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   3451782篇
  免费   247394篇
  国内免费   6132篇
耳鼻咽喉   47027篇
儿科学   112624篇
妇产科学   94009篇
基础医学   498796篇
口腔科学   98290篇
临床医学   313725篇
内科学   664394篇
皮肤病学   77038篇
神经病学   272385篇
特种医学   129171篇
外国民族医学   693篇
外科学   518345篇
综合类   76023篇
现状与发展   14篇
一般理论   1255篇
预防医学   267443篇
眼科学   82722篇
药学   254810篇
  13篇
中国医学   7545篇
肿瘤学   188986篇
  2021年   26892篇
  2019年   27780篇
  2018年   39061篇
  2017年   29478篇
  2016年   32932篇
  2015年   37186篇
  2014年   52405篇
  2013年   78201篇
  2012年   107870篇
  2011年   114339篇
  2010年   68227篇
  2009年   64002篇
  2008年   106776篇
  2007年   113779篇
  2006年   115043篇
  2005年   111030篇
  2004年   106800篇
  2003年   102381篇
  2002年   98836篇
  2001年   163010篇
  2000年   167347篇
  1999年   140351篇
  1998年   39865篇
  1997年   34854篇
  1996年   35046篇
  1995年   33249篇
  1994年   30572篇
  1993年   28583篇
  1992年   108247篇
  1991年   105207篇
  1990年   101938篇
  1989年   98363篇
  1988年   90204篇
  1987年   88290篇
  1986年   83051篇
  1985年   79483篇
  1984年   59012篇
  1983年   50284篇
  1982年   29364篇
  1979年   53685篇
  1978年   37853篇
  1977年   31789篇
  1976年   30144篇
  1975年   32054篇
  1974年   38830篇
  1973年   37182篇
  1972年   34708篇
  1971年   32632篇
  1970年   30279篇
  1969年   28630篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.  相似文献   
83.
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   
84.
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain.  相似文献   
85.
86.
87.
88.
89.
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate...  相似文献   
90.
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