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921.
Symmetry and transitivity of conditional relations in monkeys (Cebus apella) and pigeons (Columba livia) 总被引:10,自引:10,他引:0 下载免费PDF全文
D'Amato MR Salmon DP Loukas E Tomie A 《Journal of the experimental analysis of behavior》1985,44(1):35-47
In Experiment 1 six monkeys were tested with discriminative relations that were backward relative to their training in a 0-second conditional (“symbolic”) matching procedure. Although there was some indication of backward associations, the evidence was generally weak, and statistical evaluations did not reach conventional significance levels. Unlike children, who show backward associations to the point of symmetry, monkeys and pigeons display at best only weak and transient backward associations. In Experiment 2 associative transitivity was assessed across two sets of conditional matching tasks. All four monkeys tested demonstrated strong transitivity. In contrast, in Experiment 3 there was no evidence of transitivity in three pigeons tested under conditions closely comparable to those of Experiment 2. These results may identify some key features of interspecies differences and contribute to analyses of serial learning in animals. 相似文献
922.
24 women over 60 yr. and 24 younger women rated the severity of life stress events drawn from a pool of events occurring to elderly people. There were no over-all age differences, but rather strong agreement on which events were most threatening. There was some evidence, however, that the old rated 'severe' death events as less threatening than younger women. 相似文献
923.
Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed. 相似文献
924.
Correlations (r = 0.50) were found between the numbers of different psi (paranormal) experiences and the numbers of temporal lobe signs within a population of university students (n = 99). The strongest correlation of 0.60 occurred with a cluster of signs that are similar to symptoms reported by patients who show chronic foci in the mesiobasal temporal lobe. However, there were no significant correlations between numbers of different psi experiences and clusters of control items or a lie scale. Specific analyses of the 140 items of the inventory indicated only 23 reached statistical criterion (p less than .001). Of these 17 were direct temporal lobe signs that implied deepened affect, auditory-vestibular experiences (vibrations, hearing one's name called), olfactory auras, perseveration ("forced" thinking), depersonalization, and sense of the personal. Five items involved beliefs about exotic phenomena or philosophical ideas. Only one item was from a control cluster. These results support the hypothesis that mystical or paranormal experiences are associated with transient electrical foci within the temporal lobe of the human brain. The repeated occurrence of these experiences within normal individuals may be embedded within a more complex symptomatology of temporal lobe signs. 相似文献
925.
E R Delay 《Perceptual and motor skills》1985,60(2):479-483
Locomotor activity of male, albino rats (25, 90, and 200 days old at the start of the experiment) was measured in conditions of light and dark. Continuous and pulsed noises of 50, 60, 70, 80 and 90 dB were presented under each illumination condition. While noise intensity altered activity of all age groups, it interacted with illumination and age, resulting in different sensory-dependent patterns of activity in each age group. The results are interpreted in terms of arousal theory and potential functional development of CNS structures regulating the effects of ambient sensory input on behavior. 相似文献
926.
R M Olig R D Staton W W Beatty H Wilson R I Biberdorf S G Hoag R A Brumback 《Perceptual and motor skills》1985,60(3):879-889
Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed. 相似文献
927.
Tympanic thermometers were used to measure fluctuations in the temperature of the left and right hemispheres of 22 normal high school students while performing verbal and nonverbal visual discrimination tasks. The nonverbal task involving face recognition demonstrated the predicted effect of hemispheric bias on performance: The subjects performed better when they showed a relative rise in right-hemisphere temperature. No significant relationship between hemispheric temperature and level of performance was observed during the verbal task, perhaps owing to the opportunity to treat effectively the nonwords as either linguistic strings or visual patterns. It is concluded that tympanic temperature effectively measures hemispheric activity during cognitive processing. 相似文献
928.
A Montare 《Perceptual and motor skills》1985,60(3):871-877
College students of both sexes served as their own controls to test three hypotheses in each of two separate experiments designed to assess the learning effects of knowledge of results upon time estimation. The results indicated that (1) knowledge of results in the form of feedback to the nearest hundredth of a second significantly increased the mean accuracy of time estimations obtained by the method of production, (2) that knowledge of results significantly decreased the variance of the time estimations, and (3) that sex difference as a main effect was not significant in either experiment. A major conclusion of the present study was that variance represents an authentic and independent measure of learning. 相似文献
929.
R E Koslow 《Perceptual and motor skills》1985,60(2):351-354
The subjects were 16 college students assessed as having normal, uncorrected visual abilities. Each subject responded to the appearance of each of five variously colored ball sections as they were introduced into the subjects' visual field. Analysis indicated that colors with luminance values greater than 70 CD/M2 (black, blue, green) were detected further in the horizontal peripheral plane than were colors possessing values less than 36 CD/M2 (red, purple). 相似文献
930.
Subjects in a prior study of complex learning often experienced difficulty in mastering the task because of an apparent reluctance to release one perceptual field and reconstrue the task on a higher cognitive level. It was hypothesized that were this the correct explanation, the faster learners would be more field independent on a measure of field dependence, since independence has been defined in terms of ease in releasing one's attention from the immediate perceptual field. This hypothesis was tested with 22 undergraduate subjects for whom Group Embedded Figures Test scores were correlated with the number of trials to completion on the complex learning task. A moderate but significant correlation supported the hypothesis. 相似文献