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   2544257篇
  免费   189602篇
  国内免费   4010篇
耳鼻咽喉   35970篇
儿科学   83557篇
妇产科学   71176篇
基础医学   361527篇
口腔科学   74992篇
临床医学   224471篇
内科学   487175篇
皮肤病学   56455篇
神经病学   202719篇
特种医学   102949篇
外国民族医学   685篇
外科学   388405篇
综合类   57521篇
现状与发展   4篇
一般理论   802篇
预防医学   187620篇
眼科学   59316篇
药学   196134篇
  9篇
中国医学   5418篇
肿瘤学   140964篇
  2018年   25573篇
  2017年   20224篇
  2016年   23080篇
  2015年   26298篇
  2014年   35215篇
  2013年   52810篇
  2012年   72458篇
  2011年   75935篇
  2010年   44841篇
  2009年   42000篇
  2008年   72186篇
  2007年   76697篇
  2006年   77993篇
  2005年   75680篇
  2004年   73782篇
  2003年   70714篇
  2002年   68886篇
  2001年   122902篇
  2000年   126589篇
  1999年   106812篇
  1998年   28486篇
  1997年   25426篇
  1996年   25174篇
  1995年   24172篇
  1994年   22412篇
  1993年   21155篇
  1992年   84366篇
  1991年   81652篇
  1990年   80144篇
  1989年   77414篇
  1988年   71291篇
  1987年   70128篇
  1986年   66476篇
  1985年   63724篇
  1984年   47121篇
  1983年   40367篇
  1982年   23238篇
  1981年   20592篇
  1979年   44266篇
  1978年   30503篇
  1977年   26240篇
  1976年   24056篇
  1975年   26161篇
  1974年   31410篇
  1973年   30229篇
  1972年   28315篇
  1971年   26652篇
  1970年   24458篇
  1969年   23188篇
  1968年   21107篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
61.
62.
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   
63.
64.
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   
65.
66.
67.
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   
68.
69.
70.
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