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   2295771篇
  免费   171512篇
  国内免费   3351篇
耳鼻咽喉   32136篇
儿科学   77685篇
妇产科学   63486篇
基础医学   333712篇
口腔科学   63161篇
临床医学   208466篇
内科学   450322篇
皮肤病学   49743篇
神经病学   182283篇
特种医学   88361篇
外国民族医学   898篇
外科学   337841篇
综合类   49110篇
现状与发展   4篇
一般理论   890篇
预防医学   183419篇
眼科学   51801篇
药学   169671篇
  8篇
中国医学   4110篇
肿瘤学   123527篇
  2018年   23994篇
  2017年   18180篇
  2016年   19945篇
  2015年   22853篇
  2014年   31589篇
  2013年   48497篇
  2012年   66421篇
  2011年   70764篇
  2010年   41590篇
  2009年   39870篇
  2008年   67143篇
  2007年   71973篇
  2006年   71810篇
  2005年   70177篇
  2004年   68099篇
  2003年   65549篇
  2002年   64042篇
  2001年   104988篇
  2000年   108167篇
  1999年   91838篇
  1998年   25812篇
  1997年   23281篇
  1996年   23913篇
  1995年   22597篇
  1994年   21265篇
  1993年   19797篇
  1992年   73291篇
  1991年   71905篇
  1990年   69853篇
  1989年   67253篇
  1988年   62177篇
  1987年   61202篇
  1986年   57659篇
  1985年   55035篇
  1984年   41695篇
  1983年   35613篇
  1982年   20989篇
  1981年   19159篇
  1979年   38359篇
  1978年   27589篇
  1977年   23167篇
  1976年   21683篇
  1975年   23316篇
  1974年   27801篇
  1973年   27205篇
  1972年   25397篇
  1971年   23442篇
  1970年   22039篇
  1969年   20519篇
  1968年   18959篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Haemophilia is a common cause of genetically inherited bleeding disorders. Pseudotumours occur in 1–2 % of persons with severe forms of haemophilia. These are a result of repeated haemorrhage into soft tissues, subperiosteum or a site of bone fracture with inadequate resorption of the extravasated blood. There are a number of therapeutic alternatives for this dangerous condition: surgical removal, percutaneous management, irradiation, embolization etc. In this case report, we describe the natural history, clinical course and successful surgical management of a patient with haemophilia who presented with a massive pseudotumour. We also briefly review the relevant literature on the various therapeutic modalities that have been implemented in the management of this rare complication. Though surgeons may be averse to operate on haemophiliacs, primary surgical management as done in our case may prove to be the definitive treatment option for such patients.  相似文献   
42.
43.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered.  相似文献   
44.
45.
46.
47.
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   
48.
49.
50.
AimsThe aims were to 1) develop the pharmacokinetics model to describe and predict observed tanezumab concentrations over time, 2) test possible covariate parameter relationships that could influence clearance and distribution and 3) assess the impact of fixed dosing vs. a dosing regimen adjusted by body weight.MethodsIndividual concentration–time data were determined from 1608 patients in four phase 3 studies conducted to assess efficacy and safety of intravenous tanezumab. Patients received two or three intravenous doses (2.5, 5 or 10 mg) every 8 weeks. Blood samples for assessment of tanezumab PK were collected at baseline, 1 h post‐dose and at weeks 4, 8, 16 and 24 (or early termination) in all studies. Blood samples were collected at week 32 in two studies. Plasma samples were analyzed using a sensitive, specific, validated enzyme‐linked immunosorbent assay.ResultsA two compartment model with parallel linear and non‐linear elimination processes adequately described the data. Population estimates for clearance (CL), central volume (V 1), peripheral volume (V 2), inter‐compartmental clearance, maximum elimination capacity (VM) and concentration at half‐maximum elimination capacity were 0.135 l day–1, 2.71 l, 1.98 l, 0.371 l day–1, 8.03 μg day–1 and 27.7 ng ml–1, respectively. Inter‐individual variability (IIV) was included on CL, V 1, V 2 and VM. A mixture model accounted for the distribution of residual error. While gender, dose and creatinine clearance were significant covariates, only body weight as a covariate of CL, V 1 and V 2 significantly reduced IIV.ConclusionsThe small increase in variability associated with fixed dosing is consistent with other monoclonal antibodies and does not change risk : benefit.  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