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   3622072篇
  免费   262603篇
  国内免费   9517篇
耳鼻咽喉   48987篇
儿科学   120192篇
妇产科学   99648篇
基础医学   510095篇
口腔科学   102409篇
临床医学   332125篇
内科学   707333篇
皮肤病学   85495篇
神经病学   293850篇
特种医学   137634篇
外国民族医学   941篇
外科学   541773篇
综合类   77884篇
现状与发展   8篇
一般理论   1419篇
预防医学   277616篇
眼科学   84108篇
药学   264780篇
  12篇
中国医学   8004篇
肿瘤学   199879篇
  2019年   28887篇
  2018年   41110篇
  2017年   31334篇
  2016年   35657篇
  2015年   40396篇
  2014年   55911篇
  2013年   83574篇
  2012年   112675篇
  2011年   119294篇
  2010年   71440篇
  2009年   67816篇
  2008年   111104篇
  2007年   118252篇
  2006年   119769篇
  2005年   114997篇
  2004年   110618篇
  2003年   106364篇
  2002年   102805篇
  2001年   175865篇
  2000年   179984篇
  1999年   151428篇
  1998年   43132篇
  1997年   38020篇
  1996年   38112篇
  1995年   36933篇
  1994年   33757篇
  1993年   31641篇
  1992年   117175篇
  1991年   112997篇
  1990年   109377篇
  1989年   105654篇
  1988年   96616篇
  1987年   94641篇
  1986年   88872篇
  1985年   84856篇
  1984年   63301篇
  1983年   53707篇
  1982年   31539篇
  1981年   28140篇
  1979年   55968篇
  1978年   39315篇
  1977年   33462篇
  1976年   31183篇
  1975年   33020篇
  1974年   39364篇
  1973年   37637篇
  1972年   35133篇
  1971年   32601篇
  1970年   30136篇
  1969年   28793篇
排序方式: 共有10000条查询结果,搜索用时 396 毫秒
61.
Introduction: In men, lower urinary tract symptoms (LUTS) are primarily attributed to benign prostatic hyperplasia (BPH). Therapeutic options are targeted to relax prostate smooth muscle and/or reduce prostate enlargement.

Areas covered: This article reviews the major preclinical and clinical data on PDE5 inhibitors with a specific focus on tadalafil. It includes details of the role of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) – PDE5 pathway in the LUT organs (bladder and prostate) in addition to the available data on tadalafil in patients with LUTS secondary to BPH with or without erectile dysfunction (ED).

Expert opinion: Preclinical and clinical data have clearly demonstrated that PDE5 inhibitors induce bladder and prostate relaxation, which contributes to the improvement seen in storage symptoms in both animal models of bladder and prostate hypercontractility. Tadalafil is effective both as a monotherapy and add-on therapy in patients with LUTS secondary to BPH. Furthermore, as LUTS-BPH and ED are urological disorders that commonly coexist in aging men, tadalafil is more advantageous than α1-adrenoceptors and should be used as the first option. Tadalafil is a safe and tolerable therapy and unlike α1- adrenoceptors and 5-alpha reductase inhibitors, which can cause sexual dysfunctions, tadalafil improves sexual function.  相似文献   

62.
63.
64.
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   
65.
66.
67.
68.
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   
69.
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   
70.
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