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301.
Twenty undergraduate students were exposed to single response-independent schedules of reinforcer presentation, fixed-time or variable-time, each with values of 30 and 60 s. The reinforcer was a point on a counter accompanied by a red lamp and a brief buzzer. Three color signals were presented, without consistent relation to reinforcer or to the subjects' behavior. Three large levers were available, but the subjects were not asked to perform any particular behavior. Three of the 20 subjects developed persistent superstitious behavior. One engaged in a pattern of lever-pulling responses that consisted of long pulls after a few short pulls; the second touched many things in the experimental booth; the third showed biased responding called sensory superstition. However, most subjects did not show consistent superstitious behavior. Reinforcers can operate effectively on human behavior even in the absence of a response-reinforcer contingency and can, in some cases, shape stable superstitious patterns. However, superstitious behavior is not a consistent outcome of exposure of human subjects to response-independent reinforcer deliveries.  相似文献   
302.
Two cynomolgous macaques categorized six colors into two groups of three after conditional discrimination training (zero-delay symbolic match-to-sample). The procedures resulted in the establishment of relations among the elements of each set-relations that were not specifically trained and that can be characterized by the properties of reflexivity, symmetry, and transitivity. Each set of colors was related to a characteristic pattern of responding: One response pattern involved temporal duration (press and hold the response keys); the second response pattern entailed repeated pressing and releasing of the response keys (fixed ratio 8). Six combinations of two colors were trained, three combinations from each set. After discriminative performance stabilized for each monkey, they were tested with 10 additional color combinations, all of which differed from the training combinations. The conditional relations established between test combinations can be characterized as stimulus equivalence. The training procedures were analogous to the procedure of using category names, and have implications for understanding the function of language in the formation of equivalence classes.  相似文献   
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The past fifteen years, in particular, have seen a major increase in the extent to which both adolescents and young adults are engaging in sexual intercourse. While several studies call attention to the increasing incidence among college/university students, the concomitant shifts in the sociopsychological realms of sexuality are also important dimensions which impact upon sexual concerns of youth. Hence, the purposes of this study are to examine the behaviors, attitudes, and concerns of students who have engaged in coitus, as well as any changes they seek in their sex lives. The sample consisted of 123 never-married male and 205 never-married female undergraduate students from a state university. The data were obtained by utilizing an anonymous questionnaire administered to volunteers during regular university classes. Among the coitally active, 67.4% of males were psychologically satisfied after their first sexual experience, but only 28.3% of females. In contrast, 80.9% of males and 28.3% of females reported current psychological satisfaction with their sexual experiences. Significant differences between genders focused on male dissatisfaction with infrequent opportunities for sexual intercourse, lack of variety of sex partners, and insufficient oral-genital stimulation, whereas females expressed concerns relating to lack of stimulation to their breasts, painful sexual intercourse, lack of orgasm during sexual intercourse, and feelings of guilt and fear. An increasing awareness of current sexual behaviors, attitudes, and concerns of university students can help family life educators to meet student needs as they react to changes in interpersonal relationships, families, and society.  相似文献   
309.
The eating disorders of anorexia nervosa and bulimia are increasing in frequency among adolescent females. These increases have been linked to the cultural ideal in American society of thinness. Attempting to control weight is one behavioral manifestation of the desire for thinness. One particular group of adolescents, female cheerleaders, often experience pressure to attain and maintain weight that is lower than other adolescents of the same height. This study examined cheerleaders' desire for thinness in relationship to disordered eating and weight control behaviors. A Desire for Thinness Scale and selected scales from three eating disorders instruments were administered to 751 high school cheerleaders from the Midwest. Cheerleaders who scored in the upper third on the Desire for Thinness Scale were compared with those who scored in the lower third. Cheerleaders who expressed a strong desire for thinness had significantly higher scores (p less than .0001) on 7 of 8 eating disorders scales. The greater the desire for thinness, the more likely the tendency to report disordered eating and weight control behaviors associated with bulimia. Implications from this study include an awareness of how a cultural ideal of thinness may indirectly increase disordered eating and weight control behaviors by making weight loss a salient goal. A proactive approach to modifying negative aspects of the cultural emphasis on thinness is proposed.  相似文献   
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Factors related to eating disorders in young adolescent girls   总被引:1,自引:0,他引:1  
The objective of this study was to identify factors related to eating disorders in young adolescent girls. Three hundred eighty-five girls who were attending a career conference at a midwestern university completed the Eating Disorder Instrument (EDI) along with a biographical data sheet. The EDI is designed for the assessment of psychological and behavior traits common in eating disorders. While 81% of the young subjects were assessed to be within the range for ideal weight or were underweight, 78% preferred to weigh less. Only 14% were satisfied with their current weight. Findings for each of the subscales used revealed significant differences among the girls based on intact versus broken family; subjects' actual and preferred weight; whether the family ate meals together; average grades; age and grade in school; fathers' occupation; future career plans; place of residence; and feelings toward their mothers.  相似文献   
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