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Previous research has shown that phobic subjects with low heart rate variability (HRV) are less able to inhibit an inappropriate response when confronted with threatening words compared to phobic subjects with high HRV [Johnsen, B.H., Thayer, J.F., Laberg, J.C., Wormnes, B., Raadal, M., Skaret, E., et al., 2003. Attentional and physiological characteristics of patients with dental anxiety. Journal of Anxiety Disorders, 17, 75–87]. The aim of this study was to evaluate changes in self-reported anxiety when low HRV and high HRV fearful flyers (N = 15) and a matched control group (N = 15) were exposed to flight-related pictures, flight-related sounds or both pictures and sounds. We hypothesized that sounds would be crucial to evoke fear. Also, low HRV fearful flyers were expected to report higher anxiety than high HRV fearful flyers assuming anxiety as their inappropriate response. Decreases on HRV measures were also predicted for a subgroup of phobic participants (N = 10) when confronted with the feared stimuli. Our data supported the hypothesis that sounds are crucial in this kind of phobia. Low HRV fearful flyers reported higher anxiety than high HRV fearful flyers in two out of three aversive conditions. The predicted HRV decreases were not found in this study. Results are discussed in the context of avoidance of exposure-based treatments.  相似文献   
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BACKGROUND: The development of MALDI Imaging Mass Spectrometry is a promising technique in the investigation of biological molecular repertoire. We have pursued an analytical assessment of this technique in its application to proteome analysis. METHODS: A specific statistical method of analysis has been developed to enable data processing in the absence of internal standards, by defining similarity scores. RESULTS: The investigated linear mode MALDI-TOF set-up allows to obtain data variations comprised within the 30% of variation when assaying tissues samples from the same animal, while the 60% of variation was highlighted in the inter-mice series assaying syngenic animals. CONCLUSIONS: This analytical assessment represents the first step of a process that should validate the utilisation of this technique in the clinical practice.  相似文献   
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Massive apoptosis of mesenchymal cells in the septum of the aortico-pulmonary trunk was found in mouse fetuses at stage 14.5 dpc. It was associated with the appearance of cavities in the mesenchymal tissue, presumably due to cell loss, a strong reduction in the extent of lectin PNA staining, and the induction of metallothioneins in specialized mesenchymal cells. Cell loss was spatially restricted to an inner area of the septum and was due to a distinct apoptotic pattern of cells, different from that in the heart wall. These events led to a rapid reduction of the aortico-pulmonary septum as occurs during the late stages of heart morphogenesis. It coincided with the migration of other cell types that invaded the cell-depleted septum, and contributed to the histiogenesis of the mature heart.  相似文献   
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Mutations of the GNE gene are responsible for autosomal recessive hereditary inclusion-body myopathy (HIBM). In this study we searched for the presence of any significant abnormality of alpha-dystroglycan (alpha-DG), a highly glycosylated component of the dystrophin-glycoprotein complex, in 5 HIBM patients which were previously clinically and genetically characterized. Immunocytochemical and immunoblot analysis showed that alpha-DG extracted from muscle biopsies was normally expressed and displayed its typical molecular mass. Immunoblot analysis on the wheat germ lectin-enriched glycoprotein fraction of muscles and primary myotubes showed a reduced amount of alpha-DG in 4 out of 5 HIBM patients, compared to normal and other diseased muscles. However, such altered lectin-binding behaviour, possibly reflecting a partial hyposialylation of alpha-DG, did not affect the laminin binding properties of alpha-DG. Therefore, the subtle changes within the alpha-DG glycosylation pattern, detected in HIBM muscles, likely do not play a key pathogenic role in this disorder.  相似文献   
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The study investigated the use of, attitudes towards, and adherence to motorcycle helmets in a group of adolescents. A random sample of 412 adolescents (14–19 years old) attending randomly selected public secondary classes in Catanzaro (Italy) received a questionnaire consisting of questions on socio-demographics, patterns of motorcycle use, frequency of helmet use, helmet use by adult family members and close friends who are motorcyclists, attitudes towards helmet use and number of traffic-related motorcycle accidents in the last year. A total of 387 adolescents participated. The frequency of self-reported helmet use as a driver of the motorcycle or as the passenger was 34.7% and 33.7% respectively. Routine helmet use was greater for adolescents from households in which at least one family member wore a helmet, for youths who agreed that helmet use should be mandatory, and for those who did not experience an accident in the past year. Regression analysis of the attitude models indicated that the younger the age, the more willing an adolescent would be to believe that helmet use reduced the risk of head injuries and the positive attitude that helmet use should be mandatory was higher in younger adolescents and in those who had no road accident within the past year. A total of 17% reported that they had an accident during the last 12 months of the study period and 30 of them presented motorcycle-related injuries. Conclusion:The development of programmes on helmet use starting as early as primary school is strongly needed.Preliminary results of this study were presented at the 3rd International Conference on Traffic and Transport Psychology, Nottingham, UK, September 5–9, 2004.  相似文献   
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