全文获取类型
| 收费全文 | 2351篇 |
| 免费 | 64篇 |
专业分类
| 2415篇 |
出版年
| 2024年 | 10篇 |
| 2023年 | 10篇 |
| 2022年 | 19篇 |
| 2021年 | 31篇 |
| 2020年 | 58篇 |
| 2019年 | 76篇 |
| 2018年 | 99篇 |
| 2017年 | 104篇 |
| 2016年 | 93篇 |
| 2015年 | 69篇 |
| 2014年 | 101篇 |
| 2013年 | 315篇 |
| 2012年 | 122篇 |
| 2011年 | 149篇 |
| 2010年 | 88篇 |
| 2009年 | 83篇 |
| 2008年 | 108篇 |
| 2007年 | 105篇 |
| 2006年 | 80篇 |
| 2005年 | 82篇 |
| 2004年 | 97篇 |
| 2003年 | 73篇 |
| 2002年 | 67篇 |
| 2001年 | 28篇 |
| 2000年 | 24篇 |
| 1999年 | 28篇 |
| 1998年 | 17篇 |
| 1997年 | 18篇 |
| 1996年 | 31篇 |
| 1995年 | 22篇 |
| 1994年 | 23篇 |
| 1993年 | 15篇 |
| 1992年 | 12篇 |
| 1991年 | 10篇 |
| 1990年 | 7篇 |
| 1989年 | 10篇 |
| 1988年 | 7篇 |
| 1987年 | 8篇 |
| 1986年 | 5篇 |
| 1985年 | 9篇 |
| 1984年 | 15篇 |
| 1983年 | 5篇 |
| 1982年 | 9篇 |
| 1981年 | 7篇 |
| 1980年 | 13篇 |
| 1979年 | 9篇 |
| 1978年 | 8篇 |
| 1977年 | 5篇 |
| 1975年 | 9篇 |
| 1973年 | 5篇 |
排序方式： 共有2415条查询结果，搜索用时 0 毫秒
271.
272.
Paulo César Morales Mayer Marcus Bentes de Carvalho Neto Jonathan L. Katz 《Journal of the experimental analysis of behavior》2018,109(2):365-379
The present study examined punishment of responding with histamine injection, and its potential to generate avoidance of punishment. Sprague–Dawley rats were trained under concurrent schedules in which responses on one lever (the punishment lever) produced food under a variable‐interval schedule, and under some conditions intermittent injections of histamine, which suppressed behavior. Responses on a second (avoidance) lever prevented histamine injections scheduled on the punishment lever. After stabilization of punished responding, a variable‐interval 15‐s schedule of cancellation of histamine (avoidance) was added for responding on the second/avoidance lever, without subsequent acquisition of responding on that lever. Progressive decreases in the length of the punishment variable‐interval schedule increased suppression on the punishment lever without increases in response rates on the avoidance lever. Exchanging contingencies on the levers ensured that response rates on the avoidance lever were sufficiently high to decrease the histamine injection frequency; nonetheless response rates on the avoidance lever decreased over subsequent sessions. Under no condition was responding maintained on the avoidance lever despite continued punishing effectiveness of histamine throughout. The present results suggest that avoidance conditioning is not a necessary condition for effective punishment, and confirm the importance of empirical rather than presumed categorization of behavioral effects of stimulus events. 相似文献
273.
Ann Galizio Charles C. J. Frye Jeremy M. Haynes Jonathan E. Friedel Brooke M. Smith Amy L. Odum 《Journal of the experimental analysis of behavior》2018,109(1):210-237
The present study examined persistence and relapse of reinforced behavioral variability in pigeons. Pigeons emitted four‐response sequences across two keys. Sequences produced food according to a lag schedule, in which a response sequence was followed by food if it differed from a certain number of previous sequences. In Experiment 1, food was delivered for sequences that satisfied a lag schedule in both components of a multiple schedule. When reinforcement was removed for one component (i.e., extinction), levels of behavioral variability decreased for only that component. In Experiment 2, food was delivered for sequences satisfying a lag schedule in one component of a multiple schedule. In the other component, food was delivered at the same rate, but without the lag variability requirement (i.e., yoked). Following extinction, levels of behavioral variability returned to baseline for both components after response‐independent food delivery (i.e., reinstatement). In Experiment 3, one group of pigeons responded on a lag variability schedule, and the other group responded on a lag repetition schedule. For both groups, levels of behavioral variability increased when alternative reinforcement was suspended (i.e., resurgence). In each experiment, we observed some evidence for extinction‐induced response variability and for variability as an operant dimension of behavior. 相似文献
274.
275.
Research on the division of cognitive labor has found that adults and children as young as age 5 are able to find appropriate experts for different causal systems. However, little work has explored how children and adults decide when to seek out expert knowledge in the first place. We propose that children and adults rely (in part) on “mechanism metadata,” information about mechanism information. We argue that mechanism metadata is relatively consistent across individuals exposed to similar amounts of mechanism information, and it is applicable to a wide range of causal systems. In three experiments, we show that adults and children as young as 5 years of age have a consistent sense of the causal complexity of different causal systems, and that this sense of complexity is related to decisions about when to seek expert knowledge, but over development there is a shift in focus from procedural information to internal mechanism information. 相似文献
276.
Two experiments examined predictions from two separate explanations for previously observed display effects for communicating low‐probability risks: foreground:background salience and proportional reasoning. According to foreground:background salience, people's risk perceptions are based on the relative salience of the foreground (number of people harmed) versus the background (number of people at risk), such that calling attention to the background makes the risk seem smaller. Conversely, the proportional reasoning explanation states that what matters is whether the respondent attends to the proportion, which conveys how small the risk is. In Experiment 1, we made the background more salient via color and bolding; in contrast to the foreground:background salience prediction, this manipulation did not influence participants' risk aversion. In Experiment 2, we separately manipulated whether the foreground and the background were displayed graphically or numerically. In keeping with the proportional reasoning hypothesis, there was an interaction whereby participants given formats that displayed the foreground and background in the same modality (graphs or numbers, thereby making the proportion easier to form) saw the probability as smaller and were less risk averse than participants given the information in different modalities. There was also a main effect of displaying the background graphically, providing some support for foreground:background salience. In total, this work suggests that the proportional reasoning account provides a good explanation of many display effects related to communicating low‐probability risks, although there is some role for foreground:background salience as well. Copyright © 2018 John Wiley & Sons, Ltd. 相似文献
277.
278.
Creativity is increasingly identified as a key educational outcome at the local, regional, and national levels in several countries. Yet one key issue about the nature of creativity remains controversial: Whether creativity is domain specific or domain general. Resolving this issue would significantly impact the way creativity is identified, nurtured, and assessed in our schools. Three-hundred and fifty-nine undergraduate and graduate students completed measures that assessed their creative achievements in 6 distinct domains. Results based on item response theory models suggested that creativity was domain general, rather than domain specific, and part of the evidence provided by the classical test theory models seemed to favor the domain-specific view. These findings have great implications for researchers and practitioners who aim to assess and promote creativity in schools. 相似文献
279.
Sophie Lebel Ada Y. M. Payne Kenneth Mah Jonathan Irish Gary Rodin Gerald M. Devins 《Psychology, health & medicine》2016,21(5):583-592
Stigma appears to influence emotional distress and well-being in cancer survivors, but cross-cultural differences have been ignored. Previous studies suggest that stigma may be especially relevant for survivors of Asian origin. However, their study designs (e.g. focused on female cancers, qualitative designs, and an absence of comparison groups) limit the strength of this conclusion. We hypothesized that (1) Asian-born Chinese immigrants (AI) would report more perceived cancer-related stigma than Western-born Caucasians (WBC); and (2) the impact of stigma on emotional distress and well-being would be greater in AI as compared to WBC. Head and neck cancer survivors (n = 118 AI and n = 404 WBC) completed measures of well-being, emotional distress, and a three-item indicator of stigma in structured interviews. The majority of respondents (59%) reported one or more indicators of stigma. Stigma correlated significantly with emotional distress (r = .13, p = .004) and well-being (r = ?.09, p = .032). Contrary to our hypotheses, WBCs and AIs did not differ in reported stigma nor did we detect differences in its psychosocial impact. Stigma exerts a deleterious psychosocial impact on head and neck cancer survivors. It did not differ significantly between AI and WBC survivors. 相似文献
280.
Demand for kidneys from deceased donors far outstrips supply. Despite this, there appears to be little research that focuses solely on the experience of waiting for a kidney from a deceased donor. This study uses the qualitative methodology interpretative phenomenological analysis to explore the lives of 10 people on the transplant list, with the aims of illuminating the potential psychological challenges those on the list may face during this time, and providing information to help clinicians more fully support such people in the future. Two themes connected to the experience of waiting – adjustment to the uncertainty of waiting and thinking about receiving a kidney from a living donor – are presented here. Participants describe a sense of confusion and uncertainty around life on the list, and discuss their strategies for dealing with this. Novel complexities around the ambiguous challenge of receiving an organ from a deceased donor are revealed. It is recommended that health care teams provide a forum for this patient group to work through these feelings of confusion and ambiguity. 相似文献