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   1282369篇
  免费   100260篇
  国内免费   2034篇
耳鼻咽喉   18469篇
儿科学   44431篇
妇产科学   35130篇
基础医学   183023篇
口腔科学   33862篇
临床医学   111784篇
内科学   259347篇
皮肤病学   28155篇
神经病学   100895篇
特种医学   51410篇
外国民族医学   660篇
外科学   197380篇
综合类   27089篇
现状与发展   1篇
一般理论   381篇
预防医学   95943篇
眼科学   28037篇
药学   95296篇
  2篇
中国医学   2439篇
肿瘤学   70929篇
  2018年   13264篇
  2017年   10110篇
  2016年   11047篇
  2015年   12544篇
  2014年   17412篇
  2013年   26458篇
  2012年   36430篇
  2011年   38490篇
  2010年   23039篇
  2009年   22043篇
  2008年   37044篇
  2007年   39656篇
  2006年   39898篇
  2005年   38835篇
  2004年   37954篇
  2003年   36794篇
  2002年   36106篇
  2001年   64060篇
  2000年   66547篇
  1999年   56464篇
  1998年   15208篇
  1997年   13813篇
  1996年   14257篇
  1995年   13498篇
  1994年   12806篇
  1993年   11819篇
  1992年   44586篇
  1991年   43503篇
  1990年   42252篇
  1989年   40154篇
  1988年   36921篇
  1987年   36264篇
  1986年   33642篇
  1985年   32305篇
  1984年   24164篇
  1983年   20297篇
  1982年   11748篇
  1981年   10714篇
  1980年   9525篇
  1979年   21356篇
  1978年   14828篇
  1977年   12543篇
  1976年   11701篇
  1975年   12631篇
  1974年   14672篇
  1973年   14122篇
  1972年   12955篇
  1971年   11739篇
  1970年   11063篇
  1969年   10038篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
12.
13.
14.
15.
BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
16.
Background: Traumatic brain injury (TBI) results in verbal recall deficits and impaired processing of emotion encoded in facial appearance, prosody and the linguistic content of messages. Emotion facilitates memory (emotional memory advantage) for non-brain injured (NBI) individuals but the impact of emotion on verbal recall for linguistically encoded stimuli in TBI has not been explored.

Aims: The purpose of this study was to determine the effects of stimulus emotional content on verbal recall of words and paragraphs in TBI compared to NBI individuals.

Methods and procedures: Six 10-item lists, each with five emotional and five neutral words, and six paragraphs (three emotional, three neutral) were counterbalanced and presented in random order to 20 individuals with TBI and 44 NBI. The number of words from lists and the number of content units from paragraphs were compared for the two groups.

Outcomes and results: The NBI participants recalled more words from the lists and content units from the paragraphs than the individuals with TBI. Both groups recalled significantly more emotional than neutral words. NBI but not TBI participants had significantly greater recall for information in paragraphs with emotional content.

Conclusions: Participants with TBI showed impaired recall of words and paragraph content. Emotion facilitated word and paragraph content recall for neurotypical individuals but emotional memory advantage was limited to words for the TBI participants.  相似文献   

17.
18.
19.
20.
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