: EPR) on normal subjects of Pycnoscelus surinamensis and on subjects with abnormal cuticular colour. The cuticle of abnormal subjects showed a lower content of polyphenolic substances and a greater positivity for the indole group. This suggests that in these insects tanning products can be synthetized differently and not derived from tyrosine but from tryptophan as postulated by Pryor (1955). Furthermore, a higher number of unsaturated aminic groups is found in abnormal subjects. Granules present only in the cytoplasm of the epidermal cells of the abnormal newly moulted subjects may indicate that the polyphenolic compound of tanning, secreted in an inactive form as 4-0, beta-glucoside, is not freed from the beta-glucosidase and remains as such in the cytoplasm.
| 45,833
|
Evaluation of cardiovascular and pulmonary changes during meperidine-diazepam anesthesia.
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Studies were conducted in 189 oral surgery out-patients to evaluate the combination of meperidine hydrochloride and diazepam for anesthesia and to determine its effect on the cardiovascular and pulmonary systems. Results showed that neither ventricular cardiac arrhythmias nor clinically significant respiratory depression occurred in the sedated patients; meperidine-diazepam proved to be satisfactory for oral surgical procedures.
| 45,841
|
Normal and altered phenotypic expression of immunoglobulin genes.
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Genetically controlled intraspecific differences between immunoglobulins (allotypes) provide valuable markers for the study of the quantitative expression of allelic and nonallelic alternative forms of immunoglobulins (Igs) during the normal development of rabbits. Heterozygous rabbits are mosaics of cells expressing different Ig-genes since fully differentiated productive cells generally secrete only one of alternative forms of Ig. The proportions of cells that differentiate to produce allelic forms of immunoglobulins during normal development depend on the particular heterozygous genotype. The normal proportions of some markers can be drastically altered if the differentiation of lymphoid cells in the young rabbit occurs in the milieu of antibody specific for one form (allotype suppression). An initiating step in the establishment of persistent allotype suppression is probably the interaction of antiallotype antibody with allotype-bearing receptors on lymphoid cell surfaces, but the mechanism for the maintenance of a state of chronic suppression may well be more complex. Allotype suppression can be viewed as one example of numerous immunological phenomena that reflect specific and finely tuned regulatory mechanisms governing the differentiation and clonal expansion of lymphoid cells destined to secrete immunoglobulins.
| 45,857
|
Benzopyranopyridine derivatives. 1. Aminoalkyl derivatives of the azaxanthenes as bronchodilating agents.
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The preparation of the four isomeric azaxanthones 3 and a number of their aromatic ring substituted derivatives is described. These ketones were converted into the title compounds which were examined for their biological properties. The most interesting compound in this series, the 1-methyl-4-piperidylidene derivative of 1-azaxanthene, shows the profile of an orally effective potent bronchodilating agent as well as a moderate antihistamine. Biological properties of this compound were compared to a number of antihistamines as well as known bronchodilating agents. Structure-activity relationships are also discussed.
| 45,881
|
Human sleep and EEG through a cycle of methadone dependence.
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The effects of oral methadone on EEG and sleep were studied in 6 male postaddicts. Continuous nocturnal measurement of EEG, EMG and EOG was used to define sleep patterns. Period analysis and power spectral analysis were performed on each 8 min sample of daytime (eyes closed) EEG. Both sleep and EEG were studied during a predrug control period, during the methadone induction phase (45-60 mg/day), stabilization phase (100 mg/day), and then 6; 10, 13, 18 and 22 weeks after withdrawal. One subject did not complete the last two withdrawal sessions. While on methadone, subjects reported that they slept more and also showed an increase in slow wave activity and a decrease in fast wave activity of their EEG during this time. Nocturnal sleep was not markedly altered during the chronic administration of methadone. Subjects reported an increase in dreaming soon after withdrawal, and then 3-5 weeks of nocturnal isnomnia. At the 6th week after withdrawal, slow wave activity in the daytime EEG was decreased, fast wave activity was increased, and mean EEG frequency was increased. REM sleep and delta sleep were increased during withdrawal. These data provide further evidence that chronic administration of narcotic analgesics may induce persistent functional changes in the central nervous system.
| 45,902
|
[An electrophysiological study of direct occipito-frontal connections in centrum semi-ovale of Papio papio].
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1. Evoked responses to single visual stimuli (VEP) and driving by intermittent light stimulation (ILS) were recorded with macroelectrodes from the central white matter (centrum semiovale) of 12 Papio papio baboons. 2. Two types of VEP were identified: VEPs with constant morphology, localized in the long associative bundles connecting the occipital, temporal and frontal lobes; VEPs with variable morphology and without any preferential localization; these probably originate from other types of fibres also belonging to the centrum semi-ovale. 3. Concerning the long associative bundles which have been individualized, they might be the equivalent of the occipito-frontal and the superior and inferior longitudinal bundles well known in man. The fusion frequency observed in these bundles during ILS increases from the frontal to the occipital lobe, because of their involvement (particularly in the parieto-temporal region) with other fibres of the centrum semi-ovale also likely to be driven by ILS. The existence of driving by ILS in these bundles demonstrates an activation of the frontal lobe by visual impulses.
| 45,946
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Selective averaging of the intracerebral click evoked responses in man: an improved method of measuring latencies and amplitudes.
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Individual click evoked responses recorded in the right and left frontal lobe in man have been correlated with different templates, that is, particular wave shapes of evoked responses, and from the maxima of the cross correlation functions individual estimates were obtained of amplitude and latency. Averages were then made of evoked responses having particular amplitude and/or latency values. Using such selected trials for averaging, better results were obtained and artificial amplitude damping avoided. It was found for example that the component N90 varied in latency between 75 and 100 msec and was linked with the behaviour of the contralateral recorded potential amplitude of P150. Furthermore it was found that the biphasic potential N230 P430 was very unstable in latency and the amplitude of the averaged potential using all trials was about 30% too small.
| 45,950
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Bacterial colonisation of jejunal mucosa in acute tropical sprue.
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Fifteen of sixteen Caucasians with acute tropical sprue were founc to have numerous aerobic bacteria closely associated with the mucosal layer of the proximal jejunum. Four species of Enterobacteria were grown in eleven patients, and concentrations were higher in the mucosal patients than in the jejunal fluid. Only one of eight control cases with similar tropical exposure but without mucosal morphological abnormalities had any similar bacteria in the mucosal biopsy. In no case were Bacteroides isolated. Since clinical and biochemical improvement only occurred on treatment with tetracycline when enterobacteria were eliminated from the mucosa, it is suggested that these organisms may be responsible for persisting jejunal abnormalities in tropical sprue.
| 46,020
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The small-intestinal mucosa in cow's milk allergy.
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Two infants investigated for allergy to cow's milk proteins exhibited a local reaginic reaction in the small intestine after ingesting cow's milk, as shown by increased mucosal IgE plasma-cells and degranulation of mast cells. IgM plasma-cells and the staining of connective tissue and basement membranes with antisera to IgG and C3 complement were also increased, indicating several simultaneous immune reactions in the intestinal mucosa. These findings may provide a sound basis for diagnosis of such an allergy and for the treatment of similar patients with disodium cromoglycate.
| 46,052
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Mucosal histochemistry in secretory otitis.
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Mucosal biopsies were taken from 20 ears with secretory otitis media (glue ear) and histochemical stainings were made for comparison with data obtained from biochemical analysis of the fluids. Acid phosphatase, lactate dehydrogenase (LD), and malate dehydrogenase (MD), the activity of which in the ear fluids was 20 to 30 times higher than in serum, were found to appear as strong precipitates in the middle ear epithelium, particularly in the top layer. Alkaline phosphatase activity was only exceptionally seen in the epithelium but appeared in the capillaries and histiocytes. Nonspecific esterase appeared irregularly in the epithelium and regularly in histiocytes. The latter two had lower activities in ear fluids than in serum. Epithelial secretory cells and subepithelial glands and cysts showed strong alcian blue (AB)-positive staining. Positive material appeared also in the cytoplasm of the epithelial cells and in the intercellular substance. Distinct PAS-positive staining appeared in the columnar epithelium and particularly in the free mucus on top of the epithelium but was less promounced in the glandular structures and absent from the cysts.
| 46,141
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Biological importance of retrograde axonal transport of nerve growth factor in adrenergic neurons.
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Previous studies have shown that nerve growth factor (NGF) produces a selective induction of tyrosine hydroxylase (TH) in peripheral adrenergic neurons and that NGF is transported retrogradely with a high selectivity from the adrenergic nerve terminals to the perikaryon. In order to investigate the biological importance of retrograde NGF transport, the following experiments have been performed; (a) effect of NGF on TH activity in superior cervical ganglia (SCG) after unilateral injection into the anterior eye chamber and the submaxillary gland; and (b) effect of systemic injection of NGF on TH activity in SCG after blockage of retrograde axonal transport by axotomy. After unilateral injection of NGF into the anterior eye chamber and submaxillary gland of both 8-10-day-old rats and adult mice, the increase in TH activity in the SCG was considerably larger on the injected than on the non-injected side although the adrenergic neurons supplying the two organs do not account for more than 25% of the total number of adrenergic neurons in the SCG. A direct diffusion mechanism could be excluded by the fact that unilateral local injection of [125 I] produced no significant side difference in the accumulation of radioactivity in the SCG 2 after injection whereas after 14 h there was a several-fold difference between the injected and non-injected side. Moreover, the nodose ganglia which are located very close to the SCG exhibited no statistically significant difference in the accumulation of radioactivity at any time. Forty-eight hours after subcutaneous injections of 10 mg/kg of NGF the increase in TH activity of the SCG amounted to 154% on the intact side and to 92% on the axotomized side. However, these experiments do not permit decisions about the extent the axotomy, as such, impaired the response to NGF. It is concluded that the biological effect of NGF results to a considerable extent, from the moiety which reaches the cell body by retrograde transport from the nerve terminals.
| 46,156
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Concealed extrasystolic ventricular bigeminy with interpolation.
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The first reported case of concealed extrasystolic ventricular bigeminy with interpolation is described. This arrhythmia is characterized by the presence of both interpolated ventricular extrasystolic beats and a presumed persistent and continuous bigeminal ectopic rhythm with exit block. The distributional pattern of sinus conducted beats in the present case conforms to a formula defining this unusual disorder of rhythm, while the appearance of manifest ectopic beats follows the rule of bigeminy.
| 46,194
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Purification, characterization and radioimmunoassay of thyrocalcitonin from rat thyroid glands.
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A highly purified preparation of rat thyrocalcitonin (TCT) has been obtained from lyophilized thyroid glands by gel chromatography following acid-acetone extraction. Biological activity of Sephadex G-50 eluates appeared in two peaks. The TCT in the major peak was concentrated, and applied to a Bio-Gel P-6 column, and a major protein peak was eluted which coincided with TCT activity. Potency, estimated by bioassay in rats, increase approximately 3500-fold from 0.075 MRC U/mg lyophilized glands to 250-400 MRC U/mg in the final product. The overall yield of TCT activity was about 36%. The purified product was characterized by chemical procedures and evaluated for its antigenic properties and use for radioimmunoassay. The purified rat TCT was used both labeled with 125I and as unlabeled standard. The following results were obtained: 1) Guinea pig antisera to either human or rat TCT were capable of binding 125I-rat TCT or 125I-human TCT; 2) Using either 125I-human or 125I-rat TCT and antisera to either TCT, pg amounts of rat and human TCT reacted in the assay while ng to mug amounts of salmon calcitonin or porcine TCT failed to react; 3) Using 125I-rat TCT and antisera to human or rat TCT, synthetic C-terminal (10-32 or 22-32) fragments of human TCT reacted well, while N-terminal (1-18) or desamide (1-32) derivatives reacted poorly or not at all; 4) Rat TCT was easily detected in normal thyroid venous plasma (5-10 ng/ml) and thyroid gland extracts (similar to 1 mug/gland) but not in peripheral blood; 5) Bioassay and radioimmunoassay of rat thyroid extracts (N equals 18) showed good agreement (r equals 0.86, p less than 0.001). The results support the idea that rat TCT is closely related to human TCT, indicate that major antigenic determinants reside in the C-terminal portion of the molecule, and show that antisera to either human or rat TCT can be used to measure rat TCT.
| 46,198
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Transposition with ventricular septal defect and pulmonary stenosis: the Rastelli operation.
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A total of 52 Rastelli operations have been performed at the Mayo Clinic for transposition of the great arteries with ventricular septal defect and pulmonary stenosis. Of the 43 patients over four years of age, two died (5%). A much higher mortality among younger children, in our earlier experience, led to a policy of early palliation, if required, by a Blalock-Taussig shunt, with later correction. The technique which evolved is described. The results of the operation thus far suggest that its success is comparable to that for the repair of the tetralogy.
| 46,225
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Energy coupling in the uptake of hexose phosphates by Escherichia coli.
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Several methods were used to study the source of energy in the uptake of hexose phosphates by Escherichia coli K12. The uptake was sensitive to inhibition by agents that affect electron transport, such as lack of oxygen, cyanide, and heptylhydroxyquinoline-N-oxide, and by agents that affect ATP utilization, such as dicyclohexylcarbodiimide and arsenate. It was also sensitive to uncouplers in the presence of absence of oxygen. The strain of E. coli used extruded protons during respiration. Uncer anaerobic conditions, the uptake of approximately 1 eg to H+ per glucose 6-phosphate. These observations are consistent with a chemiosmotic mechanism of genergized glucose 6-phosphate uptake. The rate of glucose 6-phosphate uptake was maximal in KC1, but was also stimulated by MgC12 or CaC12. Inhibition by A217, a nigericin-like antibiotic, was prevented by K+ whereas valinomycin and gramicidin inhibited in the presence or absence of K+.
| 46,228
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IgA and IgA diphtheria antitoxin responses from human tonsil lymphocytes.
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Human tonsil lymphocytes were stimulated with diphtheria toxoid and then cultured in a Marbrook culture system so that antibodies could be measured in the culture supernatant. Specific antibodies were measured with excess radiolabeled antigen and antisera specific for each immunoglobulin class. Good IgG and IgA diphtheria antitoxin responses have been obtained and responding culture supernatants were shown to neutralize toxin. The relationship between antitoxin response in vitro and immunization of donors with toxoid was investigated. It was found that at least two immunizations after the age of 6 months were necessary to prime the tonsils for an in vitro antibody response. The IgG and IgA in culture supernatants were demonstrated by immunodiffusion and were measured by radioimmunoassay. By sucrose density gradient ultracentrifugation, it was shown that 40% of the IgA produced in the cultures was greater than 7S. Evidence was obtained that neither the IgA nor the specific IgA antitoxin bears secretory piece. It appears that human lymphocytes from tonsils produce polymer IgA in vitro without secretory piece.
| 46,260
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Complement-mediated release of histamine from human leukocytes.
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Activation of either the alternative or classical pathway of complement generated a factor which induced release of histamine from both non-allergic and allergic human basophils. This factor probably is derived from the complement system since 1) its formation was associated with loss of C3 activity in human serum, 2) chemotactic factor, probably also a complement product, was generated simultaneously, 3) heat inactivation blocked its formation, 4) anti-C3 and anti-C5 blocked formation of the factor, and finally 5) anti-C5 inhibited the activity of the factor once it had been formed. It appears that both complement-mediated and allergen-mediated release of histamine from basophils are secretory, non-cytolytic pathways since both were maximal at 37 degrees C, required the presence of divalent cations, and were inhibited by theophylline. One consistent difference between these two mechanisms was noted: complement-initiated release of histamine occurred more quickly.
| 46,261
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Antigenic characterization of type C RNA virus isolates of gibbon apes.
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Type C RNA viruses initially isolated from a lymphosarcoma of a gibbon ape and from a fibrosarcoma of a woolly monkey are very closely related immunologically. However, recent studies have shown that these viruses are distinguishable in a radioimmunoassay for the 12,000-molecular-weight polypeptide (p12) of the woolly monkey virus. In the present report, an immunoassay has been developed for the p12 polypeptide of the gibbon ape type C virus. This assay is shown to further distinguish the woolly monkey and gibbon ape viruses. In type-specific assays for the p12 polypeptides of these viruses, two new type C viruses isolated from gibbons in a second colony, characterized by high incidence of hemopoietic neoplasia, are immunologically distinguishable from the original gibbon ape virus. The p12 type-specific immunoassays described in the present report may be of importance in studying the natural history of these viruses and their relationship to tumors of primates.
| 46,280
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RNA-dependent DNA polymerase activity of RNA tumor viruses. V. Rous sarcoma virus single-stranded RNA-DNA covalent hybrids in infected chicken embryo fibroblast cells.
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RNA-DNA covalent hybrids containing viral RNA have been isolated from nuclear fractions of Rous sarcoma virus-infected chicken embryo fibroblast cells shortly after virus infection. The formation of covalent hybrid structures depends upon a functional reverse transcriptase in vivo, since its appearance in cells is temperature dependent when infected with Rous sarcoma virus mutant LA335, which contains a temperature-sensitive reverse transcriptase.
| 46,286
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George Washington University technique for surgical correction of post-prostatectomy incontinence.
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We have described a procedure with long-term followup and modification for the correction of post-prostatectomy incontinence. The procedure involves the combined principle of rigidly placed support under the urethra to which is attached an inflatable, adjustable pillow, allowing for fine control of the urethral resistance. Of the 22 patients treated 16 are completely dry, 4 have occasional dampness and 2 are failures. More significant is the fact that since the silicone gel pillow has been enclosed in the marlex strap we have had 6 successes., 1 partial successs and no failures. The complication rate is almost non-existent. No infections were encountered and no prostheses were removed for other than reoperation. We believe that the combination of bony fixation plus the adjustable pillow gives the best control of the troublsome problem of post-prostatectomy incontinence.
| 46,289
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Incidence and nature of cytoplasmic hepatitis B antigen in hepatocytes.
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Hepatitis B antigen (HB Ag) in the hepatocytic cytoplasm is detected by immunofluorescence after reaction with fluoresceinated antiserum to HB Ag or by electron microscopy as numerous 20- to 30-nm. tubular and circular structures in dilated cisternae of excess endoplasmic reticulum. On light microscopy, these hepatocytes can be recognized because their cytoplasm has a ground-glass appearance and stains with Gomori's aldehyde fuchsin. Aldehyde fuchsin-positive ground-glass hepatocytes were detected in all 14 asymptomatic carriers of HB Ag and in 16 of 60 HB Ag-seropositive patients with chronic hepatitis, but not in HB Ag-seropositive acute viral hepatitis or in various other HB Ag-seronegative liver diseases. These cells are helpful in identifying on light microscopy HB Ag carriers and a portion of patients with HB Ag-positive chronic hepatitis. Nuclear HB Ag did not stain with aldehyde fuchsin. Nucleic acids were not detected in the ground-glass cytoplasm by special stains at the light or electron microscopic level. We suggest that the tubular and circular structures in the hepatocytic cytoplasm are coat material of the hepatitis B virus or virally coded host cell reaction product rather than the complete hepatitis B virus.
| 46,330
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Current status of the surgical treatment of truncus arteriosus.
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Persistent truncus asteriosus is now correctable surgically in patients with favorable anatomy. Given pulmonary arteries of reasonable size arising from any source, successful correction is possible so long as irreversible pulmonary vascular disease has not occurred. Although the majority of children with this defect demonstrate increased pulmonary blood flow, systemic-pulmonary artery shunts can be used. Also, banding of the pulmonary artery, followed subsequently by successful total correction, has been described. Recent reports of a few successful total corrections in infancy, performed with the aid of deep hypothermia and circulatory arrest, may modify the current approach. Although the majority of the reported corrections have involved aortic homograft reconstruction of the pulmonary artery, we strongly favor a synthetic prosthesis containing a heterograft valve. Based upon our clinical experience and this review of the literature, a suggested management protocol is presented.
| 46,332
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The essential role of glucagon in the pathogenesis of diabetes mellitus.
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The following evidence suggests that diabetes mellitus may not be the simple consequence of relative or absolute insulin deficiency by itself, but may require the presence of glucagon: (1) relative or absolute hyperglucogonaemia has been identified in every form of endogenous hyperglycaemia, including total pancreatectomy in dogs; (2) insulin lack in the absence of glucagon does not cause endogenous hyperglycaemia, but when endogenous or exogenous glucagon is present, it quickly appears, irrespective of insulin levels at the time. These facts are compatible with a bihormonal-abnormality hypothesis, which holds that the major consequence of absolute or relative insulin lack is glucose underutilisation and that absolute or relative glucagon excess is the principal factor in the over-production of glucose in diabetes.
| 46,337
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Plasma-high-density-lipoprotein concentration and development of ischaemic heart-disease.
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The body cholesterol pool increases with decreasing plasma-high-density-lipoprotein (H.D.L.) but is unrelated to the plasma concentrations of total cholesterol and other lipoproteins. This finding supports existing evidence that H.D.L. facilitates the uptake of cholesterol from peripheral tissues and its transport to the liver for catabolism and excretion. Plasma-H.D.L., is reduced in several conditions associated with an increased risk of future ischaemic heart-disease (I.H.D.), namely hypercholesterolaemia, hypertriglyceridaimia, male sex, obesity, and diabetes mellitus, while subjects with existing clinical I.H.D. have lower levels of H.D.L. than healthy subjects within the same community. It is proposed that a reduction of plasma-H.D.L. concentration may accelerate the development of atherosclerosis, and hence I.H.D., by impairing the clearance of cholesterol from the arterial wall.
| 46,338
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Mechanical deficiencies in scintillation counters, scanners, and gamma cameras.
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After an accident involving a scintillation counter, the machanical integrity of scintillation counters and their stands, rectilinear scanners, and gamma cameras was examined. An alarming proportion of these divices were found to be poorly designed with consequent danger to patients and staff. This class of equipment should be covered by standards incorporated in a comprehensive hospital technical memorandum.
| 46,346
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New approach to management of intracranial aneurysms.
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In six cases an attempt was made to relieve the tension on intracranial aneurysms by temporarily clamping the internal carotid artery in the neck, so as to increase the expansibility of the artery. This approach was based on the concept (or "A principle") that haemorrhage is caused by the aneurysm having to bear the full force of systolic pulse pressure when atherosclerosis prevents this pressure being taken up by the normally expansile arterial wall. Follow-up has been fairly short, but the preliminary findings in four of the six patients are encouraging. More attention must be paid in the future to the significance of atherosclerosis in the onset of bleeding from intracranial aneurysms and the incidence of postoperative problems. The argument that atherosclerosis permits the transmission of the systolic pulse directly to the aneurysm wall requires further investigation. The earlier pathological signs of atherosclerosis must receive greater attention, and post-mortem study of the walls of arteries in immediate juxtaposition to aneurysms with high-powered magnification is required.
| 46,379
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Insulin responses to oral carbohydrate in true prediabetics and matched controls.
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The definition of prediabetes by genetic criteria alone has limitations since not all such subjects progress to overt diabetes. Sequential oral glucose tolerance testing in a population has enabled the identification of 14 "true prediabetic" subjects with baseline two-hour plasma glucose levels smaller than 160 mg. per 100 ml. who subsequently developed unequivocal diabetes (two-hour plasma glucose level larger than 275 mg. per 100 ml.). All but one were matched for baseline two-hour plasma glucose and relative weight with a subject whose glucose tolerance remained unchanged during a mean follow-up period of 4 years. Fasting insulin levels and responses at 1/2, 1, and 2 hour sampling times were similar in both group and matched pair analysis at baseline. No evidence was found that subjects destined to develop diabetes have either excessive or diminished insulin secretion.
| 46,445
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Person-to-person spread of Salmonella typhimurium after a hospital common-source outbreak.
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In September, 1973, diarrhoea caused by Salmonella typhimurium developed in 32 people in a Maine hospital. Both epidemiological and microbiological evidence indicated that raw egg beaten in milk ("egg-nog") was responsible for the infection. However, 6 patients and 8 employees had not had egg-nog, and their illness developed after the source of infection had been recognised and removed. Most of these people had had direct contact with an infected patient, and presumably acquired the infection by person-to-person spread. It is concluded that person-to-person spread of S. typhimurium can occur in hospitals and can be a hazard to patients and staff.
| 46,457
|
Alveolar rhabdomyosarcoma of the ethmoid sinus.
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A case of the alveolar rhabdomyosarcoma originating in the left ethmoid sinus was reported. Despite treatment by radical excision of the tumor, irradiation and chemotherapy, the patient died of generalized metastases of the tumor six months after surgery; however, no local recurrence of the tumor was found at an autopsy. The tumor was further studied by light and electron microscopic procedures.
| 46,581
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Chemotherapeutic drugs increase killing of tumor cells by antibody and complement.
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When the ascitic forms of two antigenically distinct guinea pig hepatomas induced by diethylnitrosamine are treated in vitro with chemotherapeutic drugs, their sensitivity to killing by xenogeneic antibody plus guinea pig complement increases. The effect is dependent on drug dose, is reversible, and does not appear to be due to increased antigen expression or fixation of the early acting components of guinea pig complement.
| 46,622
|
Use of peroxidatic-enzyme staining to enhance resolution of cultured mammalian cells under phase microscopy.
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Staining of glutaraldehyde-fixed mammalian cells with peroxidatic enzymes (horseradish peroxidase or horse heart cytochrome c) greatly enhances resolution of their structure under phase microscopy. The topography of cell processes and regions of intercellular contact and overlapping is resolved precisely, even in dense cultures mounted in media which ordinarily do not permit clear demonstration of these areas. The technique is therefore a useful aid to the study of cultured cells with phase optics. Labeling depends on introducing free aldehydes into cells through the use of bifunctional fixatives such as glutaraldehyde. Acetone or formaldehyde fixation prevents staining, and labeling intensity is greatly diminished by pretreatment with spermine, a polyamine that reacts with glutaraldehyde. Electron microscopy reveals that peroxidase tags membranes preferentially; some areas are labeled smoothly, others in a punctate manner. Ribosomes are sharply contrasted, but nuclei remain unstained. Cytochrome c labels condensed nuclear chromatin intensely, and also stains ribosomes and portions of the cytoplasmic ground substance; membranes are mostly unmarked.
| 46,631
|
Cytological differentiation of asymptomatic pancreatic islet cell tumours in autopsy material.
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In eleven cases thirteen pancreatic islet cell adenomas were found in autopsy material from 1366 adult cases. Ten of the adenomas were solitary, while 3 small adenomas were observed in a single case. Another four possible solitary adenomas were observed, but their identity was uncertain owing to marked fibrosis. All the adenomas contained A-2 (A)-1 cells but no B (B)-1 cells. Nine of them also contained A-1 (D)-1 cells. The majority of cells in the adenomas were A-2 cells or cells which did not stain with any of the techniques used. The 4 possible adenomas contained islet cells (A-1, A-2, B) in different proportions. With one exception the patients with adenomas and possible adenomas were 65 years of age or older, and in some of these cases adenomas or hyperplasias were also found in other endocrine organs. The frequency of gastroduodenal ulcers or scars in the cases with adenoma or possible adenoma did not differ notably from that found in the cases without pancreatic adenomas. Among the cases with pancreatic adenoma and possible adenoma there were 3 patients with maturity onset diabetes mellitus, but otherwise no clinical symptoms of endocrine disturbances were noted.
| 46,649
|
Limitations of the usefulness of the d-xylose absorption test.
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The results of the conventional 5-hour d-xylose absorption test were surveyed in 38 subjects with disease of the jejunal mucosa, giardiasis or bacterial overgrowth, or no small-bowel disorder. The test was in error in 20-40% of cases, depending on the disease category, and the error for the entire group was 30%. We conclude that the test yields little guidance for diagnosis or therapy of clinical problems and is superfluous when a jejunal biopsy can be obtained.
| 46,695
|
Changes in the ratio between serum and "specific" levels of human chorionic gonadotropin in different trimesters of pregnancy.
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Sixty-one sera from different trimesters of pregnancy were analyzed by two 125-I-NIH-HCG assay systems, employing anti-intact HCG serum and anti theta-HCG serum, respectively. The ratios of the levels measured in the two assay systems changed with the duration of pregnancy. The ratios during trimesters 1,2, and 3 were 2.94, 1.99, and 2.37, respectively. The cross-reactivity of proteohormones other than HCG was tested in both the assay systems. The two assay systems could be comparable in their high degree of specificity. However, the relative affinities of intact HCG and theta-HCG in the two assay systems were observed to be different. It was suggested that the significant differences in the ratios of the levels measured by the tow assay systems might have been infulenced by the occurrence of theta-HCG in serum and that the levels of the subunit must have changed at different stages of pregnancy.
| 46,715
|
Monitor of chemotherapy in gestational trophoblastic neoplasm by radioimmunoassay of the beta-subunit of human chorionic gonadotropin.
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Radioimmunoassays and bioassays based on the reactions of the native molecule of human chorionic gonadotropin (HCG) fail to differentiate HCG from pituitary luteinizing hormone (LH). An assay based on the beta-subunit of HCG which detects HCG exclusively has been used in our laboratory to monitor patients undergoing chemotherapy for gestational trophoblastic disease (GTD). We have been able to differentiate minimal, persisting tumor activity from normal levels of pituitary gonadotropins and have based therapy on these findings. Alternatively, treatment has been terminated when HCG is no longer detectable in the serum. Tumor activity has been detected in the beta-subunit assay at a time when biologic activity in the urine indicated remission.
| 46,716
|
Genetic studies in the Markham Valley, northeastern Papua New Guinea: gamma globulin (Gm and Inv), group specific component (Gc) and ceruloplasmin (Cp) typing.
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Genetic studies in the Markham Valley, northeastern Papua New Guinea; Gamma globulin (Gm and Inv), group specific component (Gc) and ceruloplasmin (Cp) typing. M. S. Schanfield, Eugene Giles and H. Gershowitz, Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48104. Immunoglobulin allotyping was carried out on 680 serum samples from inhabitants of the Markham Valley, Papua New Guinea (seven villages speaking the same Melanesian [PAP] speaking village). Family and population data verified the presence of Gm-ag, G-ab and Gm-afb among the MN speakers and Gm-ag, Gm-axg, Gm-ab and Gm-afb among the PAP speakers. The frequency of Gm-ag was between 0.048 and 0.235, while the frequency of Gm-ab was between 0.427 and 0.627 and the frequency of Gm-afb ranged between 0.261 and 0.424 among the seven MN villages; the single PAP village had frequencies of 0.568, 0.160, 0.213 and 0.059 for Gm-ag, Gm-axg, Gm-ab and Gm-afb respectively. The frequency of Inv1 ranged between 0.034 and 0.095 in the MN villages and 0.014 in the PAP village. The rare occurrence of Gm(x) without Gm(g) was explained by the presence of a Gm-axfb haplotype, while in two PAP families the presence of Gm(x) without Gm(g) was explained by the abnormally weak expression of Gm(g) in a Gm-axg haplotype. A total of 654 sera were typed for Gc, with the seven MN villages ranging between 0.350 and 0.650 for Gc-1, 0.312 and 0.575 for Gc-2 and between 0.017 and 0.112 for Gc-Ab; the single PAP village had a value of 0.627 for Gc-1, 0.165 for Gc-2 and 0.208 for Gc-Ab. A total of 693 sera were tested for ceruloplasmin type. All showed the common Cp(b) phenotype.
| 46,722
|
The roentgenographic and clinical findings in Whipple's disease. A review of 8 patients.
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Out of 8 patients with Whipple's disease, 7 had roentgenographic findings consisting of slight dilatation of the small bowel, with thickening of the mucosal folds. The eighth patient had no abnormality on roentgenographic study. This series represents the first in which the roentgenographic changes have been quantitatively assessed. Confirmation of the diagnosis by biopsy is important because antibiotic treatment results in marked improvement both clinically and roentgenographically.
| 46,724
|
Affinity of cellular constituents of two bacteria for fluorescent brighteners.
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Two fluorescent brighteners were used to stain an isolate of Bacillus cereus var. mycoides and soil pseudomonad. The stained organisms were fractionated by two procedures to determine which cellular constituents were reacting with the brighteners. Both fractionation procedures provided evidence that the brighteners were adsorbed to proteins within the cells. Microscopy examination of ghost cells of the bacillus showed that cell walls were not being stained. Spheroplasts of the bacillus and the pseudomonad were stained by the brighteners.
| 46,739
|
Cultivation of leukemic human bone marrow cells in diffusion chambers implanted into normal and irradiated mice.
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In order to elucidate the question of whether the maturation defect in vivo in acute leukemia is due to environmental or cellular factors, we have cultured human leukemic cells in a nonleukemic milieu, i.e., diffusion chambers implanted into the abdominal cavity of normal and irradiated mice. For each harvest, the cell count was measured and differential counts and the number of peroxidase-positive cells determined. The cell number decreased with time, without significant difference between culture in irradiated (500 rads) and normal mice. The blast cells succeeded only in developing distorted promyelocytes and myelocytes. There was a general pattern of increase in the number of peroxidase-positive cells. The study supports the concept that acute myeloid leukemia (AML) is a disturbance of cellular maturation due to cellular rather than environmental defects.
| 46,761
|
An adrenergic component of the nervous apparatus of the aortic reflexogenic zone.
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The structural organization of the adrenergic (sympathetic) component of the autonomic innervation of the depressor zone of the cat aortic arch was studied by luminescence microscopy of the catecholamines. A terminal adrenergic plexus, branching extensively in the connective-tissue basis of the depressor area of the aortic arch, was discovered. The participation of vessels supplying blood to the depressor area was established. Adrenergic neurons were found in the territory of the depressor zone of the aortic arch. It is postulated that the adrenergic component of the depressor zone of the aortic arch participates in the peripheral mechanism of the regulatory effects of the sympathetic nervous system on the baroreceptor apparatus.
| 46,763
|
Time course of development of supersensitivity to topical acetylcholine in partially isolated cortex.
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In alert monkeys the time course for development of supersensitivity to topical acetylcholine in partially isolated frontal cerebral cortex was determined. Thresholds for paroxysmal discharge fell progressively and markedly during 3 weeks, further in 5 and somewhat more after 6 months. ACh supersensitivity was demonstrated in chronic "isolated" occipital cortex. Epileptiform discharges were recorded selectively from chronic partially isolated frontal cortex on peripheral nerve stimulation and these spread, causing a clinical convulsive siezure when the open end of the isolation extended into the precentral gyrus. The basic mechanisms responsible for the supersensitivity are unknown but evidence presented and much in the pertinent literature is in keeping with the hypothesis that partial isolation of cortical cells, i.e., denervation, deafferentation, or disuse may be important. It is suggrested that peripheral nerve stimulation, like arousal, may cause an outflow of ACh on the normal brain surface and over the open end of a partially isolated area, which, especially, in the presence of a diminished cholinesterase activity (in partially isolated cortex), could act like topical ACh, cause a DC shift and an epileptiform discharge.
| 46,800
|
EEG correlates of visual-motor practice in man.
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Special analysis of EEG signals was performed for 15 subjects engaged in three motor tasks of differing difficulty. A measure of average weighted coherence (C) was computed between the six possible combinations of four scalp areas: Oz, C3, C4 and Fz. In all subjects, regardless of task, scalp recordings over cortical areas known to have relatively dense fiber connections had significantly greater C values. However, the effects of task difficulty and practice were superimposed upon this basic pattern. Thus, the most difficult task (pursuit-rotor tracking) resulted in the highest coherence levels, while the least difficult task (visual tracking only of the pursuit-rotor disk) resulted in the lowest coherence levels. Practice, on the other hand, was associated with a significant decrease in overall level of coherence. This decrease is consistent with an interpretation of reduced task difficulty due to visual-motor learning. The results of the present study suggest that patterns of scalp EEG coherence may reflect some aspects of the underlying pattern of anatomical pathways, as well as the more dynamic properties of task difficulty and visual--motor practice.
| 46,821
|
Use of the analytical electron microscope (AEM) in cytochemical studies of the central nervous system.
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Central nervous tissues (median eminence and arcuate nucleus) were studied by means of energy dispersive x-ray analysis using electron optical systems (analytical electron microscopy). These studies were conducted after the tissue had been treated specifically for localized biogenic amines (BA). The results indicate that not only is the BA cytochemical reaction highly specific, and that BAs can be localized intraneuronally in areas not previously identified, but also that the analytical electron microscope is a very valuable and potentially powerful tool in the studies of inclusion bodies and organelles in the central nervous system and other tissues. Thus, the nonspecific density production by osmium tetroxide can be elucidated from the specific BA reaction plus other areas of the nervous system containing density producing heavy metals, i.e., iron are readily identifiable.
| 46,860
|
Optical versus radiographic magnification for fine-detail skeletal radiography.
|
Fine-detail radiographic techniques for peripheral skeletal imaging have gained wide clinical acceptance. In this study, the imaging properties and clinical applications of the optical magnification technique, which employs fine-grain industrial film and a large focal spot, are compared quantitatively and qualitatively with those of three slow screen-film techniques, namely, contact exposure with a large focal spot, 2 times radiographic magnification with a 0.3 mm focal spot, and 4 times radiographic magnification with a 50 mu focal spot. The modulation transfer functions (MTF's) of the recording systems and focal spots are obtained and film sensitometry performed. Clinical comparisons are made for patients with metabolic, arthritic, and neoplastic skeletal disorders. The results illustrate the superiority of the optical magnification technique over contact or 2 times magnification techniques using slow screen-film systems. If a microfocus tube is used, however, direct radiographic magnification may provide images comparable in resolution, noise and contrast to those made with the optical magnification technique, and at lower radiation exposure to the patient.
| 46,857
|
Role of the eosinophil in the allergic reactions. I. EDI-an eosinophil-derived inhibitor of histamine release.
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An inhibitor of histamine release was found to be associated with the human eosinophilic leukocyte. This eosinophil-derived inhibitor (EDI) was released from eosinophil-rich fractions upon sonication or interaction with immune reactants (specific allergens or anti-IgE). EDI was found to exert its inhibitory action at the target cell level by increasing the intracellular levels of cyclic-AMP. Preliminary electron microscopic studies show the presence of IgE on the eosinophilic leukocyte and it is suggested that the allergen or anti-IgE-induced release of EDI might be due to a direct interaction of these immune reactants with the eosinophil-bound IgE antibody. The results also suggest that by virtue of liberating a histamine release inhibitor such as EDI, the eopsinophil assumes a modulating role in the allergic inflammatory reaction.
| 46,900
|
Amines, anticonvulsants, and epilepsy.
|
Concentrations of 5-hydroxyindoleacetic acid (5-H.I.A.T.) in cerebrospinal fluid (C.S.F.) were significantly raised in twenty-seven anticonvulsant-treated epileptic patients compared with fifteen untreated epileptics and twenty-two neurological controls. This rise was not seen until therapeutic blood-levels of phenobarbitone and diphenylhydantoin had been achieved, and was most striking in clinically intoxicated patients. Similar trends were seen in C.S.F. homovanillic acid (H.V.A). There was a close correlation between C.S.F. 5-H.I.A.A. and H.V.A., especially in the treated epileptics. These findings have implications for the antiepileptic and toxic effects of anticonvulsant drugs.
| 46,954
|
Assessment of outcome after severe brain damage.
|
Persisting disability after brain damage usually comprises both mental and physical handicap. The mental component is often the more important in contributing to overall social disability. Lack of an objective scale leads to vague and over-optimistic estimates of outcome, which obscure the ultimate results of early management. A five-point scale is described--death, persistent vegetative state, severe disability, moderate disability, and good recovery. Duration as well as intensity of disability should be included in an index of ill-health; this applies particularly after head injury, because many disabled survivors are young.
| 46,957
|
Costs of detecting and treating cancer of the uterine cervix in North-East Scotland in 1971.
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In 1971 the Aberdeen cytology service handled 22,291 cervical smears--threequarters from women participating in a screening programme and the rest from women with symptoms who were referred to hospital. As a result of screening, 56 preclinical cases of cancer of the cervix uteri were treated in hospital; 13 others were classified as less than preclinical. Of the gynaecological patients 20 had clinical cancer and 29 had less than preclinical lesions. From estimates of the costs of running the cytology service and of hospital inpatient costs it is possible to derive figures for detecting and treating preclinical cases and investigating and treating clinical cases. The cost to the Health Service of detecting and treating each preclinical case was slightly less (445 pounds) than that for impatient treatment of each clinical case (487 pounds). However, if mass screening were abandoned cytology would almost certainly continue for women referred to hospital with symptoms, and, if the costs of taking and examining these smears is taken into account, the cost per clinical case treated nearly doubles to 835 pounds. Had outpatient and other follow-up costs been included, the difference in service costs would be even greater. Comparison of these figures assumes the controversial point that preclinical cancer will always progress to invasive carcinoma if left untreated and takes no account of inflation and discounting.
| 47,092
|
[Experimental malakoplakia in the kidney].
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Malakoplakia in kidney of rats was caused experimentally by injection of large quantities of not purified endotoxin-antigen complex of Escherichia coli 0 75 (O. coli 127 97 CDC 0 group 75; American Type Culture Collection, Eight Edition 1968, page 24). The extract in the beginning became surrounded by leukocytes, later by macrophages. The latter then were transformed into characteristic Hansemann cells. From the 8th day on started the depletion of calcium phosphate in the cytosegresomes of macrophages, thus forming the Michaelis-Guttmann bodies, necessary for the diagnosis of malakoplakia. It is believed that complex of endoxin- and antigen of Escherichia coli may take a part - at least in certain cases - in formation of malakoplakia in human.
| 47,145
|
Induction of translocations by cyclophosphamide in different germ cell stages of male mice: cytological characterization and transmission.
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Cytological and fertility tests were performed in F1 male mice derived from different germ-cell stages of male parents treated with cyclophosphamide (350 mg/kg body weight). The objectives of the present experiment were: (I) to determine the sensitivity of the male germ-cell stages to the induction of translocations by the compound, and (2) to characterize translocation configurations in F1 and F2 males, in order to obtain information about the pattern of chromosome breakage induced and its transmission to subsequent generations. Of 508 F1 males studied, 39 were partially sterile. The group of males conceived 8-21 days after treatment contained by far the highest proportion of partially sterile animals (30%). It was also the only group in which totally sterile animals (11%) were found. Of 25 semisterile males from this group, 24 gave evidence of translocations when spermatocytes were scored at diakinesis. The translocation frequencies in F1 derived from treated spermatozoa and spermatocytes were 14 and 1%, respectively. No translocations were detected cytologically in 6 semisterile males derived from treated spermatogonial stages. These results indicate that spermatid stages are especially sensitive to the mutagenic action of cyclophosphamide. In 21 of the 31 semisterile translocation males (68%), the majority of the spermatocytes contained 18 bivalents plus a ring-of-four configuration, indicating that both breakpoints were relatively centrally located; and in several of these males, the frequency of cells with rings was close to 100%. In another 9 F1 males (29%) the predominant multivalent configuration was a chain-of-four, indicating one of the breakpoints to be relatively more terminally located; and in one male (3%), the majority of cells had two unequal bivalents, indicating both breakpoints to be fairly close to the ends of the chromosomes involved. Determination of centromere positions by the use of C-banding showed that chain-of-four configurations in any one male were predominantly of a given type..
| 47,147
|
Double-blind study of the analgesic effect of indoprofen (K 4277).
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In a double-blind study, indoprofen was superior to placebo in decreasing pain in patients with primary and metastatic cancer and with neuralgia. A single oral dose of 200 mg was more active than a 100-mg dose. The preferences of patients proved to be a more sensitive parameter in this study than scores of pain intensity, pain relief, and other related measurements (SPID, TOTPAR, and Peak PID).
| 47,280
|
Retardation of development including immunogenic expression of histocompatibility antigens in mice--by postnatal administration of antiandrogenic steroid.
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A specific antiandrogenic steroid cyproterone acetate was administered daily to mice of three different inbred strains starting from the day of birth until the age of 30 days. The total dose per mouse was 17.2 mg. This treatment resulted in developmental retardation which was manifested in a number of ways: at the age of 30 days, the weight of the body was well as spleen, testes and particularly thymus was significantly reduced; histologically, the normal proportion of the red and white pulp in the spleen was changes; spermatogenesis (but not oogenesis) was markedly retarded corresponding to the age of 12-15 days in normal males; also skin displayed a persisting immaturity as reflected by an abundance of mast cells. Minor signs of toxic changes were seen in the liver. Skin grafts from CA-pretreated donors had a subnormal immunogenicity; when transplanted across the MSA-barrier, they survived significantly longer than control grafts and about 23% took. Significantly prolonged survival was also observed with H-3 incompatible skin grafts from CA-pretreated donors, particularly from male donors. Across the barrier dicated, but did not reach a level of significance. The present study extends our previous observations concerning the androgen dependence of a normal immunogenic expression of H-antigens. The antiandrogenic effect of CA is comparable to the more complex effect of neonatal orchiectomy in terms of the subnormal immunogeneity of MSA-incompatible skin grafts from 30-day-old males which seems to be arrated at a stage typical for 1-2-day-old normal males.
| 47,300
|
Genetic control of sensitization to structurally unrelated antigens and its relationship to histocompatibility antigens in guinea-pigs.
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Five strains of guinea-pigs homozygous for GPL-A and 2/13 histocompatibility antigens were sequentially immunized with seven structurally unrelated antigens (TGAL, BPO-BGG, ASAN, BPO-PLL, phenetidine, horseradish peroxidase and DNP-dodecapeptide). Considerable differences in the immune response were observed, as measured by delayed skin reactivity and antigen-induced lymphocyte stimulation in vitro. The data presented show that when the progeny of various back-cross matings are analysed for their responder status, the responses to the antigens (TGAL, BPO-BGG, phenetidine and ASAN) are in most cases linked to the genes controlling the respective histocompatibility antigens. However, it appears that the responses to the various antigens in our system may be under polygenic control.
| 47,308
|
Release of extracellular enzymes from Bacillus amyloliquefaciens.
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Washed-cell suspensions of Bacillus amyloliquefaciens secrete significant amounts of the extracellular enzymes alpha-amylase and protease for about 15 min in the almost complete absence of protein synthesis. This apparently represents release of preformed enzyme en route to secretion. The release was independent of energy but was affected by temperature. Pulse-labeling experiments showed that newly synthesized enzyme molecules are either immediately released into the external medium or equilibrate with the preformed enzyme prior to eventual secretion. The results are compatible with a model of secretion whereby enzyme molecules emerging from the cell membrane become temporarily restricted by the cell wall so that a small pool of active enzyme accumulates in this region.
| 47,325
|
Orcein staining of hepatitis B antigen in paraffin sections of liver biopsies.
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Liver biopsies from 97 hepatitis B antigen (HBsAG)-positive patients were stained by a modified orcein method described by Shikata et al (1974) in order to detect the antigen in liver tissue. The results were consitently negative in acute hepatitis, but positive in nearly two-thirds of biopsies from 53 patients with chronic liver disease. The distribution of positive staining was frequently irregular so that there is a problem of sampling error in needle biopsies. The deposits were seen in the cytoplasm of liver cells and occasionally in Kupffer cells, but never in nuclei. There was an inverse relationship between staining and parenchymal necrosis. Biopsies from asymptomatic HB(s)Ag carriers were often strongly positive, as were "ground-glass" hepatocytes in carriers and patients with chronic liver disease. The mechanism of staining is unclear but may be related to the presence of disulphide bonds in (HBsAG. The technique is simple and of use both in fresh and stored material.
| 47,336
|
Competition for antigen by cell populations having receptors with the same specificity but of different idiotype.
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All normal A/J mice immunized with keyhole limpet hemocyanin-p-azophenylarsonate (KLH-Ar) produce anti-Ar antiboides, some of which share a cross-reactive idiotype. The present results indicate that the biosynthesis of antibody molecules bearing this idiotype does not occur in mice having an excess of lymphoid cells with receptors for Ar that lack the idiotype. This was shown, first, by introducing into normal, nonirradiated mice lymphoid cells from mice which had been suppressed with respect to production of the idiotype and then immunized with KLH-Ar. The recipients failed to express the idiotype upon immunization. Alternatively, cells from suppressed, mice were transferred into lethally irradiated syngeneic recipients, followed 17 days later by normal cells. All recipients expressed the idiotype upon immunization. If, however, the recipients were challenged with antigen between the two cell transfers, antibodies bearing the idiotype were not produced during subsequent immunization. Arguing against active, cell-mediated suppression was the production of the idiotype by normal cells in the presence of cells from a suppressed animal. However, the possibility of active suppression by hyperimmune suppressed cells was not ruled out. On the basis of the present data, the simplest interpretation is that cells with anti-Ar receptors from immune, suppressed animals, being present in larger numbers, compete successfully for antigen with nonimmune cells and thus prevent the expression of the idiotype. The system may provide a basis for quantitative studies of competition among cells for a limited supply of antigen, particularly if B cell populations are utilized.
| 47,356
|
In vitro response of mouse spleen cells to the solid phase immunogen DNP-O-Bio-Gel.
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The in virto immunogenicity of the solid-phase hapten, dinitrophenyl-ornithine-Bio-Gel (DNP-O-Bio-Gel), was investigated in cultures of mouse spleen cells. Appropriate combinations of cells and immobilized hapten were determined. Large numbers of direct anti-hapten plaque-forming cells (PFC) were generated when 1 times 10-7 C57BL/6 or C57BL/10 spleen cells were cultured with 4 times 10-3 DNP-O-Bio-Gel beads. Specificity studies of the responses of cultured spleen cells to DNP-O-Bio-Gel yielded the following results: soluble DNP-ornithine or DNP-bovine gamma-globulin inhibited the induction of anti-hapten PFC by DNP-O-Bio-Gel; neither dinitrophenyl-Bio-gel (DNP-Bio-gel) nor ornithine-Bio-Gel (O-Bio-Gel) induced anti-hapten responsiveness; furthermore, neither DNP-Bio-Gel nor O-Bio-Gel inhibited the induction of PFC by DNP-O-Bio-Gel. It was concluded, from the results of these specificity experiments, that a spacer, ornithine, is required for immunogenicity of immobilized DNP; and that the Bio-Gel bead, itself, acts solely as a physical carrier for the hapten.
| 47,361
|
Neglected coeliac disease.
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A review has been carried out of patients diagnosed as having coeliac disease some years previously and subsequently lost to follow-up. Most were unaware of the need for continuing treatment and had returned to a normal diet. The resulting morbidity was slight, although one patient had died of a small-bowel lymphoma. If untreated coeliac disease is indeed a pre-malignant condition, then it is suggested that there must be a large population at risk, with no motivation to return to treatment other than the risk of malignancy itself.
| 47,419
|
Needle biopsy for muscle chemistry.
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Needle biopsy can readily provide samples of human skeletal muscle for biochemical analysis. Muscle metabolites are measured by enzymic microanalytical techniques and electrolytes by neutron-activation analysis. This paper summarises the methods of analysis, gives the normal ranges for muscle contents of metabolites and electrolytes, and reviews the reported changes in a number of neuromuscular and metabolic disorders. Muscle is a fairly homogeneous tissue in health, but replacement with fat and fibrous tissue in myopathies causes error in analyses unless metabolites are referred to a reliable standard. It is recommended that needle-biopsy samples to be freeze-dried and dissected to remove connective tissue before analysis. Total creatine (phosphorylcreatine+free creatine) total adenosine+inosine nucleotides, and potassium and phosphorus separtely correlated very highly with sample dry weight after dissection, suggesting that these may be used as standards. When assessing whether a given metabolite is present in an abnormal amount, it is probaby advisable to check the content with reference to more than one standard, since one or more of these may be changed in disease.
| 47,494
|
Association of foot lesions with retinopathy in patients with newly diagnosed diabetes.
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A proportion of newly diagnosed diabetic patients have features so characteristic that they form a distinct syndrome. The patients are predominantly male and present with a foot lesion which is often long established. They are subsequently found to have diabetes mellitus and diabetic retinopathy. In addition, many of them manifest a striking indifference towards their illness. 47 such patients have been seen between the years 1960-1969 at a diabetic clinic in Birmingham which saw a total of 6451 newly diagnosed patients in the same period. 26 of the 45 patients in whom follow-up was complete have died. The present state of health of the 19 surviving patients indicated that the prognosis is poor for patients who have retinopathy and foot lesions when diabetes is diagnosed.
| 47,532
|
Physiological mechanisms for cardiac control by nutritional intake after early maternal separation in the young rat.
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Series of analytic experiments are presented that explore possible physiological mechanisms for the control of cardiac rate by nutritional intake in the pre-weanling rat. The essential properties of the nutrient and the first site of action were studied by using fluids of different pH, osmolality and chemical composition administered intravenously as well as intragastrically. Several probable effector pathways were explored: neuroendocrine (adrenal medullary and adrenocortical, thyroid), cholinergic and adrenergic. Pharmacological blocking agents, surgical removal of glands, replacement hormones and spinal cord trasaction were utilized. Afferent pathways such as vagus and splanchnic systems were approached surgically and the gastrointestinal hormones, histamine, insulin and glucagon, were studied by administration and pharmacological blockade. The evidence tended to rule out a number of possible mechanisms and pathways and to make it appear likely that nutrient acts initially at the gut wall, that the CNS then responds by increasing tone in the classical spinal cardioacceleratory pathways to the beta-adrenergic synapses of myocardium.
| 47,639
|
[Orthorhythmic pacemaker and salvo-like cardiac stimulation. New procedure aiming at the suppression and prophylaxis of cardiac arrhythmia and the determination of electrophysiological measurement magnitudes in vivo].
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The orthorhythmic pacemaker (ORPM) represents a new apprach in cardiac stimulation. The use of conventional demand pacemakers is essentially limited to the treatment of bradycardic arrhythmias. The principle of the ORPM consists in early stimulation after premature beats, taking into account the R-R interval of the preceding spontaneous beat. In this "extrasystolic pacing" the escape interval is not fixed; rather, the premature electric stimulus will be fired after an interval, the duration of which can be selected as a fraction of the preceding cycle length. The ORPM enhances the possibilities for treatment of atrial and ventricular tachycardias due to re-entry. The idea of "bursts" of stimulation e.g. the firing of up to ten impulses within a short time, is put into practice in the actual latest ORPM model. It widens the application of the ORPM principle and allows simplified measurement of the refractory period.
| 47,644
|
Recent results in the surgical treatment of Fallot's tetralogy.
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Tetralogy of Fallot consists essentially of two abnormalities: a large, unrestrictive ventricular septal defect and severe obstruction to the outflow of the right ventricle. A clear understanding of the principles described in this article should result in a mortality of under 5% after complete correction of tetralogy of Fallot.
| 47,651
|
Soluble proteins of bronchopulmonary secretions from patients with cystic fibrosis, asthma, and bronchitis.
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The concentrations of nine plasma proteins were determined by quantitative immunoelectrophoresis in sputum specimens from 29 patients with cystic fibrosis (CF) and from 24 patients with severe asthma and chronic bronchitis. The results suggested that the population of CF patients could be divided into two groups in spite of an absence of difference in clinical status between the groups. Average concentrations of seven plasma proteins in sputum of group I CF patients were identical with those in sputum of patients with bronchitis, but the average concentrations of six of these proteins in sputum from group II CF patients were higher than those in specimens from the bronchitic patients and were similar to corresponding concentrations in sputum from patients with asthma, all of whom were examined while in status asthmaticus. The average concentrations of 14 secretory proteins were the same in all sputum specimens whether or not they were produced by patients with cystic fibrosis, asthma or bronchitis. It was concluded that the concentrations in the bronchopulmonary secretions of proteins associated with host defence were not diminished in patients with cystic fibrosis, and failure to produce adequate concentrations of proteins with antimicrobial activity was unlikely to be responsible for the above average susceptibility to chest infection in cystic fibrosis. It is suggested that there exists a group of CF patients in whom a pulmonary allergic reaction generates an inflammatory response as severe as that characterizing status asthmaticus and that this response could be detrimental.
| 47,656
|
[Reproduction of leukovirus RD-114 in diploid and heteroploid human cells].
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The capacity of leukovirus RD-114 to replicate in human embryo lung diploid cell cultures and continuous human angiosarcoma cell cultures (AS and 709 lines). Differences in the capacity to support the virus reproduction were observed in the two strains of human embryo lung cells (HEL-1 and HEL-3) and the two continuous angiosarcoma cell lines. No virus reporduction was observed in mouse and rat cell cultures. No cytopathic or transformation changes were caused by the virus in any of the systems examined.
| 47,667
|
Characterization of spermatozoal auto-, iso- and allo-antigens.
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Three approaches are utilized to study and characterize spermatozoal antigens. An immunological approach has demonstrated the presence of spermatozoal auto-, iso- and allo-antigens. Spermatozoal auto-antigens studies by several authors are able to induce the whole spectrum of immune reactions (delayed hypersensitivity, complement-fixing antibodies and anaphylactic antibodies0 as well as of autoimmune aspermatogenic orchiepididymitis (AIAO). Different extraction procedures result in various preparations and even in different independent autoantigens (at least four), one protein, one membrane-linked antigen and at least two glyco-proteins. Spermatozoal iso-antigens stricto sensu are determined by the Y chromosome and present on at least 50% of the spermatozoa. Spermatozoal allo-antigens are also present at the surface of spermatozoa, especially blood group antigens (ABO and MNS systems), transplantation antigens (HL-A, H-2) and also some other unidentified ones. A biochemical approach has mainly been directed towards spermatozoal enzymes that have been directed towards spermatozoal enzymes that have been shown to be antigenic even in the species of origin. This is the case for lactic dehydrogenase LDH-X (a mid-piece enzyme) and for acrosomal enzymes, e.g., hyaluronidase, possibly sorbitol dehydrogenase and trypsin-like acrosomal proteinase (the auto- and allo-antigenicity of the latter having not been established). At least three of these enzymes are known or supposed to play a role in the process of fertilization. A clinical approach has described the presence of spermatozoal-coating antigen(s), such as transferrin or blood group substances from secretors obtained following the admixture of the secretions of the seminal vesicles. Indications were also obtained for the existence of antibodies directed against defined antigens. Several types of localization of antibodies on spermatozoa were described: acrosome (front part), equatorial segment, post-nuclear region, mid-piece and tail. Attempts at fractionation of human psermatozoal antigens are still at a preliminary stage. Whatever the approach, the main interest of these antigens is that they are able to induce, in the species of origin or in a related species antibodies capable of interfering with the normal process of reproduction, especially fertilization..
| 47,684
|
HL-A, fertility and natural selection.
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The antibodies occasionally produced in gravid females usually cause no adverse effects and the mother may become hyporesponsive. Exceptions may occur in some cases of abortion where frequency of antibodies appears to be unduly high. Sperm antigens in the mouse include T locus alleles as well as H-2 and H-Y. The T locus is involved in differentiation. T locus alleles are expressed on early but not late embryos. A search for similar factors in man is in progress. The antigenic differences between sperm and mother and between foetus and mother may be important in natural selection. It is possible that the union of sperm with ovum is non-random and that the ovum can select "compatible" sperm through recognition of cell surface markers present on sperm. Immunologic differences between mother and foetus may cause local "graft-versus-host" reactions in the placenta. This leads to increased placental size and may be a factor in hybrid vigour as well as a protective device.
| 47,686
|
Acute viral hepatitis: factors possibly predicting chronic liver disease.
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A number of clinical, biochemical, immunological and morphological variables were recorded at first admission of 500 consecutive patients with biopsy verified acute viral hepatitis in the period February 1969-June 1972. In February 1973, 28 of these patients had a morphologically documented chronic liver disease: 4 cirrhosis of the liver, 15 chronic aggressive hepatitis, and 9 chronic persistent hepatitis. 74 patients were followed up until morphological normalization took place. The initially recorded variables in the two groups were compared, and the following factors were significantly higher in the group with subsequent development of chronic liver disease:--frequency of drug addicts, median of the highest gammaglobulin, ANA, SMA, partial destruction of the limiting membrane, incidence of piecemeal necrosis, and pronounced plasma cell infiltration in the portal tracts. These preliminary results suggest that factors in the initial phase of acute viral hepatitis can be helpful to some extent in predicting the course and prognosis of the disease.
| 47,692
|
Nucleolar size in benign and malignant plasma cell proliferation;.
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Nucleolar and nuclear size of bone marrow plasma cells has been studied in 26 cases of myeloma, 19 of benign essential monoclonal gammapathy (BEMG) and 9 without an M-component. Bone marrow smears were Feulgen-stained to visualize nucleoli and nuclei. Nucleolar area, nuclear area and the ratio nucleolar area/nuclear area were calculated. The myeloma group differed from the other two groups in having plasma cells with larger nucleoli, larger nuclei and an increased ratio nucleolar area/nuclear area. No difference was found between the BEMG group and the cases without an M-component. In some cases--in which the absence of osteolytic lesions at X-ray examination, a low plasma cell percentage in bone marrow smears or a low M-component concentration initially made the diagnosis of myeloma uncertain--the observation of enlarged nucleoli could help to establish the diagnosis. Three cases were observed in which the onset of myeloma was preceded by a long period of essentially unchanged M-component concentration. In these cases a sudden increase of M-component concentration was accompanied by an increase of mean nucleolar size of bone marrow plasma cells.
| 47,698
|
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