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191.
Piaget attributes perseverative error in infant manual search to the failure of the infant to conceive of objects as permanent entities which retain their identity when hidden at successive locations A and B. An experiment was performed to test this explanation in which search was compared under three conditions: when the object was hidden at A and B, when the object was covered but visible at A and B, and when the object was visible and uncovered at A and B. Errors occurred under all three conditions taking the form of a conflict in which infants searched persistently either at A or at B. The conflict was at a maximum when the object was hidden, but was evident even when the object was visible but covered. It is suggested that errors may reflect lack of coordination between egocentric and visual frames of reference in relation to which the object is located.  相似文献   
192.
A program was designed to teach coin equivalence to mentally retarded adolescents. Coin equivalence was defined as choosing several different combinations of coins to equal specified target values. A pretest-posttest matched-groups design was employed with an experimental group receiving the monetary training, and a no-training control group. A multiple baseline across coin-counting responses was also incorporated in the experimental group. Training was divided into six stages, each teaching one specific method of combining coins to equal 10 target values from 5¢ through 50¢. A three-component response chain was used, requiring (a) naming, (b) selecting and counting, and (c) depositing target monetary values into a coin machine. Experimental subjects improved significantly in coin equivalence performance and maintained their skill on follow up tests; control subjects did not.  相似文献   
193.
The purpose of the present study was to test the validity of three hypotheses previously offered to explain the attenuating effects of pacifistic noncooperation on instigative aggression. During part one of the experiment all subjects served as instigators; in the second part they actually set shocks for the target. Subjects instigated either a cooperative or noncooperative confederate, and either did or did not have veto power over the confederate's shock selections. Results of the study indicated that all hypotheses, norm-conformity, compliance, and maintenance of power, were viable for subgroups of subjects. Results were discussed in terms of individual differences and the temporarily inhibiting effects of passive resistance.  相似文献   
194.
Masculine and feminine subgroups of males and females were selected from samples of high school and college students on the basis of composite scores from several M—F scales. They were compared on intelligence as measured by a verbal test, Terman's Concept Mastery Test, and a nonverbal test, D-48. Results did not support previous findings of sex differences in intelligence but showed that masculine subgroups of both sexes scored higher of the nonverbal test.  相似文献   
195.
It was hypothesized that if a behavior is freely engaged in with the expectancy that an aversive consequence will follow, the intrinsic motivation to perform that behavior will increase when the aversive consequence is no longer present. Subjects either worked on a list of anagrams while receiving electric shock on a VR schedule, while being threatened by electric shock, or in the absence of shock. The experimenter then left the subject alone for 10 minutes with a new list of anagrams. Subjects in the shock condition solved more anagrams on the posttest than subjects in the threat-of-shock and noshock conditions. Subjects in both the shock condition and the threat-of-shock condition reported that they spent more of their free time on the anagrams than subjects in the no-shock condition.  相似文献   
196.
Psychophysical thresholds for the detection of sinusoidal vibration of the thenar eminence of the hand were determined for children and adults. The subjects in the child group were between 8 and 11 years old, and the adults were between 20 and 39 years old. Measurements were made for vibration frequencies ranging from 18 to 700 Hz and stimulus durations ranging from 28 to 1,000 msec. For both children and adults, thresholds were a Il-shaped function of stimulus frequency. However, the exact form of the function was influenced by the age of the subjects. At frequencies above 200 Hz, thresholds were virtually identical for children and adults, but below this frequency children were more sensitive than adults. This finding, in combination with known changes in the anatomy of the Pacinian corpuscle with age, is in agreement with a filter model of this cutaneous receptor. Furthermore, variation of stimulus duration resulted in data in agreement with the theory that two classes of mechanoreceptors, Pacinian and non-Pacinian, mediate the perception of vibration.  相似文献   
197.
198.
The syllabic structure and phonemic inventory of one child were analyzed at the beginning of word production and compared with similar records reported in the literature. The data appear to favor an interactionist view of lexical development which recognizes the contribution of particular syllabic forms to the acquisition of consonantal phonemes and the role these phonemes play in expanded syllabic form. The discussion argues for the primacy of CV as the dominant unit of production and identifies a number of constraints on syllabic forms and a set of conspiratorial rules which assure the production of these forms. Further, it is argued that certain strategies operating within the constraints to particular syllabic forms result in the ordered development of syllabic structures.  相似文献   
199.
This study investigates the influence of attention loading on the established intersensory effects of passive bodily rotation on choice reaction time (RT) to visual motion. Subjects sat at the center of rotation in an enclosed rotating chamber and observed an oscilloscope on which were, in the center, a tracking display and, 10° left of center, a RT line. Three tracking tasks and a no-tracking control condition were presented to all subjects in combination with the RT task, which occurred with and without concurrent cab rotations. Choice RT to. line motions was inhibited (p < .001) both when there was simultaneous vestibular stimulation and when there was a tracking task; response latencies lengthened progressively with increased similarity between the RT and tracking tasks. However, the attention conditions did not affect the intersensory effect; the significance of this for the nature of the sensory interaction is discussed.  相似文献   
200.
The effects of intertrial interval (ITI) and foreperiod duration on the acquisition of a conditioned emotional response were investigated using a four-trial conditioning procedure. The optimum ITI was found to be 60 s with a bidirectional gradient for conditioned suppression above and below 60 s. Conditioned supression was found to be directly related to foreperiod duration.  相似文献   
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