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   18023篇
  免费   232篇
  国内免费   13篇
教育   13348篇
科学研究   1420篇
各国文化   159篇
体育   1393篇
综合类   8篇
文化理论   147篇
信息传播   1793篇
  2021年   123篇
  2020年   203篇
  2019年   330篇
  2018年   446篇
  2017年   478篇
  2016年   420篇
  2015年   283篇
  2014年   364篇
  2013年   3628篇
  2012年   362篇
  2011年   451篇
  2010年   290篇
  2009年   310篇
  2008年   425篇
  2007年   326篇
  2006年   394篇
  2005年   284篇
  2004年   262篇
  2003年   267篇
  2002年   287篇
  2001年   382篇
  2000年   355篇
  1999年   326篇
  1998年   180篇
  1997年   216篇
  1996年   229篇
  1995年   233篇
  1994年   188篇
  1993年   211篇
  1992年   283篇
  1991年   266篇
  1990年   257篇
  1989年   296篇
  1988年   285篇
  1987年   242篇
  1986年   246篇
  1985年   268篇
  1984年   219篇
  1983年   267篇
  1982年   209篇
  1981年   195篇
  1980年   188篇
  1979年   286篇
  1978年   209篇
  1977年   207篇
  1976年   176篇
  1975年   154篇
  1974年   153篇
  1973年   149篇
  1971年   122篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
91.
This article is principally concerned with how and why these 2 types of radio news developed. It discusses the culture, ethos and practices of the 2 services and, in particular, if and how each was influenced by the other. Much of the article is concerned about how the new commercial stations developed practices and styles that were consciously different from, and in some cases in direct opposition to, those at the BBC, both nationally and locally. The article argues that it was the BBC which adopted and integrated commercial radio’s style and practices, rather than, as is often supposed, the other way around.  相似文献   
92.
Self‐efficacy is a universal construct, but few validated measures exist for researchers in developing countries to use in assessing youths’ perceptions of their ability to achieve academic success. This study examined the cross‐cultural suitability and psychometric properties of an academic self‐efficacy scale (ASES) adapted for the Ghanaian context. ASES construct validity was assessed with a sample of 4,289 Ghanaian junior high‐school students and exploratory and confirmatory factor analysis. Invariance testing assessed the scale's measurement equivalence by gender and temporal stability of gender equivalence. The ASES is a valid, reliable one‐dimensional scale for assessing young Ghanaians’ perceptions of their academic capabilities, and it works equally well across genders. As adapted, ASES is a valid scale with utility for researchers examining predictors and effects of academic self‐efficacy. The ASES has important implications for decisions regarding investment in programs aimed at improving academic self‐efficacy of youth, both in sub‐Saharan Africa and the increasingly diverse American public schools.  相似文献   
93.
ABSTRACT

Participation in youth sport is positively associated with physical fitness and performance. The purpose of the current study was to examine if physical fitness measures during childhood and early adolescence predicted high school sport participation. Participants included youth in the Michigan State University Motor Performance Study. Measures consisted of the endurance shuttle run, Wells sit-and-reach, jump and reach, standing long jump, agility shuttle run and 30-yard dash. Individual, generalized estimating equation models were used to estimate the association between each measure and the odds of participating in high school sport. For both sexes, the endurance shuttle run and agility shuttle run were related to sport participation. For boys only, the long jump and 30-yard dash were also associated with sport participation. Better physical fitness and performance across several dimensions in childhood, including those related to motor skills, enhanced the likelihood of sport participation in high school.  相似文献   
94.
95.
96.
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks.  相似文献   
97.
Research in Higher Education - Since the turn of the twenty-first century, going to college has become increasingly financially difficult in the United States. Tuition prices continued to rise,...  相似文献   
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