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   1731436篇
  免费   129956篇
  国内免费   6705篇
耳鼻咽喉   22061篇
儿科学   56216篇
妇产科学   46691篇
基础医学   246014篇
口腔科学   49377篇
临床医学   156613篇
内科学   339338篇
皮肤病学   39028篇
神经病学   133462篇
特种医学   65144篇
外国民族医学   259篇
外科学   261478篇
综合类   45456篇
现状与发展   9篇
一般理论   537篇
预防医学   126519篇
眼科学   41299篇
药学   127705篇
  38篇
中国医学   6311篇
肿瘤学   104542篇
  2021年   14866篇
  2019年   14999篇
  2018年   21430篇
  2017年   16503篇
  2016年   17824篇
  2015年   20762篇
  2014年   28459篇
  2013年   39947篇
  2012年   55718篇
  2011年   58639篇
  2010年   34708篇
  2009年   32261篇
  2008年   53613篇
  2007年   56925篇
  2006年   57272篇
  2005年   54611篇
  2004年   52081篇
  2003年   49481篇
  2002年   47487篇
  2001年   92591篇
  2000年   94473篇
  1999年   77975篇
  1998年   20312篇
  1997年   17926篇
  1996年   17888篇
  1995年   17199篇
  1994年   15679篇
  1993年   14350篇
  1992年   57677篇
  1991年   55535篇
  1990年   53189篇
  1989年   50930篇
  1988年   46296篇
  1987年   45080篇
  1986年   42354篇
  1985年   40066篇
  1984年   29400篇
  1983年   24962篇
  1982年   13939篇
  1979年   25563篇
  1978年   17587篇
  1977年   14919篇
  1976年   13881篇
  1975年   14570篇
  1974年   17642篇
  1973年   16955篇
  1972年   15676篇
  1971年   14456篇
  1970年   13433篇
  1969年   12522篇
排序方式: 共有10000条查询结果,搜索用时 2 毫秒
11.
12.
“三全育人”是高校思政教育工作的关键一环,也是中医药高校推动思政教育的重要内容。以“三全育人”为视角对北京中医药大学思想政治教育举措“杏林成长导师”计划路径、内容深入分析,运用统计分析和文献研究方法,剖析该计划对中医学专业大学生的学业、思想和实践等多个层面的现实成效,从而为“三全育人”理念在中医药院校制度建构中的应用提供新的视角与方法。  相似文献   
13.
14.
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
15.
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   
16.
The research and development of penicillin started with difficulty before 1949 and achieved certain results. In 1951, after the founding of the People's Republic of China, Zhang Weishen, as the only Chinese scientist who had been trained and worked in a penicillin research and development center in the United States for many years, overcame many difficulties and returned to China. In 1953, with the efforts of Zhang Weishen and his colleagues, China realized the industrialized production of penicillin, alleviating the urgent needs of the masses. Antibiotics has also become the first discipline to achieve major scientific and technological achievements after the founding of the New China. In the mid-1950s, the technical breakthrough in the localization of lactose substitutes marked the localization of the raw materials of the penicillin-producing culture medium, which paved the way for the industrialized production of penicillin with Chinese characteristics. Antibiotics have become one of the most widely used and affordable drugs for hundreds of millions of patients in China, and China has since ended the humiliating history of the “Sick Man of East Asia".  相似文献   
17.
18.
19.
20.
Clinical and Experimental Medicine - Recently, the use of novel targeted drugs significantly improved the overall response rate (ORR) and survival of patients with relapsed/refractory chronic...  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