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In humans, the volatile C19-steroids androsta-4,16-dien-3-one (AND) and estra-1,3,5(10),16-tetraen-3-ol (EST) have been shown to modulate autonomic nervous system responses, and to cause hypothalamic activation in a gender-specific manner. Using two conditioning paradigms, the authors here show that pigtail macaques and squirrel monkeys of both sexes were able to detect AND and EST at concentrations in the micromolar and mM range, respectively. Male and female spider monkeys, in contrast, differed markedly in their sensitivity to these two odorous steroids, with males not showing any behavioral responses to the highest concentrations of AND tested and females not responding to the highest concentrations of EST. These data provide the first examples of sex-specific bimodal distributions of olfactory sensitivity in a nonhuman primate species.  相似文献   
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ObjectivesA multi-action plan (MAP) intervention model has been applied to the Italian shooting team in preparation for the London 2012 Olympics to help athletes improve, stabilise, and optimise their performances during practice and competition.DesignA longitudinal design was adopted to assess the intervention effects over two years.MethodsFifteen participants, two female and three male carbine shooters, and five female and five male pistol shooters, took part in the study. First, shooters were requested to accurately and extensively describe their usually optimal sequence of actions for the execution of a single shot from start to follow-through. Second, shooters were asked to identify a small number of the most important core components (three or four) deemed fundamental to optimal performance. Third, performers were engaged in several shooting sessions and asked to assess themselves by rating the quality of each core component. Finally, the most influential core components were further assessed under conditions of increased distress and simulated competition.ResultsCore component ratings were linked to shooting scores classified as optimal or suboptimal. The probability levels of optimal/suboptimal performance associated with the core component ratings were derived using logistical ordinal regression analysis. The full links among core component scores and the full range of shooting scores were also examined through path analysis.ConclusionsFindings highlighted the benefits of using the MAP intervention model in the preparation of elite level shooters.  相似文献   
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The Illness Intrusiveness Rating Scale (IIRS) is a measure designed to assess the impact of illness on various domains of functioning (G. M. Devins, 1994). In anxiety disordered patients, illness intrusiveness ratings are higher than those of chronically ill medical patients, suggesting that the IIRS may have a different underlying structure in a sample of individuals with anxiety disorders. To examine this possibility, IIRS items were submitted to an exploratory and confirmatory factor analysis in 2 samples (total N = 294). These solutions were compared to solutions in chronically ill populations from a previous study. In the exploratory analysis, both a one-factor and a three-factor solution were identified, accounting for 42 and 61% of the variance, respectively. Confirmatory analyses showed adequate similarity between the three-factor structure of the IIRS from a medically ill population and the current three-factor structure, suggesting that elevated IIRS scores in anxiety disordered samples cannot be explained simply by a different structure of the instrument.  相似文献   
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Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases. We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999 to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA) - SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women (70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years). Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous, since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic testing program are necessary.  相似文献   
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Inflammatory bowel disease (IBD) has been associated with social difficulties. Boys with IBD may have increased risk for social problems due to delayed growth and puberty, but gender differences in social functioning have not been investigated. This study examined gender differences in multiple areas of social functioning for adolescents with IBD compared to healthy adolescents. Participants were 92 adolescents 11-17?years (50 with IBD, 42 healthy) and parents who completed questionnaires assessing social functioning. IBD was associated with poorer social functioning in the areas of social competence and social problems. Boys with IBD had worse social competence, with no gender differences for social problems. Gender predicted the use of social contact as a coping strategy, but no significant group differences were found for other areas of social functioning. Adolescents with IBD experience significant social difficulties in some areas, and boys are at risk for poor social competence. However, previously reported social difficulties may not extend to all areas of social functioning.  相似文献   
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This study examined in a Spanish population the developmental pattern of digit span, as an index of one of the components of Baddeley's working memory--the phonological loop. A verbal digit span was administered to 570 participants ranging from 5 to 17 years old. The results indicated that the digit memory span increases until age 17 as opposed to Anglo-Saxon data--where it is established that this span reaches a peak by age 15. Additionally, these results were compared to the performance in the same task of healthy elderly, Alzheimer disease patients, and Frontotemporal dementia patients, examined in a previous study. The analysis shows that the phonological loop is affected by age and not so much by dementias.  相似文献   
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