全文获取类型
收费全文 | 27907篇 |
免费 | 427篇 |
国内免费 | 17篇 |
专业分类
教育 | 19833篇 |
科学研究 | 2708篇 |
各国文化 | 235篇 |
体育 | 2162篇 |
综合类 | 20篇 |
文化理论 | 307篇 |
信息传播 | 3086篇 |
出版年
2022年 | 165篇 |
2021年 | 278篇 |
2020年 | 422篇 |
2019年 | 653篇 |
2018年 | 1438篇 |
2017年 | 1456篇 |
2016年 | 1167篇 |
2015年 | 511篇 |
2014年 | 755篇 |
2013年 | 4889篇 |
2012年 | 791篇 |
2011年 | 971篇 |
2010年 | 792篇 |
2009年 | 664篇 |
2008年 | 760篇 |
2007年 | 817篇 |
2006年 | 471篇 |
2005年 | 548篇 |
2004年 | 536篇 |
2003年 | 473篇 |
2002年 | 409篇 |
2001年 | 538篇 |
2000年 | 466篇 |
1999年 | 407篇 |
1998年 | 250篇 |
1997年 | 236篇 |
1996年 | 251篇 |
1995年 | 238篇 |
1994年 | 190篇 |
1993年 | 198篇 |
1992年 | 329篇 |
1991年 | 309篇 |
1990年 | 306篇 |
1989年 | 303篇 |
1988年 | 269篇 |
1987年 | 309篇 |
1986年 | 277篇 |
1985年 | 321篇 |
1984年 | 265篇 |
1983年 | 217篇 |
1982年 | 199篇 |
1981年 | 176篇 |
1980年 | 148篇 |
1979年 | 263篇 |
1978年 | 197篇 |
1977年 | 170篇 |
1976年 | 150篇 |
1975年 | 145篇 |
1974年 | 154篇 |
1971年 | 130篇 |
排序方式: 共有10000条查询结果,搜索用时 272 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.
Anthony J. Sadar 《Science & Education》2018,27(1-2):233-235
6.
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
7.
8.
9.
10.
Harry F. Dorrell Joseph M. Moore Mark F. Smith Thomas I. Gee 《Journal of sports sciences》2019,37(1):67-73
This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54–0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6–8.8%) were found for all variables, with SWC ranging 1.7–7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance. 相似文献