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排序方式: 共有383条查询结果,搜索用时 15 毫秒
1.
A case of blunt injury to the abdominal aorta is presented. A deceleration injury with seat-belt compression caused dislodgement of atheromatous fragments as emboli from an atherosclerotic aorta. Atherosclerosis is common, and the compulsory wearing of seat-belts may make this injury more frequent.  相似文献   
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In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
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Low-artifact intravascular devices: MR imaging evaluation   总被引:2,自引:0,他引:2  
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible.  相似文献   
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There is limited evidence that inhibition of the activity of the protease calpain I reduces inflammation. Here we investigate the effects of calpain inhibitor I in animal models of acute and chronic inflammation (carrageenan-induced pleurisy and collagen-induced arthritis). We report here for the first time that calpain inhibitor I (given at 5, 10, or 20 mg/kg i.p. in the pleurisy model or at 5 mg/kg i.p every 48 hours in the arthritis model) exerts potent anti-inflammatory effects (eg, inhibition of pleural exudate formation, mononuclear cell infiltration, delayed the development of the clinical signs and histological injury) in vivo. Furthermore, calpain inhibitor I reduced (1) the staining for nitrotyrosine and poly (ADP-ribose) polymerase (immunohistochemistry) and (2) the expression of inducible nitric oxide synthase and cyclooxygenase-2 in the lungs of carrageenan-treated rats and in joints from collagen-treated rats. Thus, prevention of the activation of calpain I reduces the development of acute and chronic inflammation. Inhibition of calpain I activity may represent a novel therapeutic approach for the therapy of inflammation.  相似文献   
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对发展中国家改善用药的10点建议   总被引:2,自引:0,他引:2  
唐镜波  龚丽娴 《中国药师》2005,8(10):865-868
WHO建议改善药品管理的工作要在国家药物政策保障之下.在许多国家,执行国家药物政策的机制是实施国家基本药物计划,其要点是强调公共领域的药品选择、采购、流通与使用的合理性.不适当的处方使医疗质量降低并导致资源浪费.本文以探讨在国家药物政策范畴内鼓励更合理地使用药品的问题为重点,在已有证据的基础上,详细阐明基本药物计划内容中的合理用药问题.本文评述了在发展中国家改善用药状况的有效策略及最新知识,并为决策者与管理者提出达到改善用药目标的建议.  相似文献   
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以乙型肝炎病毒为载体的基因治疗研究   总被引:6,自引:1,他引:6  
目的 探讨乙型肝炎病毒(HBV)作为肝靶向性基因治疗载体的可能性。方法 用外源报告基因绿色荧光蛋白(GFP)取代HBV S基因读码框构建重组HBV载体,通过脂质体转染HepG2细胞,荧光显微镜下观察外源基因的表达,半巢式聚合酶链反应(PCR)检测细胞核内HBV 共价闭合环状DNA构型,常规PCR和Southern杂交检测上清液重组病毒DNA。结累 携带外源基因GFP的重组HBV载体能够在肝细胞内表达外源蛋白,此重组载体为复制缺损型,单独转染后不能在肝细胞包装与复制,在缺失包装信号ε的辅助HBV质粒下可被包装成携带外源基因的成熟重组HBV颗粒并分泌到胞外。结论 HBV可被改造成肝靶向性基因治疗载体。  相似文献   
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