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91.
目的研究肺癌患者血栓前状态(prethmmbotic state PTS)分子标志物变化并探讨其意义。方法采用酶联免疫吸附双抗体夹心法检测82例肺癌患者和50名正常人凝血、抗凝纤溶系统实验室指标,包括血小板α颗粒膜蛋白-140(GMP-140)、凝血酶原片段1+2(F1+2),凝血酶-抗凝血酶复合物(TAT),D-二聚体(D-dimer)。结果肺癌患者体内GMP-140、F1+2、TAT、D-dimer的水平较正常人显著升高(P0.05),上述指标在晚期肺癌组和PS评分2的患者中明显升高(P0.05)。结论肺癌患者出现血小板活化、凝血功能增强、纤溶功能减退,存在明显的血栓前状态。  相似文献   
92.
One of the main challenges in targeted alpha therapy is assuring delivery of the α-particle dose to the targeted cells. Thus, it is critical to identify ligands for α-emitting radiometals that will form complexes that are very stable, both in vitro and in vivo. In this investigation, thorium-227 (t1/2 = 18.70 days) chelation of ligands containing hydroxypyridinonate (HOPO) or picolinic acid (pa) moieties and the stability of the resultant complexes were studied. Chelation reactions were followed by reversed-phased HPLC and gamma spectroscopy. Studies revealed that high 227Th chelation yields could be obtained within 2.5 h or less with ligands containing four Me-3,2-HOPO moieties, 1 (83%) and 2 (65%), and also with ligands containing pa moieties, H4octapa 3 (65%) and H4py4pa 6 (87%). No reaction occurred with H4neunpa-p-Bn-NO2 4 , and the chelation reaction with another pa ligand H4pypa 5 gave inconsistent yields with a very broad radio-HPLC peak. The ligands spermine-(Me-3,2-HOPO)4 1 , H4octapa 3 , and H4py4pa 6 had high stability (i.e., 87% of 227Th still bound to the ligand) in phosphate-buffered saline at room temperature over a 6-day period. Preliminary studies with ligand 6 demonstrated efficient chelation of thorium-226 (t1/2 = 30.57 min) when heated to 80°C for 5 min.  相似文献   
93.
空针死腔对TAT皮试结果影响的临床观察   总被引:15,自引:0,他引:15  
破伤风抗毒素 (TAT)过敏试验 ,按传统判断标准[1] ,阳性率甚高 ,文献报道为 76.1%~ 99% [2~ 4] ,其中假阳性为 61.7%~ 75 .8% ,为降低其假阳性率 ,护理同行们主张合理设计皮试结果的判断标准。而近年来 ,我们通过临床观察 ,发现lml空针 (本文所指者均为一次性 )针头处死腔容积约为 0 .1ml,若用之按传统方法配制TAT皮试液 ,则配制出的皮试液浓度将受到较大的影响。为探讨空针死腔对TAT皮试液浓度进而对皮试结果假阳性是否也造成影响 ,因而对原配制方法进行改良 ,并将两种方法所配的TAT皮试液对 14 36例需注射TAT的病…  相似文献   
94.
TAT融合蛋白在SD大鼠肾组织表达的研究   总被引:1,自引:0,他引:1  
目的 :探讨分子量为 12 0kD的TAT融合蛋白在SD大鼠肾组织的吸收及酶活性的表达情况。方法 :利用“蛋白转导”的方法 ,将人类免疫缺陷病病毒HIV的TAT蛋白与 β -半乳糖苷酶 (β -Galactosidase,β -Gal)相连接 ,构建形成TAT - β -Gal融合蛋白 (分子量为 12 0kD)。将 72只SD大鼠随机分为 3组 (每组n =2 4 ) ,分别腹腔注射TAT - β -Gal、β -Gal和生理盐水 ,于注射后不同时间段取肾组织作病理切片 ,用X -Gal染色分析 ,显微镜下观察肾脏对TAT - β -Gal的吸收及酶活性的表达情况 ,并进行Leica计算机图像分析 ,同时观察肾组织结构改变。结果 :TAT - β -Gal组在经腹腔注射TAT - β -Gal 0 .5h后切片 ,用X -Gal染色 ,显微镜下即可显示着色反应 ,TAT - β -Gal可以快速到达肾组织 ,在肾小球细胞表达酶的活性 ,于 8h达到高峰 ,16h逐渐下降 ;β -Gal组经X -Gal染色后出现极弱的着色反应 ;而生理盐水组 ,经X -Gal染色后无着色反应。结论 :分子量为 12 0kD的TAT -β-Gal融合蛋白可以迅速被SD大鼠肾组织所吸收 ,同时不影响所连接蛋白酶的活性。HIV的TAT蛋白可以作为载体转运大分子 (蛋白或肽类大分子 )物质通过生物膜进入细胞内 ,为临床应用大分子物质治疗疾病提供实验依据  相似文献   
95.
The flow cytometric crossmatch (FCXM) assay, which detects the presence of donor specific HLA antibodies in patient sera, is a cornerstone of HLA compatibility testing. Since relatively long FCXM assay turnaround times may contribute to transplant delays and increased graft ischemia time, we developed and validated two modified crossmatch procedures, namely the Halifax and Halifaster FCXM protocols. These protocols reduce FCXM assay time?>60% and simplify their set-up without compromising quality or sensitivity. Optimization of the FCXM (the Halifax protocol) includes a 96-well tray platform, reduced wash times, increased serum to cell suspension volume ratio, shortened incubations and higher incubation temperature. The Halifaster protocol is a further modification, employing methods that improve lymphocyte purity compared to density gradient centrifugation (96?±?2.63% vs 69?±?19.06%), reduce cell isolation time (by?~40%) and conserve FCXM assay reagents. Importantly, linear regression analysis of the median channel fluorescence shift (MCFS) values revealed excellent concordance (R2 of 0.98–0.99) among all three FCXM protocols (standard vs Halifax vs Halifaster). Finally, a retrospective review of 2013 crossmatches performed using the Halifax protocol demonstrated excellent correlation with the virtual crossmatch (95.7% and 96.8% specificity and sensitivity, respectively) regarding the identification of donor specific antibodies (HLA-A/B/DR) assigned based on the single antigen bead (SAB) assay testing with a 2000 mean fluorescence intensity (MFI) cutoff. Implementation of the Halifax or Halifaster protocols will expedite pre-transplantation work-up and improve patient care.  相似文献   
96.
Despite the improvements in the development of dialyzer membranes with greater hemocompatibility, an activation of the coagulation system occurs when blood comes into contact with exogenous surfaces. The large number of heparin dosage regimens demonstrate the difficulty to adapt general therapeutic guidelines. Low molecular weight heparin (Fragmin®) was administered as a single bolus dose for anticoagulation during 58 acute dialyses. Anti-Xa-activity, the plasma levels of the lysosomal elastase of the polymorphnuclear granulocytes (PMN-elastase) and of the thrombin-antithrombin III-complex (TAT) were measured at hourly intervals. Therapeutic anti-Xa-levels did not show evidence of sufficient inhibition of thrombin formation. The PMN-elastase increased by 180 ng/ml 3 h after administration of the bolus dose, with no further increase occurring (plateau phase). This was considered to reflect adequate anticoagulative activity. Where anticoagulation was inadequate, the elastase values rose consistently. After 2 h the increase of the PMN-elastase showed that — and to what extent — coagulation had been activated. The determination of PMN-elastase, using the IMAC-principle, is a method which can be performed quickly with any conventional autoanalyzer. It makes it possible to monitor adequate anticoagulation, but PMN-elastase results must be proven during routine use before recommendation as a routine test.  相似文献   
97.
目的:了解我室急诊生化的样本周转时间(turn-around time,TAT)现状,分析造成TAT延迟的原因,找到合理的解决方案.方法:利用实验室信息系统收集2008年1月至8月急诊生化的TAT数据,按月份(1~8月)、工作日(星期一至星期日)、每日时间段(抽取8月TAT数据)进行整理,对比分析TAT平均值及不符合率.结果:从月份来看,4、5、8月样本量较多,TAT平均值较大,不符合率较高;从工作日来看,星期一、二样本量较多,TAT平均值较大,不符合率较高;从每日时间段来看,8:00-12:00以及16:00-18:00时间段TAT平均值较大,不符合率较高.结论:样本量与TAT平均值和不符合率之间大致呈正相关关系;TAT延长的原因包括样本量较大尤其是样本高峰期造成的检测拥堵,大项目组合多,仪器的维护质控等;解决的对策包括添置急诊分析设备,加强检验与临床的联系,加强人员培训,优化工作流程等.  相似文献   
98.
The structural flexibility of antithrombin is essential for its molecular trapping mechanism but also makes it vulnerable to even minor changes affecting its conformational stability, which influences hemostasis significantly. The conformational transformation of this serpin has been poorly investigated in biologic samples because available immunologic methods hardly differentiate between different conformations of this protein. Crossed immunoelectrophoresis (CIE) in presence of heparin has been classically used to identify mutant antithrombins with low heparin affinity. We demonstrate that this method also separates native and relaxed antithrombin, permitting the analysis of conformational variations of this potent anticoagulant with just a few microliters of plasma. However, CIE does not distinguish between antithrombin conformations with reduced heparin affinity: latent, cleaved, thrombin-antithrombin complexes, or heparin-binding mutants. Therefore, clinical interpretation of CIE results should be examined with caution. Using this and other methods, and evaluating the functional activity of antithrombin, we analyzed the conformational transformation of antithrombin in biologic samples. We confirmed its transformation to the latent configuration by incubating it at 50 degrees C. This conformational change also occurs at 37 degrees C, supporting the idea that this process is involved in the senescence of antithrombin. However, fresh plasma contains only traces of latent antithrombin, suggesting that this conformation is rapidly cleared in vivo. Finally, small increases in temperature (to 40 degrees C) resulted in a faster conformational transformation of antithrombin. Fever has been suggested to have key structural, functional, and clinical consequences in patients with conformational mutations in antithrombin. Our results support a role for small changes in temperature in nonmutated antithrombin, suggesting that fever is a general risk factor for thrombosis.  相似文献   
99.
目的探讨品管圈活动降低注射破伤风抗毒素(tetanus antitoxin,TAT)皮试阳性率的效果。方法2015年6月,山西医科大学第二医院急诊科开展了以"降低TAT皮试阳性率"为主题的品管圈活动。按照品管圈实施的十大步骤调查、分析破伤风皮试的各个环节、分析影响破伤风皮试结果的各种因素。便利抽样法选取2015年4-5月在该院行TAT皮试的382例患者为实施前组,同法选择2015年6-7月在该院行TAT皮试的391例患者为实施后组。比较两组患者的TAT皮试的阳性率、TAT注射用时、患者对护理工作的满意度以及实施前后护理人员的理论及操作水平。结果通过品管圈活动,规范了TAT皮试的操作流程。TAT皮试的阳性率由86.3%降低到38.1%,患者对护理工作的满意度由95.6%提升到98.1%,护理人员的理论及操作水平均有明显提升(均P0.05)。结论品管圈活动在护理工作中开展是行之有效的,能提高患者对护理工作满意度,同时提升护理团队的理论及操作水平,是改进护理质量的有效方式。  相似文献   
100.

Introduction

Hypercoagulation was suggested to be involved in preterm birth etiology; however, the coagulation state of preterm parturients remains unelucidated. The study aim was to evaluate the haemostatic system of pregnant women with premature uterine contractions (PUC).

Materials and Methods

The cohort study population consisted of 76 healthy pregnant women admitted with regular PUC. The study group included 38 women who experienced preterm birth; 14 of them had preterm premature rupture of membranes (PPROM). The control group included 38 women who eventually had term delivery. Groups were matched for maternal age, number of births and gestational age at admission. Blood samples were tested for haemostatic parameters and coagulation activation markers.

Results

Significantly shorter PT and aPTT were documented in the study compared to control group (25.7 ± 2 vs. 27.4 ± 2.7 seconds, P = 0.003, and 9.96 ± 0.5 vs. 10.1 ± 0.4 seconds, P = 0.05, respectively), although differences in absolute values were small. There was no significant difference between the two groups in levels of: fibrinogen, D-dimer, protein C-global, free protein S antigen, factor VIII activity, Von Willebrand factor, plasminogen activator inhibitor-1, prothrombin fragments F1 + 2 (PT F1 + 2), tissue factor and tissue factor pathway inhibitor.Women with PPROM had significantly lower PT F1 + 2 levels compared to those who had preterm delivery with intact membranes (351 ± 99 vs. 561 ± 242 pmol/L, P = 0.003).

Conclusions

Shortened PT and aPTT, reflecting increased thrombotic activity in maternal plasma, could serve as a marker of real preterm labor in women with premature uterine contractions. Further prospective studies in a larger cohort are warranted to validate these findings.  相似文献   
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