全文获取类型
收费全文 | 52661篇 |
免费 | 1983篇 |
国内免费 | 17篇 |
专业分类
54661篇 |
出版年
2020年 | 486篇 |
2019年 | 617篇 |
2018年 | 849篇 |
2017年 | 907篇 |
2016年 | 908篇 |
2015年 | 617篇 |
2014年 | 800篇 |
2013年 | 3873篇 |
2012年 | 1499篇 |
2011年 | 1619篇 |
2010年 | 971篇 |
2009年 | 962篇 |
2008年 | 1401篇 |
2007年 | 1369篇 |
2006年 | 1277篇 |
2005年 | 1139篇 |
2004年 | 1119篇 |
2003年 | 1025篇 |
2002年 | 1104篇 |
2001年 | 1630篇 |
2000年 | 1559篇 |
1999年 | 1171篇 |
1998年 | 612篇 |
1997年 | 501篇 |
1992年 | 956篇 |
1991年 | 901篇 |
1990年 | 923篇 |
1989年 | 906篇 |
1988年 | 874篇 |
1987年 | 849篇 |
1986年 | 878篇 |
1985年 | 944篇 |
1984年 | 754篇 |
1983年 | 698篇 |
1982年 | 575篇 |
1981年 | 525篇 |
1979年 | 873篇 |
1978年 | 628篇 |
1977年 | 543篇 |
1976年 | 554篇 |
1975年 | 742篇 |
1974年 | 820篇 |
1973年 | 820篇 |
1972年 | 705篇 |
1971年 | 634篇 |
1970年 | 609篇 |
1969年 | 691篇 |
1968年 | 807篇 |
1967年 | 714篇 |
1966年 | 719篇 |
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
941.
James M. Malott Russell E. Glasgow H. Katherine O'Neill Robert C. Klesges 《Journal of applied behavior analysis》1984,17(4):485-495
We evaluated the effects of adding a social support component to a worksite controlled smoking treatment program. Twenty-four participants were randomly assigned to either a controlled smoking or a controlled smoking plus partner support condition. Within a multiple baseline across behaviors design, smokers in both conditions made efforts to achieve sequential 50% reductions in: (a) nicotine content of brand smoked, (b) number of cigarettes smoked per day, and (c) percentage of each cigarette smoked. Self-monitoring records, laboratory analyses of spent cigarette butts, and carbon monoxide determinations indicated that both conditions were effective in producing significant reductions in each of the three target behaviors and in carbon monoxide levels. All participants who quit smoking during the program maintained their abstinence at a 6-month follow-up, and those who did not quit were smoking less at follow-up than they had at pretest on all dependent variables. However, few differences were observed between controlled smoking and controlled smoking plus partner support conditions either during treatment or at the 6-month follow-up. Results are discussed with regard to previous worksite studies, future directions for research on social support, and variables that may have mediated treatment outcome. 相似文献
942.
We investigated the programming of generalization and maintenance of correspondence between verbal and nonverbal behavior in a preschool setting. Four children participated in a series of multiple-baseline designs. In Experiment 1, delayed reinforcement of verbal behavior effectively controlled maintenance of correspondence with previously trained responses and also resulted in generalization of correspondence to one untrained response. As the latter effect was limited, Experiment 2 was a further assessment of the effects of delayed reinforcement of generalization of correspondence to untrained responses, and consistent generalization was shown. Experiment 2 also showed that generalization, if lost, could be recovered through use of "booster training," in which the original contingencies were reinstated for a brief period. Experiment 3 provided replications, with two additional children, of the effects of delayed reinforcement on maintenance of correspondence. Results are discussed in terms of using delayed reinforcement as an indiscriminable contingency. 相似文献
943.
Bennett I. Bertenthal Dennis R. Proffitt James E. Cutting 《Journal of experimental child psychology》1984,37(2):213-230
Two experiments assessed infant sensitivity to figural coherence in point-light displays moving as if attached to the major joints of a walking person. Experiment 1 tested whether 3- and 5-month-old infants could discriminate between upright and inverted versions of the walker in both moving and static displays. Using an infant-control habituation paradigm, it was found that both ages discriminated the moving but not the static displays. Experiment 2 was designed to clarify whether or not structural invariants were extracted from these displays. The results revealed that (1) moving point-light displays with equivalent motions but different topographic relations were discriminated while (2) static versions were not, and (3) arrays that varied in the amount of motion present in different portions of the display were also not discriminated. These results are interpreted as indicating that young infants are sensitive to figural coherence in displays of biomechanical motion. 相似文献
944.
Carl E Granrud Albert Yonas Linda Pettersen 《Journal of experimental child psychology》1984,38(1):19-32
Monocular depth perception was compared with binocular depth perception in 5- and 7-month-old infants. Reaching was used as the dependent measure. Two objects, identical except in size, were presented simultaneously to each infant. The smaller object was within reach for the infants while the larger object was just beyond reach. The two objects subtended equal visual angles from the infants' observation point. With binocular presentation, 96% of the 7-month-olds' reaches and 89% of the 5-month-olds' reaches were for the nearer object. With monocular presentation, 58% of the 7-month-olds' reaches and 65% of the 5-month-olds' reaches were for the nearer object. The reaching preferences observed in the monocular condition indicated sensitivity to monocular depth information (motion parallax, accommodation, and relative size information were available). Binocular viewing, however, resulted in a far more consistent tendency to reach for the nearer object. This result suggests that the infants' perception of the objects' distances was more veridical in the binocular condition than in the monocular condition. 相似文献
945.
This research had two aims. The first was to test three explanations of performance on N-term series tasks by young children: the labeling model of B.DeBoysson-Bardies and K. O'Regan (1973), Nature (London), 246, 531–534, the sequential-contiguity model of L. Breslow (1981, Psychological Bulletin, 89, 325–351), and the ordered array or image model of C. A. Riley and T. Trabasso (1974, Journal of Experimental Child Psychology, 17, 187–202). In the first experiment, 5-year-old children were taught additional premises which would interfere with labeling and sequential-contiguity processes, but not with forming an ordered array. Reasoning performance was essentially comparable to previous results with the paradigm, thus supporting the ordered array model. The second aim was to reexamine children's ability to learn sets of premises which can be assembled into an ordered array, since there was reason to believe that previous studies had created false positives. In the second experiment, 3- to 7-year-old children were taught either overlapping (a > b, b > c, …) or nonoverlapping (a > b, c > d, …) premises. Overlapping premises can be integrated into an ordered array (a, b, c, d, e), but nonoverlapping premises cannot. However, the overlapping condition proved more difficult, and the success rate for preschoolers () was of zero order. This raises doubts about their ability to learn a set of premises of the kind required for transitive inference. These doubts were strengthened by the third experiment which showed that when premises were not presented in serial order, preschool () children could not learn the premises of an N-term series task. 相似文献
946.
Correlations were computed between United States per capita consumption of cigarettes and 41 different foods for the years 1964–1977 and 1968–1973. There were significant negative correlations between consumption of cigarettes and sugar. Few other foods showed any relationship to cigarette consumption. These findings corroborate the results of a recent human laboratory study of cigarette smoking and food consumption and a recent animal study of the effects of nicotine on food consumption, taste preferences, and body weight. Taken together, these studies suggest that the inverse relationship between cigarette smoking and body weight may be partially explained by changes in consumption of sweet-tasting high caloric foods. 相似文献
947.
Nursery schoolers and first- and third-graders participated in an interview which assessed recall, comprehension, and perceived importance of three sources of self-knowledge: social feedback, self-observation, and social comparison. For recall measures, these sources were embedded in stories about a child making a self-discovery. Recall of all three sources improved with grade level, and feedback was the best remembered self-validational process. Comprehension was defined as the ability to identify the sources as depicted in line drawings, and it, too, increased with grade level. All three sources were well understood by older children, but preschoolers had difficulty with the concept of social comparison. Ratings of importance, also assessed using line drawings, were independent of grade level. When selecting their own “very best” source of self-knowledge, children cited self-observation most frequently. A supplementary sample of preschoolers nominated the best source of self-knowledge for other children rather than for themselves; under these instructions, feedback from others emerged as the preferred source. 相似文献
948.
The purpose of the present study was to investigate the influence of race (black, white) on the MMPI performance of alcoholic and nonalcoholic inpatients. Subjects were 73 (27 black, 46 white) male alcoholic inpatients and 73 (27 black, 46 white) male nonalcoholic psychiatric inpatients. While black and white alcoholics failed to differ on the MMPI, white alcoholics presented as less disturbed and black alcoholics as less defensive and distressed, compared to their respective nonalcoholic counterparts. Furthermore, only white alcoholics were accurately identified by the MMPI 2-4/4-2 high-point pair combination and only white alcoholics achieved more high-point pairs containing Scale 4 relative to nonalcoholic controls. 相似文献
949.
R E Reichlin 《Journal of personality assessment》1984,48(1):71-81
Review of empirical studies of Rorschach performance by older adults (age 65+) indicates that previous research findings of declining cognitive flexibility and impoverishment of personality may be artifacts of design methodologies that have failed to adequately account for biosocial-psychological differences between age groups and within the older age group itself. When findings are assessed in terms of variables reflective of age cohort as well as residential status, diagnosis, health status, and test-taking attitude, important data become available. Suggestions concerning test interpretation are offered in lieu of the current lack of age matched base rates for Rorschach scoring variables. 相似文献
950.