全文获取类型
收费全文 | 13562篇 |
免费 | 44篇 |
国内免费 | 1篇 |
专业分类
教育 | 10220篇 |
科学研究 | 1339篇 |
各国文化 | 54篇 |
体育 | 598篇 |
综合类 | 1篇 |
文化理论 | 395篇 |
信息传播 | 1000篇 |
出版年
2024年 | 4篇 |
2023年 | 8篇 |
2022年 | 15篇 |
2021年 | 34篇 |
2020年 | 60篇 |
2019年 | 121篇 |
2018年 | 2279篇 |
2017年 | 2196篇 |
2016年 | 1652篇 |
2015年 | 173篇 |
2014年 | 201篇 |
2013年 | 531篇 |
2012年 | 282篇 |
2011年 | 747篇 |
2010年 | 892篇 |
2009年 | 492篇 |
2008年 | 708篇 |
2007年 | 1206篇 |
2006年 | 119篇 |
2005年 | 438篇 |
2004年 | 483篇 |
2003年 | 399篇 |
2002年 | 160篇 |
2001年 | 35篇 |
2000年 | 41篇 |
1999年 | 23篇 |
1998年 | 34篇 |
1997年 | 33篇 |
1996年 | 13篇 |
1995年 | 19篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 16篇 |
1990年 | 19篇 |
1989年 | 18篇 |
1988年 | 5篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1977年 | 5篇 |
1974年 | 5篇 |
1970年 | 3篇 |
1968年 | 3篇 |
1948年 | 3篇 |
1852年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
Emer Van Ryswyk Richard Weeks Laura Bandick Michaela O’Keefe Andrew Vakulin Peter Catcheside 《European Journal of Sport Science》2017,17(2):144-151
Objectives: To improve well-being and performance indicators in a group of Australian Football League (AFL) players via a six-week sleep optimisation programme. Design: Prospective intervention study following observations suggestive of reduced sleep and excessive daytime sleepiness in an AFL group. Methods: Athletes from the Adelaide Football Club were invited to participate if they had played AFL senior-level football for 1–5 years, or if they had excessive daytime sleepiness (Epworth Sleepiness Scale [ESS] >10), measured via ESS. An initial education session explained normal sleep needs, and how to achieve increased sleep duration and quality. Participants (n?=?25) received ongoing feedback on their sleep, and a mid-programme education and feedback session. Sleep duration, quality and related outcomes were measured during week one and at the conclusion of the six-week intervention period using sleep diaries, actigraphy, ESS, Pittsburgh Sleep Quality Index, Profile of Mood States, Training Distress Scale, Perceived Stress Scale and the Psychomotor Vigilance Task. Results: Sleep diaries demonstrated an increase in total sleep time of approximately 20?min (498.8?±?53.8 to 518.7?±?34.3; p?<?.05) and a 2% increase in sleep efficiency (p?<?0.05). There was a corresponding increase in vigour (p?<?0.001) and decrease in fatigue (p?<?0.05). Conclusions: Improvements in measures of sleep efficiency, fatigue and vigour indicate that a sleep optimisation programme may improve athletes’ well-being. More research is required into the effects of sleep optimisation on athletic performance. 相似文献
94.
95.
This paper describes the French initiative in materials research against both a national and an international background,
in an attempt to disentangle the local circumstances, which prompted this governmental initiative, and to characterize the
specific profile of materials research in France. In presenting a biography of the interdisciplinary program in materials
research (PIRMAT), we argue that: i) the PIRMAT denotes a failure of the French science policy in materials research; ii)
the leadership of the CNRS led to a specific style of research, quite different from the engineering approach of Materials
Science and Engineering, and characteristic of a French style in materials research. 相似文献
96.
97.
Kaare Aagaard 《Minerva》2017,55(3):279-297
This article outlines the evolution of a national research funding system over a timespan of more than 40 years and analyzes the development from a rather stable Humboldt-inspired floor funding model to a complex multi-tiered system where new mechanisms continually have been added on top of the system. Based on recent contributions to Historical Institutionalism it is shown how layering and displacement processes gradually have changed the funding system along a number of dimensions and thus how a series of minor adjustments over time has led to a transformation of the system as a whole. The analysis also highlights the remarkable resistance of the traditional academically oriented research council system towards restructuring. Due to this resistance the political system has, however, circumvented the research council system and implemented change through other channels of the funding system. For periods of time these strategies have marginalized the role of the councils. 相似文献
98.
99.
Andrew Post J. Michio Clark D. G. E. Robertson T. Blaine Hoshizaki Michael D. Gilchrist 《Sports Engineering》2017,20(2):111-119
Brain injury research in sport employs a variety of physical models equipped with accelerometers. These acceleration signals are commonly processed using filters. The purpose of this research was to determine the effect of applying filters with different cutoff frequencies to the acceleration signals used as input for finite element modeling of the brain. Signals were generated from reconstructions of concussion events from American football and ice hockey in the laboratory using a Hybrid III headform. The resulting acceleration signals were used as input for the University College Dublin Brain Trauma Model after being processed with filters. The results indicated that using a filter with a cutoff of 300 Hz or higher had little effect on the resulting strain measures. In some cases there was some effect of the filters on the peak linear (8–30g) and rotational measures (1000–4000 rad/s2), but little effect on the finite element strain result (approximately 2–6 %). The short duration and high magnitude accelerations, such as the puck impact, were most affected by the cutoff frequency of different filters. 相似文献
100.