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871.
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873.
Operant temporal discrimination learning was investigated in goldfish. In the first experiment, there was a fixed daily change in illumination. Eight subjects were trained to operate a lever that reinforced each press with food. The period during which responses were reinforced was then progressively reduced until it was 1 hr in every 24. The final 1-hr feeding schedule was maintained over 4 weeks. The feeding period commenced at the same time each day throughout. The food dispensers were then made inactive, and a period of extinction ensued for 6 days. The pattern of responding suggested that the fish were able to exhibit temporal discrimination in anticipation of feeding time. This pattern of responding persisted for a limited number of days during the extinction procedure. The second experiment produced evidence that operant temporal discrimination could develop under continuous illumination.  相似文献   
874.
Exchange delays and impulsive choice in adult humans.   总被引:4,自引:3,他引:1       下载免费PDF全文
Choice responding by adult humans in a discrete-trial task was examined as a function of conditions that manipulated either the delay to point delivery or the delay between points and their exchange for money. In point-delay conditions, subjects chose between an "impulsive" alternative that provided a small amount of points immediately and a "self-control" alternative that provided a larger amount of points delayed by 15, 30, or 60 s. Points were exchanged for money immediately following the session. Subjects preferred the self-control alternative. In exchange-delay conditions, subjects chose between a small amount of points exchangeable for money immediately following the session and a larger amount of points exchangeable for money after 1 day, 3 weeks, or 6 weeks. A self-control preference observed for all subjects in the 1-day exchange-delay condition reversed to exclusive impulsive preference for 4 of the 6 subjects when choice conditions involved exchange delays of 3 or 6 weeks. These results show that human choice is sensitive to the manipulation of exchange delays and that impulsive preference can be obtained with exchange delays on the order of weeks.  相似文献   
875.
    
In contrast to previous research on apologies, which has examined their role in enhancing impressions of those issuing them (e.g., Darby and Schlenker, 1989), the research reported here draws upon Goffman’s (1955) analysis of the “corrective cycle” and is concerned with constraints associated with the receipt of apologies. Study 1 examines the implications for the actor of accepting, not accepting, or rejecting apologies. It is demonstrated that across a variety of judgments, most positive views of the actor result when apologies are accepted; least positive views are associated with their rejection. A follow-up study sought to establish whether this effect would occur under circumstances in which unconvincing apologies are rejected. Results indicate that the apology’s status (convincing versus unconvincing) has no bearing on perceptions of actors. Based on a hypothetical role-play format, Study 2 addresses the matter of whether actors experience a subjective sense of constraint upon receipt of unsatisfactory apologies. The data suggest that there exists a pronounced tendency to accept such apologies, though typically with conditions that would be specified to the offender. More general implications of the data are discussed.  相似文献   
876.
This paper explores some of the ways in which the environment functions with respect to behavior within an explanatory framework analogous to that of evolutionary biology. In both the behavioral and organic domains, the environment functions differently with respect to individual occurrences and evolutionary units. Within the behavioral domain, the problem of accounting for an occurrence of an operant instance differs from that of accounting for the existence of the operant unit of which the instance is a part. Maintaining these distinctions in levels of analysis within the behavioral domain, we focus first on operant units and operant instances as products of evolutionary processes occurring in the behavioral domain and second upon the causal role of the environment with respect to the existence of operant units and the occurrence of operant instances. The environment's function is selective with respect to origin, maintenance, suppression, and extinction of behavioral populations. At the level of operant instances, the environment has instantiating functions-evocative or alterative. Evocative functions are exemplified by discriminative relations, and alterative functions include both conditional and motivative relations. Implications are considered regarding extension of the analogy to more complex behavior-environment relations.  相似文献   
877.
Compliance with postpartum visits after teenage births in the US was examined among 289 Hispanic teenagers, of whom 127 were born in Mexico or border towns, who delivered at Harris County Hospital District and scheduled postpartum appointments at the Teen Health Clinic. The mean age was 17.31 years for mothers and 21.95 years for fathers. 56.7% (164) were married. 49.8% lived with husbands, 25.8% with parents, 22.3% with friends/relatives, and 2.1% alone. 74.7% stated that they had no social supports. 88.9% had a term delivery, 8.3% a preterm delivery, and 2.8% a fetal loss. 67.5% were first births, 5.5% had a previous abortion, and 3.1% had a previous miscarriage. 23.2% had a previous child, and 0.7% had a previous preterm delivery. Some form of prenatal care was received by 85.1%. 34.3% reported no further educational plans. 17.3% (50) returned for a scheduled postpartum visit. Mothers with a prior history of a premature birth or miscarriage were more likely to return postpartum compared to mothers with a first or prior birth. The differences are marginally significant. None of the mothers with a prior abortion returned. 34.9% of the returning teen mothers were more likely to have had prenatal care. Returning mothers also were a larger percentage of those with no future educational plans. 13.4% of returning mothers had an available social support system. Country of origin was not associated with support systems, prenatal care, return status, educational plans, pregnancy history, or current birth outcome. Out of the 50 returning, 20 were Mexican-born and married. Only Mexican marital status was found to be a significant variable explaining differences. Marital status had no effect on the 26 US native-born returnees. 92% of the Mexican-born teens were married and had a support system. The most dramatic feature of this study is the high level of noncompliance among both US-born and Mexican-born adolescents. There were few distinguishing features between these two groups. Return status was affected by very few features and was achieved by a very small percentage of the study population. The suggestion is made that poverty, a lack of health insurance, and poor knowledge of English, as representative of cultural dissimilarity, may be responsible for poor use of preventive care.  相似文献   
878.
The authors review four new instruments designed to assess multicultural counseling competence in trainees and practicing professionals. The Cross-Cultural Counseling Inventory—Revised (CCCI-R), the Multicultural Counseling Awareness Scale—Form B (MCAS:B), the Multicultural Counseling Inventory (MCI), and the Multicultural Awareness-Knowledge-and Skills Survey (MAKSS) were each critically reviewed in terms of item development, psychometric properties, and pragmatic utility. Specific research suggestions for continued empirical validation on the instruments are posited, and strong cautions regarding their current use in training are leveled.  相似文献   
879.
The authors discuss the role of an academic department in promoting faculty development. Specifically, the authors (a) define faculty development from a departmental perspective, (b) discuss stages and seasons in academic careers, and (c) delineate specific faculty development goals and programs within the department.  相似文献   
880.
Qualitative reviews of the withdrawal literature have reached inconsistent conclusions regarding the strength of the relationship between promotion and turnover. Several issues were addressed in this study which may account for these inconsistencies. First, we differentiate among three distinct operationalizations of promotion: (1) promotion satisfaction; (2) perceptions of promotional opportunity; and (3) actual promotion. We then conduct quantitative reviews using meta-analytic procedures on turnover and the three operationalizations of promotion. We found no significant relationships between promotion satisfaction and turnoveror between perceived promotional opportunities and turnover. However, a significant negative relationship was found between actual promotion and turnover. Theoretical implication of these findings are presented.  相似文献   
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