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   1709583篇
  免费   121218篇
  国内免费   3411篇
耳鼻咽喉   24298篇
儿科学   49912篇
妇产科学   46488篇
基础医学   242334篇
口腔科学   50000篇
临床医学   145560篇
内科学   339773篇
皮肤病学   35974篇
神经病学   134119篇
特种医学   68153篇
外国民族医学   411篇
外科学   274414篇
综合类   34705篇
现状与发展   1篇
一般理论   469篇
预防医学   119022篇
眼科学   39193篇
药学   127390篇
  3篇
中国医学   3668篇
肿瘤学   98325篇
  2018年   16636篇
  2017年   13108篇
  2016年   14255篇
  2015年   16215篇
  2014年   22601篇
  2013年   34208篇
  2012年   46197篇
  2011年   48698篇
  2010年   29249篇
  2009年   28025篇
  2008年   47383篇
  2007年   49790篇
  2006年   50735篇
  2005年   49352篇
  2004年   47500篇
  2003年   45824篇
  2002年   45052篇
  2001年   88312篇
  2000年   91179篇
  1999年   76773篇
  1998年   19384篇
  1997年   17432篇
  1996年   17385篇
  1995年   16201篇
  1994年   15309篇
  1993年   14190篇
  1992年   59103篇
  1991年   56639篇
  1990年   55025篇
  1989年   53382篇
  1988年   48969篇
  1987年   48095篇
  1986年   45344篇
  1985年   43287篇
  1984年   31528篇
  1983年   26779篇
  1982年   14926篇
  1981年   13053篇
  1979年   28591篇
  1978年   19617篇
  1977年   16712篇
  1976年   15114篇
  1975年   16661篇
  1974年   20108篇
  1973年   19033篇
  1972年   18107篇
  1971年   16904篇
  1970年   16262篇
  1969年   15240篇
  1968年   14177篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
31.
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   
32.
33.
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (Pacnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety.  相似文献   
34.
35.
36.
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   
37.
38.
39.
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   
40.
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