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71.
Summary Four experiments were conducted to examine processes in identification and selective adaptation of hues in color perception that exactly parallel processes in identification and adaptation of auditory detectors that provide information for phonemic perception. The first experiment demonstrated an effect of adaptation on identification of blue and green when a hue category center was used as the adaptor; this experiment also assessed recovery from adaptation. Adaptation to one hue was found to shift identification to favor the alternative hue, implicating a single detector underlying hue categorization. The second experiment demonstrated similar effects of adaptation between green and yellow. The third experiment compared the magnitudes of shift following adaptation with a category center, a near-boundary hue, and variously graded adaptation series. Adaptation was found to be related to the category representativeness of the adaptor(s). Results of the third experiment also provided support for the view that adaptation, rather than response bias, is responsible for shifts in the position of identification functions following extended stimulus exposure. The fourth experiment explored the neural loci of adaptation by an interocular transfer test. Hue adaptation was found to occur at both central and peripheral loci. In the four main experiments, reaction times to identify hues in unadapted and adapted states were also analyzed and compared. Subsidiary experiments assessed the effects of stimulus luminance on the magnitude of adaptation. General principles of categorical perception and its underlying bases, including the sweep, magnitude, and symmetry of adaptation, are discussed. The principal findings of these studies provide new data on hue perception which strikingly parallel findings in speech perception.  相似文献   
72.
Do alcoholic Korsakoff's syndrome patients acquire affective reactions?   总被引:1,自引:0,他引:1  
In this study we report two experiments that investigate the acquisition of affective reactions. In Experiment 1, unfamiliar melodies were played to Korsakoff's syndrome patients and alcoholic and nonalcoholic control subjects who were matched with them according to age and education. Following a retention interval of 5 min, subjects received a preference test on old and new melodies. Korsakoff's syndrome patients showed the same increase in preference for old melodies as a consequence of prior exposures as control subjects did, but their recognition of melodies was significantly impaired in comparison with controls. In Experiment 2, the same subjects saw photographs of two men. Fictional biographical information depicted one as a "good guy" and the other as a "bad guy." After a retention interval of approximately 20 days, Korsakoffs recalled virtually none of the biographical information; however, 78% preferred the good guy, and impression ratings were less favorable for the bad guy. Korsakoff patients developed preferences and impressions even though they did not have voluntary access to the information on which the preferences were based. However, their impression ratings were less extreme than those of controls. The pattern of results of the two studies is discussed in terms of Johnson's (1983) MEM model of memory.  相似文献   
73.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
74.
Sleep laboratory studies of patients complaining of insomnia have demonstrated discrepancies between subjective reports and electroencephalograph (EEG)-recorded measures. In our research studies on sleeping aids, 60% of the self-described poor sleepers who reported usual sleep latencies of at least 45 min did not meet the laboratory qualification criterion of a 30-min or longer sleep latency. To learn to predict who would qualify for our studies, we compared 30 laboratory-qualified poor sleepers (QPS) with 30 laboratory-disqualified poor sleepers (DPSs) on subjective report, mood, and all-night sleep laboratory variables. QPSs had significantly lower sleep efficiency and total sleep time in the laboratory, but these differences were due to the longer sleep latencies (50.7 +/- 27.8 min vs. 15.2 +/- 6.1 min) of the QPS group. QPSs and DPSs differed significantly in their morning estimates of their laboratory sleep latencies; as a group, QPSs gave an accurate estimate (51.6 +/- 27.8 min), but DPSs were significantly more likely to exaggerate their sleep latencies. Although we did not identify ways of predicting which poor sleepers would show sleep-onset insomnia in the sleep laboratory, we did find that, in this young, healthy population, there are poor sleepers who give an accurate report of a rather severe sleep-onset insomnia.  相似文献   
75.
A modification in scoring the ABC Scale   总被引:1,自引:0,他引:1  
The scoring procedures for the Articulation of the Body-Concept (ABC) Scale to use with three-, four- and five-year-old children were modified to determine their degree of field-dependence-independence. A total of 300 children, who obtained a score of one or better on the ABC Scale, were administered the Preschool Embedded Figures Test (PEFT) and the ABC Scale. The ABC Scale was scored using its scoring procedures and the scoring procedures for the Goodenough-Harris Drawing Test (GHDT). Scores on the PEFT, ABC Scale and GHDT were correlated with each other. Correlations among all cognitive measures ranged from .88 to .99, which were high and statistically significant (p < .0001). Therefore, the scoring procedures for the GHDT can be substituted in scoring the ABC Scale in assessing young children's field-dependence-independence.  相似文献   
76.
The major purpose of this study was to investigate aphasic patients' STM for visual stimuli which are difficult to encode. The effect of a varied information rate and information load per item was tested, and so was the relation between primacy and recency scores. The investigation included memory both for content and for position. Each item group in the tests consisted of a time sequence of squares with internal grid lines and a dot in one of the cells. The location of the dot had to be remembered. Both the aphasic group and the control group included 24 persons matched for age. The aphasic group showed a somewhat lower overall score than the normal group. Apart from the interaction between groups and information load, no signifcant interactions were observed. However, there was a systematic tendency over tests towards a relatively lower recency score in the aphasic group.  相似文献   
77.
78.
Microcomputer-assisted relaxation   总被引:1,自引:0,他引:1  
The present pilot study was designed to test the effectiveness of a microcomputer program developed by the authors to induce relaxation and focused attention, which are common to most clinical stress-reduction and hypnotic procedures. A nonclinical sample of 20 adults used the program on an APPLE IIc computer in two 30-min. sessions in a within-subjects design. Repeated measures analyses of variance showed significant decreases in the Spielberger State Anxiety Scale and on a visual analog anxiety scale. Limitations and implications of the study are discussed.  相似文献   
79.
This project studied the effects of weather variables and size of the population on minor and major violence rates within six prisons in the Kingston, Ontario, Canada area from January, 1980 through December, 1983. While weather variables have been studied in relation to mood changes within the general population, this study was the first to analyze the impact of weather variables on rates of violence within the prison setting using forward inclusion multiple regression. Analysis showed that population size consistently appeared positively correlated with assaults on other inmates among the male medium-security prisoners during the summer months. In the summer months, temperature tended to be positively related to some minor kinds of offenses, but in the winter months the relationship was negative. Humidity, rain, sunshine hours, snow, and snow on the ground were not consistently related to incidences of minor and major violence. Indices of geomagnetic disturbances had statistically significant inverse relationships with attempted suicide/self-inflicted injury rates among the male prisoners during the summer months. Over 12 months, wind was generally negatively correlated with incidences of major and minor violence among the male inmates. For 6-mo. periods, wind was generally positively correlated with violence rates during the winter months and negatively correlated during the summer months among the male inmates. The findings relating weather variables to violence rates in the women's prison were consistently in opposition to those found for male prisoners during the 4-yr. period.  相似文献   
80.
For four of six autistic children who underwent intensive behavioral treatment, the nature of their self-stimulatory behavior changed from initial lowlevel motor behaviors (such as rocking, spinning, twirling) to differing kinds of higher-level behaviors (such as lining of objects, echolalic speech, and preoccupation with spelling and numerical values). The children who changed to the highest levels of self-stimulatory behavior also showed the largest gains in treatment (as determined by IQ scores, school placement, etc.). The changes in self-stimulatory behaviors were attributed to the intense teaching of appropriate social behaviors and the explicit therapeutic suppression of low-level, self-stimulatory behaviors. The long-term therapeutic effects of changing from lower-to higher-level forms of self-stimulatory behavior were discussed.This study was supported by a grant from the National Institute of Mental Health (grant MH 11440). We want to express our thanks to the parents who allowed us to study their children. We gratefully acknowledge the assistance of Maria Audero with the design of the weighted measure, and Tracee Parker with the collection of the data.  相似文献   
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