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51.
肌钙蛋白T在诊断急性心肌梗死中的应用   总被引:2,自引:0,他引:2  
采用肌钙蛋白T半定量试纸条检测急性心肌梗死16例,心绞痛13例,以20例健康体检者为对照组。结果显示,AMI组阳性反应15例,心绞组仅1例阳性,对照组均为阴性,结果提示,TnT半定量试纸条检测法在AMI诊断中,敏感性和特异性较高,方法简便方便,尤其适用于急诊室,内科监护病房及基层医院使用。  相似文献   
52.
Flow-independent angiography (FIA), an approach that isolates arterial blood using MR relaxation characteristics rather than flow effects, was evaluated for application in peripheral vascular disease (PVD). First, pilot studies were conducted in which FIA coronal projection images were obtained from controls and symptomatic patients with PVD to assess clinical utility. All control images corresponded to the expected leg arterial anatomy with little interference from deep veins (one of five) and muscle (zero of five). Superficial venous signal was less well suppressed in comparison to deep veins (four of five). Images of symptomatic patients were less consistent with difficulty suppressing muscle and deep venous signal in some cases and edema when present. We then compared T2 values for muscle (T2m, tibialis anterior), arterial blood (femoral and popliteal arteries), and venous blood (femoral, popliteal, and saphenous veins) in controls (n = 8) and symptomatic patients with intermittent claudication (n = 5) or ischemic rest pain (n = 7). Changes in T2 measurements of various tissues accounted for poorer contrast in symptomatic patients. Patients with ischemic rest pain had significantly higher T2m compared with controls (T2m = 39.3 ± 2.1 (1 standard error of the mean [SEM]) versus 30.9 ± .4, P < .01). For all measurements, other than saphenous vein, variances were greater in symptomatic patients. To realize the inherent advantages of FIA for this clinical application, additional work on suppression of signals from muscle, veins, and edema is required. One promising approach involves shifting from projection images to three-dimensional acquisitions for improved tissue suppression.  相似文献   
53.
本文应用磁性磷酸酶-抗碱性磷酸酶桥联酶标技术(APAAP),对27例原发性肾小球疾病患者外周血T淋巴细胞亚群进行观察。结果表明:本组病例表现为CD细胞升高,CD细胞减少,和CD/CD比值增加。提示原发性肾小球疾病可导致细胞免疫功能改变,T淋巴细胞亚群的变化,是肾组织损害的一个间接证据,可作为临床诊断一个有价值的参考指标。  相似文献   
54.
We investigated populations of the infiltrating cells in Bowen's disease (BD) and squamous cell carcinoma (SCC), both of which arose in the same patient, using the Avidin-Biotin-peroxidase complex method with eight monoclonal antibodies. T lymphocytes were most predominant among infiltrating cells; NK cells, B cells, and monocytes were rarely seen in either BD or SCC. Analysis of subsets of the infiltrating T lymphocytes revealed that the number of suppressor/cytotoxic (s/c) T cells was twice that of helper/inducer (h/i) T cells in BD, while the number of s/c T cells was lower than that of h/i T cells in SCC. The immunohistochemical results in the present case differed from those of predominant infiltration of h/i T cells and of s/c T cells in three other reports of BD and SCC. These results suggest that the population of the cellular infiltrates may be modulated by the nature of tumors and by the immuno-competent state of the hosts.  相似文献   
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A panel of synthetic peptides representing human lymphocyte antigen (HLA) B8, other class I and class II restricted T cell epitopes and two B cell epitopes, were all able to compete with recognition of a HLA B8 restricted epitope by a cytotoxic T cell clone. Competition was obtained when the competitor peptides were added either before or after the target epitope. The target epitope also had a slow off rate, implicating allosteric inhibition. The presence of non-specific, allosteric binding sites may interfere with experiments attempting to define immunologically relevant MHC binding specificities.  相似文献   
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精神分裂症服用氯氮平能降低其甲状腺素水平的对照分析   总被引:2,自引:0,他引:2  
目的探索氯氮平治疗是否影响T3、T4和TSH水平.方法对17例精神分裂症患者,给予氯氮平治疗第4天和第4周末分别测定T3、T4和TSH水平.结果治疗第4周末的T3(3.309±0.689)、T4(9.449±1.941)水平比第4天的T3(3.915±0.850)、T4(11.178±2.180)水平明显降低(P均<0.05).结论氯氮平治疗能降低甲状腺素水平.  相似文献   
60.
Syphilis is a chronic disease characterized by hematogenous dissemination of Treponema pallidum into tissues such as the cardiovascular and central nervous systems. In order to test whether these aspects of the pathogenesis of syphilis reflect an ability of T. pallidum to invade vascular entothelial surfaces, we explored the association of T. pallidum with human and rabbit endothelial cells in vitro. Using radiolabeled motile organisms, we found that treponemal attachment was two times greater to rabbit aortic endothelial cells and human umbilical endothelial cells than to HeLa cells. Mild trypsinization of attached treponemes resulted in release from cells of all organisms detectable by darkfield microscopy without visible damage to the monolayer. Nevertheless, 25% of the counts representing T. pallidum remained associated with the cell monolayers. Further trypsin treatment to release the monolayer and differential centrifugation showed that 80% of the remaining cell-associated counts were not within the cells. These results suggest that some treponemes had associated with the monolayer in a trypsin resistant niche. Additionally, motile T. pallidum passed through tight functioned endothelial cell monolayers on membrane filters under conditions were heat-killed T. pallidum and the host indigenous nonpathogen. T. phagedenis biotype Reiter failed to do so. Electron micrographs of transverse sections through the monolayers showed many T. pallidum in junctions between endothelial cells. These studies suggest that T. pallidum may leave the circulation by passing between endothelial cells.  相似文献   
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