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921.
Corticosterone, the principal glucocorticoid in the rat, binds selectively to the CA1 pyramidal neurons of the hippocampus where the hormone has been demonstrated to exert a moderate chronic suppression of spontaneous activity. In the first experiment of the current study, the functional behavioral significance of this hormone--brain interaction was investigated in the extinction of an appetitive runway response in normal rats and those with lesions of the hippocampus. During extinction, half of the animals in each group were given daily subcutaneous injections of corticosterone. Whie the classical retardation effect of hippocampal lesions on appetitive extinction was replicated, hormone treatment was without effect in normal or hippocampally damaged subjects. The absence of a hormone effect in normals was primarily attributed to a saturated limited-binding system operating in the normal animal. Experiment 2 tested this notion, repeating the first experiment, with adrenal-ectomized (ADX), ADX + corticosterone replacement, and normal groups of animals. Adrenalectomy produced a striking facilitation of extinction which was speculated to be the result of a hyperactive inhibitory neural organ free from an inhibitory endocrine feedback. Corticosterone treatment normalized the progress of extinction in ADX animals, providing support for the afore-mentioned speculation. In the normal animal, it appears that a stress-induced surge in hormone level interacts with a limited-capacity neural binding to produce a transient dynamic range of behavioral disinhibition, perhaps promoting persistence during initial stages of frustrative nonreward in moderate stress tasks.  相似文献   
922.
Direct biofeedback of blood pressure was compared with frontal EMG biofeedback and with self-instructed relaxation for the treatment of essential hypertension in a controlled group outcome study. Patients were followed up for four months after the end of treatment. Generalization of treatment effects was assessed through pre- and posttreatment measurements of blood pressure under clinical conditions in a physician's office. There were no significant reductions in diastolic blood pressure. The systolic blood pressure (SBP) of the patients receiving blood pressure biofeedback decreased 8.1 mm mercury (p = 0.07) and the SBP of the patients in the relaxation condition decreased 9.5 mm mercury (p = 0.05). In the generalization measures, there were significant reductions in SBP for the relaxation group. The results are discussed in terms of the general lack of replicability within the area of biofeedback treatment of hypertension.  相似文献   
923.
Bilateral medial preoptic-anterior hypothalamic lesions in adult male dogs eliminate or impair copulatory behavior and reduce urine-marking responses but do not affect aggressive behavior. The present study examined the emergence of the adult forms of these same male sociosexual behavioral patterns when the lesions are made prior to puberty. The subjects were allowed to interact with male peers during development. Animals with lesions had reduced frequence of juvenile mounting and an almost total absence of male copulatory activity in adulthood. Urine-marking and aggressive behavior in the juvenile and adult periods were not affected by the lesions. The findings reveal a sparing of function with regard to urine-marking but not sexual behavior.  相似文献   
924.
This study tested the relevance to clinical token economies of the overjustification hypothesis that tangible reward interferes with intrinsic interest in target behaviors and causes such behaviors to be less probable following a period of reinforcement than preceding such a period. The study was carried out in an ongoing token economy for chronic psychiatric patients. Alternated over an 8-week period were weeks of token and no-token reward for one of the program's target behaviors, toothbrushing. Two different amounts of token reward were employed in order to examine whether reward magnitude might influence the presence or extent of overjustification effects. Little evidence was found for the presence of overjustification effects in token economies. However, maintenance of toothbrushing was greater in no-token weeks following weeks of low amounts of token reward than in no-token weeks following weeks of higher amounts of reward. The importance of such complex functional relationships is discussed.  相似文献   
925.
This study investigates the effect some principal characteristics of employment application cover letters have on personnel officers. A sample of personnel executives from 100 major companies was queried as to their perception of the desirability of 12 common cover letter characteristics. The results indicate that the personnel officers do not consistently perceive letters in the manner suggested by the existing literature. Some characteristics are shown to elicit negative responses from personnel officers, and thus should be avoided by job applicants. Several characteristics are strongly preferred by the sample surveyed. The model for an employment cover letter derived from this study should enhance the applicant's chances for a favorable response, or at least prevent letter forms which might detract therefrom.  相似文献   
926.
Conceptual and methodological shortcomings of research on family and interactional psychopathology are owing mainly to the use of vague and ill-defined concepts of communication. Based on a theory of language use and communication within general social and cognitive psychology (e.g., Heider, Mead, Piaget, Rometvet) Blakar has outlined a methodology by which interaction is analyzed in terms of how and to what extent the participants (families) manage or fail to cope with the various prerequisites for successful communication under varying situational conditions. A study illustrating this program is presented: The interaction of twelve families, six with (Group S) and six without (Group N) a schizophrenic member, is analyzed in Blakar's communication conflict situation with respect to the members' ability to decenter and take the perspective of each other. Group S proved significantly more egocentric, their egocentric attitudes resulting, as would be expected, in very inefficient communication. Moreover, Group S were not able to adapt their pattern of communication to the changing situational requirements. Finally, the subtle interplay between the capacities and behavior of the individual members and the family system is illustrated: the egocentrism of the members resulted in "closed systems," and the closed systems hindered adequate feedback, forcing the members to decenter.  相似文献   
927.
928.
Several social and research issues directly affected the development and implementation of multivariate assessment in a large community-based applied research program. Examples are drawn from experiences of the Preparation through Responsive Educational Programs Project for disruptive and skill deficient adolescents in suburban, rural, and urban junior high school settings, focusing on the assessment of academic and social skill development and long-term skill maintenance. The social context altered both project treatment and follow-up plans, requiring assessment of potentially unintended effects and decreasing consistency across sites. Future community acceptance of such programs may depend on the investigators' adaptation to diverse community pressures for program conduct and assessment and the measurement of phenomena that are not always directly observable.  相似文献   
929.
930.
A conception of locus of control attribution was advanced as an alternative to the generalized expectancy view presented by Rotter. That alternative stems from regarding the individual as actively constructing a pattern of specific choice consequence relations out of his/her ongoing experience. An integration of structural and factor approaches was used to analyze the Rotter I-E scale. The structural analysis categorized items on four dimensions (focus, area, self-attribution and world attribution) and indicated that the I-E scale unevenly represents the domain it encompasses. Nevertheless, specification of that structural matrix helps to provide a more comprehensive framework for interpreting I-E response patterns of 216 high school juniors and seniors. For example, male responses cohered around asserting active control over tasks hut attributing control to external sources with regard both to personal issues and to more abstract systems-related issues. Females organized their senses of self-efficacy with a central theme being that of a passive agent stance, plus an expectation that circumstances would provide equality of opportunities to which they could respond. Thus the present approach has demonstrated its utility in interpreting I-E findings and its conceptual advantage for personality research on locus of control and on similiar attributional characteristics.  相似文献   
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