全文获取类型
收费全文 | 3758篇 |
免费 | 41篇 |
专业分类
教育 | 2585篇 |
科学研究 | 315篇 |
各国文化 | 61篇 |
体育 | 384篇 |
综合类 | 2篇 |
文化理论 | 50篇 |
信息传播 | 402篇 |
出版年
2022年 | 19篇 |
2021年 | 41篇 |
2020年 | 76篇 |
2019年 | 119篇 |
2018年 | 127篇 |
2017年 | 124篇 |
2016年 | 107篇 |
2015年 | 71篇 |
2014年 | 123篇 |
2013年 | 892篇 |
2012年 | 94篇 |
2011年 | 101篇 |
2010年 | 80篇 |
2009年 | 83篇 |
2008年 | 83篇 |
2007年 | 78篇 |
2006年 | 95篇 |
2005年 | 84篇 |
2004年 | 77篇 |
2003年 | 72篇 |
2002年 | 55篇 |
2001年 | 50篇 |
2000年 | 56篇 |
1999年 | 51篇 |
1998年 | 55篇 |
1997年 | 45篇 |
1996年 | 39篇 |
1995年 | 33篇 |
1994年 | 31篇 |
1993年 | 38篇 |
1992年 | 30篇 |
1991年 | 36篇 |
1990年 | 41篇 |
1989年 | 37篇 |
1988年 | 40篇 |
1987年 | 39篇 |
1986年 | 31篇 |
1985年 | 25篇 |
1984年 | 34篇 |
1983年 | 34篇 |
1982年 | 26篇 |
1981年 | 18篇 |
1980年 | 23篇 |
1979年 | 35篇 |
1978年 | 28篇 |
1977年 | 24篇 |
1976年 | 25篇 |
1974年 | 19篇 |
1973年 | 20篇 |
1971年 | 15篇 |
排序方式: 共有3799条查询结果,搜索用时 593 毫秒
21.
22.
23.
24.
25.
Matt King 《Al-Masaq: Islam & the Medieval Mediterranean》2017,29(3):221-234
The release of the Old World Drought Atlas (OWDA) in November 2015 provides historians with an unprecedented glimpse into the climate of the medieval world. Through the careful examination of tree-ring data provided by the OWDA, historians can better gauge how the environment affected the course of medieval Mediterranean history, particularly in times and places where textual data is sparse, such as North Africa. The case studies of the Norman conquest of the coast of Ifrīqiyya in the 1140s and the invasion by the Banū Hilāl in the mid-eleventh century show the utility of the OWDA for gaining a better understanding the medieval Mediterranean. In particular, OWDA data shows that the arrival of the Banū Hilāl into Ifrīqiyya coincided with a period of extended drought that is not documented in the written sources and suggests that increased competition for scarce resources was instrumental to their entrance into the region. 相似文献
26.
Thomas A. C. Reydon 《Metascience》2015,24(2):259-264
27.
28.
Georga J. Longhurst Danya M. Stone Kate Dulohery Deirdre Scully Thomas Campbell Claire F. Smith 《Anatomical sciences education》2020,13(3):301-311
The Covid-19 pandemic has driven the fastest changes to higher education across the globe, necessitated by social distancing measures preventing face-to-face teaching. This has led to an almost immediate switch to distance learning by higher education institutions. Anatomy faces some unique challenges. Intrinsically, anatomy is a three-dimensional subject that requires a sound understanding of the relationships between structures, often achieved by the study of human cadaveric material, models, and virtual resources. This study sought to identify the approaches taken in the United Kingdom and Republic of Ireland to deliver anatomical education through online means. Data were collected from 14 different universities in the United Kingdom and Republic of Ireland and compared adopting a thematic analysis approach. Once themes were generated, they were collectively brought together using a strength, weakness, opportunity, threat (SWOT) analysis. Key themes included the opportunity to develop new online resources and the chance to engage in new academic collaborations. Academics frequently mentioned the challenge that time constrains could place on the quality and effectiveness of these resources; especially as in many cases the aim of these resources was to compensate for a lack of exposure to cadaveric exposure. Comparisons of the actions taken by multiple higher education institutions reveal the ways that academics have tried to balance this demand. Discussions will facilitate decisions being made by higher education institutions regarding adapting the curriculum and assessment methods in anatomy. 相似文献
29.
Richard Michael Page Ben Langley Mitchell James Finlay Matt Greig Christopher Brogden 《Journal of sports sciences》2020,38(5):568-575
ABSTRACTThis study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rad·s-1, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT. 相似文献
30.
Kenneth D. Smith John Paul Eddy Thomas C. Richards Paul N. Dixon 《The American journal of distance education》2013,27(2):5-13
Abstract An empirical examination of accredited American higher education institutions was conducted to obtain baseline data regarding distance education copyright, intellectual property, and antitrust concerns. Additionally, a multiple‐case study involving ten of the top thirty accredited distance education institutions in America was conducted. Policy approaches were examined for all institutions, and differences were discussed between public and private institutions as well as between the following Carnegie Classification institutions: Research I and II, Doctorate I and II, and Master's I and II. Data indicated that, out of the schools surveyed, 22% of the institutions in these Carnegie Classification categories published copyright and intellectual property policies on their institution's Web site. In the case study, it was found that 90% of the institutions centrally controlled their distance education program administration as well as the copyright and intellectual property policies related to it. 相似文献