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排序方式: 共有1774条查询结果,搜索用时 15 毫秒
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Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
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The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
7.
Gas-permeable lifecell tissue culture flasks give improved growth of Helicobacter pylori in a liquid medium. 总被引:3,自引:1,他引:2 下载免费PDF全文
Experiments were conducted to investigate the microaerobic culture of Helicobacter pylori in a liquid medium by using gas-permeable Lifecell tissue culture flasks. Growth in Lifecell tissue culture flasks was 1.2 to 1.6 log units greater than that in glass control bottles. These results were comparable to those reported by the use of gyrated media. 相似文献
8.
The characterization and pathological significance of gastric Campylobacter-like organisms in the ferret: a model for chronic gastritis? 总被引:6,自引:0,他引:6
Gastric campylobacter-like organisms (CLO) were isolated from gastric tissues removed at sacrifice from 17 mature ferrets; all animals were colonized, but no macroscopic mucosal lesions or histological features of chronic gastritis were seen. The isolates resembled Campylobacter pylori in many cultural and biochemical characteristics, and produced substantial urease activity, but there were sufficient differences from C. pylori to suggest that ferret gastric CLO represents a separate species. Comparison of human C. pylori and ferret gastric CLO may help to elucidate the pathogenicity of the former in patients with gastritis, and the ferret may serve as a useful animal model for the study of C. pylori infection. 相似文献
9.
R K Tompkins 《The Surgical clinics of North America》1990,70(6):1329-1339
The biliary surgeon in the 1990s must be familiar with all of the available techniques for the treatment of bile duct stones. Experience and judgment are important in the successful management of the individual patient with intrahepatic or extrahepatic stones. Knowledge of the nonsurgical methods of stone removal is important in the decision-making process. However, the biliary surgeon must resist the temptation to do less than a thorough removal of all stones at the operation lest the patient be subjected to additional procedures, which carry their own risks of morbidity and death. The goal should be to clear the stones from the biliary system with the fewest procedures offering the lowest morbidity and mortality risks to the patient. 相似文献
10.
Piglets infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV) are born severely immunocompromised. In this article we more closely examine the effects of in utero PRRSV infection on circulating and thymic T cell populations. Numbers of CD4+, CD8+, and dual-positive lymphocytes were quantitated in circulation and in the thymus during the 2 weeks following birth. At birth we found that the number of circulating lymphocytes was suppressed by 60%. Lymphocyte numbers were also suppressed by 42% at day 7, but by day 14 the number of lymphocytes had rebounded and was actually 47% greater than controls. At birth and day 7, a drop in the number of CD4+ cells could partially explain the suppression we observed, while the rebound in total lymphocyte numbers seen at day 14 was due to a nearly fourfold increase in the number of circulating CD8+ cells. As a result, the normal CD4+:CD8+ ratio of between 1.4 and 2.2 for neonatal pigs was reduced to 0.1-0.5. The thymuses of infected piglets were found to be 50% smaller than those of control pigs and were characterized by cortical involution and severe cortical depletion of thymocytes. Analysis of the population of thymocytes revealed that double-positive thymocytes were suppressed to a greater degree than either single positive subpopulation. In addition, we show that the number of thymocytes undergoing apoptosis was increased twofold in piglets infected with PRRSV. Taken together, these results help explain the dramatic immunosuppression observed in neonatal animals infected in utero with PRRSV. 相似文献