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   1408146篇
  免费   115788篇
  国内免费   3330篇
耳鼻咽喉   18359篇
儿科学   46613篇
妇产科学   41051篇
基础医学   200752篇
口腔科学   37754篇
临床医学   125949篇
内科学   284133篇
皮肤病学   33352篇
神经病学   116847篇
特种医学   53830篇
外国民族医学   464篇
外科学   210557篇
综合类   32767篇
现状与发展   3篇
一般理论   489篇
预防医学   109975篇
眼科学   31446篇
药学   98495篇
  1篇
中国医学   3347篇
肿瘤学   81080篇
  2021年   10861篇
  2019年   11670篇
  2018年   16594篇
  2017年   12683篇
  2016年   14265篇
  2015年   16021篇
  2014年   22571篇
  2013年   33420篇
  2012年   45423篇
  2011年   47971篇
  2010年   28172篇
  2009年   27067篇
  2008年   44357篇
  2007年   46859篇
  2006年   47436篇
  2005年   45897篇
  2004年   43792篇
  2003年   41720篇
  2002年   40219篇
  2001年   73026篇
  2000年   74551篇
  1999年   61583篇
  1998年   17009篇
  1997年   15432篇
  1996年   15591篇
  1995年   14796篇
  1994年   13396篇
  1993年   12589篇
  1992年   45854篇
  1991年   43494篇
  1990年   41499篇
  1989年   39556篇
  1988年   36193篇
  1987年   35368篇
  1986年   32871篇
  1985年   31287篇
  1984年   23831篇
  1983年   20027篇
  1982年   12210篇
  1981年   10780篇
  1979年   20703篇
  1978年   14578篇
  1977年   12085篇
  1976年   11365篇
  1975年   11621篇
  1974年   13989篇
  1973年   13533篇
  1972年   12633篇
  1971年   11471篇
  1970年   10911篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Metabolism describes the series of chemical reactions that are concerned with the provision of energy to biological systems. They may be divided into reactions involved in energy yield (catabolism: demand exceeds supply), and energy storage (anabolism: supply exceeds demand). Regulation of these pathways is critical for homeostasis, and derangements in metabolism are seen in a wide variety of pathological processes. Understanding metabolism is key to the treatment of many diseases, notably diabetes, as well as underpinning clinical nutritional support.  相似文献   
32.
33.
34.
35.
36.
We report on a child with several café au lait spots in association with a lumbar lipomeningomyelocele as an apparently new association. Cutaneous markers, the identification of which plays a crucial role in the early diagnosis and management of spinal malformations, can accompany occult spinal dysraphism. Herein we report a case of lumbar lipomeningomyelocele associated with an overlying café au lait spot that served as a marker of occult spinal dysraphism. The patient also had segmental café au lait spots on the face, making the association unique.  相似文献   
37.
38.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
39.
40.
Bipolar disorder (BD) is a common psychiatric mood disorder affecting more than 1-2% of the general population of different European countries. Unfortunately, there is no objective laboratory-based test to aid BD diagnosis or monitor its progression, and little is known about the molecular basis of BD. Here, we performed a comparative proteomic study to identify differentially expressed plasma proteins in various BD mood states (depressed BD, manic BD, and euthymic BD) relative to healthy controls. A total of 10 euthymic BD, 20 depressed BD, 15 manic BD, and 20 demographically matched healthy control subjects were recruited. Seven high-abundance proteins were immunodepleted in plasma samples from the 4 experimental groups, which were then subjected to proteome-wide expression profiling by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight tandem mass spectrometry. Proteomic results were validated by immunoblotting and bioinformatically analyzed using MetaCore. From a total of 32 proteins identified with 1.5-fold changes in expression compared with healthy controls, 16 proteins were perturbed in BD independent of mood state, while 16 proteins were specifically associated with particular BD mood states. Two mood-independent differential proteins, apolipoprotein (Apo) A1 and Apo L1, suggest that BD pathophysiology may be associated with early perturbations in lipid metabolism. Moreover, down-regulation of one mood-dependent protein, carbonic anhydrase 1 (CA-1), suggests it may be involved in the pathophysiology of depressive episodes in BD. Thus, BD pathophysiology may be associated with early perturbations in lipid metabolism that are independent of mood state, while CA-1 may be involved in the pathophysiology of depressive episodes.  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