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   98658篇
  免费   3887篇
  国内免费   57篇
  2020年   1076篇
  2019年   1293篇
  2018年   1819篇
  2017年   1841篇
  2016年   2026篇
  2015年   1381篇
  2014年   1680篇
  2013年   8214篇
  2012年   3017篇
  2011年   3212篇
  2010年   1909篇
  2009年   1963篇
  2008年   2877篇
  2007年   2776篇
  2006年   2477篇
  2005年   2233篇
  2004年   2210篇
  2003年   2042篇
  2002年   2104篇
  2001年   2952篇
  2000年   2883篇
  1999年   2188篇
  1998年   1151篇
  1997年   1031篇
  1996年   939篇
  1995年   944篇
  1992年   1826篇
  1991年   1740篇
  1990年   1716篇
  1989年   1603篇
  1988年   1537篇
  1987年   1485篇
  1986年   1523篇
  1985年   1637篇
  1984年   1348篇
  1983年   1208篇
  1982年   950篇
  1979年   1382篇
  1978年   1036篇
  1976年   939篇
  1975年   1189篇
  1974年   1376篇
  1973年   1368篇
  1972年   1203篇
  1971年   1089篇
  1970年   998篇
  1969年   1023篇
  1968年   1297篇
  1967年   1209篇
  1966年   1108篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
11.
12.
Ten untreated patients with recently diagnosed Parkinson's disease (PD), 9 treated patients with more advanced pathology, and 17 matched normal controls were investigated with three reaction tasks with increasing cognitive load but identical motor requirements: simple reaction, choice reaction with indicative stimuli, and choice reaction with ambiguous stimuli. Times required until a home key was released (= reaction time) and from then until a response key was pressed (= movement time) were recorded. Estimates of pure decision time (overall response time minus movement time in a simple reaction time task) revealed a difference between advanced and early PD patients. Advanced PD patients showed an overall slowing of decision time in the reaction time tasks, but the effect of the cognitive load of the tasks on the decision time was comparable to a control group. The untreated early PD patients performed quite normally in the more simple decision tasks but showed a disproportionate slowing of decision time in tasks with higher cognitive load.  相似文献   
13.
14.
15.
16.
17.
18.
19.
The purpose of this study is to compare field investigative interviews of children (FIIC) with three different legal outcomes in child sexual abuse cases: (i) insufficient evidence to proceed (IEP); (ii) convictions; or (iii) acquittals by the court. One hundred FIIC were divided into one of the three outcome possibilities. Amongst the female interviewees older than 10 years, there were no cases of acquittals and the convicted cases were over-represented. The children's response to open questions was found to be the main difference between the three FIIC outcomes. The responses to these open questions were 1.9 and 2.3 times longer in the convicted cases compared to acquittals and IEP. Possible explanations for the result are discussed. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
20.
We investigated motivational and cognitive processes of behavior change with respect to mammography screening. One hundred forty-two women (ages 40 and older) recruited from three worksites answered a 41-item questionnaire consisting of statements based on constructs from the transtheoretical model of behavior change. Principal-components analysis identified two factors: a six-item component representing positive perceptions of mammography (Pros) and a six-item component representing avoidance of mammography (Cons). Analysis of variance showed that Pros, Cons, and a derived Decisional Balance measure (Pros minus Cons) were associated with stage of mammography adoption. Results are consistent with applications of the model to smoking cessation. The model is also discussed as it relates to other theories of behavior change and as a general strategy for analyzing perceptual data pertinent to health-related actions and intentions for behavioral change.  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