全文获取类型
收费全文 | 536篇 |
免费 | 11篇 |
专业分类
教育 | 409篇 |
科学研究 | 19篇 |
各国文化 | 6篇 |
体育 | 48篇 |
综合类 | 1篇 |
文化理论 | 8篇 |
信息传播 | 56篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 12篇 |
2018年 | 23篇 |
2017年 | 27篇 |
2016年 | 18篇 |
2015年 | 14篇 |
2014年 | 17篇 |
2013年 | 136篇 |
2012年 | 13篇 |
2011年 | 18篇 |
2010年 | 10篇 |
2009年 | 15篇 |
2008年 | 12篇 |
2007年 | 10篇 |
2006年 | 12篇 |
2005年 | 8篇 |
2004年 | 15篇 |
2003年 | 11篇 |
2002年 | 4篇 |
2001年 | 8篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 14篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1980年 | 4篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1972年 | 2篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1968年 | 4篇 |
1966年 | 2篇 |
1931年 | 2篇 |
1930年 | 2篇 |
排序方式: 共有547条查询结果,搜索用时 15 毫秒
151.
152.
153.
154.
The aim of the present study was to investigate the relationship between physiological and performance responses during repeated 6-over fast-bowling spells. Six, first-class, medium-fast bowlers performed 2x6-over spells separated by 45 min of light activity. The 6-over spells were based on the Cricket Australia fast bowling skills test that is a set order of deliveries at a grid-based target. Ball speed, accuracy and full and final 5-m run-up speed were measured on each ball. Nude mass, heart rate, core temperature, capillary blood lactate, pH and glucose, perceptual measures of RPE and muscle soreness (MS) and repeated vertical jump efforts were measured prior to, during and following each spell. Results indicated no decrement (P=0.41) and small effect sizes (d<0.2) in bowling speed (125.7+/-5.1 and 125.4+/-4.5 km.h(-1)) or accuracy (40.4+/-16.1 and 41.6+/-18.0 AU) between spells 1 and 2. No differences (P=0.6-0.8) were present between spells for heart rate, core temperature, lactate, pH, glucose, RPE, MS or vertical jump. Only final 5-m run-up speed showed a large correlation with ball speed (r=0.70), while accuracy and speed were not correlated (r=0.05). In conclusion, repeated 6-over spells in well-trained bowlers results in minimal performance decrement in mild conditions (22 degrees C). As faster bowlers had faster final 5-m run-up speeds, the maintenance of high final 5-m run-up speeds might be important to maintaining bowling speed. Future research should also include a third bowling spell and warmer environmental conditions. 相似文献
155.
156.
Claire Mitchell 《Journal of Cultural Economics》1989,13(2):69-79
157.
OBJECTIVE: This paper explores the characteristics associated with decisions to adopt or discontinue the use of filtering software, including a critical analysis of some explanations about why it is used or not used in households with children and adolescents. METHOD: This study consisted of a national telephone survey of households in the United States with youth (10 and 17 years) who use the Internet regularly. Interviews were completed with one youth in the appropriate age group and a parent or caretaker. RESULTS: Thirty-three percent of parents reported using filtering or blocking software, with an additional 5% having discontinued its use within the past year. Parents were more likely to adopt filtering software if they had younger children (10--15 years), a high level of concern about exposure to sexual material on the Internet, more extensive knowledge of what their child did online, low trust in the child's ability to use the Internet responsibly, and if the child used America Online (AOL). Using the Internet for school assignments was associated with not having filtering software. CONCLUSION: Findings suggest the need for (1) evaluation research of filter programs used in a real family context and (2) the development of a variety of strategies to prevent exposure to inappropriate material for youth of different ages. 相似文献
158.
159.
160.
The aims of this study were to examine the effect of shaft flexibility on the performance of junior golfers and to determine whether there is a relationship between golfers' physical characteristics (16 anthropometric measures, age, experience, strength), performance and shaft flexibility. We assessed the performance of 30 male golfers, aged 7-10 years, with three 7-iron golf clubs of different shaft flexibility at a driving range. The performance parameters measured for equipment evaluation were ball distance achieved, shot dispersion and impact position of the ball on the clubface. The results suggest that there is no particular shaft flex suitable for the age group considered and that experience, strength and arm span are the significant factors when selecting optimal shaft flexibility for children. 相似文献