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   2528077篇
  免费   182543篇
  国内免费   4067篇
耳鼻咽喉   34154篇
儿科学   80615篇
妇产科学   66203篇
基础医学   370037篇
口腔科学   67294篇
临床医学   229599篇
内科学   493209篇
皮肤病学   54511篇
神经病学   203665篇
特种医学   95925篇
外国民族医学   501篇
外科学   381489篇
综合类   49488篇
现状与发展   13篇
一般理论   999篇
预防医学   195826篇
眼科学   58636篇
药学   187011篇
  12篇
中国医学   4825篇
肿瘤学   140675篇
  2021年   22821篇
  2019年   23184篇
  2018年   31567篇
  2017年   23618篇
  2016年   26436篇
  2015年   29843篇
  2014年   42221篇
  2013年   62478篇
  2012年   87455篇
  2011年   92715篇
  2010年   54634篇
  2009年   51692篇
  2008年   86484篇
  2007年   91994篇
  2006年   92494篇
  2005年   89882篇
  2004年   85821篇
  2003年   82188篇
  2002年   79402篇
  2001年   110273篇
  2000年   112636篇
  1999年   95102篇
  1998年   29081篇
  1997年   25353篇
  1996年   25516篇
  1995年   24063篇
  1994年   22093篇
  1993年   20880篇
  1992年   72798篇
  1991年   70837篇
  1990年   69051篇
  1989年   66256篇
  1988年   60851篇
  1987年   59623篇
  1986年   55731篇
  1985年   53579篇
  1984年   40007篇
  1983年   34042篇
  1982年   20682篇
  1979年   36268篇
  1978年   26082篇
  1977年   21606篇
  1976年   20687篇
  1975年   22098篇
  1974年   26417篇
  1973年   25049篇
  1972年   23363篇
  1971年   22181篇
  1970年   20374篇
  1969年   19399篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
Dear Sir In the recently published Task force report, under section ‘Fibrinolyticregimens’, the authors recommend not to re-administerstreptokinase for at least 10 years. The reference supportingthis statement is Ref. 51. After evaluating this paper and lookinginto the literature my comments  相似文献   
94.
OBJECTIVE: To determine whether under-reporting of rheumatic fever occurs at hospital, municipal, provincial and national levels of the South African health system. BACKGROUND: Information on the incidence of rheumatic fever (RF) and the prevalence of rheumatic heart disease (RHD) is required for the prevention of valvular heart disease in developing countries. In South Africa, RF was made a notifiable condition in 1989. It has recently been suggested that the reporting of RF cases may be incomplete, possibly because of underreporting by health care professionals and deficient administration of the disease notification system in South Africa. METHOD AND RESULTS: We assessed whether underreporting of RF cases occurs by comparing the numbers of RF cases reported per year at hospital, municipal, provincial and national levels from 1990 to 2004. There was a fall in the number of RF cases reported per year at national and provincial level over the 15 years of observation. A detailed analysis of the number of RF cases reported at hospital, municipal and provincial level for a 5-year period showed that more cases were diagnosed in one hospital (serving a smaller population) than were captured at municipal and provincial level (serving a larger population), suggesting underreporting by health care professionals. There were discrepancies in the number of cases reported at municipal, provincial and national level, suggesting poor administration of the notification system. CONCLUSION: There appears to be underreporting of RF cases by health care professionals, and poor administration of the RF notification system. Health care professionals need to be educated about the statutory requirement to notify all RF cases in South Africa. An effective national disease notification system is required.  相似文献   
95.
96.
97.
Traumatic injuries of the elbow are frequent in patients of all ages but are particularly common in young children and adolescents engaged in normal play and athletic competition. Injury may result primarily due to direct trauma or may be secondary to transmission of forces through the elbow following a fall on an outstretched hand. In middle-aged and older individuals, chronic repetitive injuries tend to predominate. In all patients, radiographs remain the initial imaging study of choice. Many patients, however, may need advanced cross-sectional imaging (i.e. MRI, CT, or ultrasound) either at presentation or during the course of their treatment and follow-up. This article reviews the imaging appearance of common acute and chronic traumatic disorders of the elbow.  相似文献   
98.
99.
100.
Both vascular surgery and endovascular interventions traumatise the arterial wall, especially the endothelium. The vessel responds with neointimal hyperplasia and/or constrictive remodelling, and this is still the limiting factor in curative interventions. Stent placement prevents constrictive remodelling but is the main trigger for in-stent restenosis. Hyperproliferation of neointimal tissue is the main response to arterial thrombosis, local inflammation or medio-intimal injury such as occurs, for example, after balloon dilatation in the region of arterial anastomoses or of a thrombectomy (Fogarty-manoeuvre). At present, research on prevention of restenosis is focused on inhibiting neointimal hyperproliferation by using drug-eluting stents, and especially sirolimus- or paclitaxel-eluting stents. In addition, further experimental research work is in progress, with the aim of esablishing new treatment regimens and solving the problem of neointimal formation, thrombosis and constrictive remodelling. These include both local and systemic pharmacological therapy, brachy- and laser therapy, and many genetic treatment options, some of which are currently the subjects of experimental studies and early-stage clinical trials. Gene therapy seems like a promising way of preventing restenosis, but has not yet been tested in clinical trials. In the near future, selective, simultaneous, and perhaps even polyphasic regulation for gene silencing of two or more genes involved in the development of restenosis could improve the long-term patency rate.  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