全文获取类型
收费全文 | 52370篇 |
免费 | 1980篇 |
国内免费 | 17篇 |
出版年
2019年 | 614篇 |
2018年 | 840篇 |
2017年 | 906篇 |
2016年 | 907篇 |
2015年 | 616篇 |
2014年 | 798篇 |
2013年 | 3858篇 |
2012年 | 1496篇 |
2011年 | 1612篇 |
2010年 | 966篇 |
2009年 | 954篇 |
2008年 | 1395篇 |
2007年 | 1360篇 |
2006年 | 1267篇 |
2005年 | 1136篇 |
2004年 | 1120篇 |
2003年 | 1019篇 |
2002年 | 1094篇 |
2001年 | 1626篇 |
2000年 | 1555篇 |
1999年 | 1165篇 |
1998年 | 610篇 |
1997年 | 500篇 |
1996年 | 484篇 |
1992年 | 943篇 |
1991年 | 894篇 |
1990年 | 918篇 |
1989年 | 898篇 |
1988年 | 863篇 |
1987年 | 843篇 |
1986年 | 874篇 |
1985年 | 941篇 |
1984年 | 749篇 |
1983年 | 688篇 |
1982年 | 569篇 |
1981年 | 522篇 |
1979年 | 869篇 |
1978年 | 623篇 |
1977年 | 538篇 |
1976年 | 549篇 |
1975年 | 735篇 |
1974年 | 815篇 |
1973年 | 816篇 |
1972年 | 699篇 |
1971年 | 631篇 |
1970年 | 608篇 |
1969年 | 688篇 |
1968年 | 803篇 |
1967年 | 708篇 |
1966年 | 713篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
221.
Two experiments replicated Ekman and Friesen's finding of an expression that signals contempt across cultures. The subjects, from West Sumatra, Indonesia, were members of a culture that differs in a number of ways from Western cultures. In one experiment the subjects judged photographs of Japanese and American faces, both males and females, which showed many different emotions. There was very high agreement about which expressions signaled contempt in preference to anger, disgust, happiness, sadness, fear, or surprise. In a second experiment the Indonesian subjects judged expressions shown by members of their own culture, and again there was very high agreement about which expression signals contempt.This study was supported by a grant from the National Institute of Mental Health (MH 41100). Paul Ekman's work is also supported by a Research Scientist Award from the National Institute of Mental Health (MH 06092). Karl G. Heider's work was supported by a grant from the National Institute of Mental Health (MH 38221). We are grateful to Maureen O'Sullivan for her many helpful comments on this report. 相似文献
222.
Picture-pointing auditory and reading comprehension tests were administered to anomic and conduction aphasics. Subjects responded to active sentences of the present progressive form. The possible errors which a subject could make on these experimental tasks included failure to correctly interpret noun order, number, or lexical meaning. Both groups made significantly more correct responses than error responses. Of their error responses, noun-order errors significantly exceeded number and lexical errors for which no differences were observed. When compared with results previously obtained for agrammatic Broca's aphasics, no differences in the pattern of errors were identified. These results are discussed relative to current theories of syntactic processing and for the mechanisms which account for these syntactic comprehension deficits following aphasia. 相似文献
223.
224.
The ability of right-brain-damaged (RBD) subjects to correctly insert a word into a well-formed stimulus sentence was tested. Subjects also performed three evaluative tasks designed to establish their degree of general cognitive impairment. The performance of RBD subjects on these tasks was compared to that of left-brain-damaged (LBD) and non-brain-damaged (NBD) subjects. Although RBD subjects outperformed LBD subjects on the language-related evaluative tasks, the RBD group was significantly more impaired on a subset of the insertion task. This subset included items which required reassignment of the syntactic status of elements in the stimulus sentence in order for the insertion to be carried out. The results of this study permit refinement of the common characterization of RBD individuals as rigid in their interpretation of meaning and indicate right-hemisphere involvement in aspects of the grammar previously thought to be inaccessible to it. 相似文献
225.
Knowledge and beliefs regarding the consequences of cigarette smoking and their relationships to smoking status in a biracial sample 总被引:3,自引:0,他引:3
R C Klesges G Somes R W Pascale L M Klesges M Murphy K Brown E Williams 《Health psychology》1988,7(5):387-401
The purpose of this investigation was to evaluate carefully smoking-related knowledge and beliefs and their relationships to smoking status in a large, heterogeneous sample of smokers and nonsmokers in two settings: (a) a large, biracial southern city and (b) a small midwestern community. Participants were 611 (198 male, 413 female) adult respondents to a random-dialing telephone survey in Fargo, North Dakota (n = 200), and Memphis, Tennessee (n = 411). Each participant was given the Smoking Attitudes Survey, which assesses generalized health beliefs as well as health-related problems associated with smoking. Participants' knowledge of smoking-associated diseases (e.g., lung cancer) and of diseases not associated with smoking (e.g., kidney stones) was assessed. Stepwise regression analysis of composite knowledge scores revealed four independent predictors of the health consequences of smoking: education, race, smoking status, and income. Smokers, compared to nonsmokers, reported less knowledge related to the health consequences of smoking, were more likely to be male, were less concerned with the health consequences of smoking, and were more concerned about the health consequences of cholesterol. The best predictor of smokers who had never attempted cessation was their greater concern over weight control when compared to smokers with a history of smoking cessation attempts. The results are discussed in terms of smoking prevention and intervention efforts. 相似文献
226.
Previous studies suggest that anxiety and/or depressed mood are associated with recurrence of genital herpes lesions. The present study sought to extend the assessment of factors associated with genital herpes and to investigate the impact of psychological therapy on features of the disorder. Sixteen genital herpes patients received 5 weeks of either structured discussion or cognitive restructuring (CR) therapy in a group format. Measures of attitude about herpes, global coping, distress, loneliness, health locus of control, and recurrence frequency were administered at pretreatment, posttreatment, and 3 months follow-up. Patients also made daily reports during the 5 weeks of treatment from which information was extracted regarding their herpes symptoms, dysphoria, anxiety, and ongoing coping process. Therapy did not produce the expected reductions in reported distress or loneliness. The CR procedure, however, was associated with reduced frequency of lesion recurrence at follow-up. Avoidant coping was associated with lower recurrence rates, and loneliness scores were associated with higher recurrence rates. Prospective data indicated that recurrences were preceded by elevated anxiety that was independent of prodromal symptoms. These results provide support for the general proposals that psychological factors influence health status and that psychological intervention may reduce disease recurrence. 相似文献
227.
Contextually relevant aspects of meaning 总被引:2,自引:0,他引:2
G McKoon R Ratcliff 《Journal of experimental psychology. Learning, memory, and cognition》1988,14(2):331-343
A series of six experiments investigated whether inferences about contextually relevant aspects of meaning were encoded into memory during reading. In all the experiments, subjects studied short paragraphs. Then, test sentences were presented that expressed relevant aspects of meaning that had not been explicitly stated in the paragraphs. For example, for a paragraph about searching for the correct color to paint a picture of a tomato, a relevant aspect of meaning would be that tomatoes are red. The test sentences were presented either immediately following the relevant paragraph or after a delay. With immediate testing, it was argued that the facilitation obtained in verification latency could result from processes occurring either when the context was read or when the test sentence was verified. With delayed testing, evidence was found to support the hypothesis that contextually relevant aspects of meaning are incorporated into the memory representation of the paragraph, but such evidence was obtained only when the retrieval environment encouraged the use of newly learned information in the decision process on the test sentence. 相似文献
228.
The vocationally-indecisive individual presents a major counselling problem. The theory and research behind career indecision is discussed and a counselling approach based on identity formation is outlined. Four identity statuses — Identity Achievements, Foreclosures, Identity Diffusions, and Moratoriums — are described and counselling approaches for each are explored. 相似文献
229.
J E Mazur 《Journal of the experimental analysis of behavior》1988,49(1):37-47
In a series of conditions, pigeons chose between 1.5 s and 3 s of access to grain, each preceded by some delay. The delay that preceded the small reinforcer was constant throughout a condition. The delay that preceded the large reinforcer was increased or decreased a number of times each session in order to estimate an "indifference point," a delay at which the subject chose each alternative about equally often. The experiment was designed to determine whether variations in any of four features of this adjusting-delay procedure would systematically alter the estimated indifference points. The four features were the total trial duration, the number of center-key responses necessary to begin a trial, the number of choice trials that preceded each change in the adjusting delay, and step size--the size of each increment and decrement in the delay. Manipulation of the first three features had no systematic effects on the indifference points. As step size was increased from 0.5 s to 6 s, within-session variability of the adjusting delay steadily increased, and the 6-s step size produced larger indifference-point estimates for some subjects. The results suggest that, within certain limits, these procedural features can be altered without affecting the indifference-point estimates, but that the use of a large step size can distort the estimates. Some theoretical implications of the relative constancy of indifference points across these procedural variations are discussed. 相似文献
230.
Self-control in mentally retarded adolescents: choice as a function of amount and delay of reinforcement.
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)
Three severely mentally retarded adolescents were studied under discrete-trial procedures in which a choice was arranged between edible reinforcers that differed in magnitude and, in some conditions, delay. In the absence of delays the larger reinforcer was consistently chosen. Under conditions in which the smaller reinforcer was not delayed, increasing the delay to delivery of the larger reinforcer decreased the percentage of trials in which that reinforcer was chosen. All subjects directed the majority of choice responses to the smaller reinforcer when the larger reinforcer was sufficiently delayed, although the value at which this occurred differed across subjects. Under conditions in which the larger reinforcer initially was sufficiently delayed to result in preference for the smaller one, progressively increasing in 5-s increments the delay to both reinforcers increased percentage of trials with the larger reinforcer chosen. At sufficiently long delays, 2 of the subjects consistently chose the larger, but more delayed, reinforcer, and the 3rd subject chose that reinforcer on half of the trials. These results are consistent with the findings of prior studies in which adult humans responded to terminate noise and pigeons responded to produce food. 相似文献