全文获取类型
收费全文 | 25118篇 |
免费 | 201篇 |
国内免费 | 21篇 |
专业分类
教育 | 18218篇 |
科学研究 | 2779篇 |
各国文化 | 125篇 |
体育 | 1487篇 |
综合类 | 6篇 |
文化理论 | 480篇 |
信息传播 | 2245篇 |
出版年
2021年 | 138篇 |
2020年 | 196篇 |
2019年 | 278篇 |
2018年 | 2519篇 |
2017年 | 2454篇 |
2016年 | 1945篇 |
2015年 | 376篇 |
2014年 | 430篇 |
2013年 | 2376篇 |
2012年 | 527篇 |
2011年 | 1076篇 |
2010年 | 1146篇 |
2009年 | 656篇 |
2008年 | 919篇 |
2007年 | 1406篇 |
2006年 | 297篇 |
2005年 | 592篇 |
2004年 | 686篇 |
2003年 | 572篇 |
2002年 | 308篇 |
2001年 | 448篇 |
2000年 | 316篇 |
1999年 | 254篇 |
1998年 | 118篇 |
1997年 | 173篇 |
1996年 | 133篇 |
1995年 | 123篇 |
1994年 | 144篇 |
1993年 | 110篇 |
1992年 | 181篇 |
1991年 | 197篇 |
1990年 | 192篇 |
1989年 | 198篇 |
1988年 | 165篇 |
1987年 | 158篇 |
1986年 | 167篇 |
1985年 | 205篇 |
1984年 | 160篇 |
1983年 | 151篇 |
1982年 | 129篇 |
1981年 | 122篇 |
1980年 | 115篇 |
1979年 | 163篇 |
1978年 | 131篇 |
1977年 | 116篇 |
1976年 | 93篇 |
1975年 | 112篇 |
1974年 | 100篇 |
1973年 | 107篇 |
1971年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
C Uzelac 《Bulletin of the Medical Library Association》1970,58(4):554-558
The growing recognition of the need for humanities taught in schools of medicine is affecting acquisitions policies of medical libraries. This paper presents results of a survey conducted in various medical school libraries to evaluate the availability of humanities literature in their collections. 相似文献
992.
993.
994.
995.
996.
997.
The aim of the present study was to examine the factorial validity of the Test of Performance Strategies (TOPS; Thomas et al., 1999) among adolescent athletes using confirmatory factor analysis. The TOPS was designed to assess eight psychological strategies used in competition (i.e. activation, automaticity, emotional control, goal-setting, imagery, negative thinking, relaxation and self-talk,) and eight used in practice (the same strategies except negative thinking is replaced by attentional control). National-level athletes (n = 584) completed the 64-item TOPS during training camps. Fit indices provided partial support for the overall measurement model for the competition items (robust comparative fit index = 0.92, Tucker-Lewis index = 0.88, root mean square error of approximation = 0.05) but minimal support for the training items (robust comparative fit index = 0.86, Tucker-Lewis index = 0.81, root mean square error of approximation = 0.06). For the competition items, the automaticity, goal-setting, relaxation and self-talk scales showed good fit, whereas the activation, emotional control, imagery and negative thinking scales did not. For the practice items, the attentional control, emotional control, goal-setting, imagery and self-talk scales showed good fit, whereas the activation, automaticity and relaxation scales did not. Overall, it appears that the factorial validity of the TOPS for use with adolescents is questionable at present and further development is required. 相似文献
998.
James CR Sizer PS Starch DW Lockhart TE Slauterbeck J 《Research quarterly for exercise and sport》2004,75(1):31-38
Women are more prone to anterior cruciate ligament (ACL) injury during cutting sports than men. The purpose of this study was to examine knee kinematic and ground reaction forces (GRF) differences between genders during cutting. Male and female athletes performed cutting trials while force platform and video data were recorded (180 Hz). Differences (p < . 05) were observed between groups for knee flexion at contact and GRF at maximum knee flexion. Women averaged 5.8 degrees less flexion at contact and 1.0 N. (kg x m x s(-1))(-1) greater GRF at maximum flexion. Knee range of motion and peak GRF variables were not significantly different, but women had greater values. Women exhibited technique characteristics believed to increase ACL injury risk, but men exhibiting similar characteristics were also observed and could also be at risk. 相似文献
999.
Mangus BC Wallmann HW Ledford M 《Sports biomechanics / International Society of Biomechanics in Sports》2004,3(2):209-220
The aim of our study was to determine if any immediate changes in balance were discernable in college soccer players after a specially designed heading session. Eight male and two female skilled collegiate soccer players had a baseline balance pre-test using the Balance Master, followed by heading 20 balls kicked consecutively by a teammate from the touchline to a point near the goal, which was followed by a post-test using the same testing technique. Paired t-tests were used to compare balance ability between pre- and post-test conditions. There was no difference in balance pre- to post-test (85.3% and 86.2% respectively). No significant difference was noted from pre- to post-test in the mean equilibrium scores for conditions three through six on the Sensory Organization Test, with the exception of condition four, which revealed a significant increase from pre- to post-test. We concluded that an acute session of heading soccer balls may not result in balance changes in collegiate soccer players. 相似文献
1000.