全文获取类型
收费全文 | 76076篇 |
免费 | 3070篇 |
国内免费 | 27篇 |
专业分类
79173篇 |
出版年
2020年 | 710篇 |
2019年 | 934篇 |
2018年 | 1277篇 |
2017年 | 1338篇 |
2016年 | 1424篇 |
2015年 | 1033篇 |
2014年 | 1209篇 |
2013年 | 5761篇 |
2012年 | 2226篇 |
2011年 | 2391篇 |
2010年 | 1488篇 |
2009年 | 1467篇 |
2008年 | 2072篇 |
2007年 | 2140篇 |
2006年 | 1918篇 |
2005年 | 1716篇 |
2004年 | 1604篇 |
2003年 | 1508篇 |
2002年 | 1636篇 |
2001年 | 2461篇 |
2000年 | 2407篇 |
1999年 | 1844篇 |
1998年 | 855篇 |
1997年 | 762篇 |
1996年 | 790篇 |
1995年 | 693篇 |
1992年 | 1562篇 |
1991年 | 1460篇 |
1990年 | 1431篇 |
1989年 | 1316篇 |
1988年 | 1309篇 |
1987年 | 1240篇 |
1986年 | 1308篇 |
1985年 | 1338篇 |
1984年 | 1108篇 |
1983年 | 1004篇 |
1982年 | 722篇 |
1981年 | 725篇 |
1979年 | 1194篇 |
1978年 | 864篇 |
1975年 | 972篇 |
1974年 | 1092篇 |
1973年 | 1200篇 |
1972年 | 987篇 |
1971年 | 945篇 |
1970年 | 872篇 |
1969年 | 859篇 |
1968年 | 1114篇 |
1967年 | 1013篇 |
1966年 | 866篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
William Alex Pridemore PhD Adam Trahan MA Mitchell B. Chamlin PhD 《Suicide & life-threatening behavior》2009,39(6):659-670
There is substantial evidence of detrimental psychological sequelae following disasters, including terrorist attacks. The effect of these events on extreme responses such as suicide, however, is unclear. We tested competing hypotheses about such effects by employing autoregressive integrated moving average techniques to model the impact of September 11 and the Oklahoma City bombing on monthly suicide counts at the local, state, and national level. Unlike prior studies that provided conflicting evidence, rigorous time series techniques revealed no support for an increase or decrease in suicides following these events. We conclude that while terrorist attacks produce subsequent psychological morbidity and may affect self and collective efficacy well beyond their immediate impact, these effects are not strong enough to influence levels of suicide mortality. 相似文献
12.
13.
14.
15.
16.
17.
Leigh M. Riby Timothy J. Perfect Brian T. Stollery 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》2004,57(2):241-267
Previous research demonstrates that older adults are poor at dual tasking, but there is less agreement on whether their decrement is worse than that predicted from single-task performance. This study investigated whether task domain moderates dual-task costs in old age. In two experiments, young and older adults retrieved either previously learned associates (episodic retrieval) or overlearned category members (semantic retrieval) under single or working-memory load conditions, using cued recall (Experiment 1) and recognition (Experiment 2) procedures. In both experiments the proportional costs of dual tasking were age invariant for semantic retrieval but were particularly marked for episodic retrieval, although the size of the age effect was reduced in recognition compared to cued recall. The data suggest that age effects in dual tasking may be domain specific. 相似文献
18.
19.
20.