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   2595654篇
  免费   204823篇
  国内免费   6316篇
耳鼻咽喉   34886篇
儿科学   86216篇
妇产科学   73040篇
基础医学   375244篇
口腔科学   74929篇
临床医学   241391篇
内科学   499771篇
皮肤病学   54259篇
神经病学   213522篇
特种医学   99255篇
外国民族医学   804篇
外科学   378307篇
综合类   62374篇
现状与发展   4篇
一般理论   958篇
预防医学   212744篇
眼科学   59019篇
药学   194564篇
  8篇
中国医学   5426篇
肿瘤学   140072篇
  2018年   27425篇
  2017年   21052篇
  2016年   23208篇
  2015年   26680篇
  2014年   36780篇
  2013年   56794篇
  2012年   77287篇
  2011年   81940篇
  2010年   48077篇
  2009年   45117篇
  2008年   76630篇
  2007年   80917篇
  2006年   81550篇
  2005年   79199篇
  2004年   76785篇
  2003年   73230篇
  2002年   71595篇
  2001年   117036篇
  2000年   120927篇
  1999年   102094篇
  1998年   28870篇
  1997年   26250篇
  1996年   25975篇
  1995年   25102篇
  1994年   23586篇
  1993年   22279篇
  1992年   83446篇
  1991年   81654篇
  1990年   79484篇
  1989年   76326篇
  1988年   71014篇
  1987年   69679篇
  1986年   66453篇
  1985年   63983篇
  1984年   48119篇
  1983年   41350篇
  1982年   24725篇
  1981年   22017篇
  1979年   45165篇
  1978年   31736篇
  1977年   26572篇
  1976年   25363篇
  1975年   26586篇
  1974年   32493篇
  1973年   31457篇
  1972年   28955篇
  1971年   27188篇
  1970年   25064篇
  1969年   23279篇
  1968年   21761篇
排序方式: 共有10000条查询结果,搜索用时 578 毫秒
71.
72.
73.
Owing to the frequent incidence of blast-induced traumatic brain injury (bTBI) in recent military conflicts, there is an urgent need to develop effective therapies for bTBI-related pathologies. Blood-brain barrier (BBB) breakdown has been reported to occur after primary blast exposure, making restoration of BBB function and integrity a promising therapeutic target. We tested the hypothesis that treatment with dexamethasone (DEX) after primary blast injury potentiates recovery of an in vitro BBB model consisting of mouse brain endothelial cells (bEnd.3). DEX treatment resulted in complete recovery of transendothelial electrical resistance and hydraulic conductivity 1 day after injury, compared with 3 days for vehicle-treated injured cultures. Administration of RU486 (mifepristone) inhibited effects of DEX, confirming that barrier restoration was mediated by glucocorticoid receptor signaling. Potentiated recovery with DEX treatment was accompanied by stronger zonula occludens (ZO)-1 tight junction immunostaining and expression, suggesting that increased ZO-1 expression was a structural correlate to BBB recovery after blast. Interestingly, augmented ZO-1 protein expression was associated with specific upregulation of the α+ isoform but not the α isoform. This is the first study to provide a mechanistic basis for potentiated functional recovery of an in vitro BBB model because of glucocorticoid treatment after primary blast injury.  相似文献   
74.
75.
76.
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   
77.
78.
79.
80.
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