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551.
Sera from three unrelated persons whose red cells (RBC) had the common Scianna phenotype (Sc:1,-2) contained IgG alloantibodies directed against high-frequency RBC antigens. In each case, sera or eluates or both failed to react only with Scianna null (Sc:-1,-2) cells, although an eluate from one person was compatible with a sibling's Sc:1,-2 cells. Cross-testing cells with sera or eluates, or both, from the three persons revealed no mutual compatibility. These studies show the existence of three additional RBC antigens phenotypically related to the Scianna blood group system. Sc:-1,-2 cells lack these antigens, which indicates that Scianna null cells lack multiple high-frequency antigens.  相似文献   
552.
Column agglutination technology: the antiglobulin test   总被引:1,自引:0,他引:1  
A new system for typing and screening blood, based on the sieving effect of glass bead microparticles, has been developed. The test is performed in a microcolumn in which the red cell agglutinates are trapped in the glass bead matrix during centrifugation, and unagglutinated cells form a pellet at the bottom of the column. Anti- human globulin reagents were incorporated in the diluent and the new test system, column agglutination technology, was compared to conventional tube tests and low-ionic-strength method. Sera and plasmas (228 samples) were screened for red cell antibodies with two anti-human globulin reagents: one containing only anti-IgG and the other containing both anti-IgG and anti-C3b, -C3d. After initial testing, there was 94-percent agreement between column agglutination technology and tube tests, and after repeat testing, there was 97-percent agreement. The column agglutination technology anti-human globulin test eliminates the need to wash red cells, which decreases the overall test time. The test is easy to perform, and the results are more objective than those with tube and microplate methods.  相似文献   
553.
Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract involving aberrant activation of innate and adaptive immune responses. We have used two complementary models of IBD to examine the roles of interleukin (IL)-12 family cytokines in bacterially induced intestinal inflammation. Our results clearly show that IL-23, but not IL-12, is essential for the induction of chronic intestinal inflammation mediated by innate or adaptive immune mechanisms. Depletion of IL-23 was associated with decreased proinflammatory responses in the intestine but had little impact on systemic T cell inflammatory responses. These results newly identify IL-23 as a driver of innate immune pathology in the intestine and suggest that selective targeting of IL-23 represents an attractive therapeutic approach in human IBD.  相似文献   
554.
Lorenz  HM; Lagoo  AS; Hardy  KJ 《Blood》1994,83(7):1862-1870
We recently reported that cross-linking the leukocyte common antigen (CD45) can rapidly induce aggregation of human peripheral blood mononuclear cells via lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) interactions. Herein, we have examined both T-cell--monocyte cellular interactions and the molecular signaling that are involved in this phenomenon. Experiments using highly purified T lymphocytes showed that CD45-induced aggregation requires the presence of both T cells and monocytes. Cross- linking CD45 only on T lymphocytes, but not on monocytes, initiated cellular clustering after reconstituting to the respective untreated cell type. By several criteria, CD45-induced clustering of T cells to autologous monocytes was shown to be Fc-receptor--independent. When comparing intracellular signaling in leukocyte aggregation induced by CD45 cross-linking versus phorbol myristate-12-13-acetate (PMA) treatment, the former was found to be fivefold to 10-fold more sensitive to H-8, a reagent that effectively blocks cAMP- and cGMP- dependent protein kinases. On the other hand, reagents that increase intracellular cAMP levels (eg, dbcAMP, forskolin, and IBMX), protein kinase C (PKC) inhibitors (eg, staurosporine), and tyrosine kinase inhibitors (eg, herbimycin A and genistein) all readily inhibited PMA- induced, but not CD45 monoclonal antibody-induced, aggregation. We conclude that cross-linking the leukocyte common antigen on T cells induces LFA-1--/ICAM-1--dependent T-cell--monocyte aggregation through a unique signaling pathway independent of PKC, which involves instead cAMP-/cGMP-dependent protein kinases.  相似文献   
555.
目的:游离足趾移植是拇指Ⅱ类以上缺损再造术的首选。分析与Ⅱ趾移植相关的足部供血系统的血管走行、分支情况及变异程度,并提出临床应用中为保证手术成功而采取的相应对策。方法:对1978—03/2007—06天津医院手、显微外科收治的91例Ⅱ趾移植再造拇(手)指患者进行回顾性分析,所有病例均为ⅡB-ⅢB类型拇指缺损,均为择期手术,对治疗方案知情同意。术中遇第一跖背动脉纤细型,采取足背动脉-足底深支-第一跖底动脉的第2套供血系统。当第一跖背动脉走行不定而误伤时,手术继续进行,完整切取Ⅱ趾后,进行第一跖背动脉吻合修复。注意第一跖背动脉至足趾的分支解剖特点,辨清与Ⅱ趾的关系,采取不同的手术对策。结果:91例拇指缺损患者获得了97.8%的成活率及优良的外形与功能恢复,移植术中Ⅱ趾的使用率是100%。Ⅱ趾的血供系统特点:①由足背动脉发出的第二跖背动脉很少见,足背动脉的弓状动脉分支也很少见。②第一跖背动脉起始、走行、口径虽不恒定,但是有章可循。③第一跖背动脉终末交通支及至Ⅱ趾的分支情况分为3型,各型对Ⅱ趾的血供也有其不同特点。结论:全面掌握与Ⅱ趾移植相关的足部供血系统的解剖特点,术中仔细游离并采取相应的处理方法,是保证手术成功的关键。  相似文献   
556.
目的:应用经胸彩色多普勒超声技术评价自主研制的镍钛记忆合金左心耳封堵器封闭左心耳对实验动物猪左心房、左心室功能的影响。方法:实验于2005-09/2006-08在南京医科大学第一附属医院江苏省实验动物中心完成。①实验分组:选用苏钟小型种猪17只,随机分为实验组12只和对照组5只。②实验干预:实验组12只苏钟小型种猪使用自主研制的左心耳封堵器(发明专利号码:200610037789.3,公开号CN1799521,由镍钛合金骨架、多聚四氟乙烯膜和传送连接部分等构成。其外观呈单盘状,封堵器的左心房面呈圆盘状,直接连接放入心耳内的圆柱体结构)行左心耳封堵,对照组5只手术步骤相同而不采用封堵器行左心耳封堵。③实验评估:两组动物分别于术前、术后1周、2周、4周采用经胸超声心动图检查观察心功能的改变,测量左心房内径、最大及最小容积、左房射血分数、左心房搏出量、血流分数等左房功能参数以及左室射血分数、左室短轴缩短率、Tei指数、E/A比值等指标。结果:①实验动物数量分析:在施行左心耳封堵后,1头猪于术中出血过多并出现室颤后死亡,1头猪因封堵器脱入左房,卡在二尖瓣口导致死亡。其余动物封堵效果良好。②两组动物术后1,2,4周左房功能指标各参数与术前比较无明显变化(P>0.05);与术前相比,实验组术后1周、2周左室射血分数、左心室短轴缩短率、E/A比值分别由术前的0.70±0.04、0.39±0.03、1.33±0.28降低至术后1周的0.59±0.05、0.31±0.03、0.95±0.11(P<均0.01)及术后2周的0.62±0.05、0.33±0.05、0.90±0.05(P<均0.01);Tei指数由术前的0.48±0.02增加至术后1周的0.59±0.03(P<0.01)及术后2周的0.58±0.04(P<0.01)。对照组手术前后左室功能指标差异无显著性。结论:自主研制左心耳封堵器可以有效的封堵左心耳;左心耳封堵后短期内对实验动物左房功能无明显影响;封堵后短期内对左心室功能具有短期的减弱,更长期的安全性有待于进一步研究。  相似文献   
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