全文获取类型
收费全文 | 942篇 |
免费 | 73篇 |
专业分类
1015篇 |
出版年
2020年 | 17篇 |
2019年 | 20篇 |
2018年 | 21篇 |
2017年 | 18篇 |
2016年 | 38篇 |
2015年 | 9篇 |
2014年 | 18篇 |
2013年 | 97篇 |
2012年 | 25篇 |
2011年 | 32篇 |
2010年 | 20篇 |
2009年 | 13篇 |
2008年 | 30篇 |
2007年 | 28篇 |
2006年 | 28篇 |
2005年 | 24篇 |
2004年 | 25篇 |
2003年 | 20篇 |
2002年 | 21篇 |
2001年 | 26篇 |
2000年 | 22篇 |
1999年 | 23篇 |
1998年 | 21篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 13篇 |
1994年 | 18篇 |
1993年 | 12篇 |
1992年 | 18篇 |
1991年 | 26篇 |
1990年 | 16篇 |
1989年 | 10篇 |
1988年 | 16篇 |
1987年 | 13篇 |
1986年 | 13篇 |
1985年 | 13篇 |
1984年 | 19篇 |
1983年 | 11篇 |
1982年 | 17篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1979年 | 13篇 |
1978年 | 16篇 |
1977年 | 20篇 |
1976年 | 8篇 |
1975年 | 7篇 |
1974年 | 10篇 |
1972年 | 13篇 |
1970年 | 6篇 |
1967年 | 7篇 |
排序方式: 共有1015条查询结果,搜索用时 0 毫秒
201.
Assume that each presentation of a signal produces two independent random variable representations and that the ratio of responses on successive trials of a magnitude estimation experiment are proportional to the ratio of a representation from the present trial, which representation is then lost, to the remaining one from the previous trial. The mean response to a particular signal depends on the mean of the representation used, but in general exhibits drift over trials and sequential effects due to the preceeding trial; the mean response ratio does not exhibit drift, but it has a simple form only when there are no sequential effects; however, a modified mean ratio function has a simple form. A model suggested by D. V. Cross is a special case of this one. Simple timing and counting models for the representations fail to exhibit sequential effects, contrary to considerable data. However, data of the authors have suggested a version of the timing model in which the sample size of the representation varies by an order of magnitude depending on how close the signal is to the preceding one; this hypothesis accounts for the observed sequential effects and other aspects of the data. 相似文献
202.
Rats fed a saccharin solution and then rotated on a turntable showed an aversion to the saccharin solution on later testing. In the first experiment, the rats learned to avoid saccharin with delays of as much as 9 hr between drinking the saccharin and the start of rotation. The second experiment showed that the critical determinant of aversiveness of rotation was number of rotations. The rats avoided saccharin as much after rotation at high speeds for short durations as after rotation at low speeds for long durations. 相似文献
203.
Two experiments examined whether phonological receding is an obligatory stage in reading for meaning or whether direct access to a word's semantic representation is the general rule. The first study demonstrated that the time to make a semantic decision about a pair of words was much more delayed by misspelling than was the time to make a phonological one. The second study investigated the effect of varying the syllabic length of a word on reaction time in a category decision task. While reaction time varied with the semantic difficulty of the category decision, it generally proved invariant with respect to syllabic length. It is argued that reading for meaning generally uses a direct route from visual form to semantic representation. 相似文献
204.
Effects on concurrent performances of a stimulus correlated with reinforcer availability 总被引:2,自引:2,他引:0 下载免费PDF全文
A multiple schedule was arranged in which each component consisted of two, concurrent variable-interval schedules of reinforcement. A changeover-key procedure was used, and the components of the multiple schedule were distinguished (initially) by the color of the changeover key. During one component of the multiple schedule, the availability of a reinforcer arranged by one of the variable-interval schedules was marked by an exteroceptive stimulus, provided that that variable-interval schedule was not at the time assigned to the main key. During the other component of the multiple schedule, no reinforcer-correlated stimuli were ever presented. During the latter component of the multiple schedule, the distribution of responses and time for the concurrent variable-interval schedules suggested control by the distribution of reinforcements. During the former component, most main-key responses were emitted on the key in the presence of which reinforcer-correlated stimuli were presented. Changeover rate in the presence of that key color was depressed. The discriminative control over the changeover was easily established and was reversible. 相似文献
205.
206.
207.
208.
Willard P. Green 《Theoretical medicine and bioethics》1988,9(1):33-44
Although we normally have no difficulty with holding individuals accountable for the effects of their actions, we are still confused about holding a health care team accountable. I argue that we can hold teams accountable in the same way that we hold individuals accountable. In constructing this argument, I first examine the nature of a “team,” then look at the consequences of team decision and action, in particular, the problem of synergistic decisionmaking. Finally I relate this philosophical discussion to patient care decisions by teams. 相似文献
209.
This study extends the research on the Circumplex Model to a population of lesbian couples. Instruments consisted of a demographic questionnaire, FACES III, and the Family Satisfaction Scale. Lesbian couples reported significantly higher levels of cohesion, adaptability, and satisfaction than did heterosexual couples. Exceptionally high levels of cohesion and adaptability may help lesbian couples function more successfully in a predominantly heterosexual world. Further, women's socialization may predispose female couples to form more cohesive and adaptable relationships than heterosexual couples. This article also emphasizes the cultural relativity of family norms for studies of lesbian and all minority population couples. 相似文献
210.
Few studies to date have examined time reallocation in naturalistic, multiresponse human repertoires when one or more responses are restricted. For this experiment, free-operant baseline levels of six responses were measured for four autistic children. The high-probability responses were made unavailable, one at a time, such that subjects had access to five, four, three, and two responses in successive restriction conditions. A return to the six-response free-operant baseline condition completed the experiment. Results were compared to predictions made by four time-reallocation models. These results were described accurately only by the selective substitution model. Further analyses examined alternative explanations for the individual reallocation patterns obtained. An expanded selective substitution definition is proposed that may characterize orderly patterns observed in multiresponse repertoires under restriction conditions more accurately than the other existing models. 相似文献