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   1408846篇
  免费   115729篇
  国内免费   3331篇
耳鼻咽喉   18361篇
儿科学   46557篇
妇产科学   41049篇
基础医学   200784篇
口腔科学   37701篇
临床医学   126070篇
内科学   284386篇
皮肤病学   33361篇
神经病学   116870篇
特种医学   53857篇
外国民族医学   464篇
外科学   210635篇
综合类   32760篇
现状与发展   3篇
一般理论   487篇
预防医学   110039篇
眼科学   31501篇
药学   98522篇
  1篇
中国医学   3347篇
肿瘤学   81151篇
  2021年   10858篇
  2019年   11676篇
  2018年   16589篇
  2017年   12680篇
  2016年   14262篇
  2015年   16016篇
  2014年   22573篇
  2013年   33408篇
  2012年   45402篇
  2011年   47933篇
  2010年   28160篇
  2009年   27050篇
  2008年   44323篇
  2007年   46834篇
  2006年   47388篇
  2005年   45858篇
  2004年   43754篇
  2003年   41695篇
  2002年   40186篇
  2001年   73002篇
  2000年   74532篇
  1999年   61565篇
  1998年   16987篇
  1997年   15430篇
  1996年   15585篇
  1995年   14790篇
  1994年   13395篇
  1993年   12581篇
  1992年   45840篇
  1991年   43482篇
  1990年   41493篇
  1989年   39558篇
  1988年   36187篇
  1987年   35362篇
  1986年   32869篇
  1985年   31287篇
  1984年   23829篇
  1983年   20029篇
  1982年   12212篇
  1981年   10783篇
  1979年   20705篇
  1978年   14579篇
  1977年   12091篇
  1976年   11370篇
  1975年   11622篇
  1974年   13998篇
  1973年   13543篇
  1972年   12640篇
  1971年   11479篇
  1970年   10914篇
排序方式: 共有10000条查询结果,搜索用时 27 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