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   2113846篇
  免费   171522篇
  国内免费   7617篇
耳鼻咽喉   27453篇
儿科学   70485篇
妇产科学   58651篇
基础医学   298152篇
口腔科学   59055篇
临床医学   192490篇
内科学   422781篇
皮肤病学   49689篇
神经病学   171875篇
特种医学   84751篇
外国民族医学   579篇
外科学   324583篇
综合类   50636篇
现状与发展   2篇
一般理论   762篇
预防医学   169107篇
眼科学   46861篇
药学   150472篇
  7篇
中国医学   3863篇
肿瘤学   110731篇
  2018年   21714篇
  2016年   19950篇
  2015年   22345篇
  2014年   31144篇
  2013年   47192篇
  2012年   59721篇
  2011年   63775篇
  2010年   39184篇
  2009年   37598篇
  2008年   59613篇
  2007年   63522篇
  2006年   64744篇
  2005年   62559篇
  2004年   60202篇
  2003年   58302篇
  2002年   55696篇
  2001年   99706篇
  2000年   102385篇
  1999年   85758篇
  1998年   25384篇
  1997年   22761篇
  1996年   23557篇
  1995年   23414篇
  1994年   21760篇
  1993年   20338篇
  1992年   70572篇
  1991年   68863篇
  1990年   66696篇
  1989年   64054篇
  1988年   58994篇
  1987年   58442篇
  1986年   54929篇
  1985年   53116篇
  1984年   40342篇
  1983年   33954篇
  1982年   21006篇
  1981年   18949篇
  1980年   17769篇
  1979年   36754篇
  1978年   26708篇
  1977年   22426篇
  1976年   20975篇
  1975年   21850篇
  1974年   25998篇
  1973年   25037篇
  1972年   23098篇
  1971年   21366篇
  1970年   19706篇
  1969年   18483篇
  1968年   17131篇
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
61.
62.
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   
63.
Hepatic NADPH-cytochrome P450 oxidoreductase null (HRN?) mice exhibit normal hepatic and extrahepatic biotransformation enzyme activities when compared to wild-type (WT) mice, but express no functional hepatic cytochrome P450 activities. When incubated in vitro with [14C]-diclofenac, liver microsomes from WT mice exhibited extensive biotransformation to oxidative and glucuronide metabolites and covalent binding to proteins was also observed. In contrast, whereas glucuronide conjugates and a quinone-imine metabolite were formed when [14C]-diclofenac was incubated with HRN? mouse liver, only small quantities of P450-derived oxidative metabolites were produced in these samples and covalent binding to proteins was not observed. Livers from vehicle-treated HRN? mice exhibited enhanced lipid accumulation, bile duct proliferation, hepatocellular degeneration and necrosis and inflammatory cell infiltration, which were not present in livers from WT mice. Elevated liver-derived alanine aminotransferase, glutamate dehydrogenase and alkaline phosphatase activities were also observed in plasma from HRN? mice. When treated orally with diclofenac for 7 days, at 30 mg/kg/day, the severities of the abnormal liver histopathology and plasma liver enzyme findings in HRN? mice were reduced markedly. Oral diclofenac administration did not alter the liver histopathology or elevate plasma enzyme activities of WT mice. These findings indicate that HRN? mice are valuable for exploration of the role played by hepatic P450s in drug biotransformation, but poorly suited to investigations of drug-induced liver toxicity. Nevertheless, studies in HRN? mice could provide novel insights into the role played by inflammation in liver injury and may aid the evaluation of new strategies for its treatment.  相似文献   
64.
65.
66.
67.
68.
69.
70.
The current situation in which the humanities are disparaged affects all university disciplines, including nursing, in whose historical evolution the humanities have always been present in one form or another. Looking beyond this disrepute, this study proposes that nursing renew its attention to classical philosophy. Specifically, it invites a close reading of Xenophon's Anabasis and Plato's Meno, to get three related goals: to show how the use of ancient texts are very valuable tools for the philosophical initiation of nursing students and can help them reflect on their choice of nursing as a practical activity; to reflect on the problem of virtue and the nature of the good life; and to show how the interaction with ancient texts allows students to reflect on questions and issues of life, theirs and others, that are not open to investigation through a purely scientific method. Consequently, both Anabasis and Meno readings strengthen the intellectual relationship between philosophy and nursing, enabling the latter to delve deeper into the key questions of its own thought as a discipline.  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