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   1451313篇
  免费   110284篇
  国内免费   2245篇
耳鼻咽喉   18484篇
儿科学   45860篇
妇产科学   38934篇
基础医学   212431篇
口腔科学   38947篇
临床医学   138355篇
内科学   286671篇
皮肤病学   29876篇
神经病学   120393篇
特种医学   52870篇
外国民族医学   278篇
外科学   207718篇
综合类   28802篇
现状与发展   5篇
一般理论   849篇
预防医学   122625篇
眼科学   32229篇
药学   105130篇
  42篇
中国医学   2364篇
肿瘤学   80979篇
  2021年   12730篇
  2019年   12924篇
  2018年   17455篇
  2017年   13731篇
  2016年   14749篇
  2015年   16994篇
  2014年   23732篇
  2013年   35703篇
  2012年   48679篇
  2011年   52178篇
  2010年   30348篇
  2009年   28961篇
  2008年   49318篇
  2007年   52620篇
  2006年   51929篇
  2005年   51377篇
  2004年   49336篇
  2003年   46999篇
  2002年   45492篇
  2001年   57879篇
  2000年   58410篇
  1999年   50018篇
  1998年   16004篇
  1997年   14559篇
  1996年   14838篇
  1995年   13802篇
  1994年   12830篇
  1993年   11972篇
  1992年   39392篇
  1991年   38817篇
  1990年   37435篇
  1989年   36185篇
  1988年   33642篇
  1987年   33003篇
  1986年   31451篇
  1985年   29780篇
  1984年   23284篇
  1983年   20479篇
  1982年   12961篇
  1979年   21681篇
  1978年   16247篇
  1977年   13619篇
  1976年   12572篇
  1975年   13430篇
  1974年   16211篇
  1973年   15902篇
  1972年   14902篇
  1971年   13879篇
  1970年   13091篇
  1969年   12292篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Background: Excessive drinking is commonplace at UK Universities. Individuals may misperceive how much they drink compared to others and are less likely to think that they will suffer adverse consequences. Young people often distance themselves and their friends from ‘problem drinkers’. Objectives: The aim of the study was to explore how student drinkers compared their own drinking behaviors to the drinking behaviors of others. Methods: An online survey was completed by 416 students aged 18–30 (68.5% female). They were asked ‘how do you think your drinking compares with other people like you?' and ‘how do you think your behavior when you drink compares with other people like you?’ Answers were subjected to thematic analysis. Results: The first main theme was about ‘identification as a ‘good’ drinker’. Participants suggested their own behavior when drinking was similar to their sober behavior. Further, they viewed themselves as more able to maintain a balance between staying in control and having fun while drinking. The second main theme was about ‘distancing from being a ‘bad’ drinker. Participants distanced themselves from negative prototypical drinkers, such compulsive or anti-social drinkers. They also attributed their own drinking behaviors to situational factors, but described other people as intentionally violent or aggressive. Conclusions/Importance: These findings may explain the failure of some health messages to change drinking behaviors. If drinkers perceive that their behavior when they drink is better than other people's then they may discount intervention messages. Targeting these biases could be incorporated into future interventions.  相似文献   
96.
Pharmaceuticals are ubiquitous in the natural environment with concentrations expected to rise as human population increases. Environmental risk assessments are available for a small portion of pharmaceuticals in use, raising concerns over the potential risks posed by other drugs that have little or no data. With >1900 active pharmaceutical ingredients in use, it would be a major task to test all of the compounds with little or no data. Desk-based prioritization studies provide a potential solution by identifying those substances that are likely to pose the greatest risk to the environment and which, therefore, need to be considered a priority for further study. The aim of this review was to (1) provide an overview of different prioritization exercises performed for pharmaceuticals in the environment and the results obtained; and (2) propose a new holistic risk-based prioritization framework for drugs in the environment. The suggested models to underpin this framework are discussed in terms of validity and applicability. The availability of data required to run the models was assessed and data gaps identified. The implementation of this framework may harmonize pharmaceutical prioritization efforts and ensure that, in the future, experimental resources are focused on molecules, endpoints, and environmental compartments that are biologically relevant.  相似文献   
97.
98.
99.
100.
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