全文获取类型
收费全文 | 41031篇 |
免费 | 1538篇 |
国内免费 | 11篇 |
专业分类
42580篇 |
出版年
2019年 | 468篇 |
2018年 | 678篇 |
2017年 | 621篇 |
2016年 | 752篇 |
2015年 | 540篇 |
2014年 | 608篇 |
2013年 | 3954篇 |
2012年 | 1086篇 |
2011年 | 1173篇 |
2010年 | 737篇 |
2009年 | 749篇 |
2008年 | 1068篇 |
2007年 | 1007篇 |
2006年 | 913篇 |
2005年 | 794篇 |
2004年 | 779篇 |
2003年 | 814篇 |
2002年 | 760篇 |
2001年 | 1265篇 |
2000年 | 1211篇 |
1999年 | 949篇 |
1998年 | 465篇 |
1996年 | 557篇 |
1995年 | 529篇 |
1994年 | 532篇 |
1993年 | 477篇 |
1992年 | 954篇 |
1991年 | 835篇 |
1990年 | 846篇 |
1989年 | 730篇 |
1988年 | 729篇 |
1987年 | 719篇 |
1986年 | 718篇 |
1985年 | 704篇 |
1984年 | 630篇 |
1983年 | 541篇 |
1982年 | 427篇 |
1981年 | 437篇 |
1979年 | 603篇 |
1978年 | 468篇 |
1975年 | 536篇 |
1974年 | 526篇 |
1973年 | 594篇 |
1972年 | 562篇 |
1971年 | 503篇 |
1970年 | 441篇 |
1969年 | 425篇 |
1968年 | 539篇 |
1967年 | 455篇 |
1966年 | 441篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Kathleen Forcier Laura R Stroud George D Papandonatos Brian Hitsman Meredith Reiches Jenelle Krishnamoorthy Raymond Niaura 《Health psychology》2006,25(6):723-739
A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity. 相似文献
32.
33.
34.
Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults. 相似文献
35.
George F. Parker M.D. 《Behavioral sciences & the law》2015,33(2-3):308-322
Indiana statute allows police to seize firearms without a warrant if the officer believes a person meets the law's definition of “dangerous.” Review of the use of this law in Marion County (Indianapolis), Indiana, showed that prosecutors filed petitions in court to retain weapons seized by police under this law 404 times between 2006 and 2013. Police removed weapons from people due to identification of a risk of suicide (68%) or violence (21%), or the presence of psychosis (16%). The firearm seizures occurred in the context of domestic disputes in 28% of cases and intoxication was noted in 26% of cases. There were significant demographic differences in the circumstances of firearm seizures and the firearms seized. The seized firearms were retained by the court at the initial hearing in 63% of cases; this retention was closely linked to the defendant's failure to appear at the hearing. The court dismissed 29% of cases at the initial hearing, closely linked to the defendant's presence at the hearing. In subsequent hearings of cases not dismissed, the court ordered the destruction of the firearms in 72% of cases, all when the individual did not appear in court, and dismissed 24% of the cases, all when the individual was present at the hearing. Overall, the Indiana law removed weapons from a small number of people, most of whom did not seek return of their weapons. The firearm seizure law thus functioned as a months-long cooling-off period for those who did seek the return of their guns. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
36.
37.
38.
39.
40.