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941.
The purpose of this study was to compare college students' perceptions of the similarity of occupations with the groupings suggested by Roe (1956). Subjects were 90 male and 99 female university freshmen. Four illustrative titles were selected from five of Roe's eight groups. Subjects were asked to judge the similarity of each of the possible pairs of titles. The results were analyzed using multidimensional scaling procedures. The data provide partial support for Roe's postulated structure, although the subject's perceptions were generally more complex than suggested by Roe. In particular, the hypothesized circumplex arrangement of groups received only limited support. 相似文献
942.
Eugene Garcia 《Journal of applied behavior analysis》1974,7(1):137-149
Differential reinforcement and imitation were used with two retarded children to train three sequential verbal responses associated with the display of a picture and questions related to that picture. Each response consisted of a three-word chain in sentence form; combined with verbal responses from the experimenter, this trained sequence formed a short conversational unit. Three experimenters measured the use of each sentence in settings different than the one in which training took place, and with pictures different than those used during training. Two types of generalization sessions were used: (1) General sessions, during which 10 pictures never used during training were displayed to the subject with reinforcement delivered on a noncontingent basis, and (2) Intermixed sessions, during which 10 pictures never used during training were displayed to the subject, but a picture having received training was also displayed, and correct responses to this picture were reinforced on a variable schedule. Both subjects learned the sentences being trained. However, little generalization was evident from this training when all experimenters conducted General probe sessions. Generalization occurred with one experimenter only after that experimenter conducted Intermixed probe sessions. Generalization to a third experimenter was then observed (i.e., after the first two experimenters had conducted Intermixed probe sessions) without the use of Intermixed probe sessions by this third experimenter. 相似文献
943.
Leonard H. Epstein Larry A. Doke Thomas E. Sajwaj Sue Sorrell Betty Rimmer 《Journal of applied behavior analysis》1974,7(3):385-390
The effects and side effects of overcorrection for self-stimulatory behaviors of two children in a specialized day-care program were evaluated. For one child, a “hand” overcorrection procedure involving arm and hand exercises was introduced contingent upon inappropriate hand movements and later contingent upon inappropriate foot movements. After “hand” overcorrection was withdrawn for inappropriate foot movements, a “foot” overcorrection procedure involving foot and leg exercises was introduced contingent upon inappropriate foot movements. For a second child, the “hand” overcorrection procedure was introduced contingent upon inappropriate hand movements during a free-play period, and later contingent upon inappropriate vocalizations at naptime. “Hand” overcorrection was withdrawn and then re-introduced sequentially for both behaviors. Several concurrent behaviors were measured to assess multiple effects of treatment. Results for both children indicated the “hand” overcorrection procedure suppressed inappropriate hand movements and inappropriate behaviors that were topographically dissimilar. In addition, inverse relationships were observed between the second child's inappropriate hand movements and appropriate toy usage during free play and between his inappropriate vocalizations and inappropriate foot movements during naptime. Results suggest that overcorrection procedures that are effective for one behavior can be used to reduce the frequency of topographically different behaviors. This finding is discussed in terms of its practical implications for therapists. 相似文献
944.
According to Hoyt (1974), career education efforts are underway in almost one-third of all school districts in the United States. Indications are that this trend will continue. However, the question of the effects of career education programs remains essentially unanswered. This study was designed to assess the effects of a career education program on students' career maturity as measured by the Career Maturity Inventory (CMI). A pretest/ posttest design was used. The sample consisted of 480 sixth and eighth grade students, one-half of whom participated in a career education program (experimental), with the remaining one-half in a regular school program (control). The career education students consistently displayed higher posttest career maturity levels, four scores being significantly higher. Significant differences were found in occupational knowledge of sixth graders, occupational planning for both the sixth and eighth graders and in the attitude scale score for the eighth graders. It was concluded that the career education program had a positive effect in increasing students' levels of career maturity. 相似文献
945.
946.
Noninstitutionalized retardates and normal children of equal mental age (approximately 8 years) listened to 11 orders of 20 nouns with no instructions to overtly or covertly rehearse. All subjects were in each of three list conditions: (a) when all words were at the same decibel (dB) level, (b) when the 11th item was at a higher dB level, and (c) when the items were repeated at the same dB level using the rehearsal protocol of Rundus (1971). The normals' overall recall was superior to that of the retardates' recall. Repetition of items had no effect on the performance of either group except in the recency portion of the learning curve and on the initial trial for both groups and the fifth trial for the retarded group. The normal group was more susceptible to the yon Restorff effect than was the retarded group. These results were discussed in terms of the changing and different recall strategies of the two groups. 相似文献
947.
Studies have reported that an accessory stimulus in a second modality can have a facilitative effect on sensory detection in a primary modality. However, performance declines when the subject has the additional task of reporting on the accessory stimulus. The facilitative effect has been attributed to an arousal or warning process, while the interference effect has been characterized as a result of limited channel capacity. Auditory sensitivity was assessed under accessory visual stimulation. Visual stimulus intensity (arousal), processing demand, and interstimulus compatibility (same or opposite direction of change of primary and secondary stimuli) were manipulated. The results indicated that interstimulus compatibility, not arousal, accounted for the obtained facilitation effect. Interference due to additional task demands was not observed. It was proposed that the facilitation effect was due to selective sensory encoding. 相似文献
948.
Thomas Brandt Eugene R. Wist Johannes Dichgans 《Attention, perception & psychophysics》1975,17(5):497-503
The dependency of visually induced self-motion sensation upon the density of moving contrasts as well as upon additional stationary contrasts in the foreground or background was investigated. Using two different optokinetic stimuli, a disk rotating in the frontoparallel plane, and the projection of horizontally moving stripes onto a cylindrical screen, it was found that: (1) visually induced self-motion depends upon the density of moving contrasts randomly distributed within the visual field and, with a single contrast area of 1/4 %, is saturated when about 30% of the visual field is moving; (2) additional stationary contrasts inhibit visually induced serf-motion, proportional to their density; and (3) the location in depth of the stationary contrasts has a significant effect upon this inhibition. Their effect is considerable when located in the background of the moving stimuli but weak when appearing in the foreground. It is concluded that dynamic visual spatial orientation relies mainly on information from the seen periphery, both retinal and depth. 相似文献
949.
Ewart A. C. Thomas 《Attention, perception & psychophysics》1975,17(2):158-162
Twenty subjects made all possible (136) pairwise-comparison judgments of pattern goodness between 17 five-dot patterns. Using multidimensional scaling and hierarchical clustering analyses, a two-dimensional representation was judged the most appropriate for the derived pattern space. The interpreted structure of the spatial-hierarchical configuration strongly supported previous findings that pattern redundancy is the most salient dimension underlying pattern goodness judgments and that patterns can be partitioned on this dimension according to the size of their equivalence sets, i.e., the number of patterns resulting from rigid rotations in 90-deg increments or reflection. A psychological mechanism that accounts for the effect of pattern redundancy on judged goodness was proposed. 相似文献
950.
When a visual field is presented for 40 or 80 msec and a subject is asked to judge the duration of the stimulus, judged duration is found to be less when the field is blank than when the field contains three letters, but is the same whether the three letters form a word or not. The perceived difference between “filled” and “blank” fields increases when the subject is required to memorize the presented letters. These data are consistent with a theory which assumes,inter alia, that a stimulus is analyzed by a visual information processor and a timer, that attention is shared between these processors, and that temporal judgments are based on the output of both processors. 相似文献