全文获取类型
| 收费全文 | 34145篇 |
| 免费 | 402篇 |
| 国内免费 | 15篇 |
专业分类
| 教育 | 24905篇 |
| 科学研究 | 3203篇 |
| 各国文化 | 219篇 |
| 体育 | 2259篇 |
| 综合类 | 13篇 |
| 文化理论 | 563篇 |
| 信息传播 | 3400篇 |
出版年
| 2022年 | 167篇 |
| 2021年 | 263篇 |
| 2020年 | 385篇 |
| 2019年 | 613篇 |
| 2018年 | 2914篇 |
| 2017年 | 2812篇 |
| 2016年 | 2248篇 |
| 2015年 | 557篇 |
| 2014年 | 775篇 |
| 2013年 | 4562篇 |
| 2012年 | 877篇 |
| 2011年 | 1372篇 |
| 2010年 | 1316篇 |
| 2009年 | 906篇 |
| 2008年 | 1172篇 |
| 2007年 | 1630篇 |
| 2006年 | 492篇 |
| 2005年 | 798篇 |
| 2004年 | 824篇 |
| 2003年 | 719篇 |
| 2002年 | 476篇 |
| 2001年 | 483篇 |
| 2000年 | 419篇 |
| 1999年 | 363篇 |
| 1998年 | 205篇 |
| 1997年 | 225篇 |
| 1996年 | 242篇 |
| 1995年 | 237篇 |
| 1994年 | 186篇 |
| 1993年 | 202篇 |
| 1992年 | 325篇 |
| 1991年 | 304篇 |
| 1990年 | 301篇 |
| 1989年 | 298篇 |
| 1988年 | 258篇 |
| 1987年 | 303篇 |
| 1986年 | 264篇 |
| 1985年 | 290篇 |
| 1984年 | 237篇 |
| 1983年 | 200篇 |
| 1982年 | 174篇 |
| 1981年 | 158篇 |
| 1980年 | 136篇 |
| 1979年 | 241篇 |
| 1978年 | 175篇 |
| 1977年 | 153篇 |
| 1976年 | 138篇 |
| 1975年 | 132篇 |
| 1974年 | 135篇 |
| 1971年 | 119篇 |
排序方式： 共有10000条查询结果，搜索用时 375 毫秒
1.
Research in Higher Education - Given the significant need to increase and diversify graduate enrollments within computing fields, it is vital to understand what shapes students’ pathways to... 相似文献
2.
David Sánchez-Oliva Rebecca M. Leech Alberto Grao-Cruces Irene Esteban-Cornejo Carmen Padilla-Moledo Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069
ABSTRACTThe aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time. 相似文献
3.
4.
5.
6.
7.
8.
9.
Anthony J. Sadar 《Science & Education》2018,27(1-2):233-235
10.
Cultural Studies of Science Education - The retention of underrepresented students remains a significant challenge in the STEM (Science, Technology, Engineering and Math) disciplines. A broad range... 相似文献