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   1672721篇
  免费   135056篇
  国内免费   2749篇
耳鼻咽喉   22557篇
儿科学   54493篇
妇产科学   47740篇
基础医学   237277篇
口腔科学   49903篇
临床医学   146463篇
内科学   331900篇
皮肤病学   35714篇
神经病学   136378篇
特种医学   66366篇
外国民族医学   474篇
外科学   253250篇
综合类   40052篇
现状与发展   3篇
一般理论   575篇
预防医学   129143篇
眼科学   37816篇
药学   125992篇
  3篇
中国医学   3215篇
肿瘤学   91212篇
  2018年   16973篇
  2016年   14357篇
  2015年   16975篇
  2014年   22693篇
  2013年   34320篇
  2012年   48788篇
  2011年   51199篇
  2010年   29278篇
  2009年   27436篇
  2008年   48387篇
  2007年   50807篇
  2006年   51537篇
  2005年   49967篇
  2004年   48864篇
  2003年   46534篇
  2002年   45418篇
  2001年   76893篇
  2000年   79889篇
  1999年   67189篇
  1998年   17961篇
  1997年   16501篇
  1996年   16485篇
  1995年   16184篇
  1994年   15198篇
  1993年   14339篇
  1992年   55558篇
  1991年   53897篇
  1990年   52632篇
  1989年   50917篇
  1988年   47279篇
  1987年   46610篇
  1986年   44346篇
  1985年   42922篇
  1984年   32136篇
  1983年   27627篇
  1982年   16236篇
  1981年   14511篇
  1980年   13649篇
  1979年   30505篇
  1978年   21108篇
  1977年   17802篇
  1976年   16730篇
  1975年   17602篇
  1974年   21528篇
  1973年   20698篇
  1972年   18860篇
  1971年   17784篇
  1970年   16305篇
  1969年   15282篇
  1968年   13951篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation.  相似文献   
5.
6.
7.
8.
9.
10.
Past research suggests that as many as 50% of onward human immunodeficiency virus (HIV) transmissions occur during acute and recent HIV infection. It is clearly important to develop interventions which focus on this highly infectious stage of HIV infection to prevent further transmission in the risk networks of acutely and recently infected individuals. Project Protect tries to find recently and acutely infected individuals and prevents HIV transmission in their risk networks. Participants are recruited by community health outreach workers at community-based HIV testing sites and drug users' community venues, by coupon referrals and through referrals from AIDS clinics. When a network with acute/recent infection is identified, network members are interviewed about their risky behaviors, network information is collected, and blood is drawn for HIV testing. Participants are also educated and given prevention materials (condoms, syringes, educational materials); HIV-infected participants are referred to AIDS clinics and are assisted with access to care. Community alerts about elevated risk of HIV transmission are distributed within the risk networks of recently infected. Overall, 342 people were recruited to the project and screened for acute/recent HIV infection. Only six index cases of recent infection (2.3% of all people screened) were found through primary screening at voluntary counseling and testing (VCT) sites, but six cases of recent infection were found through contact tracing of these recently infected participants (7% of network members who came to the interview). Combining screening at VCT sites and contact tracing the number of recently infected people we located as compared to VCT screening alone. No adverse events were encountered. These first results provide evidence for the theory behind the intervention, i.e., in the risk networks of recently infected people there are other people with recent HIV infection and they can be successfully located without increasing stigma for project participants.  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