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   2829021篇
  免费   213628篇
  国内免费   6121篇
耳鼻咽喉   37857篇
儿科学   93954篇
妇产科学   78014篇
基础医学   402807篇
口腔科学   80992篇
临床医学   256002篇
内科学   553083篇
皮肤病学   65697篇
神经病学   228034篇
特种医学   107364篇
外国民族医学   696篇
外科学   426129篇
综合类   64376篇
现状与发展   7篇
一般理论   979篇
预防医学   215114篇
眼科学   66305篇
药学   204287篇
  7篇
中国医学   6746篇
肿瘤学   160320篇
  2021年   21709篇
  2019年   22989篇
  2018年   33692篇
  2017年   25702篇
  2016年   28933篇
  2015年   31920篇
  2014年   44159篇
  2013年   66312篇
  2012年   90625篇
  2011年   96435篇
  2010年   56620篇
  2009年   52413篇
  2008年   89749篇
  2007年   95292篇
  2006年   95860篇
  2005年   92459篇
  2004年   88720篇
  2003年   84901篇
  2002年   82016篇
  2001年   141399篇
  2000年   145627篇
  1999年   119809篇
  1998年   33343篇
  1997年   29314篇
  1996年   29245篇
  1995年   27918篇
  1994年   25508篇
  1993年   23745篇
  1992年   90243篇
  1991年   86554篇
  1990年   83273篇
  1989年   79977篇
  1988年   73183篇
  1987年   71572篇
  1986年   67007篇
  1985年   64005篇
  1984年   47908篇
  1983年   40538篇
  1982年   23865篇
  1981年   21261篇
  1979年   42192篇
  1978年   29466篇
  1977年   24886篇
  1976年   23375篇
  1975年   24311篇
  1974年   29338篇
  1973年   28244篇
  1972年   26296篇
  1971年   24165篇
  1970年   22779篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
41.
42.
43.
44.
45.
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild...  相似文献   
46.
47.
48.
Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality.  相似文献   
49.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
50.
Krishna S. Iyer 《Platelets》2020,31(4):474-482
Abstract

Platelets are small, anucleated effector cells that play an important role in linking the hemostatic and inflammatory processes in the body. Platelet function is known to be altered under various inflammatory conditions including aging. A gain in platelet function during aging can increase the risk of thrombotic events, such as stroke and acute myocardial infarction. Anti-platelet therapy is designed to reduce risk of serious cerebrovascular and cardiovascular events, but the adverse consequences of therapy, such as risk for bleeding increases with aging as well. Age-associated comorbidities such as obesity, diabetes, and hyperlipidemia also contribute to increased platelet activity and thus can enhance the risk of thrombosis. Therefore, identification of unique mechanisms of platelet dysfunction in aging and in age-associated comorbidities is warranted to design novel antiplatelet drugs. This review outlines some of the current areas of research on aging-related mechanisms of platelet hyperactivity and addresses the clinical urgency for designing anti-platelet therapies toward novel molecular targets in the aging population.  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