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   76588篇
  免费   44718篇
  国内免费   229篇
耳鼻咽喉   1521篇
儿科学   4276篇
妇产科学   560篇
基础医学   15832篇
口腔科学   5191篇
临床医学   12615篇
内科学   23437篇
皮肤病学   7462篇
神经病学   13352篇
特种医学   2423篇
外国民族医学   1篇
外科学   14146篇
综合类   521篇
现状与发展   2篇
一般理论   21篇
预防医学   4500篇
眼科学   1270篇
药学   5883篇
  1篇
中国医学   1207篇
肿瘤学   7314篇
  2023年   68篇
  2022年   172篇
  2021年   1397篇
  2020年   5146篇
  2019年   10892篇
  2018年   10152篇
  2017年   11535篇
  2016年   12183篇
  2015年   12035篇
  2014年   11988篇
  2013年   12444篇
  2012年   4308篇
  2011年   4251篇
  2010年   9046篇
  2009年   5391篇
  2008年   2186篇
  2007年   1030篇
  2006年   1036篇
  2005年   816篇
  2004年   769篇
  2003年   788篇
  2002年   880篇
  2001年   843篇
  2000年   762篇
  1999年   330篇
  1998年   75篇
  1997年   54篇
  1996年   48篇
  1995年   38篇
  1994年   51篇
  1993年   37篇
  1992年   65篇
  1991年   51篇
  1990年   47篇
  1989年   56篇
  1988年   47篇
  1987年   60篇
  1986年   51篇
  1985年   54篇
  1984年   36篇
  1983年   29篇
  1982年   28篇
  1981年   25篇
  1980年   18篇
  1979年   33篇
  1978年   25篇
  1977年   18篇
  1975年   14篇
  1974年   19篇
  1970年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
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   
102.
103.
104.
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   
105.
106.
107.
108.
109.
110.
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