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   1598953篇
  免费   133588篇
  国内免费   2575篇
耳鼻咽喉   21647篇
儿科学   52914篇
妇产科学   46223篇
基础医学   227787篇
口腔科学   47186篇
临床医学   140830篇
内科学   314477篇
皮肤病学   34101篇
神经病学   130066篇
特种医学   64727篇
外国民族医学   474篇
外科学   243815篇
综合类   39704篇
现状与发展   3篇
一般理论   544篇
预防医学   122725篇
眼科学   36427篇
药学   121245篇
  2篇
中国医学   2975篇
肿瘤学   87244篇
  2018年   14771篇
  2016年   12901篇
  2015年   15036篇
  2014年   20653篇
  2013年   31364篇
  2012年   42563篇
  2011年   44766篇
  2010年   26347篇
  2009年   25310篇
  2008年   43011篇
  2007年   45250篇
  2006年   46070篇
  2005年   44683篇
  2004年   44108篇
  2003年   42189篇
  2002年   41302篇
  2001年   75691篇
  2000年   78337篇
  1999年   66389篇
  1998年   17733篇
  1997年   16336篇
  1996年   16317篇
  1995年   16021篇
  1994年   15071篇
  1993年   14217篇
  1992年   55438篇
  1991年   53784篇
  1990年   52569篇
  1989年   50842篇
  1988年   47226篇
  1987年   46564篇
  1986年   44288篇
  1985年   42844篇
  1984年   32034篇
  1983年   27568篇
  1982年   16144篇
  1981年   14436篇
  1980年   13564篇
  1979年   30464篇
  1978年   21066篇
  1977年   17765篇
  1976年   16695篇
  1975年   17574篇
  1974年   21489篇
  1973年   20676篇
  1972年   18858篇
  1971年   17773篇
  1970年   16291篇
  1969年   15271篇
  1968年   13952篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
41.
42.
43.
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   
44.
45.
46.
47.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
48.
49.
50.
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