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281.
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The logic of acceptance and rejection (AEL2) is a nonmonotonic formalism to represent states of knowledge of an introspective agent making decisions about available information. Though having much in common, AEL2 differs from Moore's autoepistemic logic (AEL) by the fact that the agent not only can accept or reject a given fact, but he/she also has the possibility not to make any decision in case he/she does not have enough knowledge. 相似文献
283.
Hyperactivity and Learning Deficits in Transgenic Mice Bearing a Human Mutant Thyroid Hormone β1 Receptor Gene
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Michael P. McDonald Rosemary Wong Gregory Goldstein Bruce Weintraub Sheue-yann Cheng Jacqueline N. Crawley 《Learning & memory (Cold Spring Harbor, N.Y.)》1998,5(4):289-301
Resistance to thyroid hormone (RTH) is a human syndrome mapped to the thyroid receptor β (TRβ) gene on chromosome 3, representing a mutation of the ligandbinding domain of the TRβ gene. The syndrome is characterized by reduced tissue responsiveness to thyroid hormone and elevated serum levels of thyroid hormones. A common behavioral phenotype associated with RTH is attention deficit hyperactivity disorder (ADHD). To test the hypothesis that RTH produces attention deficits and/or hyperactivity, transgenic mice expressing a mutant TRβ gene were generated. The present experiment tested RTH transgenic mice from the PV kindred on behavioral tasks relevant to the primary features of ADHD: hyperactivity, sustained attention (vigilance), learning, and impulsivity. Male transgenic mice showed elevated locomotor activity in an open field compared to male wild-type littermate controls. Both male and female transgenic mice exhibited impaired learning of an autoshaping task, compared to wild-type controls. On a vigilance task in an operant chamber, there were no differences between transgenics and controls on the proportion of hits, response latency, or duration of stimulus tolerated. On an operant go/no-go task measuring sustained attention and impulsivity, there were no differences between controls and transgenics. These results indicate that transgenic mice bearing a mutant human TRβ gene demonstrate several behavioral characteristics of ADHD and may serve a valuable heuristic role in elucidating possible candidate genes in converging pathways for other causes of ADHD. 相似文献
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Anna Luzio-lockett 《British Journal of Guidance & Counselling》1998,26(2):209-223
The experience of overseas students on study programmes in a higher educational setting in the UK is explored, in an attempt to identify, from the perspective of the individual, how/why the self might be affected during this 'transitional' period. The adjustment required in this period involves accommodating oneself within the frames of reference of the host culture, entailing an apparent tendency to attempt to squeeze one's identity within pre-established conventions. Language restrictions and other affective and situational factors are seen as being detrimental to academic performance, having a knock-on effect on the 'self-concept', and on the overall educational experience, respectively. This issue should be addressed in the context of guidance and counselling, and academic and personal support, for international students. 相似文献
287.
Giorgio Grossi Anna Åhs Ulf Lundberg 《Integrative psychological & behavioral science》1998,33(3):249-263
The aim of the present study was to examine the association between psychological factors and salivary cortisol secretion
(baseline level, reactivity to laboratory stressors) in a sample of 59 long-term unemployed men and women (mean age 42±10
years). Subjects were divided into four groups according to their basal levels of salivary cortisol as well as their reactivity
to experimental stress (stress level minus baseline): (1) low base/low reactivity; (2) high base/low reactivity; (3) low base/high
reactivity; and (4) high base/high reactivity. The low base/low reactivity group was characterized by significantly higher
somatic anxiety, muscular tension, irritability, and depression (Beck’s Depression Inventory) and lower perceived control
(mastery) than the other groups. The low base/high reactivity group was also characterized by depression and low perceived
control. The high base/low reactivity group was higher in terms of monotony avoidance, Type-A behavior (JAS) and mastery,
but lower in depression. The results indicate that (1) individuals with personality traits reflecting emotional distress are
more vulnerable to exhaustion of the HPA-axis following long-term unemployment and (2) monotony avoidance and Type-A behavior,
at least temporarily, seem to exert a beneficial influence on mental well-being among long-term unemployed individuals. 相似文献
288.
Andy O. J. Giurintano L. Giukintano S. McDonald T. 《Integrative psychological & behavioral science》1975,10(2):85-101
Integrative Psychological and Behavioral Science - This experiment extends Pavlov’s method of contrasts for 8 components of aggression were quantitatively evaluated in 11 freely moving adult... 相似文献
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M McDonald 《The Psychoanalytic quarterly》1971,40(4):618-645