首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   7795篇
  免费   1141篇
  国内免费   923篇
  2024年   23篇
  2023年   163篇
  2022年   168篇
  2021年   259篇
  2020年   435篇
  2019年   445篇
  2018年   395篇
  2017年   470篇
  2016年   476篇
  2015年   307篇
  2014年   392篇
  2013年   1180篇
  2012年   270篇
  2011年   335篇
  2010年   249篇
  2009年   352篇
  2008年   386篇
  2007年   359篇
  2006年   332篇
  2005年   320篇
  2004年   309篇
  2003年   260篇
  2002年   225篇
  2001年   183篇
  2000年   171篇
  1999年   142篇
  1998年   118篇
  1997年   95篇
  1996年   94篇
  1995年   103篇
  1994年   88篇
  1993年   69篇
  1992年   49篇
  1991年   65篇
  1990年   39篇
  1989年   48篇
  1988年   40篇
  1987年   40篇
  1986年   26篇
  1985年   38篇
  1984年   44篇
  1983年   29篇
  1982年   40篇
  1981年   30篇
  1980年   37篇
  1979年   39篇
  1978年   32篇
  1977年   36篇
  1976年   34篇
  1975年   15篇
排序方式: 共有9859条查询结果,搜索用时 15 毫秒
221.
The goal of this review is to compare two divergent lines of research on signal-centered behavior: the orienting reflex (OR) and autoshaping. A review of conditioning experiments in animals and humans suggests that the novelty hypothesis of the OR is no longer tenable. Only stimuli that represent biological “relevance” elicit ORs. A stimulus may be relevant a priori (i.e., unconditioned) or as a result of conditioning. Exposure to a conditioned stimulus (CS) that predicts a positive reinforcer causes the animal to orient to it throughout conditioning. Within the CS-US interval, the initial CS-directed orienting response is followed by US-directed tendencies. Experimental evidence is shown that the development and maintenance of the conditioned OR occur in a similar fashion both in response-independent (classical) and response-dependent (instrumental) paradigms. It is proposed that the conditioned OR and the signal-directed autoshaped response are identical. Signals predicting aversive events repel the subject from the source of the CS. It is suggested that the function of the CS is not only to signal the probability of US occurrence, but also to serve as a spatial cue to guide the animal in the environment.  相似文献   
222.
Wasserman suggested in a recent book review that the study of intervening cognitive processes represents a current focus of interest in animal learning and that this has led to a revitalization of comparative psychology. An examination of the volume reviewed suggests that he may have overstated the case. Most of the authors to whom he refers expressed dissatisfaction with traditional stimulus-response associationism but few argued for the extreme (information processing) sort of cognitive approach described by Wasserman.  相似文献   
223.
The acquisition of observing.   总被引:6,自引:6,他引:0       下载免费PDF全文
Pigeons were exposed to stimuli correlated with the presence or absence of a variable-interval 60-second schedule of reinforcement only while they depressed a crossbar or "perch." In the first experiment, the stimuli were different tilts of a line displayed on the key. When the difference in brightness between the line and the background (salience) was maximal, seven of eight birds acquired the discrimination, but when the difference was reduced by 50%, only one succeeded. In the second experiment, wavelength of chamber illumination served as the relevant dimension. Neither experiment showed a large effect attributable to the magnitude of the difference (disparity) between the positive and the negative stimulus. Individual differences in time spent observing were positively correlated with level of discrimination in the presence of the stimuli. All birds produced the positive stimulus for a greater proportion of the available time than they did the negative stimulus. This may be the mechanism that provides selective reinforcement of observing. Finally, the formation of a discrimination was analyzed in terms of changes in the proportion of time spent in contact with the discriminative stimuli.  相似文献   
224.
Restricted multidimensional scaling models for asymmetric proximities   总被引:1,自引:0,他引:1  
Restricted multidimensional scaling models [Bentler & Weeks, 1978] allowing constraints on parameters, are extended to the case of asymmetric data. Separate functions are used to model the symmetric and antisymmetric parts of the data. The approach is also extended to the case in which data are presumed to be linearly related to squared distances. Examples of several models are provided, using journal citation data. Possible extensions of the models are considered. This research was supported in part by USPHS Grant 0A01070, P. M. Bentler, principal investigator, and NIMH Grant MH-24819, E. J. Anthony and J. Worland, principal investigators. The authors wish to thank E. W. Holman and several anonymous reviewers for their valuable suggestions concerning this research.  相似文献   
225.
This investigation examined the use of six explicitly defined verbal self-correction behaviors by fluent and nonfluent aphasic subjects of high and low verbal ability, and by subjects further classified into six groups according to type of aphasia (Broca's, Anomic, Wernicke's etc.). Aphasic groups, on the average, generated some type of verbal self-correction effort on more than half of their initially erroneous responses, and the proportions of these efforts did not differ between aphasic patient groups. Significant differences in self-correction success were found, however, between groups classified according to fluency and severity, as well as among the six groups based on type of aphasia. In the former case, distinctions in self-correction skill favored high-verbal-ability groups regardless of fluency classification. In the latter instance, the subgroups typically formed by less severely impaired patients (Anomic and Broca's) had significantly higher proportions of successful self-correction behaviors than those comprised of individuals with more severe involvement (Wernicke's and Broca's plus severely limiting apraxia of speech). Between-group differences for specific types of self-correction behaviors occurred rarely, but those which were found could be related to characteristics of the particular aphasic groups under consideration. Verbal self-correction behavior is discussed as a behavioral reaction to an erroneous response or dissatisfaction with the quality of an intended response. These behaviors are viewed as indicators of the intactness of an aphasic individual's self-monitoring system, and of his tolerance for responses that are qualitatively limited by his verbal deficits.  相似文献   
226.
227.
There have been comparatively few attempts on either the conceptual or empirical level to integrate values, preferences, needs, work ethics, and orientations to work. A rationale outlining the way these concepts can be related to each other, is presented. It is maintained that these concepts are categories of relations between humans and work. These categories are qualitatively similar and differ principally in the level of generality of the characteristics of work considered. Complete-link cluster analysis is suggested as a method of analysis compatible with the proffered rationale. Two studies are presented with data gathered during the development of two versions of Work Aspect Preference Scale (WAPS). The samples for the two studies both comprised senior high school students, controlled for sex and age, who were administered the WAPS. Study 1 had a sample of 532 while Study 2 had a sample size of 482. Both sets of data were cluster analyzed. Results indicated a very substantial amount of agreement between the two samples, particularly at the more general levels of clustering. The bipartite and tripartite groupings of vocational needs suggested by L. H. Lofquist and R. V. Dawis (Journal of Vocational Behavior, 1978, 12, 12–19) were confirmed as were the findings of J. Mortimer (Sociology of Work and Occupations, 1975, 2, 29–53). Other clusters were also identified with findings from previous research. It is concluded that the investigation of preferences at different levels of generality and the interrelation between these levels shows great promise for both the researcher and the counselor and therefore merits more research effort.  相似文献   
228.
This study examined the interaction between preferred modes of information processing (visual and verbal) and two cognitively-based anxiety-reduction techniques. One technique was based on the use of images as a coping strategy while the other employed a self-instructional approach. Thirty-six subjects reporting high levels of dental fear were assigned to one of three groups (two types of treatment and a no-treatment control). One-half of the subjects in each group had been identified as preferring the visual mode of information processing while for the other half the verbal mode was preferred. After treatment, subjects viewed an anxiety-inducing videotape depicting a visit to the dentist. Results indicated that, while both treatments were significantly effective in reducing self-reports of discomfort while viewing the videotape, there was no significant interaction between the type of treatment and preferred cognitive mode. The results were interpreted as indicating that treatment may override individual cognitive styles. Furthermore, the data suggested that the normal individual has the ability to adapt to divergent and non-preferred forms of information processing.  相似文献   
229.
A within-subject comparison was made of the effects of methylphenidate (Ritalin) and response cost in reducing the off-task behavior of two boys, 7 and 8 years of age, who had been diagnosed as having an attentional deficit disorder with hyperactivity. Several dosages of Ritalin (5 to 20 mg/day) were evaluated with the results indicating varying effects of the drug for both children. Response cost (with free-time as the reinforcer) was superior to Ritalin in raising levels of on-task behavior and in improving academic performance.  相似文献   
230.
A multiple-response baseline of four activities was established using gerbils as subjects. When one of the baseline responses was punished (Experiment 1) or restricted (Experiments 2 and 3), only the most probable of the alternative baseline responses increased. The response most likely to follow the punished or restricted responses during baseline sessions was also suppressed during subsequent punishment or response-restriction treatment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号