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991.
The projective test literature on aging is reviewed. It was concluded that, while much critical research remains to be done and many of the studies are flawed, projective testing has contributed a great deal to the understanding of the aging process and has yielded a core of consistent findings. Suggestions for future research which would help resolve some current ambiguities were made.  相似文献   
992.
The SOMPA is examined in terms of the multicultural model and Mercer's justification for multiple normal distributions within that model. The philosophical basis of the approach and the environments in which any assessment strategy must function are also examined. It is concluded that multiple normal distributions are not justified based on the variance accounted for in WISC-R scores by the Sociocultural Scales of the SOMPA. The pholosophical basis of the SOMPA, the sociology of knowledge, is not considered helpful or useful in the assessment process because of internal logic problems associated with the paradigm and because it creates an artificial separation of populations. Some of the components which influence education are examined in an effort to place the SOMPA in a realistic operational environment and to contrast the complexity of that environment with the oversimplified view offered by the SOMPA.  相似文献   
993.
Based on an attribution theory analysis, it was predicted that normal individuals (people who do not evidence a particular target problem) would be least motivated to seek help for a psychological problem when they believe that the problem is actuarially common (i.e., high consensus). Based on an analysis of how target problem people evaluate their psychological problem, however, it was predicted that such individuals (unlike normal individuals) should be maximally motivated to seek help when they believe that the problem is common. To test these predictions, target problem and normal individuals (high vs. average test anxious females) were given feedback that they possessed a problem (test anxiety). Individuals were then told that their problem was either common, uncommon, or given no consensus information. As predicted, the higher consensus information led to the least help-seeking behavior for the normal individuals and to the most help-seeking behavior for the target problem individuals.  相似文献   
994.
Hill-climbing by pigeons   总被引:12,自引:12,他引:0       下载免费PDF全文
Pigeons were exposed to two types of concurrent operant-reinforcement schedules in order to determine what choice rules determine behavior on these schedules. In the first set of experiments, concurrent variable-interval, variable-interval schedules, key-peck responses to either of two alternative schedules produced food reinforcement after a random time interval. The frequency of food-reinforcement availability for the two schedules was varied over different ranges for different birds. In the second series of experiments, concurrent variable-ratio, variable-interval schedules, key-peck responses to one schedule produced food reinforcement after a random time interval, whereas food reinforcement occurred for an alternative schedule only after a random number of responses. Results from both experiments showed that pigeons consistently follow a behavioral strategy in which the alternative schedule chosen at any time is the one which offers the highest momentary reinforcement probability (momentary maximizing). The quality of momentary maximizing was somewhat higher and more consistent when both alternative reinforcement schedules were time-based than when one schedule was time-based and the alternative response-count based. Previous attempts to provide evidence for the existence of momentary maximizing were shown to be based upon faulty assumptions about the behavior implied by momentary maximizing and resultant inappropriate measures of behavior.  相似文献   
995.
996.
997.
The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.  相似文献   
998.
999.
If spatial memory tasks are considered as foraging problems, it can be predicted that rats' difficulty in learning a win-stay task—revisiting part of a maze where food has recently been found—should be partly overcome if the food is not fully consumed at the first visit (nondepleted reward) rather than being all eaten (depleted reward). Three experiments confirmed and further analysed this result. Experiments 1 and 2 showed that it does not depend on the amount of food initially found; nor is win-stay performance affected by the amount of food actually eaten. Experiment 3 suggested that the effects of nondepleted reward are mainly due to the animals' being interrupted while eating, and very little to the fact that uneaten food is left behind. The results are discussed with regard to their implications for learning theory, and for the application of foraging theory to learning and memory experiments.  相似文献   
1000.
Seven contingency theories of classical and instrumental conditioning were defined in relation to the contingency matrix and to six separate probabilities which can be derived from this matrix. These theories were compared on the basis of formal similarities and differences, and were judged against three separate empirical variables which have been discussed in the contingency literature: the duration of the intertrial interval, partial reinforcement, and negative contingencies between the two events of conditioning. All previous theories had some difficulty predicting the effects of one or more of these variables upon animal conditioning. Also, some formulas make the unusual prediction that there will be less conditioning when there is more than one conditioning trial. The paper concluded with an extensive discussion of the problems that are created by conditioning events with temporal extension; events which are then categorized by a contingency matrix which has no temporal character. Some possible solutions to the problems were discussed.  相似文献   
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