首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1496篇
  免费   106篇
  国内免费   7篇
耳鼻咽喉   7篇
儿科学   57篇
妇产科学   8篇
基础医学   135篇
口腔科学   30篇
临床医学   203篇
内科学   251篇
皮肤病学   303篇
神经病学   49篇
特种医学   258篇
外科学   95篇
综合类   27篇
预防医学   78篇
眼科学   9篇
药学   40篇
中国医学   5篇
肿瘤学   54篇
  2023年   10篇
  2021年   16篇
  2020年   8篇
  2019年   14篇
  2018年   34篇
  2017年   16篇
  2016年   24篇
  2015年   27篇
  2014年   41篇
  2013年   37篇
  2012年   30篇
  2011年   38篇
  2010年   49篇
  2009年   76篇
  2008年   50篇
  2007年   32篇
  2006年   30篇
  2005年   21篇
  2004年   24篇
  2003年   22篇
  2002年   21篇
  2001年   30篇
  2000年   16篇
  1999年   19篇
  1998年   54篇
  1997年   56篇
  1996年   71篇
  1995年   55篇
  1994年   49篇
  1993年   49篇
  1992年   45篇
  1991年   21篇
  1990年   44篇
  1989年   58篇
  1988年   47篇
  1987年   48篇
  1986年   48篇
  1985年   44篇
  1984年   36篇
  1983年   20篇
  1982年   26篇
  1981年   19篇
  1980年   13篇
  1979年   10篇
  1978年   8篇
  1977年   14篇
  1976年   18篇
  1975年   17篇
  1972年   8篇
  1971年   9篇
排序方式: 共有1609条查询结果,搜索用时 0 毫秒
91.
The effect of barium on blood in the gastrointestinal tract   总被引:2,自引:0,他引:2  
  相似文献   
92.
The effect of atracurium 0.6 mg/kg (group A; n = 11) and fazadinium 1 mg/kg (group F; n = 11) on intraocular pressure (IOP) was investigated in 22 patients during induction of anaesthesia with thiopentone 4 mg/kg and fentanyl 0.015 mg/kg. IOP was significantly reduced (p less than 0.01) in all patients following induction of anaesthesia. Intubation produced a rise in IOP in all patients but this was not statistically significant and remained below pre-induction values. The changes were similar in each group. Both of these neuromuscular blockers appear suitable relaxants to use for intraocular surgery.  相似文献   
93.
94.
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异.  相似文献   
95.
Two patients with suprasellar cysts and hyperprolactinemia are described. These lesions were diagnosed by CT metrizamide cisternography. Suprasellar cysts are a rare cause of pathologic hyperprolactinemia, which most commonly results from pituitary adenomas. Tissue diagnosis revealed suprasellar arachnoid cysts in the first patient and Rathke's cleft cyst in the second. The differential diagnosis of suprasellar cysts is presented, and distinguishing radiographic characteristics are discussed.  相似文献   
96.
97.
98.
Rybak  ME; Gimbrone  MA Jr; Davies  PF; Handin  RI 《Blood》1989,73(6):1534-1539
Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function.  相似文献   
99.
Rothko  K; Kickler  TS; Clay  ME; Johnson  RJ; Stroncek  DF 《Blood》1989,74(5):1698-1703
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia.  相似文献   
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号