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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:探讨尿激酶型纤溶酶原激活物(uPA)及其受体(uPAR)和抑制剂(PAI-1)血浆含量与卵巢恶性肿瘤之间的关系。方法:收集52例卵巢恶性肿瘤患者血液标本,以30例健康人作对照,用ELISA法分别检测uPA、uPAR和PAI-1的含量。结果:uPA、uPAR在卵巢恶性肿瘤各期之间均有极显著性差异(P〈0.01),PAI-1在卵巢恶性肿瘤FIGO Ⅰ~Ⅲ期的含量逐渐升高,但在FIG0Ⅳ期时显著下降(P〈0.05)。患者组uPA、uPAR、PAI-1均较对照组升高,差异极显著(P〈0.01)。结论uPA、uPAR在卵巢恶性肿瘤患者可作为预后的判断指标,PAI-1与卵巢恶性肿瘤的分期有一定的相关性。  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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卢海  张风 《国际眼科杂志》2007,7(3):692-694
目的:探讨增殖性糖尿病视网膜病变(PDR)中组织纤溶酶原激活物(t-PA)及纤溶酶原激活物抑制剂(PAI)的表达以及与血管内皮生长因子(VEGF)表达的相关性.方法:于玻璃体手术中采集PDR 35眼玻璃体,同时采集因黄斑裂孔行玻璃体手术20眼玻璃体作为对照组,采用酶联免疫吸附法检测t-PA及PAI的表达浓度,并与VEGF的表达进行相关性分析.结果:PDR眼玻璃体中VEGF、t-PA及PAI的表达浓度均显著高于对照眼玻璃体(P<0.001).t-PA及PAI的表达与VEGF的表达经统计学分析,均存在显著相关性(P<0.001).结论:在PDR眼内视网膜新生血管的发生过程中不仅有VEGF,可能同时有多种生物活性物质的参与.  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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Diet is important in the prevention of cardiovascular disease, and it has been suggested that a high-MUFA diet is more cardioprotective than a low-fat diet. We hypothesised that the postprandial thrombotic risk profile is improved most favourably by a high-MUFA diet compared with a low-fat diet. This was tested in a parallel intervention trial on overweight individuals (aged 28.4 (SD 4.7) years) randomly assigned to a MUFA-diet (35-45% of energy as fat; > 20% as MUFA, n = 21) or a low-fat (LF) diet (20-30% of energy as fat, n = 22) for 6 months after a weight loss of ~ 10%. All foods were provided free of charge from a purpose-built supermarket. Meal tests designed after the same principles were performed before and after the dietary intervention, and blood samples were collected at 8.00 h (fasting), 12.00 h, and 18.00 h and analysed for factor VII coagulant activity (FVII:C), activated FVII, fibrinogen, prothrombin fragment 1 + 2 (F1 + 2), D-dimer, plasminogen activator inhibitor (PAI:Ag), and thrombin activatable fibrinolysis inhibitor. There were significant postprandial increases in F1 + 2 and D-dimer before and after dietary intervention, with significantly lower values after 6 months. No significant differences were observed between the postprandial changes induced by the two diets. The postprandial decrease in FVII:C and PAI:Ag did not differ before and after intervention, irrespective of the diets. Our findings suggest postprandial coagulation activation in overweight subjects with more pronounced acute than long-term effects. We observed similar effects of the MUFA diet and the LF diet on the postprandial prothrombotic risk profile.  相似文献   
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