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961.
Perceptual masking was studied under binocular and dichoptic conditions in order to separate peripheral and central interference effects. Under binocular conditions, when the test flash (TF) and the blanking flash (BF) fell on both retinas, both retroactive and proactive masking were demonstrated. Under dichoptic conditions, when the TF fell on one eye and the BF on the other eye, thus eliminating opportunity for intraretinal interference, there was partial retroactive perceptual masking and no proactive masking. These results suggest that binocular proactive masking is due to peripheral light adaptation, that binocular retroactive masking is due to both peripheral and central effects, and that dichoptic masking is due solely to central retrochiasmal interference. It is proposed that dichoptic retroactive perceptual masking affords a method of investigating central perception time, i.e., the time to consolidate a perceptual experience.  相似文献   
962.
Luminance thresholds for downward moving contours were measured under several conditions of adaptation. Included was one condition which desensitized visual mechanisms responsive to downward motion. Another condition exerted equal effects on both up- and down-sensitive mechanisms. Thresholds for moving contours were unaffected by exposure to contours which moved in the opposite direction. This indicates that the perception of motion does not depend upon the relative activity in oppositely tuned, directionally selective visual mechanisms.  相似文献   
963.
Rhesus monkeys were trained to make auditory frequency, intensity, and duration discriminations. Initial training was carried out with a procedure which allowed the utilization of either relational cues or absolute cues. Later tests with similar auditory parameters allowed only the utilization of relational cues. Performance on these latter tests indicated that relational rather than absolute cues had been utilized when both types were available on the frequency and intensity discrimination tasks. However, absolute rather than relational cues were apparently utilized in making duration discriminations.  相似文献   
964.
Taste profiles were obtained for 26 compounds after adaptation to distilled water and also for water after adaptation to each of the 26 compounds. Each of the four “basic tastes” was induced in water by adaptation to certain of the compounds. Compounds having similar tastes did not necessarily have similar water tastes. The results imply a peripheral locus of the water taste mechanism(s).  相似文献   
965.
Patterns were computer-generated about two prototypes to form schematic clusters of three diameters about the cluster centroids. In a schematic concept-formation task, recovery of a priori schematic class membership by Os varied inversely as physical cluster diameter, with concept acquisition across trials evidenced in only the low-cluster-diameter condition. For each 0 who failed to classify according to the schema rule, linear discriminant function analysis was applied to his classes. In all cases, O-generated classes were successfully recovered by the physical pattern features used as predictors, the mapping of these classes by the LDF exceeding that by the schema rule in accuracy at all cluster-diameter levels.  相似文献   
966.
Users of interobserver agreement statistics have heretofore ignored the problem of autocorrelation in behavior sequences when testing the statistical significance of agreement measures. Due to autocorrelation traditional reliability tests based on the 2 × 2 contingency-table model (e.g., kappa, phi) are incorrect. Correct tests can be developed by using the bivariate time series as a statistical model. Seen from this perspective, testing the significance of interobserver agreement becomes formally equivalent to testing the significance of the lag-zero cross-correlation between two time series. The robust procedure known as the jackknife is suggested for this purpose.  相似文献   
967.
968.
The moments of a nonnegative bounded waveform (e.g., bounded probability density functions or responses that can be expressed as bounded probability density functions) provide the basis for characterizing the waveform. Traditionally, only the lower-order moments (k ≤ 4) have been utilized in deriving topographical indices of these waveforms. Recent advances in waveform moment analysis, however, have made it possible to derive comprehensive and interpretable indices of complex nonnegative bounded waveforms by utilizing both lower-order and higher-order moments. Waveform moment analysis is reviewed briefly, and a flexible and efficient computer program is presented for conducting waveform moment analyses.  相似文献   
969.
“Same” and “different” responses to stimuli that result in strong and weak single phenomenal wholes were investigated. Present and also previous results indicate that strong phenomenal wholes tend to be associated with a fast “same” and slow “different” response pattern. This result suggests that the parts of strong phenomenal wholes are perceived as more similar (e.g., because it should be easier to respond “same” to more similar stimuli). This suggestion is consistent with results based on other measures of perceived similarity. Present and also previous results additionally indicate that strong phenomenal wholes are frequently associated with superior overall (“same” plus “different”) performance. This result is consistent with evidence that the identification of simultaneously occurring multiple targets improves when they belong to the same phenomenal whole. The present results also hint that attention can affect whether two or three objects form the effective (functional) whole and support the assimilation explanation of the Müller Lyer illusion.  相似文献   
970.
A survey on attitudes toward nuclear war and disarmament is used to test two hypotheses: (1) the fundamentally different world orientations of males and females will be reflected in different factor structures for attitudes toward nuclear war and disarmament, and (2) males are more pro-force than females. A confirmatory factor analysis was used to test the first hypothesis. In addition, components of the separate factor structures for males and females were compared. Differences between the means for males and females on three factors extracted from the entire sample were used to test the second hypothesis. Both hypotheses were found to hold for the present sample. Interpretation of the differing factor structures for males and females is presented as well as implications for the more pro-force emphasis of males.  相似文献   
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