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131.
Recent research has indicated that the pro-inflammatory cytokines, particularly interleukin-1beta (IL-1beta), can affect learning and memory. We injected male Sprague-Dawley rats with IL-1beta (1.0, 3.0, or 6.0 microg/kg, i.p.) or saline vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. No effect of IL-1beta at any dose was observed in the number of escape responses across the 4-h session. However, subjects treated with the two lower doses (1.0 and 3.0 microg/kg) of IL-1beta performed more avoidance responses during the final hour of the 4-h session than the other two groups. Subjects treated with the highest dose of IL-1beta (6.0 microg/kg) did not differ from controls. Results are discussed in terms of the possible mechanisms behind the IL-1beta-induced enhancement of learning, as well as the observed dose-response relationship.  相似文献   
132.
Exposure to electrical current via industrial or residential accidents or lightning strikes is a serious and growing concern in today's medical community. The sequelae that result are referred to as electrical injury (EI) or lightning injury (LI). The relevant principles in electricity are reviewed with particular attention given to their damaging capabilities on the body. Specific neuropsychological, psychiatric, and neurological signs and symptoms as well as objective measures of psychological and neuropsychological functioning and brain imaging in victims of EI and LI, are reviewed from past research. Important issues relevant to researchers in the field are discussed. Finally, the role that neuropsychology might play in this area is outlined.  相似文献   
133.
This essay describes how contemporary medical education and pastoral care share historical roots, confront similar pressures and objectives in the formation of future professionals, and address common concerns in the area of bioethics. The essay concludes with a summary of ideas regarding the present and future relationship between medical education and pastoral care. The essay is dedicated to the memory of David P. Rogers, M.D., whose vision of medical education and medical practice embodied a rare passion for justice.  相似文献   
134.
In considering the influences of microsystems on adolescent substance use, familial and peer contexts have received the most extensive attention in the research literature. School and neighborhood settings, however, are other developmental contexts that may exert specific influences on adolescent substance use. In many instances, school settings are organized to provide educational services to students who share similar educational abilities and behavioral repertoires. The resulting segregation of students into these settings may result in different school norms for substance use. Similarly, neighborhood resources, including models for substance use and drug sales involvement, may play an important role in adolescent substance use. We briefly review literature examining contextual influences on adolescent substance use, and present results from two preliminary studies examining the contribution of school and neighborhood context to adolescent substance use. In the first investigation, we examine the impact of familial, peer, and school contexts on adolescent substance use. Respondents were 283 students (ages 13 to 18) from regular and special education classrooms in six schools. Although peer and parental contexts were important predictors of substance use, school norms for drug use accounted for variance in adolescent use beyond that explained by peer and parental norms. Data from a second study of 114 adolescents (mean age = 15) examines neighborhood contributions to adolescent substance use. In this sample, neighborhood indices did not contribute to our understanding of adolescent substance use. Implications for prevention are presented.  相似文献   
135.
This exploratory study uses qualitative methods to focus on the largely unexamined role of the grandfather and to examine men's experiences as grandfathers. We gathered information through both surveys and individual interviews to explore men's feelings and attitudes toward the grandfather role. Of the 51 grandfathers that completed a survey, 20 participated in interviews. Our examination of the data collected reveals the life lessons men teach their grandchildren. The grandfathers in this study expressed strong desires for purposeful involvement in their grandchildren's lives and indicated desires for transferring values to grandchildren and teaching interpersonal relationships. Through this involvement, they educate through life experiences and serve as mentors for their grandchildren. We suggest that this mentoring role makes a positive contribution to the lives of grandchildren and to the identity of grandfathers.  相似文献   
136.
Belief revision theory concerns methods for reformulating an agent's epistemic state when the agent's beliefs are refuted by new information. The usual guiding principle in the design of such methods is to preserve as much of the agent's epistemic state as possible when the state is revised. Learning theoretic research focuses, instead, on a learning method's reliability or ability to converge to true, informative beliefs over a wide range of possible environments. This paper bridges the two perspectives by assessing the reliability of several proposed belief revision operators. Stringent conceptions of minimal change are shown to occasion a limitation called inductive amnesia: they can predict the future only if they cannot remember the past. Avoidance of inductive amnesia can therefore function as a plausible and hitherto unrecognized constraint on the design of belief revision operators.  相似文献   
137.
Emergent research identifies cultural tightness-looseness as an important factor for understanding cross-national outcome differences during the coronavirus pandemic. Because perceived tightness-looseness can be measured as an individual-level difference rather than a nation-level difference, and because tightness-looseness may shift during large-scale crises, we investigated whether such shifts occurred early in the coronavirus pandemic in both China (a relatively tight nation, n = 3642) and the U.S. (a relatively loose nation, n = 3583) across three cohorts. Tightness increased across cohorts in China and reduced across cohorts in the U.S. These changes transmitted corresponding indirect effects whereby compliance and institutional trust (scientific and government) about the pandemic were increased in China across cohorts, but decreased in the U.S. across cohorts. These patterns extend advice that national governments can increase compliance and trust via “tightening” by cautioning against norm-setters signaling the reverse (that norms about compliance are loose) given the outcomes observed in the U.S. samples.  相似文献   
138.
We tested a strategy to encourage cigarette smokers to think more frequently about the negative consequences of smoking, reasoning that increased thought might lead to greater worry and motivation to quit. College students who smoked daily were randomly assigned to one of three conditions in which they wore watches for one week that sounded an alarm randomly four times each day. When alerted, the students read one of eight cards that either had a written statement about studying (control condition), a statement about the negative effects of smoking behaviour (text condition), or a negative smoking statement accompanied by a picture (e.g., a blackened lung; image condition). Measures collected at week's end revealed that the smoking cards had no effects on perceived risk, but they increased worry and reports of intrusive thoughts, and had a small but reliable effect on plans to quit. Correlational data also supported the relationship between worry and motivation to quit, and we discuss the possible benefits of “normal” worrying and strategies for capitalising on the worry–motivation relationship to encourage smokers to abandon cigarettes.  相似文献   
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