全文获取类型
收费全文 | 10797篇 |
免费 | 85篇 |
国内免费 | 21篇 |
专业分类
教育 | 7458篇 |
科学研究 | 1443篇 |
各国文化 | 54篇 |
体育 | 667篇 |
综合类 | 6篇 |
文化理论 | 164篇 |
信息传播 | 1111篇 |
出版年
2022年 | 49篇 |
2021年 | 73篇 |
2020年 | 122篇 |
2019年 | 207篇 |
2018年 | 969篇 |
2017年 | 955篇 |
2016年 | 698篇 |
2015年 | 207篇 |
2014年 | 238篇 |
2013年 | 1231篇 |
2012年 | 239篇 |
2011年 | 465篇 |
2010年 | 448篇 |
2009年 | 293篇 |
2008年 | 361篇 |
2007年 | 476篇 |
2006年 | 138篇 |
2005年 | 185篇 |
2004年 | 252篇 |
2003年 | 180篇 |
2002年 | 110篇 |
2001年 | 123篇 |
2000年 | 164篇 |
1999年 | 114篇 |
1998年 | 97篇 |
1997年 | 88篇 |
1996年 | 82篇 |
1995年 | 57篇 |
1994年 | 64篇 |
1993年 | 52篇 |
1992年 | 102篇 |
1991年 | 95篇 |
1990年 | 86篇 |
1989年 | 92篇 |
1988年 | 99篇 |
1987年 | 76篇 |
1986年 | 104篇 |
1985年 | 97篇 |
1984年 | 83篇 |
1983年 | 88篇 |
1982年 | 78篇 |
1981年 | 54篇 |
1980年 | 47篇 |
1979年 | 68篇 |
1978年 | 63篇 |
1977年 | 54篇 |
1976年 | 61篇 |
1974年 | 45篇 |
1973年 | 42篇 |
1937年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
Lian Xue Aijun Ding Owen Cooper Xin Huang Wuke Wang Derong Zhou Zhaohua Wu Audra McClure-Begley Irina Petropavlovskikh Meinrat O Andreae Congbin Fu 《国家科学评论(英文版)》2021,8(6):114-121
Trans-Pacific transport of enhanced ozone plumes has been mainly attributed to fossil fuel combustion in Asia in spring, but less attention has been paid to vegetation fires in Asia. Here we show that the El Niño-Southern Oscillation (ENSO)-modulated fires in Southeast Asia, rather than Asian fossil fuel plumes, dominate the interannual variability of springtime trans-Pacific transport of ozone across the entire North Pacific Ocean. During El Niño springs, the intensified fires from both the Indochinese Peninsula and Indonesia, together with large-scale circulation anomalies, result in enhanced ozone plumes that stretch over 15 000 km in both the lower-middle and upper troposphere. This enhancement is also observed in the in situ measurements of ozone concentration, with an almost 10% increase at Mauna Loa Observatory, Hawaii, a unique site to monitor the long-distance transport over the North Pacific. This study reports an unexpectedly strong influence of vegetation fires, linked with climate variability, on global tropospheric chemistry and proves once more how complex the interactions in the climate system are. 相似文献
74.
75.
Families immigrating to Australia face many challenges integrating into the educational system, including language barriers and interrupted schooling. We have qualitatively evaluated the educational concerns of Arabic migrants from Sudan and Iraq to Melbourne, Victoria, Australia, a city that receives a high percentage of Australia's immigrants. Using an interactive paradigm incorporating focus group discussions for thematic analysis, we concluded that the parents’ frame of reference for education was a more didactic style of learning. Parents viewed education as an essential part of the way forward for their children in Australia. However, it was stressful for them to try to cope with a new host nation's expectation of their involvement in their children's education while at the same time dealing with a language barrier. Professionals should look to empower parents with structural information about the key elements of the educational curriculum with minimal reliance on written technical language and match their expectations of parental involvement to the situation of the parents. 相似文献
76.
77.
78.
79.
80.
Chris Bishop Lucas A. Pereira Valter P. Reis Paul Read Anthony N. Turner Irineu Loturco 《Journal of sports sciences》2020,38(11-12):1296-1303
ABSTRACT The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists. 相似文献