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   1824419篇
  免费   131566篇
  国内免费   4114篇
耳鼻咽喉   23628篇
儿科学   59186篇
妇产科学   49507篇
基础医学   260280篇
口腔科学   53179篇
临床医学   158895篇
内科学   362113篇
皮肤病学   42198篇
神经病学   141900篇
特种医学   67213篇
外国民族医学   243篇
外科学   271839篇
综合类   39678篇
现状与发展   4篇
一般理论   553篇
预防医学   140665篇
眼科学   43702篇
药学   134024篇
  8篇
中国医学   5062篇
肿瘤学   106222篇
  2021年   15036篇
  2019年   16002篇
  2018年   23714篇
  2017年   17633篇
  2016年   19069篇
  2015年   21654篇
  2014年   29467篇
  2013年   42769篇
  2012年   60828篇
  2011年   64021篇
  2010年   37090篇
  2009年   33995篇
  2008年   58436篇
  2007年   62152篇
  2006年   62374篇
  2005年   59258篇
  2004年   56985篇
  2003年   53971篇
  2002年   51944篇
  2001年   95218篇
  2000年   97482篇
  1999年   79941篇
  1998年   20364篇
  1997年   17736篇
  1996年   17824篇
  1995年   17145篇
  1994年   15655篇
  1993年   14334篇
  1992年   59135篇
  1991年   56840篇
  1990年   54534篇
  1989年   52128篇
  1988年   47469篇
  1987年   46199篇
  1986年   43522篇
  1985年   41209篇
  1984年   30203篇
  1983年   25669篇
  1982年   14310篇
  1979年   26569篇
  1978年   18264篇
  1977年   15577篇
  1976年   14497篇
  1975年   15320篇
  1974年   18609篇
  1973年   17936篇
  1972年   16639篇
  1971年   15405篇
  1970年   14318篇
  1969年   13455篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
12.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  相似文献   
13.
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to...  相似文献   
14.
15.
16.
17.
18.
19.
Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria.  相似文献   
20.
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