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   1703531篇
  免费   127205篇
  国内免费   3788篇
耳鼻咽喉   21783篇
儿科学   56037篇
妇产科学   46562篇
基础医学   242661篇
口腔科学   48841篇
临床医学   153238篇
内科学   335106篇
皮肤病学   38772篇
神经病学   132176篇
特种医学   64203篇
外国民族医学   242篇
外科学   258233篇
综合类   39052篇
现状与发展   4篇
一般理论   543篇
预防医学   125867篇
眼科学   40254篇
药学   124319篇
  7篇
中国医学   4481篇
肿瘤学   102143篇
  2021年   12954篇
  2019年   13730篇
  2018年   20170篇
  2017年   15430篇
  2016年   16782篇
  2015年   19185篇
  2014年   26561篇
  2013年   38485篇
  2012年   53512篇
  2011年   56239篇
  2010年   33253篇
  2009年   31118篇
  2008年   52265篇
  2007年   55615篇
  2006年   56031篇
  2005年   53395篇
  2004年   51579篇
  2003年   48929篇
  2002年   47087篇
  2001年   91931篇
  2000年   93725篇
  1999年   77109篇
  1998年   19871篇
  1997年   17397篇
  1996年   17506篇
  1995年   16820篇
  1994年   15378篇
  1993年   14179篇
  1992年   57462篇
  1991年   55355篇
  1990年   53044篇
  1989年   50815篇
  1988年   46191篇
  1987年   45004篇
  1986年   42302篇
  1985年   40080篇
  1984年   29439篇
  1983年   24974篇
  1982年   13957篇
  1979年   25577篇
  1978年   17614篇
  1977年   14945篇
  1976年   13914篇
  1975年   14599篇
  1974年   17657篇
  1973年   16971篇
  1972年   15702篇
  1971年   14474篇
  1970年   13446篇
  1969年   12537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