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   132789篇
  免费   49731篇
  国内免费   4589篇
耳鼻咽喉   1866篇
儿科学   4987篇
妇产科学   1212篇
基础医学   22408篇
口腔科学   6100篇
临床医学   20200篇
内科学   31631篇
皮肤病学   7926篇
神经病学   15766篇
特种医学   4487篇
外国民族医学   40篇
外科学   20024篇
综合类   10824篇
现状与发展   15篇
一般理论   27篇
预防医学   8126篇
眼科学   2770篇
药学   11986篇
  58篇
中国医学   4567篇
肿瘤学   12089篇
  2024年   208篇
  2023年   1014篇
  2022年   2642篇
  2021年   4552篇
  2020年   7309篇
  2019年   12675篇
  2018年   11960篇
  2017年   13214篇
  2016年   13773篇
  2015年   14493篇
  2014年   15015篇
  2013年   15145篇
  2012年   8213篇
  2011年   8812篇
  2010年   11803篇
  2009年   7544篇
  2008年   5015篇
  2007年   4050篇
  2006年   3911篇
  2005年   3583篇
  2004年   2840篇
  2003年   2870篇
  2002年   2670篇
  2001年   2410篇
  2000年   2229篇
  1999年   1732篇
  1998年   892篇
  1997年   969篇
  1996年   695篇
  1995年   644篇
  1994年   563篇
  1993年   369篇
  1992年   464篇
  1991年   441篇
  1990年   419篇
  1989年   347篇
  1988年   283篇
  1987年   250篇
  1986年   234篇
  1985年   167篇
  1984年   121篇
  1983年   66篇
  1982年   44篇
  1981年   40篇
  1980年   38篇
  1979年   65篇
  1978年   33篇
  1975年   33篇
  1974年   41篇
  1973年   24篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  相似文献   
122.
123.
124.
Capillary malformation–arteriovenous malformation syndrome (CM‐AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM‐AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM‐AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM‐AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature.  相似文献   
125.
126.
127.
128.
129.
130.
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