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   4891612篇
  免费   394813篇
  国内免费   17886篇
耳鼻咽喉   69420篇
儿科学   154574篇
妇产科学   130313篇
基础医学   735892篇
口腔科学   138212篇
临床医学   454126篇
内科学   887893篇
皮肤病学   113982篇
神经病学   413721篇
特种医学   192399篇
外国民族医学   1154篇
外科学   730726篇
综合类   143368篇
现状与发展   23篇
一般理论   2811篇
预防医学   422000篇
眼科学   115847篇
药学   347444篇
  29篇
中国医学   13201篇
肿瘤学   237176篇
  2021年   56750篇
  2019年   59376篇
  2018年   75791篇
  2017年   57973篇
  2016年   64412篇
  2015年   77151篇
  2014年   112103篇
  2013年   178069篇
  2012年   139757篇
  2011年   146961篇
  2010年   130442篇
  2009年   130811篇
  2008年   132574篇
  2007年   141924篇
  2006年   149790篇
  2005年   144474篇
  2004年   144273篇
  2003年   134120篇
  2002年   124064篇
  2001年   182810篇
  2000年   180151篇
  1999年   163506篇
  1998年   75165篇
  1997年   70478篇
  1996年   68224篇
  1995年   64145篇
  1994年   58233篇
  1993年   53957篇
  1992年   123141篇
  1991年   118680篇
  1990年   113819篇
  1989年   110251篇
  1988年   102428篇
  1987年   100661篇
  1986年   95806篇
  1985年   93491篇
  1984年   76888篇
  1983年   67919篇
  1982年   51850篇
  1981年   48087篇
  1980年   45215篇
  1979年   68785篇
  1978年   54065篇
  1977年   47148篇
  1976年   44366篇
  1975年   44252篇
  1974年   50711篇
  1973年   48890篇
  1972年   45822篇
  1971年   42349篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
Liver-related death in human immunodeficiency virus (HIV)-infected individuals is about 10 times higher compared with the general population, and the prevalence of significant liver fibrosis in those with HIV approaches 15%. The present study aimed to assess risk factors for development of hepatic fibrosis in HIV patients receiving a modern combination anti-retroviral therapy (cART).This cross-sectional prospective study included 432 HIV patients, of which 68 (16%) patients were anti-hepatitis C virus (HCV) positive and 23 (5%) were HBsAg positive.Health trajectory including clinical characteristics and liver fibrosis stage assessed by transient elastography were collected at inclusion. Liver stiffness values >7.1 kPa were considered as significant fibrosis, while values >12.5 kPa were defined as severe fibrosis. Logistic regression and Cox regression uni- and multivariate analyses were performed to identify independent factors associated with liver fibrosis.Significant liver fibrosis was detected in 10% of HIV mono-infected, in 37% of HCV co-infected patients, and in 18% of hepatitis B virus co-infected patients. The presence of diabetes mellitus (odds ratio [OR] = 4.6) and FIB4 score (OR = 2.4) were independently associated with presence of significant fibrosis in the whole cohort. Similarly, diabetes mellitus (OR = 5.4), adiposity (OR = 4.6), and the FIB4 score (OR = 3.3) were independently associated with significant fibrosis in HIV mono-infected patients. Importantly, cumulative cART duration protected, whereas persistent HIV viral replication promoted the development of significant liver fibrosis along the duration of HIV infection.Our findings strongly indicate that besides known risk factors like metabolic disorders, HIV may also have a direct effect on fibrogenesis. Successful cART leading to complete suppression of HIV replication might protect from development of liver fibrosis.  相似文献   
995.
996.
997.
As countries implement Article 11 of the World Health Organization (WHO) Framework Convention on Tobacco Control, graphic warning labels that use images of people and their body parts to illustrate the consequences of smoking are being added to cigarette packs. According to exemplification theory, these case examples—exemplars—can shape perceptions about risk and may resonate differently among demographic subpopulations. Drawing on data from eight focus groups (N = 63) with smokers and nonsmokers from vulnerable populations, this qualitative study explores whether people considered exemplars in their reactions to and evaluations of U.S. graphic health warning labels initially proposed by the Food and Drug Administration. Participants made reference to prior and concurrent mass media messages and exemplars during the focus groups and used demographic cues in making sense of the images on the warning labels. Participants were particularly sensitive to age of the exemplars and how it might affect label effectiveness and beliefs about smoking. Race and socioeconomic status also were salient for some participants. We recommend that exemplars and exemplification be considered when selecting and evaluating graphic health warnings for tobacco labels and associated media campaigns.  相似文献   
998.
999.
1000.
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