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861.
Hooded rats were given conditioned inhibition training in which the taste of saccharin alone was always followed by induced illness, but the taste of saccharin plus the odor of amyl acetate was not. In a series of three subsequent tests—summation, enhancement of conditioning, and retardation—it was demonstrated that the odor had acquired active inhibitory properties. The results paralleled those obtained with more traditionally studied stimuli and techniques and hence were found to be readily predictable from a recent model of conditioning set forth by Rescorla and Wagner (1972).  相似文献   
862.
This study is another contribution to the development of a satisfactory child version of the linguistic task of judging grammaticality. With a nondifferentially reinforced forced-choice procedure, it was found that responses of 24 5- and 24 7-yr-old children did vary as a function of the grammatical complexity of stimulus sentences. The children judged sentence stimuli of two types (negatives and wh-word questions) each having three levels of grammatical complexity (two primitive and one well-formed). After each stimulus presentation, the subject pointed to the adult or the child in a photograph, depending on who was judged to have produced that utterance. Performance of the two age groups did not differ for the question stimuli, for which subjects pointed to the adult more frequently as the grammatical complexity of wh-word questions increased. In response to the negative sentences, the older group attributed more well-formed stimuli to the adult than primitive ones. While the younger group pointed to the adult more frequently for well-formed negatives than for the middle level negatives, they made more adult responses than expected to the least complex negatives. It was concluded that, with this procedure, 5- and 7-yr-olds demonstrate ability to distinguish grammatically well-formed from primitive sentences. Procedural improvements for future research may allow children this age and younger to demonstrate more adult-like discrimination between a variety of primitive and well-formed sentences.  相似文献   
863.
The ability of preschool children to construct and reconstruct ordered sequences was examined in a series of four experiments. In Expt. 1, the task was to copy, with the model present or absent, the order of items pegged on a clothesline. In Expts. 2–4, the subjects were required to reconstruct ordered series of pictures from memory. In all experiments, the orders were either logical or arbitrary. Reconstruction of an arbitrary series of events is within the problem solving capacity of 4-yr-old children if (a) reconstruction takes place in the presence of the model or follows immediately upon the removal of the model and (b) the original sequence is presented simultaneously. If, however, the lag between viewing and reconstruction is increased and/or the original set is not viewed simultaneously, as a unit, performance declines. The provision of an inherent order to the items within a set, either by introducing a connective narrative, or a depicted logical sequence, is sufficient to maintain that order over time and to provide a unifying cohesion to the items when viewed successively.  相似文献   
864.
Contradictory results have been reported on the effectiveness of various reinforcers with children of different ages and socioeconomic classes. The present study considered the relative effectiveness of two types of verbal and one type of tangible reinforcement on a two-choice discrimination task (marble-in-the-hole) for preschool children. IQ and operant level were treated as covariates and accounted for the observed differences in performance between the 24 middle-class and 24 lower-class children and between the 24 males and 24 females. Disparate findings of previous studies regarding sex and social class differences might have been reconciled if baseline and IQ had been considered.  相似文献   
865.
Children and adults quantified random patterns of dots, under unlimited exposure duration. For adults and children two distinct processes appear to operate. For adults the quantification of collections of from one to three dots is essentially errorless, and proceeds at the rate of 46 msec per item, while the quantification rate for from 4 to 10 dots is 307 msec per dot. For children the same operating ranges appear to hold, however children are much slower. The lower slope is 195 msec per dot, while the upper is 1049. Although the results for adults and children are similar except for the overall rates, the nature of the isomorphism between children and adults is unclear.  相似文献   
866.
In two oddity learning studies with children, subjects were reinforced for oddity (or nonoddity) responding on line-tilt or dot numerosity problems. Interposed form and color problems were not reinforced. No instructions to make oddity choices were given. In Experiment I it was found that reinforcement for oddity or nonoddity responding on tilt and numerosity problems produced the corresponding tendency toward oddity or nonoddity performance on these problems and also on the nonreinforced form and color problems. These results show a generalized oddity phenomenon similar to generalized imitation. In Experiment II a third type of nonreinforced problem was presented in this same format: compound stimuli permitting either a color or a form solution. It was found that immediate prior training with nonreinforced form problems, interpolated among the reinforced tilt and numerosity problems, led to form-oddity choices in the compound problems. Similarily, color pretraining produced color-oddity choices. These results show that selective discriminative stimulus control can be obtained in oddity learning, without reinforcement for choices on either of the two dimensions involved.  相似文献   
867.
144 Subjects divided into four-person groups participated in three discussions. In each group, one member (Target subject) was preselected as either being high or low in cognitive complexity. The groups were then assigned to one of three conditions. Under Continuous Reinforcement the Target subject received a reinforcing light cue following each verbalization in the second of three discussions (no light cues used in the first and third discussions). Target subjects under Partial Reinforcement received light cues on a 50% variable ratio reinforcement schedule. Control subjects received no light cues in any session. Target subjects in both experimental groups showed conditioning effects on all dependent measures. While no differences were found between reinforcement conditions, results suggest that abstract subjects are able to make more use of feedback cues than concrete subjects.  相似文献   
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