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121.
妊娠高血压患者血浆中降钙素基因相关肽的测定及其临床意义 总被引:2,自引:0,他引:2
本文测定了30例正常育龄妇女,28例正常妊娠以及36例妊娠征患者血浆中降钙素基因相关肽的水平,结果发现,轻度妊高生与正常妊娠相比,血浆中CGRPK是有下降但不显著(P〉0.05)。中重度妊高征与正常妊娠相比,差异有非常显著性,因此推测,妊娠状态下血浆中降钙素基因相关肽的减少可能是妊娠高血压症产生的重要原因之一。 相似文献
122.
National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training. 相似文献
123.
目的:探讨缺血预处理(IPC)是否对缺血/再灌注(I/R)脑细胞具有保护效应及其与微循环调节功能间的关系。方法:I/R与IPC组大鼠均复制脑I/R损伤模型,IPC组增加于I/R之前24h进行的短暂脑缺血预处理。动物均开颅窗观察缺血前、缺血后、再灌后脑软膜微循环指标;并取脑组织作红四氮唑(TTC)染色观察缺血损伤情况。结果:I/R组TTC染色后大多数出现不规则的缺血损伤的淡染区,而IPC组明显少见。IPC组缺血及再灌之后毛细血管累计总长度、微循环血流量、微血管内血流速度之相对增加值均大于I/R组。I/R组于再灌注之后有无复流现象;而IPC组此时呈灌注增加的过程。结论:IPC通过提高微循环的调节功能,促进毛细血管的相对性开放和血流的相对性加快,减轻缺血期组织血流低灌注和再灌注期无复流现象,从而对I/R脑产生一定保护作用。 相似文献
124.
骨形成蛋白-7对人肾小管上皮细胞株HK-2凋亡的影响 总被引:1,自引:0,他引:1
研究不同浓度的骨成形蛋白 7(BMP 7)对人近曲小管上皮细胞株HK 2凋亡的影响并初步探讨其可能的机制。应用Hoechst 332 5 8荧光染色、DNA电泳检测凋亡细胞的形态学和生化改变 ,流式细胞仪定量检测细胞的凋亡率 ,并观察凋亡特异性蛋白酶Caspase 3活性变化的情况。结果显示 ,HK 2细胞加入 1 0ng/mlTGF β处理 2 4h后 ,可明显抑制细胞生长并诱导细胞凋亡 ,呈现明显的凋亡形态学改变 ,胞核或核质内可见浓度致密的颗粒状荧光 ,DNA电泳呈现典型的“梯形条带” ,而预先加入 5 0ng/ml、 1 0 0ng/mlBMP 7共处理 2 4h后 ,可减轻TGF β对细胞的抑制作用 ,凋亡细胞亦减少 ,Caspase 3蛋白酶活性明显下降 ,细胞凋亡率下降。提示BMP 7对人肾小管上皮细胞凋亡的具有抑制作用 ,可能是通过抑制Caspase蛋白酶活性而实现的 相似文献
125.
目的 :观察人球结膜微血管的超微结构 ,认识白内障时球结膜微血管的电镜改变 ,为微循环和眼科研究工作提供参考。方法 :观察对象为 5例老年性白内障、1例糖尿病性白内障 ,术前一般状态良好。在白内障手术时取球结膜标本。电镜常规固定、包埋、定位、超薄切片、用电镜观察。结果 :球结膜毛细血管多由 2~ 3个内皮细胞围绕而成。核多为长椭圆形 ,核周缘有轻度凸凹。近腔侧胞浆细胞器较多 ,微丝和微管十分发达。基底膜、周细胞与一般毛细血管相似。 6例白内障球结膜毛细血管的内皮细胞、基底膜、周细胞、管腔都有不同程度的变化。其电镜改变可以分为三类 :( 1)代偿反应性增强改变 :微丝、微管十分发达、核周深凹、胞体突入管腔内、内皮细胞突起穿越基底膜、白细胞穿壁 ;( 2 )可恢复性退变 :线粒体退变、核质周集、胞浆出现空泡、基底膜分层、弥散、小量出血 ;( 3)严重不可恢复性改变 :核质固缩、腔内红细胞融合、血红蛋白溢出弥散、管壁断裂、腔内充满退变、裂解结构 ( 2例 ) ,并通过断裂处出至基底膜外。结论 :白内障病人球结膜微血管的超微结构有程度不等的改变 相似文献
126.
在目前不能直接观测病人内部器官微循环改变的条件下,应用模糊聚类的理论和方法,对主要常见病有意义的的甲襞微循环改变进行聚类,同时参考国内外相关文献的结果,提出了主要常见病有意义的甲襞微循环改变群。在改变群中任意提出3、4、5、6、7、8项改变指标,形成改变组合,一种组合重复出现二次以上的重复率,随组合改变指标数的增多而减少(70.36%~4.36%)。将改变群分成重要指标和参考指标二类,从每类中提出三项形成组合,重复率仅为0.34%。说明组合方式的影响十分巨大。经过反复探索、大量实践,有可能找出对疾病的符合率较高、漏诊率较低、误诊率较小的最佳组合方式。 相似文献
127.
Control of HIV-1 replication by RNA interference 总被引:15,自引:0,他引:15
128.
Reduced expression of tissue inhibitor of metalloproteinase (TIMP)-2 in gestational trophoblastic diseases 总被引:14,自引:0,他引:14
To elucidate the involvement of type IV collagenases [matrix metalloproteinase (MMP)-2 and MMP-9] and their tissue inhibitors (TIMP-1 and TIMP-2) in the development of gestational trophoblastic disease (GTD), we quantified their levels in hydatidiform mole and choriocarcinoma tissues using specific enzyme-linked immunosorbent assays, and the results were compared with those from normal first trimester placenta. Levels of pro-MMP-2 were increased in hydatidiform mole, and they were further elevated in choriocarcinoma. Levels of pro-MMP-9 in choriocarcinoma and those of TIMP-1 in both hydatidiform mole and choriocarcinoma were also increased. In contrast, TIMP-2 levels were markedly decreased in both hydatidiform mole and choriocarcinoma. Similar results were obtained by the tissue culture of first trimester placenta and hydatidiform mole. Gelatin zymography indicated that the levels of both pro- and activated forms of MMP-2 and MMP-9 were higher in hydatidiform mole and choriocarcinoma. The decreased expression of TIMP-2 in hydatidiform mole and choriocarcinoma was confirmed by Western blot, Northern blot and immunohistochemistry, with the decrease being more pronounced in choriocarcinoma. Taken together, the present study shows that both TIMP-2 mRNA and protein levels are markedly decreased in GTD and the imbalance of MMP-TIMP production, shifted toward greater MMP activity, may be involved in the pathogenesis of GTD. 相似文献
129.
Richard Meehan Ulric Duncan Laureen Neale Gerald Taylor Harold Muchmore Nan Scott Keith Ramsey Eric Smith Paul Rock Randall Goldblum Charles Houston 《Journal of clinical immunology》1988,8(5):397-406
We investigated the effects on immune function after progressive hypobaric hypoxia simulating an ascent to 25,000 ft (7620 m) over 4 weeks. Multiple simultaneousin vitro andin vivo immunologic variables were obtained from subjects at sea level, 7500 ft (2286 m), and 25,000 ft during a decompression chamber exposure. Phytohemag-glutinin-stimulated thymidine uptake and protein synthesis in mononuclear cells were reduced at extreme altitudes. Mononuclear-cell subset analysis by flow cytometry disclosed an increase in monocytes without changes in B cells or T-cell subsets. Plasma IgM and IgA but not IgG levels were increased at altitudes, whereas pokeweed mitogen-stimulatedin vitro IgG, IgA, and IgM secretion was unchanged. During exposure to 25,000 ft,in vitro phytohemagglutinin-stimulated interferon production and natural killer-cell cytotoxicity did not change statistically, but larger intersubject differences occurred. IgA and lysozyme levels (nasal wash) and serum antibodies to nuclear antigens were not influenced by altitude exposure. These results suggest that T-cell activation is blunted during exposure to severe hypoxemia, whereas B-cell function and mucosal immunity are not. Although the mechanism of alteredin vitro immune responsiveness after exposure to various environmental stressors has not been elucidated in humans, hypoxia may induce alterations in immune regulation as suggested byin vitro immune assays of effector-cell function.Some of this study's results were presented as an abstract at the FASEB meeting in St. Louis, Missouri, 1986. 相似文献
130.