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The goals of this study were to determine the effect of the nonionic detergent, Triton X-100, on the recovery of acrosin in the clinical assay (Kennedy et al, 1989), since previous investigations have used higher concentrations for acrosin extraction from spermatozoa; and to establish the minimal acrosin activity in fe...
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The secretion and clearance of immunoactive and bioactive follicle-stimulating hormone (FSH) in healthy young men (N = 10) and elderly men (N = 7) during blockade of endogenous sex steroid hormones with tamoxifen, an antiestrogen, and flutamide, an antiandrogen, was investigated. To this end, subjects underwent blood s...
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Senior nursing students (N = 505) attending 13 schools in the NY metropolitan area were administered a questionnaire to assess their beliefs about the importance of health promotion behaviors to the average person. Respondents rated 23 health promotion practices on a Likert scale. The five most important items concerne...
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The care of chronic wounds has become a major health issue in developed countries because of their increasingly elderly populations. There is hope that progress made in understanding and producing growth factors will lead to their successful use to induce faster and better healing of chronic wounds. This report will di...
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Xeroderma pigmentosum is a rare recessive disease with sun sensitivity, increased freckling and defective DNA repair. Xeroderma pigmentosum patients have more than a 1000-fold increased risk of developing skin cancer including basal cell carcinoma, squamous cell carcinoma and melanoma. We studied chemoprevention of new...
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Desmoplakins (DPs) I and II are two major related proteins located in the desmosomal plaque where they have been proposed to play a role in attaching intermediate filaments (IF) to the inner cell surface. The predicted amino acid sequence of DP was obtained by analysis of overlapping cDNA clones. Computer-aided analysi...
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1. A two-microelectrode voltage clamp was used to determine the effects of n-butanol, n-hexanol, n-octanol, n-decanol and methyl hexanoate on a transient potassium (IA) current in identified Helix aspersa neurones. Experiments were carried out at a temperature of 10-12 degrees C. 2. Each n-alkanol reversibly reduced th...
United Kingdom
1. Single channel recording techniques were used to study the ion channel openings resulting from activation of N-methyl-D-aspartate (NMDA) receptors by the agonist glutamate. Patches were from cells acutely dissociated from adult rat hippocampus (CA1). Channel activity was studied at low glutamate concentrations (20-1...
United Kingdom
1. The transfer of albumin between the blood and the cerebrospinal fluid (CSF) has been investigated in neonatal (3 days old) and juvenile (20 days old) rats. At both stages of postnatal development, all of the albumin present in the CSF can be accounted for by transfer from the blood. Thus it is unlikely that in situ ...
United Kingdom
1. The actions of 5-hydroxytryptamine (5-HT) and noradrenaline (NA) on the membrane properties of facial motoneurones in slices from the adult rat brainstem in vitro were examined using intracellular recording techniques. 2. In voltage clamp recording, hyperpolarizing voltage steps (> 20 mV), from holding potentials at...
United Kingdom
1. The extent to which vasodilator responses to electrical stimulation of the sympathetic innervation, in the submandibular gland of the cat, depend upon release of endothelium-derived relaxing factor (EDRF) within the gland has been investigated in anaesthetized cats given N-nitro-L-arginine methyl ester (L-NAME) whic...
United Kingdom
1. The pH dependence of a chloride conductance in the apical membrane of rat duodenal enterocytes was examined. 2. A stepwise reduction of both internal and external pH from 7.4 to 6.8 resulted in a significant stimulation of 36Cl flux driven by an inside-positive membrane potential. 3. A stepwise reduction in pH had n...
United Kingdom
1. We investigated the distribution and characteristics of motor pathways to individual smooth muscle cells activated by electrical stimulation of either, single nerves which enter the tracheal plexus (inlet nerves), or a longitudinal nerve trunk (LNT) located near the entrance of an inlet nerve into the plexus. Excita...
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Propetamphos [(E)-1-methylethyl 3-[[(ethylamino)methoxyphosphinothioyl]oxy]-2-butenoate], the active ingredient in Safrotin, is an organophosphate developed by Sandoz, Ltd. (Switzerland) as an insecticide (1). Although metabolism of propetamphos has been previously investigated (2,3), there is no pharmacokinetic data a...
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The bioactivation of 7-hydroxymethyl-12-methylbenz[a]anthracene (HMBA) to an electrophilic sulfuric acid ester metabolite has been shown to be catalyzed by rat liver bile acid sulfotransferase I (BAST I). The sulfation and activation of HMBA by BAST I was determined by the ability of sulfated HMBA to form DNA adducts. ...
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This study was designed to evaluate the relative response of myocardial efficiency to reduced oxygen supply (hypoxia and ischemia) in immature and mature isolated rabbit hearts. Hearts were subjected to either 15 min of hypoxia (60% or 30% O2) or reductions in coronary flow to 75%, 50%, 25%, and 15% of basal flow follo...
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Sympathetic innervation is known to increase heart size in the immature animal, yet the mechanism for this growth remains to be established. This comparative study stereologically quantified the volume of cultured neonatal ventricular myocytes with and without in vitro sympathetic innervation to isolate the mechanisms ...
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In glycogen storage disease type III (glycogen debranching enzyme (DE) deficiency), the activities of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase may be strikingly elevated during childhood but are low during adult life. To determine the pattern of the elevated serum enzyme acti...
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Bone marrow transplantation has been undertaken with encouraging results as therapy for a wide variety of lysosomal storage diseases. We report a case of Niemann-Pick disease Type IA in which, despite the presence of only mild hypotonia with depressed reflexes, the clinical course of the disease appeared to be only sli...
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The role of molecular biology in understanding structure/function relationships as well as the influence of metabolic processes on host nutrition is becoming increasingly important. Not only is this field having a major effect in elucidating the detailed structure of nutritionally important enzymes but it is also allow...
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In our work evaluating the antioxidant properties of a number of cardiovascular drugs, we have emphasized the importance of lipophilicity as a property contributing to antioxidant potency. Thus, the dihydropyridine calcium channel blockers and propranolol, one of the most lipophilic beta-blockers, were found to exhibit...
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The first intron of the human Pro alpha 1(I) collagen gene contains an orientation-dependent enhancer composed of both positive and negative cis-acting elements involved in the transcriptional regulation of this gene. Deletion of a 360 bp Sau 3A intronic fragment spanning nucleotide +494 to +854 (S360) resulted in dram...
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There is a complex collagen network in the heart. Various components have been identified and generally on the basis of form and position some functions have been ascribed to one or another of these components. Since the various components all appear to be connected in a hierarchial network of some type assigning funct...
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Previously we have measured rapid-velocity vergence responses to targets at different distances that provided no disparity or accommodative stimulation. To evaluate the possibility that this rapid-velocity vergence occurs during saccades, the latencies of eye movement between two long dim luminous rods were compared un...
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Three visual tests were administered to a group of 15 amblyopic children, 15 adult amblyopes and two age-matched control groups, each of 20 subjects. Test results comprised visual acuity for recognizing high contrast letters presented in line (i.e. Snellen) format, isolated-letter format and repeat-letter format. The c...
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Many investigations have attempted to demonstrate a relationship between sustained near-vision and the aetiology of environmentally-induced myopia, but it remains unclear whether myopic development relates to the actions of either accommodation or vergence. The present study investigated the effect of varying the dispa...
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The distinctions between diagnostic classification of schizophrenia, the description of the characteristics and course of schizophrenia, and measurement of its severity are discussed. There is confusion among these three categories by both researchers and clinicians. The causes for this confusion are discussed, and it ...
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The aromatic amine ortho-toluidine has been recognized by IARC as an animal carcinogen for the past decade. Three recent epidemiological studies of worker populations have now implicated this chemical as a human bladder carcinogen. In a study by E. Ward, A. Carpenter, S. Markowitz, D. Roberts, and W. Halperin ((1991), ...
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Ethical considerations in a cancer phase I trial require a design allowing determination of the maximum tolerated dose with a minimum number of patients treated at low ineffectual or high overly toxic doses. It would also be advantageous to complete the phase I trial in as short a period of time and with as few patient...
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Adult Schistosoma mansoni from experimentally infected mice and Fasciola hepatica recovered from ovine livers post mortem were analyzed for free and conjugated ecdysteroids by radioimmunoassay, high-performance liquid chromatography monitoring fractions by radioimmunoassay, and by capillary gas chromatography/mass spec...
United Kingdom
The discovery of nontraditional inheritance and of developmental gene families common to all metazoans has revolutionized research on human congenital anomalies. The most gratifying results of these new concepts are summarized in Table 5: several human syndromes have already been related to their causative genes. Class...
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Sterol auxotrophic strains of Saccharomyces cerevisiae were grown and allowed to conjugate on media supplemented with various sterols. The mating efficiency of the auxotrophs is perturbed by the replacement of the normal yeast sterol, ergosterol, with other sterols. After 4 h of mating, cells grown on ergosterol exhibi...
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We have determined the structure of the allantoin permease (DAL4) gene of Saccharomyces cerevisiae. The gene putatively encodes a hydrophobic protein with a M(r) of 71,755. It possesses the alternating hydrophobic-hydrophilic regions similar to those found in many other integral membrane proteins. The most striking fea...
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A complex, cascaded neural network designed to predict the secondary structure of globular proteins has been developed. Information about the local buried-unburied pattern and the average tendency of the particular types of amino acids to be buried inside the globule were used. Nonspecific information about long distan...
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A solid-phase method for the purification of the single-stranded DNA molecules produced in enzymatic sequencing reactions has been developed. A primer oligonucleotide is synthesized containing a biotin moiety at an internal position. This primer is utilized in enzymatic extension reactions, and the resulting products a...
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252Cf plasma desorption mass spectrometry has been used in the characterization of more than 100 synthetic porphyrins ranging in mass from 614 u for tetraphenylporphyrin to over 2000 u for some porphyrin model systems. In virtually every case, 252Cf plasma desorption mass spectrometry yielded an intense ionized molecul...
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Interleukin-6 (IL-6) is a multifunctional cytokine which has been suggested to function as an autocrine mitogen in psoriatic epidermis. We report here the results of several experiments designed to further examine this hypothesis. Blot hybridization was unable to detect 1.3 kb IL-6 transcripts in RNA extracted from nor...
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The results of the accompanying electrophysiological study of the cloned Na+/glucose cotransporter from small intestine (Parent, L., Supplisson, S., Loo, D.D.F., Wright, E.M. (1992) J. Mémbrane Biol. 125:49-62) were evaluated in terms of a kinetic model. The steady-state and presteady-state cotransporter properties are...
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We examined the relationship between the dates of births of schizophrenic patients admitted to hospitals for the first time in England and Wales between 1970 and 1979, and the occurrence of influenza epidemics between 1939 and 1960. Our results indicate that exposure to influenza epidemics between the third and seventh...
United Kingdom
Reports of fatal or near-fatal anaphylactic reactions to foods in children and adolescents are rare. We identified six children and adolescents who died of anaphylactic reactions to foods and seven others who nearly died and required intubation. All the cases but one occurred in one of three metropolitan areas over a p...
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The gene for the human macrophage mannose receptor (MRC1) has been characterized by isolation of clones covering the entire coding region. Sequence analysis reveals that the gene is divided into 30 exons. The first three exons encode the signal sequence, the NH2-terminal cysteine-rich domain, and the fibronectin type I...
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In an effort to characterize genes expressed in the cerebellum, we have isolated two cDNA clones, H11B (D16S286) and 507 (D5S344), that hybridized to a cerebellar cDNA probe. Using a panel of human-rodent somatic cell hybrids, cDNA clone H11B was mapped to human chromosome 16, and clone 507 was mapped to human chromoso...
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The course of intracellular pH (pHi) was followed in superfused (36 degrees C) single glomus (type I) cells of the freshly dissociated adult rat carotid body. The cells had been loaded with the pH-sensitive fluorescent dye 2',7'-(2-carboxyethyl)-5 (and -6)-carboxyfluorescein. The high K(+)-nigericin method was used for...
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Our understanding of the adverse effects of early child physical and sexual abuse has developed to a point where there is need to elucidate the processes by which various developmental outcomes occur. Limited variability on key measures of family stress and in youths' drug use, other delinquent behavior and abuse histo...
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The current study presents the results of a needs assessment of 141 women exiting an emergency shelter for women with abusive partners. Extensive in-person interviews were conducted. Results indicate that battered women need numerous community resources upon their shelter exit, including legal assistance, employment, a...
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Epidermal growth factor (EGF) protects gastric mucosa against acute injury produced by a variety of damaging agents, but the mechanism of its protective action is not clear. Since the surface epithelial cells (SEC) are important component of gastric mucosal defence, we studied whether EGF may directly protect isolated ...
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Patients with bulimia nervosa frequently have problems with alcoholism and other substance abuse. The goal of this study was to assess whether this relationship between eating abnormalities and substance abuse extends to subthreshold levels of dieting and substance use. A self-administered questionnaire assessing dieti...
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Although high-risk situations have been identified for alcoholism, opiate abuse, and smoking, further research is needed to identify high-risk situations for cocaine abuse. A 233-item Cocaine High-Risk Situations Survey was developed based on a comprehensive literature review and was administered to 179 cocaine users i...
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The effect of 72 h fasting, nutritional therapy of fasted rats, and acute and chronic glucocorticoid treatment on the yield of histone H1 from rat hind limb muscles was determined. Fasting significantly enhanced the extractability of muscle H1. The effect of treating starved rats with glucose alone, or with glucose sup...
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A proposed convention sets zero pressure at atmospheric pressure at the level of the surface supporting the supine patient and takes the cm of water as the unit of measurement. This ensures that measurements made in different clinics will be comparable. Statements about 'higher' and 'lower' pressures, in different pati...
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Bereaved spouse caregivers (N = 65) studied during the time they were giving care were contacted a minimum of 6 months following the first interview to determine if perceptions of the demands of caregiving had changed over time. Thirty-one participated in the second phase of the study. Although managing the physical ca...
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Monoclonal antibodies against the high affinity tyrosine kinase Fibroblast Growth Factor (FGF) receptor may help define receptor epitopes involved in FGF binding and signal transduction which mediate coronary and tumor angiogenesis (the development of blood vessels). Monoclonal antibodies against the FGF receptor were ...
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Histochemical, immunohistochemical, histological and morphometric properties of bupivacaine-injected rat skeletal muscle were studied at times spanning the complete course of degeneration and regeneration to establish when, if ever, 'normality' is reached. This was achieved in a sequence of measurements made on the sam...
United Kingdom
Previous experiments in rat incisors indicate that the odontoblasts form an impermeable barrier which prevents fluid movement between pulp and dentine. The permeability of the odontoblast layer has now been investigated in pig molars which are more analogous to human teeth. The heads and necks of anesthetised piglets w...
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The anti-HIV activities of two new polyanionic polymers (AM 242 and AM 612) were investigated in cell culture-based and biochemical antiviral assays. These compounds inhibited the reverse transcriptases from HIV-1 and HIV-2, using enzyme purified from virions and either a ribosomal RNA or gapped duplex DNA as the templ...
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The modulatory effects of serotonin on T-cell activity were investigated. T-cell blastogenesis of normal spleen cells was slightly stimulated by the addition of low doses (1 and 10 ng/ml) of the inducer of serotonin release, fenfluramine. In contrast to the stimulatory effects of low doses of fenfluramine, high doses o...
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Study objectives were to characterize the clinical syndrome of chronic idiopathic esophageal ulceration in patients with acquired immunodeficiency syndrome (AIDS), to determine the extent of local human immunodeficiency virus (HIV) infection, and to evaluate the effect of corticosteroid therapy upon symptoms and healin...
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The free fatty acids of the Mediterranean opisthobranch Haminaea templadoi were isolated and characterized, revealing the presence of the new 10,15-eicosadienoic acid [1] and several unusual cis delta 6 monoenoic acids, such as (Z)-6-tetradecenoic acid, (Z)-6-pentadecenoic acid, and (Z)-6-heptadecenoic acid. These resu...
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The probability of continuation of a particular nonsteroidal antiinflammatory drug (NSAID) over 5 years was estimated for 1,775 courses taken by 532 patients with rheumatoid arthritis treated in 7 rheumatology private practices. Similar results were seen for 15 different NSAID--48% of courses were continued at 12 month...
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The probability of continuation of 1,077 courses of 2nd line drugs taken by 532 patients with rheumatoid arthritis treated in 7 rheumatology private practices was examined. This probability was that 50% of courses were continued over 10 months for oral gold, 20 months for hydroxychloroquine, 21 months for penicillamine...
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A longitudinal sample of patients with rheumatoid arthritis (RA) from Santa Clara County, CA was analyzed. Severity was measured with the Disability Index from the Health Assessment Questionnaire (HAQ). First, 6 cohorts were created of women and men with 0 to 10, > 10 to 20, and > 20 years of duration of illness in 198...
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Aaron Antonovsky's Sense of Coherence (SOC) questionnaire with its 3 subscales is designed to measure strengths within individuals that allow them to survive in the face of extreme stresses, including chronic illness. We administered the SOC to 1333 patients with rheumatic disorders. Although the instrument had high al...
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To confirm previous studies that have identified knee osteoarthritis as the principal correlate of poor outcomes after arthroscopic partial meniscectomy (APM), we considered a range of other preoperative characteristics using multivariable analyses to control for confounding variables.
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We examined the associations of sociodemographic variables, health behaviors, health status and psychological well being with radiographic knee osteoarthritis (OA) and self-reported knee pain for 4056 US adults aged 45-74 years. Among persons with or without knee OA known correlates of radiographic knee OA (age, sex, r...
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Our randomized double blinded comparison of acetaminophen versus analgesic and antiinflammatory doses of ibuprofen in the treatment of 182 subjects with knee osteoarthritis (OA) systematically evaluated soft tissue tenderness and joint swelling. Improvement in these signs of joint inflammation was associated with lesse...
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Plasma was obtained from 10 human subjects at various intervals after administration of two rapid doses of cocaine, either intravenously or by smoking, and multiple doses by smoking and intravenously. The plasma was analyzed for COC and its metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME). Plasma conce...
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In a subdivided population, genetic drift affects variation between groups, and thus it can have an important effect on the outcome of evolution (Wright, 1978). The rate of genetic drift is determined, in part, by the behaviour of population members. This paper presents three mathematical models in which behavioural tr...
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The partitioning of chromosomes into daughter cells during the division of Escherichia coli is non-random. As a result, the chromosome containing the older template DNA strand has a higher probability of segregating toward the old cell pole than toward the new cell pole. The numerical value of this probability is a fun...
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Cellular volume regulation following swelling in hypo-osmotic phosphate-buffered saline (PBS) and ATP and phosphocreatine concentrations of cells incubated in iso-osmotic or hypo-osmotic PBS were measured in primary cultured rat cerebral astrocytes exposed for 30 min to NH4Cl, salicylate, hexanoate, octanoate, and/or d...
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Using dual tracer quantitative digital autoradiography and iodoantipyrine (IAP), we compared local cerebral blood flow (LCBF) measurements using two different infusion times within the same animal. Rats were given concurrent infusions of 14C-IAP and 123I-IAP; one tracer was administered over 20 seconds and the other ov...
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We report a patient with regional enteritis and short bowel syndrome who has been treated with home parenteral nutrition for 19 years, during 10 of which he used a single Broviac central venous catheter. The catheter finally required replacement because of progressive lumen occlusion, which was presumed to be caused by...
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I have herein discussed two gene-enzyme families in maize whose protein products participate to purge toxic oxidants from cells, and are thus of importance to all aerobic organisms. We have demonstrated that plant mitochondria import precursor proteins (i.e., preSOD-3) in a manner analogous to other eukaryotic cells. T...
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Interest in xenotransplantation has dramatically increased in the past 4 years, focusing on the potential use as donors of distantly related animals such as pigs (discordant xenografts). The major barrier is hyperacute rejection. The mechanisms responsible for this rejection include: specific reaction of the recipient'...
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Chronic (24-month) inhalation exposure to 5 or 10 ppm allyl glycidyl ether (AGE) induced nasal lesions in Osborne-Mendel rats and B6C3F1 mice. Inflammation, degeneration, regeneration, metaplasia, hyperplasia, and neoplasia were observed in the nasal mucosa. Squamous metaplasia and hyperplasia of the respiratory epithe...
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A 27-year-old white man with no significant risk factors for coronary artery disease presented with a 9-month history of progressive impotence, gynecomastia, lower extremity paresthesias, and extensive myocardial infarction and subsequently developed ulcerative proctitis. A diagnosis of POEMS syndrome was made based on...
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Questions about alcohol consumption, social and work contexts, and negative consequences related to alcohol use were asked of forty-nine academics, 27 physicians, 15 attorneys, and 169 business women. The majority of the women were light drinkers and their drinking does not appear to be accompanied by negative conseque...
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The Life Satisfaction Index (LSI) continues to be one of the most frequently used measures of well-being in social gerontology. Discrepancies in the operational use of the LSI, however, have made comparisons across studies difficult. Few studies have incorporated examination of the effect of gender/race interactions on...
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Entrapment of purified alpha-hemoglobin chains within normal erythrocytes resulted in structural and functional changes very similar to those observed in human beta thalassemic erythrocytes (Table 1). Membrane proteins and reactive thiol groups were decreased in a pattern similar to that observed in vivo in beta thalas...
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CD4+ Th cells and their derived cytokines play an important role in the regulation of IgA responses in the mucosal immune system. Th1 and Th2 cells induce different Ig isotype and IgG-subclass responses. Further, cytokines produced by Th2-type cells (e.g., IL-5 and IL-6) have been shown to induce PP sIgA+ B cells to se...
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The IgA effector sites such as the salivary glands and the intestinal tract contain several distinct T cell subsets which possess unique biologic characteristics. Freshly isolated CD3+ T cells from the salivary glands, the LP region of the small intestine and IELs all harbor T cells which spontaneously produce Th1 (IFN...
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The selective induction of antibodies in external secretions and mucosal T cell-mediated immunity are desirable for the prevention of various systemic as well as predominantly mucosa-restricted infections. An enormous surface area of mucosal membranes is protected primarily by antibodies that belong, in many species, t...
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In this brief review, emphasis was placed on the effectiveness of liposomes as carriers/vehicles of soluble antigens and as adjuvants for use in oral vaccine development. Evidence was provided that oral administration of antigen in liposomes resulted in a mucosal response which was higher than that obtained when the or...
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In the 15 years since the last major NIH conference that dealt with anti-caries vaccines, we have learned much. Certainly, whole bacteria or bacterial fractions may not be proper immunogens due to the possibility of inducing tissue cross-reactivity. Our own experience (van de Rijn et al., 1976) illustrates that pitfall...
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Recently, there has been an increasing interest in the involvement of adenosine as a mediator of allergic asthma. In the present study, we have employed an allergic rabbit model to study the airway responses to adenosine. The rabbit litter mates were injected i.p., within 24 h of birth, with ragweed pollen extract to p...
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Nerve growth factor (NGF) inhibited cellular DNA synthesis of rat T9 anaplastic glioma cells in a dose-dependent manner in the range of 0.5-5 micrograms/ml. Oxidation of 2 to 3 tryptophan residues of NGF, which had been known to destroy biological and immunological activity, greatly diminished its inhibitory effect on ...
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The sialidase from Salmonella typhimurium LT2 was characterized by using photoaffinity-labelling techniques. The well-known sialidase inhibitor 5-acetamido-2,6-anhydro-3,5-dideoxy-D-glycero-D-galacto-non- 2-enonic acid (Neu5Ac2en) was modified to contain an amino group at C-9, which permitted the incorporation of 4-azi...
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The infrarenal abdominal aorta is a common site for clinically significant atherosclerosis. As has been shown in other susceptible locations, vessel geometry, flow division rates, and pulsatility may result in hemodynamic conditions which influence the preferential localization of disease in the abdominal aorta segment...
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Cage allocation designs for rodent carcinogenicity experiments are discussed and presented with the goal of avoiding dosage group biases related to cage location. Considerations in selecting a cage design are first discussed in general terms. Specific designs are presented for use in experiments involving three, four, ...
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An accurate three dimensional computer reconstruction of microscopic biological objects or distribution of molecules identified on serial sections must solve two major problems: 1) the alignment of sections using adequate extrinsic references (fiducial markers); 2) the impossibility of observing these references and th...
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The tooth organ provides a model for discrete patterns of morphogenesis over short periods of developmental time. Studies were designed to test the hypothesis that endogenous epidermal growth factor (EGF) functions to regulate multiple cusp molar tooth morphogenesis during embryonic mouse development. The relative leve...
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Brain capillary endothelium has a high density of the GLUT-1 facilitative glucose transporter protein. This is reasonable in view of the brain's high metabolic rate for glucose and its isolation behind unique capillaries with blood-brain barrier properties. Thus, the brain endothelium, which constitutes less than 0.1% ...
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During development different energy substrates are available to cells in brain in plentiful supply. The metabolic environment, which is dictated by the milk diet rich in fat, ensures that substrates in addition to glucose are available as fuels. Some substrates serve readily as primary fuels for respiration, whereas ot...
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CNS tissue is well known to have large energy requirements. However, because of the difficulty of measuring rates of energy usage, relatively little is known about which cell types and which neurophysiological functions are the principal energy users. In experiments performed on rabbit retina in vitro, it was possible ...
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Putative roles of glycolytic and oxidative metabolism in the removal of potassium ion from the extracellular space were examined in rat cerebral cortex. In response to direct electrical stimulation of the cerebral surface, the activity of extracellular potassium ion (Ko+) transiently increased. Inhibition of glycolysis...
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The rapid changes in brain extracellular ion concentrations that occur with anoxia are important in understanding the pathophysiology of anoxic-ischemic brain injury. While previous studies have focused on the ionic changes that occur in gray matter areas of the brain, white matter (WM) is also damaged by anoxia. We de...
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Intra- and extra-cellular concentrations of calcium were measured in hippocampal neurons of areas CA1 and CA3 during 8 min ischaemia and short-term (up to 60 min) recovery. During an ischaemic insult, [Ca2+]i increased progressively and [Ca2+]e decreased. There were large interneuronal differences, although, in general...
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Potassium is tightly regulated within the extracellular compartment of the brain. Nonetheless, it can increase 3- to 4-fold during periods of intense seizure activity and 10- to 20-fold under certain pathological conditions such as spreading depression. Within the central nervous system, neurons and astrocytes are both...
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Intracellular pH can be measured quantitatively in rat brain in vivo and in vitro using spectrophotometric detection of the vital dye neutral red. This method preserves spatial information and is compatible with microhistochemistry. The intracellular pH indicated by this method is in close agreement with that indicated...
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Microspectrofluorometry was used to study the regulation of intracellular pH (pHi) in 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF)-loaded astrocytes and the neuroblastoma-glioma cells of the NG 108-15 line. The cells rapidly regulated pHi during an acid transient induced by an NH4+ prepulse. This regulatio...
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The tetramethylammonium (TMA+) method for measuring the volume fraction and tortuosity of brain extracellular space is presented in detail. The temporal and spatial distribution of TMA+ in the extracellular space following iontophoresis or pressure microinjection is described by suitable equations and illustrated with ...
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