全文获取类型
收费全文 | 3091篇 |
免费 | 1008篇 |
国内免费 | 34篇 |
专业分类
4133篇 |
出版年
2018年 | 34篇 |
2017年 | 31篇 |
2013年 | 209篇 |
2012年 | 64篇 |
2011年 | 88篇 |
2010年 | 118篇 |
2009年 | 203篇 |
2008年 | 102篇 |
2007年 | 130篇 |
2006年 | 85篇 |
2005年 | 97篇 |
2004年 | 123篇 |
2003年 | 116篇 |
2002年 | 91篇 |
2001年 | 136篇 |
2000年 | 67篇 |
1999年 | 100篇 |
1998年 | 89篇 |
1997年 | 67篇 |
1996年 | 106篇 |
1995年 | 94篇 |
1994年 | 96篇 |
1993年 | 85篇 |
1992年 | 108篇 |
1991年 | 97篇 |
1990年 | 95篇 |
1989年 | 89篇 |
1988年 | 74篇 |
1987年 | 61篇 |
1986年 | 54篇 |
1985年 | 49篇 |
1984年 | 49篇 |
1982年 | 52篇 |
1981年 | 43篇 |
1980年 | 44篇 |
1979年 | 41篇 |
1977年 | 31篇 |
1973年 | 39篇 |
1972年 | 44篇 |
1971年 | 44篇 |
1970年 | 29篇 |
1969年 | 32篇 |
1968年 | 58篇 |
1967年 | 38篇 |
1966年 | 48篇 |
1965年 | 41篇 |
1964年 | 81篇 |
1963年 | 74篇 |
1962年 | 49篇 |
1961年 | 40篇 |
排序方式: 共有4133条查询结果,搜索用时 15 毫秒
231.
Behavioral economics of drug self-administration. II. A unit-price analysis of cigarette smoking. 总被引:4,自引:4,他引:0 下载免费PDF全文
W K Bickel R J DeGrandpre J R Hughes S T Higgins 《Journal of the experimental analysis of behavior》1991,55(2):145-154
In behavioral economics, the ratio of response requirement to reinforcer magnitude is referred to as unit price. Previous research with nonhuman subjects has demonstrated that (a) comparable amounts of food are consumed at the same unit price even though different response requirements and reinforcer magnitudes comprise that unit price and (b) increases in unit price decrease food consumption in a positively decelerating fashion. The present study assessed the generality of these findings to the cigarette smoking of 5 human volunteers. During approximately 18 3-hr sessions, various combinations of response requirement (fixed-ratio 200, 400, and 1,600) and reinforcer magnitude (1, 2, and 4 puffs per bout) were arranged. Consumption (i.e., the number of puffs) generally was comparable at the same unit price independent of the response requirement and reinforcer magnitude comprising that unit price. In addition, increasing unit price generally decreased consumption in a positively decelerating fashion. These results extend the generality of the unit-price analysis to human cigarette smoking. Moreover, these results further support the position that reinforcer magnitude and response requirement are functionally equivalent and interact to determine consumption. The concept of unit price, by integrating and summarizing the effects of those two operations, provides a more parsimonious explanation of the results than do separate evaluations of the effects of response requirement and reinforcer magnitude. 相似文献
232.
Economic substitutability of electrical brain stimulation, food, and water. 总被引:1,自引:0,他引:1 下载免费PDF全文
Concurrent variable-ratio schedules of electrical brain stimulation, food, and water were paired in various combinations as reinforcement of rats' lever presses. Relative prices of the concurrent reinforcers were varied by changing the ratio of the response requirements on the two levers. Economic substitutability, measured by the sensitivity of response ratio to changes in relative price, was highest with brain stimulation reinforcement of presses on both levers and lowest with food reinforcement of presses on one lever and water reinforcement of presses on the other. Substitutability with brain stimulation reinforcement of presses on one lever and either food or water reinforcement for presses on the other was about as high as with brain stimulation for presses on both levers. Electrical brain stimulation for rats may thus serve as an economic substitute for two reinforcers, neither of which is substitutable for the other. 相似文献
233.
Articles
Interview with Dr. Peter Rutter, author ofSex in the Forbidden Zone, July 27, 1990 相似文献234.
当代美英法律心理学研究概况 总被引:1,自引:0,他引:1
本文概述了当代美英法律心理学研究的状况,着重论述了它的主要研究领域:证人证言,讯问与供述,法庭心理学,陪审团研究,犯罪心理学,被害人心理学以及司法程序心理学,这些内容对于深化我国的法律心理学研究,具有积极意义。 相似文献
235.
The present study examined the differences in internal and external locus of control and imposter phenomenon among persons
with alcoholic and non-alcoholic parents. The subjects were 48 college students and 21 members of local Adult Children of
Alcoholic groups. The students were further divided into those with alcoholic parents and non-alcoholic parents. The subjects
were administered the following three instruments: the Nowicki-Strickland Internal-External Control Scale for Adults (Nowicki
& Duke, 1973), the Imposter Test (Chance & O’Toole, 1987), and a family history survey. Analysis of locus of control scores
revealed a highly significant (p<.01) difference for externality, with Adult Children being most external and students with
non-alcoholic parents least external. Similarly, internality scores differed significantly (p<.0001), with Adult Children
being least, and the non-alcoholic group being most internally oriented. Analysis of variance for imposter phenomenon revealed
a significant (p<.05) difference among the three groups, with the Adult Children of Alcoholics group having the highest scores
and students with non-alcoholic parents having the lowest. These findings are consistent with the idea that parental alcoholism
interferes with nurturing and consistent reinforcement, and with the development of personal adaptability. 相似文献
236.
Pigeons were exposed to multiple schedules in which an irregular repeating sequence of five stimulus components was correlated with the same reinforcement schedule throughout. Stable, idiosyncratic, response-rate differences developed across components. Components were rank-ordered by response rate; an approximately linear relation was found between rank order and the deviation of mean response rate from the overall mean rate. Nonzero slopes of this line were found for multiple fixed-interval and variable-time schedules and for multiple variable-interval schedules both when number of reinforcements was the same in all components and when it varied. The steepest function slopes were found in the variable schedules with relatively long interfood intervals and relatively short component durations. When just one stimulus was correlated with all components of a multiple variable-interval schedule, the slope of the line was close to zero. The results suggest that food-rate differences may be induced initially by different reactions to the stimuli and subsequently maintained by food. 相似文献
237.
J A Dinsmoor K L Mueller L T Martin C A Bowe 《Journal of the experimental analysis of behavior》1982,38(3):249-263
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
238.
Traditional assumptions that sex-role conformity is positively related to psychological adjustment in young children have not, to date, been examined empirically. Seventy-four preschool children, 37 boys and 37 girls aged 3 to 5, were observed over a 3-month period to determine their frequency of play in male and female sex-typed activities during the free-play period in their classrooms. Teacher ratings on the Kohn and Rosman Symptom Checklist and Social Competence Scale were correlated with individuals' rates of play in male and female preferred activities (M and F scales, respectively). Results indicated that boys' play with male-preferred toys was related to high scores on the aggression/defiance dimension of the Symptom Checklist, while boys who scored highly on play in female-preferred activities received high scores on the Social Competence dimension labeled conforming to classroom rules. For girls, play with malepreferred toys was negatively related to the apathy/withdrawal dimension of the Symptom Checklist. These results do not confirm the hypothesis that sex-typed behavior is positively related to adjustment, and they suggest that for both sexes, play in opposite sex-typed activities may contribute positively to children's social and academic functioning in the classroom.This research was supported in part by Grant No. MH25751-06 from the National Institute of Mental Health, and by a grant from the Programme de Formation de Chercheurs et d'Action Concertée, Ministére de l'Education, Gouvernement du Québec. Portions of this paper were presented at the biennial meeting of the Society for Research in Child Development, Boston, April 1981. 相似文献
239.
As part of a longitudinal study, a control group of 85 children were tested on the WPPSI at 5 years and the WISC-R at 16 years. Educational attainment was also assessed in adolescence. Data are presented illustrating the long-term predictive validity of the WPPSI. The Full Scale IQs on the two tests intercorrelated +0.86. 相似文献
240.