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Summary: Smooth muscle-associated contractile protein in human and experimental acute leukaemias. Cells from ten human myeloblastic leukaemias and from spontaneous rat myeloblastic and lymphoblastic leukaemias were examined by indirect immunofluorescence with human serum containing smooth muscle antibody. Strong positive cell outline staining of blast cells was seen in cryostat sections of rat leukaemic lymph nodes, spleen and liver. In cell smears of human and rat leukaemias, cell outline fluorescence was restricted to cells in close contact with each other. Membrane immunofluorescence tests of suspensions of viable leukaemic cells were negative. Specificity of the immunofluor-escent staining reaction was established by failure to obtain staining with normal serum, or with smooth muscle antibody serum neutralized by homogenates of smooth muscle or extracts containing actin derived from smooth muscle. These observations suggest that smooth muscle-associated microfilaments are present in leukaemic blast cells and that expression of the antigen is dependent on cell- cell contact. The presence of this antigen may facilitate leukaemic infiltration of tissues.  相似文献   
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Evidence that gamma-aminobutyric acid (GABA) and benzodiazepine receptors play a role in the inhibition of ACTH-cortisol secretion in humans has until now been drawn only from data indicating that sodium valproate, a GABA mimetic, and diazepam, a benzodiazepine, decrease hypothalamus-pituitary-adrenal (HPA) axis secretion in patients affected by pathological hypersecretion of the axis. Therefore, the present study investigated the effects, in the same healthy subjects, of sodium valproate or diazepam, on both basal and stress-stimulated concentrations of beta-endorphin (beta-EP), beta-lipotropin (beta-LPH) and cortisol. A single maximal dose of sodium valproate (400 mg) or diazepam (10 mg) did not significantly modify basal concentrations of beta-EP, beta-LPH and cortisol. On the other hand, in the same subjects, pretreatment with sodium valproate (20 mg X 3) or diazepam (10 mg X 2) blocked the increases in these hormones produced by hypoglycemic stress in all patients tested (p less than 0.01 vs. placebo at 45, 60 and 90 min after insulin injection), without affecting the decrease in blood glucose levels. The present data show that sodium valproate and diazepam inhibit stress-induced beta-EP, beta-LPH and cortisol secretion in humans, suggesting that endogenous GABA and benzodiazepine receptors participate in physiological mechanisms regulating the activity of the HPA axis.  相似文献   
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P Muller 《Phlébologie》1972,25(3):223-226
The etiopathogenesis of vascular complications of oral contraceptive treatment is discussed. Such complications are almost never seen in women treated with progestin preparations, even in very high doses, and occur primarily in women with histories of thromboembolism or varicoses. The occurrence of these complications in late pregnancy and the puerperium, when estrogen levels are particularly high, is also an argument pointing to estrogens as a responsible factor.  相似文献   
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BackgroundThough women increasingly make up the majority of medical-school and other science graduates, they remain a minority in academic biomedical settings, where they are less likely to hold leadership positions or be awarded research funding. A major factor is the career breaks that women disproportionately take to see to familial duties. They experience a related, but overlooked, hurdle upon their return: they are often too old to be eligible for ‘early-career researcher’ grants and ‘career-development’ awards, which are stepping stones to leadership positions in many institutions and which determine the demographics of their hierarchies for decades to come. Though age limits are imposed to protect young applicants from more experienced seniors, they have an unintended side effect of excluding returning workers, still disproportionately women, from the running.MethodsIn this joint effort by the European Society of Clinical Microbiology and Infectious Diseases, the Federation of European Microbiological Societies, the Infectious Disease Society of America, the International Society for Infectious Diseases and the Swiss Society for Infectious Diseases, we invited all European Congress of Clinical Microbiology and Infectious Diseases-affiliated medical societies and funding bodies to participate in a survey on current ‘early-career’ application restrictions and measures taken to provide protections for career breaks.RecommendationsThe following simple consensus recommendations are geared to funding bodies, academic societies and other organizations for the fair handling of eligibility for early-career awards: 1. Apply a professional, not physiological, age limit to applicants. 2. State clearly in the award announcement that career breaks will be factored into applicants' evaluations such that: ? Time absent is time extended: for every full-time equivalent of career break taken, the same full-time equivalent will be extended to the professional age limit. ? Opportunity costs will also be taken into account: people who take career breaks risk additional opportunity costs, with work that they did before the career break often being forgotten or poorly documented, particularly in bibliometric accounting. Although there is no standardized metric to measure additional opportunity costs, organizations should (a) keep in mind their existence when judging applicants' submissions, and (b) note clearly in the award announcement that opportunity costs of career breaks are also taken into account. 3. State clearly that further considerations can be undertaken, using more individualized criteria that are specific to the applicant population and the award in question.The working group welcomes feedback so that these recommendations can be improved and updated as needed.  相似文献   
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Several single nucleotide polymorphisms (SNPs) associated with type 2 diabetes mellitus (T2DM) have been identified, but there is little information on their role in populations at high risk for T2DM. We genotyped SNPs at 63 T2DM loci in 3,421 individuals from a high-risk American Indian population. Nominally significant (P < 0.05) associations were observed at nine SNPs in a direction consistent with the established association. A genetic risk score derived from all loci was strongly associated with T2DM (odds ratio 1.05 per risk allele, P = 6.2 × 10−6) and, in 292 nondiabetic individuals, with lower insulin secretion (by 4% per copy, P = 4.1 × 10−6). Genetic distances between American Indians and HapMap populations at T2DM markers did not differ significantly from genomic expectations. Analysis of U.S. national survey data suggested that 66% of the difference in T2DM prevalence between African Americans and European Americans, but none of the difference between American Indians and European Americans, was attributable to allele frequency differences at these loci. These analyses suggest that, in general, established T2DM loci influence T2DM in American Indians and that risk is mediated in part through an effect on insulin secretion. However, differences in allele frequencies do not account for the high population prevalence of T2DM.  相似文献   
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