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751.
Egerton L. Pope 《CMAJ》1927,17(2):166-171
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Rhesus monkeys housed outdoors exhibit a distinct breeding season limited to the fall and winter months. Four groups of female rhesus monkeys, multiparous nonlactating (MNL; n = 8), multiparous lactating (ML; n = 6), primiparous lactating (PL; n = 3) and nulliparous first-time ovulators (N; n = 6) were studied to investigate the influence of age, parity, and social dominance rank on the parameters of the breeding season. MNL exhibited the longest season (146 days), and PL the shortest (70 days), with N (106 days) and ML (89 days) intermediate. PL females also had a significantly reduced percentage of normal ovulations compared to other groups. Neither body weight nor estimates of body fat were related to either the timing of the ovulatory season or the quality of ovulations within the season. Parity and social dominance rank were significantly related to the percentage of normal ovulations (r = 0.85), with low-ranking, primiparous females exhibiting the fewest normal ovulations. These data indicate that the presence of a suckling infant acts synergistically with environmental factors to determine the parameters of the breeding season. Furthermore, postpubertal females may be more responsive to those factors that terminate the breeding season, and some factor independent of body weight but associated with low social dominance rank and/or primiparity renders females less capable of normal luteal function during the breeding season.  相似文献   
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A mixture of enzymes (mycolase) capable of lysing yeast cell walls was prepared from culture filtrates of Physarum polycephalum. The enzymes present in mycolase included chitinase, beta-1,3-glucanases and exo-glycosidases. The pH optima of these enzymes were in the range 3.5-5.0 and they had low activities at pH 7.0. Mycolase produced spheroplasts from Candida pseudotropicalis and, unlike commercial enzyme preparations such as L1, chitinase, beta, 1,3-glucanase and beta-glucosidase, had some candicidal activity in vitro against C. pseudotropicalis and C. albicans. Mycolase potentiated the antifungal activity of amphotericin B against C. pseudotropicalis grown in shake flask culture but did not potentiate the antifungal activity of the antibiotic against similar cultures of C. albicans; indeed antagonism between mycolase and amphotericin B was sometimes observed with the latter yeast. Mycolase caused an approximately two-fold increase in the total and viable counts of cultures of C. albicans inoculated with stationary phase cells. These increases, which were observed within about 30 min, were attributed to mycolase inducing the premature release of viable buds from 'lag' phase cells. Mycolase also increased the rate at which C. albicans formed germ tubes when the yeast was cultured in a medium containing serum. Mycolase alone or in combination with amphotericin B did not appreciably enhance phagocytosis or intracellular killing of the yeasts by unstimulated mouse peritoneal macrophages. Studies on mice infected systemically with C. albicans showed that mycolase only slightly enhanced amphotericin B therapy.  相似文献   
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IntroductionComplications in rheumatoid arthritis (RA) seem less common than they were years ago. The prevalence and progression of anterior atlantoaxial subluxations (aAASs), vertical subluxations (VSs), subaxial subluxations (SASs), and associated cervical myelopathy in RA over the past 50 years were determined.MethodsA literature search was performed by using Medline-OVID/EMBASE, PubMed, and Scopus (from 1960 to June 21, 2014). Prevalence studies were included if the sample size was at least 100 or the prevalence/progression of cervical subluxations was reported. Study quality was assessed by using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. Prevalence of cervical subluxations was calculated for each study. Student’s t test and meta-regression were used to evaluate for significance.ResultsIn total, 12,249 citations were identified and 59 studies were included. The prevalence of aAAS decreased from 36% (95% confidence interval (CI) 30% to 42%) before the 1980s to 24% (95% CI 13% to 36%) in the 2000s (P = 0.04). The overall prevalence rates were 11% (95% CI 10% to 19%) for VS, 13% (95% CI 12% to 20%) for SAS, and 5% (95% CI 3% to 9%) for cervical myelopathy, and there were no significant temporal changes. Rates of progression of aAAS, VS, and SAS were 4, 6, and 3 lesions per 100 patients per year, respectively. The incidence of new or progressive cervical myelopathy was 2 cases per 100 patients with known cervical subluxations per year.ConclusionsSince the 1960s, only aAAS has decreased dramatically. It is still more than twice as common as VS or SAS. No temporal changes in the development of cervical myelopathy in affected patients with RA were noted. The progression rates of cervical subluxations and myelopathy were unchanged over time.  相似文献   
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