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   23794篇
  免费   350篇
  国内免费   14篇
教育   16969篇
科学研究   1925篇
各国文化   256篇
体育   2324篇
综合类   7篇
文化理论   215篇
信息传播   2462篇
  2021年   241篇
  2020年   374篇
  2019年   549篇
  2018年   741篇
  2017年   695篇
  2016年   681篇
  2015年   421篇
  2014年   549篇
  2013年   4301篇
  2012年   503篇
  2011年   551篇
  2010年   411篇
  2009年   443篇
  2008年   485篇
  2007年   451篇
  2006年   421篇
  2005年   365篇
  2004年   396篇
  2003年   308篇
  2002年   334篇
  2001年   467篇
  2000年   514篇
  1999年   438篇
  1998年   257篇
  1997年   251篇
  1996年   309篇
  1995年   245篇
  1994年   262篇
  1993年   225篇
  1992年   352篇
  1991年   366篇
  1990年   343篇
  1989年   366篇
  1988年   336篇
  1987年   326篇
  1986年   325篇
  1985年   372篇
  1984年   293篇
  1983年   303篇
  1982年   239篇
  1981年   246篇
  1980年   259篇
  1979年   349篇
  1978年   258篇
  1977年   238篇
  1976年   199篇
  1975年   181篇
  1974年   183篇
  1973年   176篇
  1971年   174篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
The aim of the present study was to assess the influence of self-efficacy and past behaviour on young people's physical activity intentions using an augmented version of Ajzen's Theory of Planned Behaviour. We hypothesized that self-efficacy would exhibit discriminant validity with perceived behavioural control and explain unique variance in young people's intentions to participate in physical activity. We also expected that past physical activity behaviour would attenuate the influence of attitude, subjective norms, perceived behavioural control and self-efficacy on intention. The sample comprised 1,152 young people aged 13.5 +/- 0.6 years (mean +/- s) who completed inventories assessing their physical activity intentions, attitudes, subjective norms, perceived behavioural control, self-efficacy and past physical activity behaviour. A confirmatory factor analysis demonstrated that the constructs of the Theory of Planned Behaviour achieved discriminant validity. Furthermore, the measures of attitudes, subjective norms, perceived behavioural control and self-efficacy were significantly related to their respective belief-based measures, supporting the concurrent validity of the measures of the Theory of Planned Behaviour. A non-standard structural equation model demonstrated that attitude and self-efficacy were strong predictors of physical activity intention, but perceived behavioural control and subjective norms were not. Self-efficacy attenuated the influence of attitudes and perceived behavioural control on intention. Past behaviour predicted intention directly and indirectly through self-efficacy and attitude. The present findings demonstrate that young people with positive attitudes and high self-efficacy are more likely to form intentions to participate in physical activity. Furthermore, controlling for past physical activity behaviour revealed that the unique effects of self-efficacy and attitudes on young people's physical activity intentions were unaltered.  相似文献   
992.
Three soccer header types (shooting, clearing and passing) and two heading approaches (standing and jumping) were manipulated to quantify impact forces and neck muscle activity in elite female soccer players. The 15 participants were Division I intercollegiate soccer players. Impact forces were measured by a 15-sensor pressure array secured on the forehead. The electromyographic (EMG) activity of the left and right sternocleidomastoid and trapezius muscles was recorded using surface electrodes. Maximum impact forces and impulses as well as the EMG data were analysed with separate repeated-measures analyses of variance. Impact forces and impulses did not differ among the header types or approaches. Higher values were found for jumping versus standing headers in the mean normalized EMG for the right sternocleidomastoid. In addition, the integrated EMG was greater for the right sternocleidomastoid and right and left trapezius (P < 0.05). The sternocleidomastoid became active earlier than the trapezius and showed greater activity before ball contact. The trapezius became active just before ball contact and showed greater activity after ball contact. The increased muscle activity observed in the neck during the jumping approach appears to stabilize the connection between the head and body, thereby increasing the stability of the head-neck complex.  相似文献   
993.
Contemporary aspects of research methods in sport and exercise psychology are discussed in this wide-ranging review. After an introduction centred on trends in sport and exercise psychology methods, the review is organized around the major themes of quantitative and qualitative research. Our aim is to highlight areas that may be problematic or controversial (e.g. stepwise statistical procedures), underused (e.g. discriminant analysis), increasingly used (e.g. meta-analysis, structural equation modelling, qualitative content analysis) and emergent (e.g. realist tales of writing). Perspectives range from the technical and speculative to the controversial and critical. While deliberately not providing a 'cookbook' approach to research methods, we hope to provide enough material to help researchers to appreciate the diversity of potential methods and to adopt a more critical perspective in their own research consumption and production.  相似文献   
994.
The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption (VO2peak) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev x min(-1). The order of tests was randomized and they were separated by at least 2 days. Peak VO2 was significantly higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Peak ventilation volume increased as a function of crank rate and was higher (P < 0.05) at 80 than at 60 rev x min(-1). Peak heart rate was higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Furthermore, 70 and 80 rev x min(-1) resulted in an extended test time compared with 60 rev x min(-1). The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev x min(-1) should be used to elicit VO2peak and other physiological responses in arm crank ergometry.  相似文献   
995.
In any consideration of cultural diffusion, what matters is not only what happens to a cultural form when it arrives, but that it arrives. In the twentieth century, Latin America, like too many other areas of the world, has been a place of diplomatic turmoil, social inequality, political paranoia, capitalist exploitation and class conflict. However, despite all this, and through all this, it may be stated factually and without sentimentality, that it has also been a place where people have survived and thrived, worked, loved and played. Modern sport has brought to their play both unhappy moments of disillusion and disappointment and marvellous opportunities for illusion and pleasure. Modern sport, with its beauty spots and warts, is the reality and while there are things to criticize, there are also many things to applaud. Along with others, the English middle class played a not insignificant part in the arrival of modern sport in Latin America.  相似文献   
996.
This article, based on archival records, published documents, interviews with elite sportswomen and three regional case studies, deals with the radical social, economic, cultural and political changes in the early years of the Communist China, the consequent changes in women's lives and the eventual extraordinary impact on elite women's sport. It analyses the complicated relations between the communist system, gender ideology, sports policy, international politics and elite women's sport. With the establishment of a variety of sports institutions, systems and structures women in increasing numbers took part in competitive sport and produced even increasingly remarkable achievements.  相似文献   
997.
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   
998.
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   
999.
1000.
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   
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