全文获取类型
收费全文 | 57059篇 |
免费 | 2350篇 |
国内免费 | 21篇 |
专业分类
59430篇 |
出版年
2020年 | 526篇 |
2019年 | 642篇 |
2018年 | 906篇 |
2017年 | 940篇 |
2016年 | 1014篇 |
2015年 | 768篇 |
2014年 | 869篇 |
2013年 | 4151篇 |
2012年 | 1628篇 |
2011年 | 1605篇 |
2010年 | 999篇 |
2009年 | 958篇 |
2008年 | 1395篇 |
2007年 | 1440篇 |
2006年 | 1226篇 |
2005年 | 1174篇 |
2004年 | 1097篇 |
2003年 | 1037篇 |
2002年 | 1077篇 |
2001年 | 1849篇 |
2000年 | 1771篇 |
1999年 | 1322篇 |
1998年 | 583篇 |
1996年 | 534篇 |
1992年 | 1212篇 |
1991年 | 1145篇 |
1990年 | 1176篇 |
1989年 | 1024篇 |
1988年 | 1035篇 |
1987年 | 976篇 |
1986年 | 1028篇 |
1985年 | 1103篇 |
1984年 | 843篇 |
1983年 | 772篇 |
1982年 | 542篇 |
1981年 | 533篇 |
1979年 | 968篇 |
1978年 | 658篇 |
1977年 | 604篇 |
1976年 | 584篇 |
1975年 | 821篇 |
1974年 | 961篇 |
1973年 | 1014篇 |
1972年 | 847篇 |
1971年 | 802篇 |
1970年 | 796篇 |
1969年 | 757篇 |
1968年 | 1011篇 |
1967年 | 884篇 |
1966年 | 787篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
801.
The prediction of drug use among college students from MMPI, MCMI, and sensation seeking scales 总被引:1,自引:0,他引:1
This study examines the ability of five self-report assessment measures to predict college students' drug use across 12 pharmacological drug categories. Subjects were 125 female and 61 male university undergraduate students. The test battery included the following instruments: the Psychopathic Deviancy (Pd) scale of the Minnesota Multiphasic Personality Inventory (MMPI); the MacAndrew Alcoholism scale (MAC), a special scale of the MMPI; the Sensation Seeking Scale (SSS); the Millon Alcohol Abuse Scale; and the Millon Drug Abuse Scale. Scores from these instruments were utilized in linear combinations to predict individual drug use outcomes as well as polydrug versus single drug use patterns. The drug categories included in this investigation are coffee, tobacco, alcohol, marijuana, tranquilizers, depressants, amphetamines, LSD, other hallucinogens, solvents, narcotics, and cocaine. Results demonstrate significant and meaningful relationships between predictors and drug use levels among college students. Weighted equations derived from linear discriminant function analyses were generally capable of accurately classifying subject's drug use levels across drug categories and in discriminating single drug use from polydrug use patterns. Typically, the Sensation Seeking Scale entered as the most powerful predictor of substance use and abuse. 相似文献
802.
Relative allocation on concurrent schedules can depend on schedule parameters when behavioral parameters are constant 总被引:1,自引:1,他引:0 下载免费PDF全文
Houston AI McNamara JM Sumida BH 《Journal of the experimental analysis of behavior》1987,47(1):127-131
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior. 相似文献
803.
Little is known about the personal life of John B. Watson, and this interview aims at capturing the personality of the founder of American behaviorism through the eyes of his son, James B. Watson. Today, psychologists and other social scientists increasingly realize that there is an intimate link between the biography of a psychologist and the kind of psychology he or she founds. Thus biographical information about a founding psychologist can help researchers make explicit this essential link. 相似文献
804.
805.
806.
807.
808.
809.
810.
Two hundred and sixty three young adult college students responded to openended questions assessing their specific intentions, motives, and plans for having children. The most commonly stated motives for childbearing reflected a strong interest in establishing an identity and social network. Financial, marital, and emotional stability were identified as important factors influencing the timing of parenthood. Several significant sex differences were found for both motives and the timing of parenthood. These findings are discussed in terms of changing social norms regarding parenthood and changing sex role expectations.Portions of this research were presented at the Eastern Regional Psychological Association Convention in New York, April 1986. This research was funded by a grant from Trenton State College, Committee for Faculty and Institutional Research and Sabbatical Leave. 相似文献