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   9590篇
  免费   692篇
  国内免费   17篇
耳鼻咽喉   61篇
儿科学   345篇
妇产科学   325篇
基础医学   1121篇
口腔科学   253篇
临床医学   1566篇
内科学   1659篇
皮肤病学   162篇
神经病学   836篇
特种医学   194篇
外科学   961篇
综合类   134篇
一般理论   9篇
预防医学   1361篇
眼科学   248篇
药学   510篇
  1篇
中国医学   6篇
肿瘤学   547篇
  2023年   41篇
  2022年   68篇
  2021年   176篇
  2020年   98篇
  2019年   189篇
  2018年   200篇
  2017年   182篇
  2016年   170篇
  2015年   180篇
  2014年   257篇
  2013年   405篇
  2012年   584篇
  2011年   687篇
  2010年   341篇
  2009年   297篇
  2008年   585篇
  2007年   613篇
  2006年   600篇
  2005年   573篇
  2004年   540篇
  2003年   516篇
  2002年   509篇
  2001年   114篇
  2000年   127篇
  1999年   134篇
  1998年   100篇
  1997年   100篇
  1996年   93篇
  1995年   83篇
  1994年   66篇
  1993年   67篇
  1992年   103篇
  1991年   60篇
  1990年   82篇
  1989年   89篇
  1988年   77篇
  1987年   79篇
  1986年   75篇
  1985年   81篇
  1984年   73篇
  1983年   71篇
  1982年   58篇
  1981年   46篇
  1980年   43篇
  1979年   65篇
  1978年   66篇
  1977年   50篇
  1976年   48篇
  1973年   43篇
  1969年   43篇
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
1.
2.
3.
Objective: Several biologic therapies are available for the treatment of mild-to-moderate Crohn’s disease (CD). This network meta-analysis (NMA) aimed to assess the comparative efficacy of ustekinumab, adalimumab, vedolizumab and infliximab in the maintenance of clinical response and remission after 1?year of treatment.

Methods: A systematic literature search was performed to identify relevant randomized controlled trials (RCTs). Key outcomes of interest were clinical response (CD activity index [CDAI] reduction of 100 points; CDAI-100) and remission (CDAI score under 150 points; CDAI < 150). A treatment sequence Bayesian NMA was conducted to account for the re-randomization of patients based on different clinical definitions, the lack of similarity of the common comparator for each trial and the full treatment pathway from the induction phase onwards.

Results: Thirteen RCTs were identified. Ustekinumab 90?mg q8w was associated with statistically significant improvement in clinical response relative to placebo and vedolizumab 300?mg. For clinical remission, ustekinumab 90?mg q8w was associated with statistically significant improvement relative to placebo and vedolizumab 300?mg q8w. Findings from sub-population analyses had similar results but were not statistically significant.

Conclusions: The NMA suggest that ustekinumab is associated with the highest likelihood of reaching response or remission at 1?year compared with placebo, adalimumab and vedolizumab. Results should be interpreted with caution because this is a novel methodology; however, the treatment sequence analysis may be the most methodologically sound analysis to derive estimates of comparative efficacy in CD in the absence of head-to-head evidence.  相似文献   

4.
5.
6.
7.
8.
9.
10.
Extrahepatic portal vein thrombosis (EHPVT) may occur in children or adults and usually comes to clinical attention due to complications of portal hypertension such as variceal hemorrhage. A variety of standard surgical techniques exist to manage these patients, but when these fail surgical options are limited. We describe two novel portosystemic shunts that utilize the gonadal vein as an autologous conduit. Four patients were evaluated for EHPVT with variceal bleeding. None of the patients were candidates for a standard splenorenal shunt due to prior surgical procedures. The first patient underwent a left mesogonadal shunt and the remaining 3 patients underwent a right mesogonadal shunt. Postoperative ultrasound or computed tomography (CT) scan confirmed early patency of the shunt in each patient. There have been no further episodes of variceal hemorrhage with follow-up of 3.5 years in the child who underwent the left mesogonadal shunt, and 17, 19, and 20 months in the patients who underwent the right mesogonadal shunt. Three of the 4 shunts remain patent. One shunt thrombosis occurred in a patient homozygous for the Factor V Leiden mutation despite anticoagulation with coumadin. This is the first report of the successful use of the gonadal vein as an in situ conduit for constructing a portosystemic shunt. In conclusion, the right and left mesogonadal shunts may be useful as salvage operations for patients with EHPVT who have failed standard surgical shunt procedures.  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