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   23385篇
  免费   332篇
  国内免费   14篇
教育   16639篇
科学研究   1921篇
各国文化   251篇
体育   2295篇
综合类   7篇
文化理论   212篇
信息传播   2406篇
  2021年   232篇
  2020年   359篇
  2019年   537篇
  2018年   734篇
  2017年   666篇
  2016年   666篇
  2015年   405篇
  2014年   535篇
  2013年   4255篇
  2012年   487篇
  2011年   540篇
  2010年   404篇
  2009年   436篇
  2008年   475篇
  2007年   439篇
  2006年   414篇
  2005年   360篇
  2004年   392篇
  2003年   305篇
  2002年   326篇
  2001年   460篇
  2000年   510篇
  1999年   434篇
  1998年   256篇
  1997年   248篇
  1996年   306篇
  1995年   245篇
  1994年   258篇
  1993年   221篇
  1992年   350篇
  1991年   366篇
  1990年   339篇
  1989年   365篇
  1988年   336篇
  1987年   326篇
  1986年   328篇
  1985年   371篇
  1984年   292篇
  1983年   305篇
  1982年   240篇
  1981年   246篇
  1980年   261篇
  1979年   350篇
  1978年   259篇
  1977年   239篇
  1976年   198篇
  1975年   164篇
  1974年   167篇
  1973年   164篇
  1971年   151篇
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
991.
Mick E  Biederman J  Faraone SV 《Journal of learning disabilities》2000,33(4):314; author reply 314-314; author reply 316
  相似文献   
992.
Electronic reserves present a new service option for libraries to provide needed materials during hours that the library is not open and to user groups located some distance from library collections. Possible changes to current copyright law and publishers permissions policies have delayed the development of electronic reserves in many libraries. This paper reviews the current state of electronic reserves materials in the publishing and library communities and presents the results of a survey of publishers to determine permissions policies for electronic materials. Issues of concern to both libraries and publishers are discussed.  相似文献   
993.
994.
In 1998 Thomas Jefferson University offered its first entirely online course. Librarians and library staff were integral in the development, support, evaluation, and refinement of this course. While staff members may have taken non-traditional roles in this effort, their roles generally fell within the broad guidelines of assisting University faculty with information and knowledge management. The development and support of distance course offerings will continue to be a focus at Scott Memorial Library.  相似文献   
995.
996.
This study was designed to assess the effect of performance feedback on stress reactivity after recovery from maximal exercise. Forty competitive athletes were recruited to complete a maximal exercise test. Performance feedback was manipulated after the exercise test to give four groups: (1) high performance, (2) low performance, (3) accurate feedback and (4) no exercise control. Cardiovascular reactivity was assessed during psychological stress. The results indicate that accurate feedback participants experienced lower relative reactivity to stress (lower mean arterial pressure) than their no-exercise counterparts. These results demonstrate that the stress-buffering effect of exercise extends to maximal exercise. In addition, high-performance participants experienced lower relative reactivity than low-performance participants. Thus, low-performance feedback was sufficient to remove the buffering effect of exercise. There were no differences between the high-performance and accurate feedback conditions, or between the low-performance and control conditions.  相似文献   
997.
998.
This paper explores the association between moderate levels of physical activity (PA) and health benefits in well being and symptoms such as tiredness, back pain, and constipation. Participants in the Australian Longitudinal Study on Women's Health, 14,502 young women (ages 18-23 years), 13,609 middle-age women (45-50 years), and 11,421 older women (ages 70-75 years), answered questions about vigorous and less vigorous exercise (used to determine a physical activity score), well being (SF-36), symptoms, and medical conditions. There were significant associations between the PA score and SF-36 in each cohort. Odds ratios (OR) for a range of symptoms and conditions were lower for women who reported low to moderate activity than for sedentary women, for example, for young women or for constipation = 0.76 (CI, 0.65-0.89), for middle-age women or for tiredness = 0.70 (0.63-0.78). There was no threshold of PA at which health benefits increased significantly. Although cross-sectional, the findings suggest that low-to-moderate levels of exercise are associated with a range of health benefits for women of all ages. These preliminary findings will be followed up during the longitudinal study.  相似文献   
999.
There is little research on students' engagement in physical activity in middle school physical education (PE). We observed student activity, lesson context, and teacher behavior in 430 PE lessons taught by 126 teachers in 24 schools. Variables were analyzed by mixed-model nested analyses of covariance. Boys were more active than girls overall and during skill drills, game play, and free play. Student activity varied by lesson context, with fitness activities producing the most activity. Class size was negatively associated with student activity. Daily PE contributed a weekly total of 25 min of vigorous activity and 83 min of moderate-to-vigorous activity--much less than national objectives. Results suggest that numerous opportunities exist for increasing student physical activity during middle school PE.  相似文献   
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