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排序方式: 共有333条查询结果,搜索用时 15 毫秒
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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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目的:探索血清D-二聚体(D-dimer,D-D)、纤维蛋白原(fibrinogen,FIB)、血小板(platelet,PLT)、C反应蛋白(C-reactive protein,CRP)联合组织型纤溶酶原激活物抑制剂-1(plasminogen activator inhibitor-1,PAI-1)水平预测老年髋关节术后下肢深静脉血栓(deep vein thrombosis,DVT)的价值。方法:回顾性分析2020年2月至2022年5月收治的165例老年髋关节术患者,男89例,女76例;年龄60~75(66.43±5.48)岁;股骨颈骨折102例,股骨头坏死63例。所有患者入院24 h内均进行血清D-D、FIB、PLT、CRP、PAI-1检测,根据患者是否发生DVT分为DVT组和非DVT组。结果:DVT组患者的D-D、FIB、PLT、CRP、PAI-1水平均高于非DVT组(P<0.001);Spearman分析结果显示,DVT与PLT、CRP、D-D、FIB、PAI-1水平均呈正相关性(r=0.382,0.213,0.410,0.310,0.353,均P<0.001);二分类Logistic回归分析结果显示,D-D、PLT是影响DVT发生的独立因素(OR=0.038,0.960,P=0.032,0.011);D-D、FIB、PLT、CRP、PAI-1及五项联合预测DVT的曲线下面积(area under curve,AUC)分别为0.843、0.692、0.871、0.780、0.819、0.960,五项联合预测的AUC均高于单项预测(P<0.05)。结论:D-D、FIB、PLT、CRP、PAI-1在预测老年髋关节术后发生DVT中具有一定效能,五项联合预测效能更高。  相似文献   
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Effects of rhein on human articular chondrocytes in alginate beads   总被引:6,自引:0,他引:6  
This study was designed to investigate the effects of rhein, the active metabolite of diacerhein, on the metabolic functions of human chondrocytes cultured in alginate beads.Enzymatically isolated osteoarthritic (OA) chondrocytes were cultured in alginate beads in a well-defined culture medium for 12 days. Rhein was tested in a range of concentrations comprised between 10(-7) and 4 x 10(-5)M, in the presence or absence of 10(-10)M IL-1beta. Interleukin (IL)-6 and -8, macrophage inflammatory protein (MIP-1beta), stromelysin-1 (MMP-3), aggrecan (AGG), tissue inhibitor of metalloproteinases-1 (TIMP-1), prostaglandin E(2) (PGE(2)) and nitric oxide (NO) productions were assayed. Cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) mRNA steady-state levels were also quantified. In the basal condition, 10(-5)M rhein increased by 46.5% the production of AGG, decreased by 17-30% the production of IL-6, MMP-3, NO and MIP-1beta but enhanced by 50% the production of PGE(2). IL-1beta increased IL-6, IL-8, MIP-1beta, NO, PGE(2) and MMP-3 productions, but inhibited AGG and TIMP-1 synthesis. Rhein partially reversed the effect of IL-1beta on TIMP-1 and NO production, had no effect on AGG, IL-6 and MIP-1beta production, but up-regulated the IL-1beta stimulated PGE(2) production. The COX-2 and iNOS mRNA levels and IL-8 production were not modified by rhein.Overall, these results contribute to explain the clinical efficiency of rhein and give new information on its mechanisms of action.  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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