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21.
22.
V Kyle B Silverman A Silman H King N Oswald B Reiss B Hazleman 《BMJ (Clinical research ed.)》1985,291(6492):385-387
The aim of this study was to establish the incidence and prevalence of polymyalgia rheumatica/giant cell arteritis in general practice. Patients with this disorder, whether previously diagnosed or not, were ascertained by using a questionnaire administered by interview, and all received full clinical and laboratory assessment. A total of 579 patients aged 65 and over was seen, and 19 (33/1000) had been diagnosed or developed symptoms within the previous eight years. Thus the calculated annual incidence in those aged 65 and over was about 4/1000. The figures from this first large scale study of polymyalgia rheumatica/giant cell arteritis in general practice are much higher than those from studies carried out in hospital. The questionnaire was effective in both identifying known cases of polymyalgia rheumatica/giant cell arteritis and detecting new cases. As this is a treatable disorder, it is important that doctors become aware of how common it is in elderly people. 相似文献
23.
Human follicular fluid from healthy mature Graafian follicles and from pathologic ovarian cyst fluid was found to be inhibitory to progesterone-induced meiotic maturation of oocytes from the South African clawed toad, Xenopus laevis. Human follicular fluid but not human serum, collected from the same individuals, demonstrated a linear dose-response inhibition on the maturation of oocytes in the Xenopus assay system. These findings indicate that the human follicular and cyst fluids contain oocyte maturation inhibitor (OMI). This human OMI was inactivated when subjected to a boiling water bath for 2 min. The OMI action was shown to be reversible in its inhibitory action. The fact that OMI can act directly on the oocyte was demonstrated by its inhibitory action on maturation in defolliculated oocytes. The findings demonstrate that the inhibitory action of human OMI is not species-specific. Xenopus oocytes provide a simple, readily available, year-round bioassay material for testing follicular oocyte maturation inhibitor. 相似文献
24.
Richard B. Silverman A. Jabbar Muztar Mark A. Levy James D. Hirsch 《Life sciences》1983,32(24):2717-2723
The effects of intraperitoneal administration of (S)-4-amino-5-fluoropentanoic acid, a mechanism-based covalent inactivator of γ-aminobutyric acid transaminase (GABA-T), on whole brain GABA metabolism in mice were investigated. A dose-dependent and time-dependent irreversible inactivation of GABA-T was observed with a concomitant increase in whole brain GABA levels. The compound exhibited no nor time-dependent inhibition of glutamate decarboxylase (GAD), alanine transaminase, or aspartate transaminase (Asp-T). It was, however, a potent competitive reversible inhibitor of GAD and a weak competitive inhibitor of Asp-T. The chloro analogue, (S)-4-amino-5-chloropentanoic acid, was ineffective. 相似文献
25.
The identification and regionalization of four pituitary parenchymal cell types, gonadotrophs, mammotrophs, somatotrophs and thyrotrophs, were studied in the baboon (Papio cynocephalus) hypophysis using immunocytochemistry. The gonadotrophs were homogeneously distributed throughout the entire pars distalis. Both mammotrophs and somatotrophs predominate at the superior and inferior poles of the organ. The medial and anteromedial regions are populated by mammotrophs and thyrotrophs, while the lateral and posterior portions of the pars distalis contain large numbers of somatotrophs. 相似文献
26.
Positioning Flagellar Genes in Escherichia coli by Deletion Analysis 总被引:12,自引:10,他引:2
27.
Separation of a New Deoxyribonucleic Acid Polymerase from Vaccinia-infected HeLa Cells 总被引:5,自引:4,他引:1 下载免费PDF全文
HeLa cell deoxyribonucleic acid (DNA) polymerase was purified about 100-fold by sequential column chromatography on phosphocellulose, hydroxylapatite, and Bio Rex 70. A new form of DNA polymerase found in vaccinia virus-infected cells was separated from HeLa DNA polymerase by chromatography on diethylamino-ethyl cellulose. The new form was also purified approximately 100-fold in the same manner as the HeLa DNA polymerase. In addition to chromatographic differences, the two enzymes differed with regard to primer response, relative activity at high pH, inactivation by heat and p-chloromercuribenzoate, and inhibition by vaccinia antiserum. 相似文献
28.
Measurement of the weight of individual virus particles from untreated and antibody-treated populations was made by quantitative electron microscopy. The weight of antibody bound depended on the concentration of antibody in solution. One population of viruses exposed to an antibody concentration which resulted in 95% inhibition of hemagglutination showed a mass increase of 55%, corresponding to an absolute increase of 9.0 x 10-17 g in the median value. Another population, whose hemagglutination inhibition assay was 64%, showed a 39% increase in mass corresponding to an absolute median increase of 7.3 x 10-17 g. The larger viruses in each population bound a greater absolute amount of antibody than did the smaller ones, but the latter bound relatively more antibody in proportion to their mass. No cross-reactivity was found between the antibody to influenza A/PR8 and the influenza strain B/LEE. Influenza A/PR8 controls exposed to nonspecific gamma-globulin displayed a significant weight loss, at least in part owing to loss from the core, as judged from the electron micrographs. 相似文献
29.
Mutant male strains with an altered nucleic acid pump 总被引:3,自引:0,他引:3
30.
Activation of interferon-regulated, dsRNA-dependent enzymes by human immunodeficiency virus-1 leader RNA. 总被引:19,自引:0,他引:19 下载免费PDF全文
Human immunodeficiency virus-1 (HIV-1) leader RNA, which contains double-stranded regions due to inverted repeats, was shown to activate the dsRNA-dependent enzymes associated with the interferon system. HIV-1 leader RNA produced in vitro using SP6 RNA polymerase was characterized using probes for antisense and sense-strand RNA. The RNA preparation was free from significant levels of antisense RNA. HIV-1 leader RNA was shown to activate dsRNA-dependent protein kinase in a cell-free system from interferon-treated HeLa cells. Affinity resins, consisting of HIV-1 leader RNA covalently attached to cellulose, immobilized and activated dsRNA-dependent protein kinase and 2-5A-synthetase. HIV-1 leader RNA, therefore, may be a contributing factor in the mechanism by which interferon inhibits HIV replication. 相似文献