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   10540篇
  免费   1411篇
  国内免费   66篇
耳鼻咽喉   157篇
儿科学   388篇
妇产科学   206篇
基础医学   1270篇
口腔科学   854篇
临床医学   981篇
内科学   2373篇
皮肤病学   394篇
神经病学   621篇
特种医学   465篇
外科学   1654篇
综合类   336篇
一般理论   4篇
预防医学   602篇
眼科学   229篇
药学   661篇
  1篇
中国医学   47篇
肿瘤学   774篇
  2023年   97篇
  2022年   282篇
  2021年   485篇
  2020年   349篇
  2019年   544篇
  2018年   612篇
  2017年   475篇
  2016年   532篇
  2015年   466篇
  2014年   591篇
  2013年   746篇
  2012年   704篇
  2011年   813篇
  2010年   552篇
  2009年   402篇
  2008年   487篇
  2007年   482篇
  2006年   415篇
  2005年   417篇
  2004年   382篇
  2003年   309篇
  2002年   268篇
  2001年   177篇
  2000年   153篇
  1999年   136篇
  1998年   101篇
  1997年   83篇
  1996年   88篇
  1995年   63篇
  1994年   47篇
  1993年   51篇
  1992年   43篇
  1991年   30篇
  1990年   33篇
  1989年   54篇
  1988年   62篇
  1987年   65篇
  1986年   63篇
  1985年   55篇
  1984年   37篇
  1983年   22篇
  1982年   28篇
  1981年   25篇
  1980年   18篇
  1979年   15篇
  1978年   13篇
  1977年   21篇
  1976年   15篇
  1975年   17篇
  1966年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Despite recent advances in surgical technique using laparoscopic and robotic approaches for the management of early organ-confined prostate cancer, most contemporary reports demonstrate significant rates of erectile dysfunction comparable to standard open approaches. Controversy remains related to many of the pre-and postoperative management strategies, including agents to enhance nerve recovery, erectogenic drugs, antioxidants, vasoactive injectables, vacuum erection devices and nerve grafting procedures. Additionally, the optimal timing of these interventions and their duration, dose, frequency and outcome thresholds remain ill-defined. In our paper, we provide a comprehensive literature review involving both the basic and clinical data surrounding rehabilitative approaches.  相似文献   
52.
Erythrocyte protoporphyrin and blood lead concentrations were measured in samples from 583 Saudi children attending the outpatient clinics. Erythrocyte protoporphyrin concentrations showed poor correlation with blood lead concentrations of 25 ug dl?1 and below. Measurement of erythrocyte protoporphyrin as a primary test for lead exposure is not recommended.  相似文献   
53.
54.
55.
A consecutive series of 47 hospitalized cases of Guillain-Barré syndrome seen over a 10-year period was analysed with respect to: (1) age and sex; (2) antecedent events and seasonal distribution; (3) patterns of clinical presentation; (4) CSF and neurophysiological findings; (5) results of treatment with plasma exchange; and (6) outcome. Twenty-two were children, 20 middle-aged and 5 aged; 37 were male and 10 were female. The most frequent antecedent event was upper respiratory tract infections; a seasonal peak incidence was found in winter. Clinical, CSF and neurophysiological findings concurred with those in the Western literature; 79% of the cases were severe. Plasma exchange performed within the first 2 weeks of onset benefitted in the short-term outcome, i.e. improvement by 1 grade at 4 weeks, but the long-term benefit, i.e. the ability to regain independent locomotion, was questionable. Plasma exchange helped in curtailing the time to walking unaided but had no benefit on the duration of artificial ventilation. Factors associated with an adverse outcome were: age over 15 years, severity of motor electrodiagnostic findings (especially a decreased distal CMAP amplitude and EMG signs of acute denervation), requirement for ventilation and slow progression (>3 weeks) to maximum deficit. After a mean follow-up of 11 months, 55% of the patients regained independent locomotion, which is a comparatively low proportion.  相似文献   
56.
57.
58.
59.
60.
Although displaying similar amounts of surface IgM and IgD, ECH 408-1 cells only succumb to apoptosis after cross-linking of IgM (not IgD), suggesting that different signaling pathways couple to both receptors. Immunoprecipitation studies revealed the presence of several proteins selectively associated with IgM and IgD, thus ruling out that the lack of inhibitory signaling mediated by IgD might be due to membrane expression in the absence of associated proteins belonging to the B cell receptor complex. 32P metabolic labeling and immunoprecipitation studies demonstrated that IgM and IgD are associated with phosphoproteins of 32-33 kDa in an isotype-specific fashion. Kinetic analyses of tyrosine kinase activity showed that cross-linking of surface IgM or IgD resulted in the rapid (1-3 min) phosphorylation of several protein substrates on tyrosine residues, followed by a dephosphorylation step. Isotype-specific changes of the phosphorylation status specifically affected molecules in the 32-33 kDa range, i.e. IgM (not IgD) cross-linking affected a approximately 32-kDa protein, whereas IgD (not IgM) cross-linking induced phosphorylation of a protein exhibiting a slightly lower mobility (33 kDa). These results suggest that isotype-specific immunoglobulin-associated molecules could be involved in the second messenger cascade leading to different biological effects upon IgM and IgD cross-linking.  相似文献   
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