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41.
The importance of using culturally sensitive educational materials in HIV-related interventions with racial and ethnic minority groups is widely recognized. However, little empirical research has been conducted to assess the relative effectiveness of different techniques for creating culturally sensitive AIDS educational videos. Two field experiments with three samples of African American adults (N = 174, 173, and 143) were conducted to assess how source characteristics (race of communicator), message characteristics (multicultural message vs. culturally specific message), and audience characteristics (racial distrust and AIDS-related distrust) influence proximate (perceptions of the message's credibility and attractiveness) and distal (AIDS-related attitudes, beliefs, and behavioral intentions) output variables for AIDS educational videos. In Study 1, an AIDS video with a culturally specific message was rated as more credible, more attractive, and of higher quality than was a video with a multicultural message. The multicultural message was rated less favorably when delivered by a White announcer than when the announcer was Black. In Study 2, the same pattern was replicated with a second community sample and a campus-based sample. Study 2 also indicated that a multicultural message might be more effective if delivered in a culturally specific context, namely, after audience members watch a culturally specific video. Minimal changes were observed in distal outcome variables. It is argued that influencing proximate output variables is necessary, though not sufficient, for effecting long-term change in AIDS-related attitudes, beliefs, and behaviors.  相似文献   
42.
In this study it was determined whether (a) classification as opposed to absence of classification has an effect on the quality of clinical hypotheses (b) the DSM-III-R and the CBCL have a different effect on the quality of clinical hypotheses, and (c) the potential difference between the DSM-III-R and the CBCL is moderated by the different number of syndromes identified by these systems. To investigate these questions, an experiment was conducted in which 86 clinicians generated hypotheses for six cases. The clinicians were divided into a DSM-III-R, a CBCL, and a control group. Of the six cases, two were classified by both classification systems as one syndrome, two were classified as one syndrome by the DSM-III-R but as two syndromes by the CBCL, and two were classified as two syndromes by the DSM-III-R but as one syndrome by the CBCL. The quality of the hypotheses was determined by means of four dependent variables selected from an overview of qualitative criteria: explanatory value, redundancy, possibility of operationalization, and specificity. No differences between the CBCL and the control groups were found. The DSM group performed better than the control group regarding explanatory value and redundancy. The DSM-III-R group also scored better than the CBCL group regarding explanatory value, particularly when the number of identified syndromes was two for the CBCL and one for the DSM-III-R.  相似文献   
43.
The relation between substance use and violent behavior in adolescence is reviewed, and each of five competing models of this relation is examined. I begin by presenting background material on adolescent substance use and adolescent violence. I then describe five different models that have been proposed to explain the association between substance use and violent behavior. Next, I review the adolescent literature concerning substance use and violence, noting methodological weaknesses that have plagued this research. I conclude with an evaluation of the five models and suggestions for future research.  相似文献   
44.
When variations in imagery ability are used to predict task performance, distinct and consistent relationships do not tend to emerge. A selective review of studies is undertaken to outline some basic reasons why individual difference measures of imagery are often so unsuccessful. Relevant studies concerning the learning and performance of motor skills are examined in some detail. It is concluded that the major problem in these studies is the types of imagery tests that have been employed; these tests have not adequately measured imagery ability. A recently developed instrument, the Movement Imagery Questionnaire, which has been designed to assess individual differences in visual and kinesthetic imagery of movement is discussed.  相似文献   
45.
Most of the distance models underlying multidimensional scaling assume that if a stimulus y is between the stimuli x and z on each dimension, then x and z should be the farthest apart of the three stimuli. An iterative algorithm is described that uses only this betweenness prediction to infer the ordering of a set of stimuli on each of one or two dimensions. Applied to previously published semantic similarity data, this algorithm produced two-dimensional configurations that were similar in appearance to Euclidean configurations but generally involved fewer violations of the betweenness prediction.  相似文献   
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Most phonological investigations of aphasic speech have focused on consonants. In this study, the vowel substitutions of five English-speaking Broca's aphasics were investigated with respect to several major explanatory hypotheses. An important possible motivating factor for aphasic substitutions, phonological environment, is an unlikely origin for these errors, since most substitutions occur along the paradigmatic axis. Another prominent hypothesis, markedness, also has no predictive power for the data of this sample. However, an analysis of the five Chomsky and Halle (1968, (The Sound Pattern of English), New York: Harper and Row) vowel features indicates that the two features for vowel height are selectively impaired: There is a strong tendency for lower vowels to replace higher targets. Moreover, the substitution sounds tend to be close to their target sounds along the height axis. Four possible hypotheses are advanced to account for this consistent lowering tendency.  相似文献   
48.
The major purpose of the present investigation was to examine the combined influence of variations in foreperiod length (1.0, 5.0 sec) and catch trial frequency (0.0, 0.1, 0.2) on simple reaction time (RT) magnitude when verbal mediation was permitted and when it was not. A significant foreperiod length, catch trial frequency, mediation type interaction was obtained supporting the notion that all three factors influence a common process (i.e. Sternberg 1969), here called ‘preparation’. More specifically, for the non-mediation group, foreperiod length and catch trial frequency had both additive (0.0 vs 0.1) and interactive (0.1 vs 0.2) effects on mean simple RT while only catch trial frequency significantly altered simple RT for the mediating group. In all instances, mean simple RT increased significantly when some catch trials were employed as opposed to when none were used, a finding which was interpreted as reflecting an induced preparation decrement upon the introduction of catch trials.  相似文献   
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Three experiments employing the McCollough paradigm were conducted to determine the spatial-frequency content of visual imagery. In Experiment 1, large and reliable pattern-contingent color aftereffects were obtained after adaptation to visual imagery. The direction of the aftereffects indicated that subjects were adapting to higher spatial frequencies in their imagery. These results contrast with the data of Experiment 2, which demonstrate that color aftereffects obtained with adaptation to physically present stimuli are mediated by the fundamental spatial frequency components. The magnitude of the imagery-induced aftereffects in Experiment 1 equaled the magnitude of the externally induced aftereffects obtained in Experiment 2 with the same subjects. By blurring the to-be-imaged patterns (Experiment 3), the fundamental Fourier components became the salient perceptual features of the stimuli, and the direction of the imagery-induced aftereffects was reversed from that of Experiment 1, indicating that the spatial frequency content of the imagery had changed from higher to lower frequencies. Under normal viewing conditions, subjects use the higher spatial frequencies associated with the perceptually salient edges of stimuli to construct their images. The results of Experiments 1 and 3 are discussed in light of a current controversy over the nature of information representation in imagery, and it is concluded that support has been obtained for the analog model of visual imagery.  相似文献   
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