全文获取类型
收费全文 | 8504篇 |
免费 | 70篇 |
国内免费 | 20篇 |
专业分类
教育 | 5929篇 |
科学研究 | 1110篇 |
各国文化 | 29篇 |
体育 | 466篇 |
综合类 | 6篇 |
文化理论 | 137篇 |
信息传播 | 917篇 |
出版年
2022年 | 37篇 |
2021年 | 45篇 |
2020年 | 85篇 |
2019年 | 126篇 |
2018年 | 840篇 |
2017年 | 873篇 |
2016年 | 613篇 |
2015年 | 160篇 |
2014年 | 168篇 |
2013年 | 787篇 |
2012年 | 202篇 |
2011年 | 424篇 |
2010年 | 403篇 |
2009年 | 255篇 |
2008年 | 315篇 |
2007年 | 439篇 |
2006年 | 105篇 |
2005年 | 155篇 |
2004年 | 226篇 |
2003年 | 159篇 |
2002年 | 89篇 |
2001年 | 106篇 |
2000年 | 145篇 |
1999年 | 89篇 |
1998年 | 72篇 |
1997年 | 75篇 |
1996年 | 62篇 |
1995年 | 42篇 |
1994年 | 45篇 |
1993年 | 33篇 |
1992年 | 75篇 |
1991年 | 69篇 |
1990年 | 60篇 |
1989年 | 62篇 |
1988年 | 74篇 |
1987年 | 58篇 |
1986年 | 78篇 |
1985年 | 70篇 |
1984年 | 55篇 |
1983年 | 69篇 |
1982年 | 53篇 |
1981年 | 40篇 |
1980年 | 29篇 |
1979年 | 52篇 |
1978年 | 49篇 |
1977年 | 37篇 |
1976年 | 42篇 |
1975年 | 31篇 |
1974年 | 33篇 |
1973年 | 33篇 |
排序方式: 共有8594条查询结果,搜索用时 0 毫秒
131.
Abbie E. Smith-Ryan Eric T. Trexler Hailee L. Wingfield Malia N.M. Blue 《Journal of sports sciences》2016,34(21):2038-2046
The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m2) were randomly assigned to ten 1-min high-intensity intervals (90%VO2 peak, 1 min recovery) or five 2-min high-intensity intervals (80–100% VO2 peak, 1 min recovery) or control. Peak oxygen uptake (VO2 peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (?18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (?55.1 ± 16.4 s; P = 0.001); non-significant increase in VO2 peak (?2.36 ± 1.34 ml · kg?1 · min?1; P = 0.185); and a significant decrease in fat mass (FM) (??1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women. 相似文献
132.
1.Introduction
The reproduction systems of 3D images without using eyeglasses and other special accessories has always attracted attention and aroused great interest of developers and consumers of such equipment because of totally accurate image and method of its presentation.Such systems can be used and are already partially used in advertising,television,different devices (i.e.smartphones,tablet computers),at the exhibitions,etc.,as well as in various technical applications,training systems,simulators,etc. 相似文献
133.
David S. Haydon Ross A. Pinder Paul N. Grimshaw William S. P. Robertson 《Sports Engineering》2016,19(3):177-184
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost. 相似文献
134.
135.
136.
137.
Rats were exposed twice in a rotated sequence to a series of six mazes, consisting of hexagonal alleys, balanced for different alley length and structural complexity. Locomotor activity increased with alley length and decreased with structural complexity of the mazes. Locomotion became less stereotyped with increased experience, showing an increasing number of turns, less constant velocity, loss of the initial preference for outward leading alleys and weakening of the forward tendency at reentry from side alleys into hexagonal alleys. In contrast to these qualitative changes of locomotion, the amount of activity remained almost unchanged throughout the experiment. The results suggest that these increases in locomotion complexity depend upon complex interactions between experience and stimulus content of the mazes. 相似文献
138.
139.
140.
Visual cues have an important role in food preference for both rats and humans. Here, we aim to isolate the effects of numerosity, density, and surface area on food preference and running speed in rats, by using a forced-choice maze paradigm. In Experiment 1, rats preferred and ran faster for a group of multiple smaller pellets rather than a single large pellet, corroborating previous research (Capaldi, Miller, & Alptekin Journal of Experimental Psychology: Animal Behavior Processes, 15(1), 75–80, 1989). Further experiments tested the prevailing hypothesis that multiple food pieces are more reinforcing because they occupy a larger surface area. Experiment 2 controlled for numerosity by utilizing a continuous food: mashed potatoes flattened to cover a larger surface area or rounded into a ball. The rats preferred and ran faster for the flattened potatoes, suggesting surface area plays a role in quantity estimations. Finally, in Experiment 3, rats displayed no preference or difference in running speed between a group of scattered and clustered pellets when number of pellets were kept constant. Taken together, these results suggest that density has an important role in food perception—that is, the rewarding effect of higher numerosity or larger surface area is removed when the food does not fill out the entire space. Alternative explanations and implications for human diet are discussed. 相似文献