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51.
观察夺参碱作用于HepG2细胞后,光镜和电镜下细胞形态结构改变以及AFP、PCNA和分裂指数的变化。方法倒置显微镜下观察活细胞形态;光镜下观察Wright和苏丹Ⅲ染色的细胞形态和分裂指数;扫描和透射电镜观察细胞表面和内部超微结构改变;免疫组化和图像分析,检测AFP和PCNA。结果未用药细胞具有肿瘤细胞典型的形态特征,细胞的分裂指数为53.8%,胞浆内未见秀明颗粒和空泡,苏丹Ⅲ染色为阴性。;免疫组化  相似文献   
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In the past, a good bedside manner and nimble fingers were characteristics of a good doc. But in these cost cutting, profit-motivated days, hospital and health plans are now looking for physicians who can boost the bottom line. It's called "economic credentialing." Medical groups don't like it, and they're suing.  相似文献   
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Caspases as treatment targets in stroke and neurodegenerative diseases   总被引:34,自引:0,他引:34  
Apoptosis is one of the most exciting and intensely investigated areas of biology and medicine today. Cysteine proteases called caspases serve as the executioners of apoptosis, a form of cell suicide. Hypoxic/ischemic cell death proceeds in part, by apoptosis, particularly within the periinfarct zone or ischemic penumbra. During ischemia, activated caspases dismantle the cell by cleaving multiple substrates including cytoskeletal proteins and enzymes essential for cell repair. Strategies that inhibit caspase activity block cell death in experimental models of mild ischemia, and preserve neurological function. The therapeutic window for caspase inhibition is substantially longer than for glutamate receptor antagonists, and treatment combinations with both classes of drugs decrease ischemic injury and expand the treatment window synergistically. Hence, the caspases are now recognized as novel therapeutic targets for central nervous system diseases in which cell death is prominent. This article will review the evidence and the potential importance of caspase inhibition to cerebral ischemia and briefly summarize an emerging body of data implicating caspases in cell death accompanying neurodegenerative disorders.  相似文献   
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OBJECTIVES: We explore the policy implications of probabilistic sensitivity analysis in cost-effectiveness analysis by applying simulation methods to a decision model. METHODS: We present the multiway sensitivity analysis results of a study of the cost-effectiveness of vaccination against pneumococcal bacteremia in the elderly. We then execute a probabilistic sensitivity analysis of the cost-effectiveness ratio by specifying posterior distributions for the uncertain parameters in our decision analysis model. In order to estimate probability intervals, we rank the numerical values of the simulated incremental cost-effectiveness ratios (ICERs) to take into account preferences along the cost-effectiveness plane. RESULTS: The 95% probability intervals for the ICER were generally much narrower than the difference between the best case and worst case results from a multiway sensitivity analysis. Although the multiway sensitivity analysis had indicated that, in the worst case, vaccination in the 85 and older age group was not acceptable from a policy standpoint, probabilistic methods indicated that the cost-effectiveness of vaccination was below $50,000 per quality-adjusted life-year in greater than 92% of the simulations and below $100,000 in greater than 95% of the simulations. CONCLUSIONS: Probabilistic methods can supplement multiway sensitivity analyses to provide a more comprehensive picture of the uncertainty associated with cost-effectiveness ratios and thereby inform policy decisions.  相似文献   
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Despite the growth in primary care-based women's health centers, little is known about the characteristics of women's health patients and the quality of care provided in women's health centers versus traditional practices. Our objective was to compare a women's health practice and a general internal medicine practice on issues of care during menopause. A cross-sectional survey was administered simultaneously to patients aged 50-70 and their primary care physicians in a women's health practice and an affiliated general internal medicine practice. The survey asked patients about health behaviors, past and current hormone use, menopausal symptoms, and attitudes about menopause. Physicians were asked to estimate their patients' attitudes. Patients in women's health practices were younger, more likely to be smokers, and more likely to have had a prior hysterectomy. Women's health patients were somewhat more likely to report concerns related to menopausal symptoms. Women's health patients and patients attending the general internal medicine practice reported similar rates of past or current use of hormone therapy, after adjusting for prior hysterectomy and age. Physicians in women's health and general medicine were similar in their ability to estimate their patients' attitudes. In the general internal medicine practice, female physicians tended to better estimate their patients' attitudes than their male colleagues. Patients seeking care in a women's health practice differed in symptoms and concerns about the menopause compared with patients in a traditional primary care setting. Physicians' understanding of patients' menopausal concerns did not differ between the two practices. However, there may be gender differences in physicians' understanding of patients' concerns.  相似文献   
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