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81.
The present study examined the role played by protective factors in moderating the effects of risk factors over bullying and victimization in a sample of 679 male adolescents recruited in Italian high schools. Boys’ involvement in bullying revealed that one in three students has bullied others at least sometimes in the previous three months, and one in six has been victimized at the same rate; victimization decreases with age. The family related risk factor (conflicting parents) was positively associated with bullying and with victimization (together with punitive parenting); the same applied for risk factor related to the individual ways of dealing with problems (emotionally oriented coping skills). Protective factors related to the family context (supportive and authoritative parents) and to the individual (problem solving coping skills) were negatively associated to bullying and victimization. Hierarchical regression analyses revealed a moderating effect of supportive parenting on punitive parenting and on emotionally oriented coping strategies in predicting victimization. Problem solving coping strategies helped buffer the negative impact of emotionally oriented coping strategies over bullying. Implications of results for practitioners and for future studies are addressed.  相似文献   
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Aged rats with extensive prior training on the radial maze retain the capacity for accurate spatial working memory (WM) for at least 3 months without practice. To investigate the temporal limits of this influence of prior experience we compared the reacquisition of spatial WM by a group of experienced 21.5-month-old rats to the original acquisition by naive 3-month-old rats. The aged rats had received 225 radial maze tests between 3 and 11 months of age. Despite 10 months without practice the old rats rapidly reacquired critical performance. Their reacquisition was markedly superior to original learning by the young rats, even when delays as long as 5 h were imposed between the rats' fourth and fifth choices during the daily tests in the eight-arm maze. Additional tests showed that neither young nor old rats employed a response strategy to maintain accurate spatial WM performance. Experience clearly confers long-lived protection against the otherwise deleterious effects of aging on spatial WM, but the mechanism by which this influence arises is unknown.  相似文献   
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Anxiety, nausea and vomiting before, during and after chemotherapy administration were studied in 50 cancer patients. In addition, patient responses to the Autonomic Perception Questionnaire (APQ) and their relation to the anxiety, nausea and vomiting scores was studied. Anticipatory anxiety occurred in 66% and anticipatory nausea in 40% of the patients; 14% showed anticipatory vomiting. The number of patients reporting anxiety decreased to 38% after chemotherapy, whereas nausea and vomiting increased to 47 and 49%, respectively. APQ scores correlated significantly with anxiety and nausea reports during all time periods, but not with the frequency of vomiting.  相似文献   
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J. Clay 《Synthese》1948,7(1):560-574
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The present study examined the association of cardiac autonomic task-induced reactivity and recovery to preclinical atherosclerosis. Thirty-three men and 33 women aged 24-39 years participated in the ongoing epidemiological Cardiovascular Risk in Young Finns study. The authors measured heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) during the mental arithmetic and speech tasks in 1999. Carotid atherosclerosis was assessed by measuring the thickness of the common carotid artery intima-media complex (IMT) with ultrasound in 2001. Higher HR, RSA, and PEP reactivity were associated with lower IMT values even after adjusting for cardiovascular risk factors (lipid levels, obesity, and blood pressure). In addition, better HR recovery after the mental arithmetic task was associated with lower IMT values, and this association persisted after all adjustments. Thus, higher task-induced cardiac autonomic reactivity and better HR recovery were related to less preclinical atherosclerosis. The authors concluded that cardiac pattern of reactivity and quick recovery may be associated with better cardiovascular health, and therefore all reactivity occurring in challenging situations should not automatically be considered as potentially pathological.  相似文献   
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