全文获取类型
收费全文 | 22924篇 |
免费 | 363篇 |
国内免费 | 30篇 |
专业分类
教育 | 16523篇 |
科学研究 | 1988篇 |
各国文化 | 279篇 |
体育 | 1721篇 |
综合类 | 34篇 |
文化理论 | 189篇 |
信息传播 | 2583篇 |
出版年
2022年 | 136篇 |
2021年 | 231篇 |
2020年 | 368篇 |
2019年 | 506篇 |
2018年 | 712篇 |
2017年 | 791篇 |
2016年 | 731篇 |
2015年 | 440篇 |
2014年 | 595篇 |
2013年 | 4320篇 |
2012年 | 577篇 |
2011年 | 647篇 |
2010年 | 501篇 |
2009年 | 474篇 |
2008年 | 537篇 |
2007年 | 527篇 |
2006年 | 461篇 |
2005年 | 393篇 |
2004年 | 375篇 |
2003年 | 335篇 |
2002年 | 387篇 |
2001年 | 428篇 |
2000年 | 411篇 |
1999年 | 412篇 |
1998年 | 215篇 |
1997年 | 238篇 |
1996年 | 257篇 |
1995年 | 215篇 |
1994年 | 215篇 |
1993年 | 198篇 |
1992年 | 303篇 |
1991年 | 307篇 |
1990年 | 333篇 |
1989年 | 312篇 |
1988年 | 295篇 |
1987年 | 250篇 |
1986年 | 260篇 |
1985年 | 323篇 |
1984年 | 267篇 |
1983年 | 256篇 |
1982年 | 197篇 |
1981年 | 207篇 |
1980年 | 176篇 |
1979年 | 240篇 |
1978年 | 215篇 |
1977年 | 194篇 |
1976年 | 160篇 |
1975年 | 129篇 |
1974年 | 120篇 |
1973年 | 147篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
871.
872.
Harris AP 《Death education》1980,4(1):21-27
A training program of paraprofessionals was developed in a university teaching hospital. Trainees were exposed to seminars and a supervised practicum. The objectives of the experience included sensitization of persons in the natural helping network to (a) psychosocial needs of seriously ill persons and their families, (b) experience and comfort in interaction with such persons; (c) the structure of the health care delivery system, and (d) the usefulness of peer support groups. 相似文献
873.
J A Poteet 《Exceptional children》1968,34(10):760-761
874.
875.
876.
877.
878.
In three experiments, rats received pairings of flavor conditioned stimuli with polycose unconditioned stimuli, in either
a simultaneous or a sequential relation. Both temporal relations produced excellent conditioned increases in consumption of
the flavors. Separate presentation of the flavors resulted in extinction in both cases. However, restoring the pairing of
the flavor with polycose resulted in reconditioning only with the sequential, not with the simultaneous, relation. 相似文献
879.
880.
Soper C Hume PA 《Sports biomechanics / International Society of Biomechanics in Sports》2004,3(2):237-248
Coaches, sport scientists and researchers assess rowing performance on-water and on a variety of ergometers. Ergometers are frequently used because of the easier assessment environment. However, there is limited information on the ability of rowers to reproduce mean power or time-trial time when using different rowing ergometers (Concept II and RowPerfect) or completing tests over different distances (500 m versus 2000 m races). To test the efficacy of an intervention on a rower's ability to produce power, or to monitor that ability, it is essential to determine a reliable rowing performance test. The per cent standard error of measurement in performance (assessed by mean power and time-trial time) of fifteen national standard rowers was determined for five repeated 500 m and two repeated 2000 m races on a Concept II and RowPerfect ergometer. The per cent standard error of measurement (% SEM) in mean power between 5x500m races, regardless of gender, was 2.8% (95% confidence limits (CL)=2.3 to 3.4%) for the Concept II ergometer and 3.3% (95% CL=2.5 to 3.9%) for the RowPerfect ergometer (n = 15). Over 2000 m the per cent standard error of measurement in mean power was 1.3% (95% CL 0.9 to 2.9%) for the Concept II ergometer and 3.3% (95% CL 2.2 to 7.0%) for the RowPerfect ergometer The results highlight an increase in per cent standard error of the mean during performance races of less than 2000m on the Concept II ergometer, and performance races on the RowPerfect ergometer compared with the Concept II ergometer over 500 m and 2000 m. The most appropriate protocol for testing the influence of an intervention on the ability of a rower to produce power would be 2000 m races on a Concept II ergometer. 相似文献