全文获取类型
收费全文 | 54841篇 |
免费 | 1936篇 |
国内免费 | 27篇 |
专业分类
56804篇 |
出版年
2020年 | 502篇 |
2019年 | 634篇 |
2018年 | 829篇 |
2017年 | 923篇 |
2016年 | 914篇 |
2015年 | 710篇 |
2014年 | 780篇 |
2013年 | 4102篇 |
2012年 | 1433篇 |
2011年 | 1544篇 |
2010年 | 1006篇 |
2009年 | 1003篇 |
2008年 | 1429篇 |
2007年 | 1318篇 |
2006年 | 1196篇 |
2005年 | 1081篇 |
2004年 | 1004篇 |
2003年 | 1048篇 |
2002年 | 1026篇 |
2001年 | 1756篇 |
2000年 | 1712篇 |
1999年 | 1229篇 |
1998年 | 592篇 |
1997年 | 515篇 |
1992年 | 1120篇 |
1991年 | 1078篇 |
1990年 | 1053篇 |
1989年 | 1003篇 |
1988年 | 936篇 |
1987年 | 940篇 |
1986年 | 924篇 |
1985年 | 1028篇 |
1984年 | 849篇 |
1983年 | 710篇 |
1982年 | 541篇 |
1981年 | 590篇 |
1979年 | 851篇 |
1978年 | 640篇 |
1977年 | 588篇 |
1976年 | 550篇 |
1975年 | 769篇 |
1974年 | 832篇 |
1973年 | 910篇 |
1972年 | 746篇 |
1971年 | 685篇 |
1970年 | 652篇 |
1969年 | 695篇 |
1968年 | 826篇 |
1967年 | 764篇 |
1966年 | 787篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
981.
The study investigated possible sex differences in the types of problems that are correlated with Beck Depression Inventory (BDI) scores, using a sample of college students. Problems related to assertiveness and feeling ill at ease were positively correlated with BDI scores for males, but not for females. In contrast, conflicts with parents, feelings of being boxed in and of boredom, lack of money, and chronic physical complaints were positively related to BDI scores for females, but not for males. 相似文献
982.
Claudia Card Jacquelynne S. Eccles Adrienne L. Zihlman Mary Lou Wylie 《Sex roles》1984,10(9-10):837-843
983.
P M Greenfield E S Savage-Rumbaugh 《Journal of comparative psychology (Washington, D.C. : 1983)》1984,98(2):201-218
Analysis of two chimpanzees' conversations with their teacher during a tool-use training task demonstrated that chimps use lexigrams, a humanly devised visual symbol system, selectively to encode perceived variability; that is, they generally used their symbols to differentiate alternative possibilities or to represent change or novelty in a situation. In contrast, they tended to leave unsaid what was unchanging, repetitive, or the unique possibility in a situation. Perceived variability influenced not only which symbols were selected but also utterance length: A single dimension of variability in a situation leads to single-lexigram utterances; multiple dimensions are associated with multi-lexigram utterances. This pattern of results indicates that the absence of formal grammatical structure in chimp language does not imply that utterances beyond one word in length are either rote strings or imitations. The chimps' tendency to mention the variable while leaving the constant or redundant unsaid is, moreover, strong support for the position that their use of a humanly devised symbol system is more than a series of conditioned responses. 相似文献
984.
985.
986.
Bonnie B. Vermilyea David H. Barlow Gerald T. O'Brien 《Journal of psychopathology and behavioral assessment》1984,6(1):1-11
One purpose of this investigation was to examine the importance of assessing treatment integrity in a study evaluating a treatment for specific anxiety disorders. Three subjects, two social phobics and one simple phobic, received self-instruction training (Phase I) followed by exposure and self-instruction training (Phase II) in a multiple baseline across subjects design. All subjects were assessed during a pretreatment baseline and throughout treatment using measures of treatment integrity and measures of change in phobic severity. Improvement took place at different times for different subjects. Measures of treatment integrity, which consisted of monitoring of self-statements as well as practice outside the session, indicated that treatment was not always received as intended and that improvement was correlated with practice. The usefulness of measures of treatment integrity in both clinical and research settings is highlighted. 相似文献
987.
Three experiments investigating the effects of arousal on the T-maze choice behavior of inbred mouse strains are reported. In Experiment 1, CBA and NZB mice were administered unrewarded free choice alternation tests on 10 consecutive days under either No Shock, Shock Start (shocked in the start box), or Shock Choice (shocked at the choice point) treatment conditions. Both strain and treatment effects were observed: In the No-Shock condition, the nonreactive CBA strain alternated, but the reactive NZB strain did not. In the Shock Start condition the CBA strain showed only a suppressed alternation, while the NZB strain administered the same treatment perseverated. Both strains perseverated in the Shock Choice condition. In Experiment 2, NZB mice administered identical shocks in the start box and goal arms on both trials of five consecutive tests conducted once a day perseverated to the same goal arm in which they had been shocked on the first trial. In Experiment 3, NZB mice punished for perseverating (with shock continuation) and simultaneously reinforced for alternating (with shock termination) showed a “punishment paradox”; they perseverated despite the reinforcement contingencies. These results, which are congruent with the optimal arousal theory and several characteristics the theory shares with the emergent neophobia construct, support the contention that arousal mediates a symmetrical relationship between approach and avoidance along a novelty-familiarity continuum. 相似文献
988.
989.
990.
Kinetic subjective contours 总被引:2,自引:0,他引:2