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911.
912.
Temporal control of behavior and the power law   总被引:9,自引:9,他引:0       下载免费PDF全文
The performance of rats and pigeons under fixed-interval schedules was studied in two experiments. The duration of postreinforcement pause was a declining proportion of fixed-interval duration. For pigeons this was true both when the duration of the reinforcer was fixed and when it was increased in direct proportion to increases in fixed-interval duration; the longer reinforcer durations did, however, lengthen the postreinforcement pause at higher schedule values. A quantitative analysis of data from Experiments 1 and 2 and from other studies showed that fractional exponent power functions described the relationship between postreinforcement pause and fixed-interval value; similar functions have previously been observed in studies of temporal differentiation. It was concluded that power functions reflect a direct causal, rather than artifactual, relationship between performance and the temporal requirements of reinforcement schedules.  相似文献   
913.
Three types of oculomotor programming disturbances are described in patients with the dementia syndrome. This report describes two of these abnormalities, poorly regulated gaze patterns and a programming type of gaze perseveration. All patients showed poorly regulated gaze patterns in contrast to the normal controls, whereas on the whole only the moderately affected patients showed the programming type of gaze perseveration. The third type of oculomotor programming disturbance is efferent perseveration of gaze (a hypokinetic, "staring" type of gaze pattern) and can be seen with severe dementia. The possible significance of these findings is discussed.  相似文献   
914.
This study tested the hypothesis that laterality and handedness researchers are more likely than other researchers to be left-handed. A questionnaire assessing hand preference was sent to authors of articles which either dealt with handedness (N = 50) or other aspects of laterality (N = 100) or did not concern laterality (N = 50). The proportion of left-handers was highest in the handedness group (12.9%) and lowest in the non-laterality group (5.0%), but this difference did not reach significance.  相似文献   
915.
Retention of a poison-based aversion after a 3-yr. period by 8 vervet monkeys (Cercopithecus aethiops) was found. The color of the visual cue appeared to effect the retention of the aversion.  相似文献   
916.
This investigation examined communication patterns between 16 randomly selected senior dental students and their child patients. Interactions were videotaped during a regular treatment appointment and analyzed according to four Practitioner Communication categories and four Child Cooperation categories. Communication categories included Directive Guidance Behavior, Permissive Behavior, Coercive Behavior, and Other Behavior. Child behavior categories included Cooperation, Resistance, Noncooperation, and Other. The probability that a given category of child's behavior would follow a given category of practitioner's behavior was calculated. Results indicated a .85 probability that Directive Guidance would be followed by Cooperation; a .67 probability that Permissiveness would lead to Noncooperation; and a .97 likelihood that Coerciveness would lead to either Noncooperation or Resistance. Practitioners' confidence was also considered; less confident operators account for 95% of the Coercive behaviors, 86% of Permissive behaviors and 87% of Uncooperative behaviors.  相似文献   
917.
Temporal imbalances between the successive stimulation of pairs of loci on each forearm altered judgments of the equality of the spatial extents between sets of loci. The spatial judgments became increasingly inaccurate as the temporal imbalance was increased, i.e., the Tau effect. Changes in stimulus intensity also influenced the dependency of spatial judgments on temporal factors. The data suggest that concomitant variations of spatial, temporal, and intensitive components of a vibrotactile stimulus "package" can produce systematic perceptual effects of potential significance in the design of vibrotactile sensory substitution systems.  相似文献   
918.
The central question at issue was the role of both infant and parent temperament in determining child adjustment at age 4. Within the conceptual framework of the New York Longitudinal Study (NYLS), both infant and parent temperament were assessed. Factor analyses yielded three comparable infant and parent temperament factors: Mood, Energy, and Consistency. Correlations with teacher ratings of child adjustment indicated the most significant relationship to be with the infant girls' Mood factor (comparable to the NYLS high-risk "difficult" infant factor). No infant factors were found to relate to boys' adjustment, while maternal Mood was significant across sexes. Indices of the temperamental similarity within families also revealed sex differences relative to adjustment, with similarity across all family members significantly related to adjustment for girls and boy-father dissimilarity significant for boys. Discussion centered around continuity-discontinuity issues relevant to sex differences.  相似文献   
919.
This experiment examined the role of cognitive flexibility-rigidity in memory. On the basis of several personality tests, subjects were classified as flexible, intermediate, or rigid, using a postexperimental blocking procedure. All subjects were given a perceptual grouping task, which masks the meaningful structure of the material. Subjects have the option of discovering the more meaningful structure consisting of word pairs, or alternatively, processing less meaningful chunks of letters. Results were that flexible subjects recalled substantially more items than intermediate and rigid subjects, in that order. In addition, subjects given different (varied) groupings of the letter chunks recalled substantially more than subjects given repeated presentations of the same grouping structure. Transfer tests indicated that subjects acquired different coding strategies under varied and constant input. Repetitious input led subjects to adopt inefficient strategies in processing the material to be remembered, whereas varied input led subjects to adopt efficient encoding strategies.  相似文献   
920.
A series of studies investigating the psychometric and conceptual properties of the Survey of Ethical Attitudes (SEA), a paper-and-pencil measure of moral reasoning, is reported. The results of these studies indicate that the scale is clearly susceptible to the influence of response dissimulation in the form of both role-playing and impression management, and is also confounded with sources of stylistic variance in the form of social desirability. Previous proposals concerning the relationships among moral development, moral reasoning, and personality structure are reviewed in light of these findings, and an alternative conceptualization of the measure in terms of political and social attitudes is offered.  相似文献   
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