全文获取类型
收费全文 | 52722篇 |
免费 | 2181篇 |
国内免费 | 36篇 |
出版年
2020年 | 632篇 |
2019年 | 734篇 |
2018年 | 1049篇 |
2017年 | 1071篇 |
2016年 | 1100篇 |
2015年 | 808篇 |
2014年 | 939篇 |
2013年 | 4215篇 |
2012年 | 1674篇 |
2011年 | 1845篇 |
2010年 | 1173篇 |
2009年 | 1119篇 |
2008年 | 1553篇 |
2007年 | 1489篇 |
2006年 | 1337篇 |
2005年 | 1193篇 |
2004年 | 1118篇 |
2003年 | 1132篇 |
2002年 | 1096篇 |
2001年 | 1851篇 |
2000年 | 1775篇 |
1999年 | 1305篇 |
1998年 | 615篇 |
1997年 | 548篇 |
1996年 | 497篇 |
1995年 | 482篇 |
1993年 | 476篇 |
1992年 | 1083篇 |
1991年 | 1034篇 |
1990年 | 1004篇 |
1989年 | 938篇 |
1988年 | 881篇 |
1987年 | 860篇 |
1986年 | 851篇 |
1985年 | 918篇 |
1984年 | 730篇 |
1983年 | 610篇 |
1981年 | 476篇 |
1979年 | 683篇 |
1978年 | 544篇 |
1977年 | 505篇 |
1975年 | 623篇 |
1974年 | 686篇 |
1973年 | 681篇 |
1972年 | 585篇 |
1971年 | 497篇 |
1969年 | 529篇 |
1968年 | 601篇 |
1967年 | 503篇 |
1966年 | 588篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
Michael S. Patton 《Journal of religion and health》1986,25(4):291-302
This article demonstrates the progress that medicine, psychiatry, religion, and anthropology have made toward a variant perspective, of masturbation. Researchers documented the suffering and damage caused by classically ingrained religious and medical distortions.The secret sin of Judeo-Christianity and the social disease of nineteenth-century medicine has paradoxially become the therapy for various forms of psychosexual dysfunction. Catholic, Protestant, and Jewish denominations polarize opinions from rigorous orthodoxy to unconditional acceptance of this psychosexual behavior as a source of emotional homeostasis.Michael S. Patton, Ph.D., is an anthropologist concerned with sex research in society, history, and religion. He lives in Mansfield, OH 44903. 相似文献
912.
Drug-behavior interaction history: modification of the effects of morphine on punished behavior. 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Journal of the experimental analysis of behavior》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Squirrel monkeys were trained to respond under a multiple fixed-interval, fixed-interval schedule in which the first response after 5 min terminated a visual stimulus in the presence of which electric shocks could occur. During one component of the schedule, correlated with one color of stimulus lights, every 30th response also produced electric shock; responding was suppressed during this component to approximately 10 to 12% of that occurring in the alternate component in which responding was not punished. In contrast to previous research, morphine (0.03 to 1.0 mg/kg) increased punished responding. Unpunished responding, however, was either not affected or decreased at doses of morphine that increased punished responding. Increases in rate of punished responding also occurred when the single-schedule punishment condition was studied alone in these animals. Subsequent experimentation, which systematically analyzed the development of the rate-enhancing effects of morphine on punished responding, involved the study of drug effects in additional monkeys trained initially under a single-schedule punishment condition. The effects of morphine on punished responding were studied before, after, and then during exposure to the multiple schedule that included a component in which responding was not punished. Increases in response rate with morphine did not occur until it was administered during exposure to the multiple schedule that included a component in which responding was not punished. As with the other monkeys, once the rate increases in punished responding occurred under the multiple schedule, these effects of morphine persisted, even when the multiple schedule was removed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
913.
Theories of observing differ in predicting whether or not a signal for absence of reinforcement (S−) is capable of reinforcing observing responses. Experiments in which S− was first removed from and then restored to the procedure have yielded mixed results. The present experiments suggest that failure to control for the direct effect of presenting S− may have been responsible. Pigeons and operant procedures were used. Experiment 1 showed that presentations of S−, even when not contingent on observing, can raise the rate of an observing response that was reinforced only by presentations of a signal (S+) that accompanied a schedule of food delivery. Experiment 2 showed that this effect resulted from bursts of responding that followed offsets of S−. Experiment 3 showed that, when the presence of S− was held constant, lower rates occurred when S− was dependent on, rather than independent of, observing. These results support theories that characterize S− as incapable of reinforcing observing responses. 相似文献
914.
Preference for less segmented fixed-time components in concurrent-chain schedules of reinforcement 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Journal of the experimental analysis of behavior》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A concurrent-chain procedure was used to examine choice between segmented and less segmented response-independent schedules of reinforcement. A pair of independent, concurrent variable-interval 60-s schedules were presented in the initial link, along with a 1.5-s changeover delay. A chained fixed-interval fixed-time and its corresponding tandem schedule constituted the terminal links. The length of the fixed-interval schedule in the terminal link was varied between 5 s and 30 s while that of the fixed-time schedule was kept at 5 s over conditions. The first components of both terminal-link schedules were accompanied by the same stimulus. Except in the baseline condition, the onset of the second component of the terminal-link chained schedule was accompanied by either a localized (key color) or a nonlocalized (dark houselight) stimulus change. Stimulus conditions were constant during the terminal-link tandem schedule. With three exceptions, pigeons demonstrated a slight preference for the tandem over the chained schedule in the terminal link. Furthermore, this preference varied inversely with the length of the first component. In general, these results are consistent with previous studies that reported an adverse effect on choice by segmenting an interval schedule into two or more components, but they are inconsistent with studies that reported preference for signaled over unsignaled delay of reinforcement. 相似文献
915.
Relationship between Knapp's metaphor scale of attitudes toward time and subjective estimation of fixed time intervals, measured by a modification of Lovett Doust's method, was described. Results were discussed within the framework of studies relating the measurements of cognitive styles and altered consciousness states to the dilated or accelerated perceptions of time. 相似文献
916.
Syntactic decoding reaction times of 20 learning disabled children comprising two groups of subjects (mean age of 8 and 13 yr., respectively) were compared to the responses of normal controls matched for age and sex. An analysis of variance procedure showed that the learning disabled children and their normal peers did not differ significantly in responses to the experimental stimuli. This held true regardless of linguistic complexity, suggesting that delays in processing elementary syntactic constructions are not a concomitant of learning disabilities. 相似文献
917.
The purpose of this study was to examine the influence of age, sex, etiology, and degree of hearing loss on the static and dynamic balance performance of hearing impaired children and youth (N = 132), ages 3 to 14 yr. The subjects were individually assessed on Items 2 and 7 of Subtest 2 of the Short Form of the Bruininks-Oseretsky Test of Motor Proficiency. As expected, performance on both tasks improved with chronological age. In comparing the performance of subjects by etiology, only one significant difference emerged; those with genetic deafness were superior on static balance to those whose deafness was idiopathic. However, the mean scores for the genetic group were superior for both balance tasks. The sex of the child as well as extent of hearing loss did not affect performance in either task. 相似文献
918.
The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated. 相似文献
919.
S Taylor 《Perceptual and motor skills》1986,63(3):1300-1302
The texton theory of preattentive texture perception was recently adopted over a prior model based on the global computation of dipole statistics. It is shown here that the dipole model remains a necessary adjunct unless the texton theory is modified to distinguish real from virtual features of texture perception. 相似文献
920.
K Leonhard 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(12):703-709
Many years ago the author, jointly with a psychologist, described a patient who, in spite of her alleged idiocy, showed an exceptional musical capacity. However, in the meantime the author has recognized and described early childhood catatonics and, as a consequence of this new knowledge, he has to admit an error. Even according to our then findings it would have been identifiable that, as has been confirmed now by follow-up, the patient is suffering from catatonia, starting in infancy. The high musical performance, then arousing our greatest astonishment, is now explicable, for childhood schizophrenics do not develop general mental deficiency but only specific circumscribed deficits. 相似文献