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   1708699篇
  免费   127741篇
  国内免费   4326篇
耳鼻咽喉   21878篇
儿科学   55892篇
妇产科学   46606篇
基础医学   243277篇
口腔科学   49079篇
临床医学   153228篇
内科学   336852篇
皮肤病学   38842篇
神经病学   132120篇
特种医学   64262篇
外国民族医学   245篇
外科学   259318篇
综合类   40343篇
现状与发展   7篇
一般理论   536篇
预防医学   125163篇
眼科学   40708篇
药学   124952篇
  13篇
中国医学   5026篇
肿瘤学   102419篇
  2021年   13424篇
  2019年   13965篇
  2018年   20466篇
  2017年   15661篇
  2016年   17036篇
  2015年   19545篇
  2014年   26912篇
  2013年   38765篇
  2012年   53952篇
  2011年   56763篇
  2010年   33563篇
  2009年   31332篇
  2008年   52473篇
  2007年   55755篇
  2006年   56246篇
  2005年   53504篇
  2004年   51535篇
  2003年   48803篇
  2002年   47003篇
  2001年   92069篇
  2000年   93901篇
  1999年   77248篇
  1998年   19872篇
  1997年   17423篇
  1996年   17516篇
  1995年   16832篇
  1994年   15376篇
  1993年   14134篇
  1992年   57485篇
  1991年   55372篇
  1990年   53056篇
  1989年   50825篇
  1988年   46200篇
  1987年   45007篇
  1986年   42287篇
  1985年   40028篇
  1984年   29377篇
  1983年   24933篇
  1982年   13930篇
  1979年   25555篇
  1978年   17599篇
  1977年   14916篇
  1976年   13882篇
  1975年   14581篇
  1974年   17643篇
  1973年   16956篇
  1972年   15681篇
  1971年   14461篇
  1970年   13434篇
  1969年   12520篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
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   
12.
13.
14.
15.
16.
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   
17.
18.
19.
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