全文获取类型
收费全文 | 9272篇 |
免费 | 373篇 |
国内免费 | 1篇 |
出版年
2020年 | 119篇 |
2019年 | 157篇 |
2018年 | 179篇 |
2017年 | 219篇 |
2016年 | 251篇 |
2015年 | 177篇 |
2014年 | 224篇 |
2013年 | 990篇 |
2012年 | 361篇 |
2011年 | 347篇 |
2010年 | 255篇 |
2009年 | 238篇 |
2008年 | 347篇 |
2007年 | 329篇 |
2006年 | 301篇 |
2005年 | 280篇 |
2004年 | 293篇 |
2003年 | 270篇 |
2002年 | 322篇 |
2001年 | 136篇 |
2000年 | 125篇 |
1999年 | 151篇 |
1998年 | 152篇 |
1997年 | 134篇 |
1996年 | 115篇 |
1995年 | 143篇 |
1994年 | 122篇 |
1993年 | 111篇 |
1992年 | 117篇 |
1991年 | 110篇 |
1990年 | 101篇 |
1989年 | 90篇 |
1988年 | 74篇 |
1987年 | 74篇 |
1986年 | 81篇 |
1985年 | 98篇 |
1984年 | 113篇 |
1983年 | 125篇 |
1982年 | 125篇 |
1981年 | 149篇 |
1980年 | 110篇 |
1979年 | 126篇 |
1978年 | 133篇 |
1977年 | 124篇 |
1976年 | 108篇 |
1975年 | 105篇 |
1974年 | 113篇 |
1973年 | 71篇 |
1972年 | 69篇 |
1969年 | 60篇 |
排序方式: 共有9646条查询结果,搜索用时 15 毫秒
141.
James C. Saunders 《Journal of the experimental analysis of behavior》1969,12(6):951-957
Avoidance conditioning procedures were used to train cats to discriminate intensity differences between successive clicks. The discriminative behavior was applied in a modified method of adjustment to determine a difference limen (DL) for click intensity. The obtained DLs were consistent within and between subjects, and averaged 4.4 db. This value is greater than previously reported intensity DLs for pure tones in cats. 相似文献
142.
143.
James R. Pomerantz Stephen Kaplan Rachel Kaplan 《Attention, perception & psychophysics》1969,6(3):129-132
When single letters were presented for five flashes, with S making a clarity judgment after each exposure, initial potentiation and subsequent satiation effects were found. A processing task and complete prior knowledge led to an increased probability of a “clear” response on the first exposure and to an earlier onset of the satiation effect. The results are discussed in terms of the neural network model underlying this research. 相似文献
144.
James A. Knight M.D. 《Pastoral Psychology》1963,14(9):10-17
Summary Although the title of this essay suggests a comparison of psychoanalysis and Calvinism, I have chosen to compare primarily the two leaders of these movements. On many points they shared similar beliefs. Certain of these areas have been highlighted and discussed briefly: ascetic tendencies, work, religion, concepts of God and of man, actions as symptoms, and predestination and determinism. 相似文献
145.
146.
Individual performances of three rats were examined under a procedure in which steady rates of bar pressing were maintained by conditioned aversive stimulation. Originally neutral visual and auditory stimuli were accompanied by widely and irregularly spaced pulses of shock; they were terminated on a variable-interval schedule by pressing a bar. The contingencies between behavior and shock were also duplicated in a control procedure in which no visual or auditory stimuli were provided. Pressing observed under the control procedure was attributed to differences in the aversiveness of pressing and nonpressing behavior engendered by differences in the incidence of shock following the two classes of behavior. Increased rates with visual and auditory stimuli were attributed to termination of conditioned aversive stimulation. Control rates declined more rapidly than did experimental rates as the mean interval between successive shocks was lengthened; both rates tended to decline when less than 60 sec was allowed as time out from shocks following the successful response. In the control procedure, discrimination between the continuation and discontinuation of the shock series, as measured by relative rates, depended on the relative length of the interval between shocks and the time-out period. Regular warm-up accelerations in rate were noted following an initial delay in responding at the beginning of each session. The length of time required for the warm-up depended on the length of the mean interval between shocks, indicating that exposure to a certain amount of shock was required to establish a supporting state for the observed performance. 相似文献
147.
148.
Drug effects in squirrel monkeys trained on a multiple schedule with a punishment contingency 总被引:1,自引:0,他引:1
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)
H. M. Hanson J. J. Witoslawski E. H. Campbell 《Journal of the experimental analysis of behavior》1967,10(6):565-569
The behavior of four monkeys trained on a multiple schedule was differentially sensitive to selected pharmacological agents. The three components of the multiple schedule were: (1) a variable-interval schedule in which responses were reinforced on the average of once per minute; (2) a concurrent schedule in which every tenth response was reinforced and every fifteenth response, on the average, was shocked; and, (3) a neutral stimulus in the presence of which responses were neither reinforced nor shocked. Pentobarbital, chlordiazepoxide, and meprobamate increased responding during each of the components. Scopolamine and d-amphetamine decreased variable-interval performance, had minimal effects on performance during the concurrent-schedule component, and increased responding in the presence of the neutral stimulus. Chlorpromazine decreased variable-interval responding and had slight effects on the responding during the other two components. 相似文献
149.
150.
James M. Richards Leonard P. Rand Lorraine M. Rand 《Journal of counseling and development : JCD》1967,45(10):987-992
This study examines the geographical distribution of various junior college characteristics. Scores for 6 factors or categories of college characteristics, identified in earlier ACT research, were computed for each of 581 accredited junior colleges. When these junior colleges were classified and analyzed by geographical region, significant differences were found among regions on all 6 factors—Cultural Affluence (or Private Control), Technological Specialization, Size, Age (or Conventionalism), Transfer Emphasis, and Business Orientation (or High Cost). The regional differences are discussed and implications are suggested for research and counseling as well as for junior college planning. 相似文献