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1.
目的研究我国汉族人纤溶酶原激活物抑制物-1基因启动子区-675位4G/5G(单鸟嘌呤核苷酸插入/缺失)基因多态性与心肌梗死和脑梗死的等位基因特异性的相关性.方法以等位基因特异性聚合酶链反应(AS-PCR)扩增56例心肌梗死患者,54例脑梗死患者,83例无关健康对照个体的基因组DNA,鉴定PAl-1 4G/5G基因型及分布频率,常规方法检验研究个体的主要临床和生化指标.结果PAI-1基因启动子区4G/5G基因多态性在心肌梗死,脑梗死患者组中的分布频率与对照组明显不同.在心肌梗死组中,4G/4G基因型分布频率(71.40%)比对照组(30.12%)显著增加(P<0.001),杂合型4G/5G基因型分布频率(25.00%)比对照组(62.65%)明显降低;而在脑梗死组中,4G/4G,4G/5G基因型分布频率(分别为20.37%,55.56%)均比对照组(分别为30.12%,62.65%)低,5G/5G基因型明显增加(24.07%vs7.32%,P<0.001).而且心梗组中血浆PAI-1活性水平随着4G等位基因的减少而降低;脑梗死组中,血浆PAI-1活性水平随着5G等位基因的升高而增加.心肌梗死、脑梗死患者组中的血浆PAI-1活性水平,甘油三酯水平和血糖水平都比对照组明显升高(分别为P<0.001,P<0.05,P<0.001).结论本研究表明,中国汉族人PAI-1基因启动子区4G/5G基因多态性可能和心肌梗死、脑梗死发生的危险性相关,4G/5G基因多态性可能是一种重要的遗传性血栓性疾病的危险因子.  相似文献   
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Ⅱ型糖尿病血浆PAI-1、t-PA检测的意义和结果评价   总被引:1,自引:1,他引:0  
目的:通过对Ⅱ型糖尿病患者分组(伴血管病变组、胰岛素抵抗组、胰岛素抵抗伴血管病变组、Ⅱ型糖尿病组)检测PAI-1、t-PA抗原及活性,并计算抗原比和活性比,以评价各检测指标的临床价值。方法:采用ELISA法检测PAI-1及t-PA抗原,采用发色底物法检测PAl-1、t-PA活性。结果:189例标本总体患病组及分组后各组的PAI-1活性、t-PA活性及t-PA活性/PAI-1活性比值与正常对照组比较均有显著性差异(P<0.05)。患病组间除t-PA抗原,其余检测显示胰岛素抵抗组、胰岛素抵抗组伴血管病变组与Ⅱ型糖尿病组存在显著性差异(P<0.05)。结论:在上述检测指标中t-PA活性、PAI-1活性反映血管病变的发生较敏感,t PA/PAI-1的活性比值更具临床应用价值。  相似文献   
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OBJECTIVE: To clarify the role played by tissue factor pathway inhibitor (TFPI) in pregnancy hypertension. METHODS: Using enzyme-linked immunosorbent assays, hemostatic measurements were obtained for women with pre-eclampsia (n=51), nonproteinuric hypertension of pregnancy (n=62), postpartum pre-eclampsia 24 h after childbirth (n=31), and no hypertension (healthy pregnant controls, n=100). RESULTS: There was a significant increase in circulating free TFPI levels in women with pre-eclampsia (9.7+/-6.2 ng/mL) or nonproteinuric hypertension of pregnancy (8.3+/-5.3 ng/mL) compared with healthy controls (5.3+/-2.1 ng/mL). In women with pre-eclampsia the levels remained elevated after placental delivery (10.6+/-4.0 ng/mL). Free protein S levels were significantly higher in women with pre-eclampsia (40.0%+/-10.7%), nonproteinuric hypertension of pregnancy (37.1%+/-12.5%), or postpartum pre-eclampsia (39.3%+/-9.1%) than in healthy pregnant controls (32.2%+/-8.5%). CONCLUSION: Increased levels of the physiologically active free forms of TFPI and free protein S, 2 coagulation inhibitors, may protect women with pregnancy-induced hypertension from the risks of hemostatic activation.  相似文献   
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BACKGROUND: Side effects of platelet transfusion may be associated with infusion of bioactive substances. We therefore studied extracellular accumulation of histamine, plasminogen activator inhibitor (PAI)-1, vascular endothelial growth factor (VEGF), and interleukin (IL)-6 during preparation and storage of various platelet concentrates. METHODS: Twenty buffy-coat-derived platelet pools (BCPC) were prepared and stored in platelet additive solutions (PAS). Twelve apheresis platelet (APC) units were prepared using the COBE Spectra LRS, and 14 were prepared using the Fenwal Amicus Separator. After preparation half of the content was drawn from each APC unit. The normal ranges of the substances were determined in plasma from all donors, and the extracellular concentrations of the substances were determined in supernatants collected on days 0, 1, 3, 5, and 7 of storage from all platelet preparations. RESULTS: The platelet counts were not significantly different in BCPC units and APC units. The BCPC units had a significantly higher white cell count than the APC units (P < 0.0001), but the count was significantly higher in the Amicus APC units than in the COBE APC units (P < 0.0001). The extracellular histamine concentration was significantly (P < 0.001) increased in BCPC units after preparation and without further increase during storage, while there was no accumulation of histamine in APC units. After preparation the PAI-1 concentration was significantly (P < 0.02) higher in BCPC units than in APC units, but during storage PAI-1 increased significantly (P < 0.05) more in APC units than in BCPC units. Similarly, VEGF concentration was significantly (P < 0.05) higher in BCPC units than in APC units after preparation. During storage, however, VEGF increased more in BCPC units compared with COBE Spectra APC units (P < 0.05), but compared with Amicus Separator APC units only for the first 3 days of storage. At days 5 and 7 of storage the VEGF concentration was significantly higher in the Amicus APC units than in the COBE APC units (P < 0.05). IL-6 was not detectable in any of the concentrates after preparation or during storage. CONCLUSION: Platelet concentrates prepared by the apheresis method may contain less white cell derived bioactive substances than platelet concentrates prepared by the buffy-coat method. However, a substantial storage time dependent platelet derived bioactive substance accumulation takes place in all platelet concentrates tested, presumably due to platelet disintegration.  相似文献   
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Streptococcus suis (S. suis) serotype 2 usually cause infection in swine. Recently, two large-scale outbreaks in China with severe streptococcal toxic shock syndrome (STSS) and high mortality raised worldwide concern to human S. suis infection. To reveal the molecular pathogenesis of S. suis 2 during human infection, in-vivo induced antigen technology (IVIAT) was applied to identify the in-vivo induced genes (ivi genes) of S. suis 05ZYH33. The ivi genes are specifically expressed or up-regulated in-vivo and always associated with the in-vivo survival and pathogenicity of pathogens. In present study, convalescent sera from S. suis 05ZYH33 infected patients were pooled and fully adsorbed with in-vitro grown S. suis 05ZYH33 and Escherichia coli BL21 (DE3). Genomic expression library of 05ZYH33 was repeatedly screened with colony immunoblot assay using adsorbed sera. Finally, 19 genes were assessed as ivi genes of 05ZYH33. Fifteen of 19 genes encode proteins with biological functions in substance transport and metabolism, cell structure biogenesis, cell cycle control, replication, translation and other functions. The 4 remaining genes encode proteins with unknown functions. Of the 19 ivi genes, five (SSU05_0247, 0437, 1577, 1664 and 2144) encode proteins with no immunoreactivity to control sera from healthy individuals never exposed to 05ZYH33. The successful identification of ivi genes not only sheds light on understanding the pathogenesis of S. suis 05ZYH33 during its human infection, but also provides potential targets for the developments of new vaccines, therapeutic drugs and diagnostic reagents against human S. suis infection.  相似文献   
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目的探讨复发性流产伴胰岛素抵抗患者的中医体质分布特征,了解此类患者血清SHBG、PAI-1水平,并探讨其与中医体质的关联性。方法采用横断面问卷调查形式,选择复发性流产伴胰岛素抵抗患者92例(观察组)和复发性流产不伴胰岛素抵抗患者92例(对照组),比较两组中医体质及血清SHBG及PAI-1水平进行统计分析。结果观察组中医体质类型以阳虚质(27.01%)、气郁质(13.79%)、痰湿质(12.07%)为主,对照组以阳虚质(34.67%)、气郁质(13.33%)、阴虚质(11.33%)为主,两组痰湿质差异有统计学意义(P<0.05)。观察组中血清SHBG的表达水平为(9.692.78)nmol/ml,对照组中血清SHBG的表达水平为(11.09±2.56)nmol/ml,观察组中血清SHBG表达水平低于对照组,差异具有统计学意义(P<0.05)。观察组中血清PAI-1的表达水平为(11,056.1±1631.8)pg/ml,对照组中血清PAI-1的表达水平为(10,302.7±1688.8)pg/ml,观察组中血清PAI-1的表达高于对照组,差异有统计学意义(P<0.05)。复发性流产伴胰岛素抵抗患者不同的中医体质类型中阳虚质的SHBG表达水平为(9.51±3.14)nmol/ml,气郁质SHBG表达水平为(9.96±2.94)nmol/ml,痰湿质SHBG表达水平为(9.94±2.50)nmol/ml,各组间比较差异无统计学意义(P>0.05)。阳虚质的PAI-1表达水平为(11,241.6±1701.7)pg/ml,气郁质PAI-1表达水平为(10,739.3±1334.6)pg/ml,痰湿质PAI-1表达水平为(11,046.7±1372.1)pg/ml,各组间比较差异无统计学意义(P>0.05)。结论复发性流产伴胰岛素抵抗患者中医体质以阳虚质、气郁质、痰湿质为主。血清SHBG水平在复发,性流产伴胰岛素抵抗患者表达偏低,血清PAI-1水平在复发性流产伴胰岛素抵抗患者表达升高。  相似文献   
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