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41.
为探讨左心室造影功能成像的价值与限度,我们选择冠脉及左心室造影者38例行左室功能成像,观察左室壁运动情况并与节段法室壁运动定量分析比较。结果示左室收缩正常18例,其各节段EF值平均39%,节段性收缩减弱7例,无收缩3例,矛盾收缩4例,普遍性收缩减弱6例,病变节段的EF值平均5~19%,明显低于正常者(P<0.01)。结论:左室功能成像效果直观且客观,可作为室壁运动定量分析的一个重要补充。 相似文献
42.
维拉帕米灌注治疗前列腺术后膀胱痉挛性疼痛的临床疗效观察 总被引:15,自引:2,他引:13
为探讨前列腺术后膀胱痉挛性疼痛的药物治疗效果,将26例前列腺增生行耻骨上经膀胱前列腺摘除术后频繁发作膀胱逼尿肌无抑制性收缩导致膀胱痉挛性疼痛者,按随机抽样法分为两组,第1组15例接受维拉帕米膀胱灌注治疗,第2组11例作为对照,不用任何可能影响下尿中功能的药物。 相似文献
43.
44.
对液化气燃烧后室内空气污染进行了流行病学调查,结果显示,液化气燃烧可造成SO_2、NO_2、空气总悬浮颗粒物和总烃类的室内空气污染。小鼠接触三个月出现T淋巴细胞计数降低、睡眠时间延长、骨髓嗜多染红细胞微核率增加、肺组织匀浆Ames试验阳性率增高、雄性小鼠精子畸形率增加,并有明显的剂量-反应关系。对接触5年以上的人群调查发现,呼吸道、鼻和眼的自觉症状明显增加,咽炎、鼻炎、结膜炎患病率增高。人群尿液浓缩物Ames试验和外周血红细胞微核率检出阳性结果,可能与液化气燃烧废气中含有致突变污染物有关。 相似文献
45.
Six human cytochrome P450s expressed in HepG2 cells using vaccinia virus cDNA-directed expression, were used to study the biotransformation of caffeine and its metabolites. CYP1A2 alone was responsible for caffeine 3-demethylation and paraxanthine 7-demethylation; in addition, 1A2 catalysed virtually all reactions related to caffeine and its metabolites. The metabolic profile of caffeine biotransformation by CYP1A2 averaged 81.5% for paraxanthine, 10.8% for theobromine and 5.4% for theophylline formation. It remained quite uniform when caffeine concentrations were varied. The most striking finding was that CYP2E1 (the ethanol-inducible form) had major influences upon caffeine metabolism: in particular, it catalysed the formation of theophylline and theobromine from caffeine. Thus, the in vivo metabolite profiling of caffeine may reveal CYP2E1 activities in addition to the previously documented activities of CYP1A2, polymorphic N-acetyltransferase and xanthine oxidase. 相似文献
46.
观察了食饵性高血脂对新西兰兔血小板功能、纤溶系统和血液流变学的影响以及去纤酶的调节作用,并动态观察了指标的变化.结果发现,高血脂能引起兔的血小板数增加,粘附力增强,血液粘滞性增加,红细胞流动变慢,呈现高凝和低纤溶状态,且主动脉形成明显粥样斑块.去纤酶在降低血脂的同时,可明显降低血小板的粘附力,降低血液粘滞性,呈现低凝和高纤溶状态,其主动脉粥样斑块亦明显减轻和缩小.提示去纤酶既能降低血脂又能降低血粘稠度,促进纤溶,起到抗凝及防止血栓形成,抑制动脉硬化的形成和发展. 相似文献
47.
Anti-rat thymocyte antibody-induced injury of glomerular mesangial cells is characterized initially by lysis (1 h) and is followed by proliferation (beginning at 3 to 4 days), with resolution that can include a focal increase in mesangial matrix (by 28 days). Chronic administration (every 12 h) of heparin (anticoagulant or nonanticoagulant) resulted in a decrease in antibody-induced mesangial cell proliferation, which, in turn, was associated with a decrease in the size and number of areas of focal mesangial matrix increase. The effect could not be attributed to the effect of heparin on complement, to alterations in the small numbers of la-positive cells that characterize the lesion, or to binding of antibody to glomeruli. The beneficial effects of heparin in reducing mesangial cell proliferation, with a subsequent reduction in matrix increase, suggest that mesangial cell responses are a major element in the development of at least some forms of glomerulosclerosis. The possible mechanisms by which these effects of heparin may be achieved are discussed. 相似文献
48.
Chih-Hsin Tang Rong-Sen Yang Houng-Chi Liou Wen-Mei Fu 《Journal of bone and mineral research》2003,18(3):502-511
The skeletal extracellular matrix produced by osteoblasts contains the glycoprotein fibronectin (Fn), which regulates the adhesion, differentiation, and function of osteoblasts. Fn fibrillogenesis is involved in the process of bone mineralization. Bone morphogenetic proteins (BMPs) can be isolated from organic bone matrix and are able to initiate de novo cartilage and bone formation. In this study, the effect of BMP-4 on Fn fibrillogenesis in cultured rat osteoblasts was examined. BMP-4 enhanced Fn synthesis and extracellular Fn assembly in primary cultured osteoblasts. In addition, the extracellular assembly of Fn from exogenously applied soluble human Fn was also increased by BMP-4. It has been reported that alpha5beta1 integrin is related to Fn fibrillogenesis. The synthesis of both alpha5 and beta1 integrins was upregulated by BMP-4. Immunocytochemistry showed that the clustering of alpha5 and beta1 integrins was also increased by BMP-4. BMP-4 increased fibril formation of Fn and the adhesion of osteoblasts onto Fn matrix, which was inhibited by disintegrin triflavin and Gly-Arg-Gly-Asp-Ser (GRGDS) peptide. Phosphorylation of extracellular signal-regulated kinase (ERK) and focal adhesion kinase (FAK) was increased by BMP-4. Enhancement of extracellular Fn fibrillogenesis and the mRNA expression of beta1 integrin by BMP-4 were inhibited by ERK kinase (MEK) inhibitor PD98059. These results suggest that the enhancement of extracellular Fn fibrillogenesis by BMP-4 in cultured osteoblasts is related to the increase of the synthesis of Fn and clustering of alpha5 and beta1 integrins. ERK is involved in the signaling pathway of BMP-4 in regulating Fn fibrillogenesis in osteoblasts. 相似文献
49.
50.
Distinguishment of A 42 Capsomere Structure of Icosohedral Virion from A 32 One by Electron Microsco
DistinguishmentofA42CapsomereStructureofIcosohedralVirionfromA32OnebyElectronMicroscopeCnenBingying(陈丙莺);ZhouTong(周)(Departme... 相似文献