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   44178篇
  免费   1727篇
  国内免费   31篇
  45936篇
  2020年   490篇
  2019年   648篇
  2018年   884篇
  2017年   928篇
  2016年   927篇
  2015年   674篇
  2014年   796篇
  2013年   3840篇
  2012年   1395篇
  2011年   1552篇
  2010年   982篇
  2009年   1015篇
  2008年   1387篇
  2007年   1319篇
  2006年   1270篇
  2005年   1109篇
  2004年   1031篇
  2003年   1088篇
  2002年   1030篇
  2001年   1423篇
  2000年   1375篇
  1999年   1045篇
  1998年   543篇
  1997年   488篇
  1996年   469篇
  1995年   449篇
  1994年   441篇
  1993年   437篇
  1992年   847篇
  1991年   836篇
  1990年   779篇
  1989年   717篇
  1988年   663篇
  1987年   682篇
  1986年   660篇
  1985年   756篇
  1984年   622篇
  1983年   498篇
  1982年   413篇
  1981年   424篇
  1979年   556篇
  1978年   450篇
  1977年   419篇
  1976年   399篇
  1975年   501篇
  1974年   517篇
  1973年   552篇
  1972年   438篇
  1968年   403篇
  1966年   410篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
We investigated eye‐movements during preschool children's pictorial recall of seen objects. Thirteen 3‐ to 4‐year‐old children completed a perceptual encoding and a pictorial recall task. First, they were exposed to 16 pictorial objects, which were positioned in one of four distinct areas on the computer screen. Subsequently, they had to recall these pictorial objects from memory in order to respond to specific questions about visual details. We found that children spent more time fixating the areas in which the pictorial objects were previously displayed. We conclude that as early as age 3–4 years old, children show specific eye‐movements when they recall pictorial contents of previously seen objects.  相似文献   
22.
23.
24.
25.
26.
27.
Although perceived health risk plays a prominent role in theories of health behavior, its empirical role in risk taking is less clear. In Study 1 (N = 129), 2 measures of drivers' risk-taking behavior were found to be unrelated to self-estimates of accident concern but to be related to self-ratings of driving skill and the perceived thrill of driving. In Study 2 (N = 405), out of a wide range of potential influences, accident concern had the weakest relationship with risk taking. The authors concluded that although health risk is a key feature in many theories of health behavior and a central focus for researchers and policy makers, it may not be such a prominent factor for those actually taking the risk.  相似文献   
28.
The authors used recursive partitioning methods to identify combinations of baseline characteristics that predict 2-year physical activity success in each of 3 physical activity interventions delivered in the multisite Activity Counseling Trial. The sample consisted of 874 initially sedentary primary care patients, ages 35-75 years, who were at risk for cardiovascular disease. Predictors of 2-year success were specific to each intervention and represented a range of domains, including physiological, demographic, psychosocial, health-related, and environmental variables. The results indicate how specific patient subgroups (e.g., obese, unfit individuals; high-income individuals in stable health) may respond differently to varying levels and amounts of professional assistance and support. The methods used provide a practical first step toward identifying clinically meaningful patient subgroups for further systematic investigation.  相似文献   
29.
30.
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