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ObjectiveThe thymus plays a crucial role in immune system homeostasis. Thymic abnormalities have been reported in many autoimmune diseases, but data for systemic sclerosis (SSc) and rheumatoid arthritis (RA) are sparse. The aim of this study was to evaluate the prevalence and correlates of radiological incomplete involution of the thymus in SSc and RA patients, and in a non-autoimmune group of controls.MethodsAll patients were at least 40 years old: 96 SSc patients (median age 59 years, 80% women) and 65 RA patients (median age 57 years, 88% women) were compared with 32 control individuals (median age 63 years, 62% women). Pulmonary CT-scans performed for lung assessment were available for all individuals. For the purpose of our study, complete involution of the thymus was defined as the absence of a residual thymus or a gland thickness, corresponding to the short axis on the axial slice, of less than 7 mm. We defined incomplete involution of the thymus as a residual thymic tissue more than 7 mm thick.ResultsThe frequency of incomplete thymus involution was significantly higher in SSc and RA patients (respectively 15 and 14%) than in the control group (0%; P < 0.05). Incomplete thymus involution was associated with pulmonary restrictive syndrome in SSc patients, and with biotherapy and an absence of antinuclear antibodies in RA patients.ConclusionOur findings show that two autoimmune diseases, SSc and RA, are associated with incomplete thymus involution.  相似文献   
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Objective: The aim of this study was to evaluate the potential improvements of speech perception and sound quality provided by a multiband single channel noise-reduction algorithm based on the modified Wiener-filter adapted to cochlear implant sound processing. Design: This study was a longitudinal trial with a repeated-measures design. Outcome measures were performed on the first day when the noise reduction feature was provided and after a one month habituation period. Objective measures included pure-tone thresholds and vocal audiometry assessments. Speech perception was measured in quiet and in the presence of two types of noise: a stationary speech shaped noise and a two-talker cocktail noise. Subjective sound quality was assessed using a ten item questionnaire. Study Sample: Thirteen post-lingual deaf adults, experienced users of a cochlear implant system, took part in this study. Results: The noise-reduction algorithm provided a benefit for the perception of speech presented in a stationary speech shaped noise and an overall improvement in subjective sound quality ratings. Conclusions: It was shown that a single channel noise reduction system based on a modified Wiener-filter approach can improve speech in noise perception performance and subjective sound quality in cochlear implant patients.  相似文献   
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This pilot study compared the effects of acute high-intensity intermittent exercise (HIIE) and moderate-intensity continuous exercise (MICE) on post-exercise VO2, fat utilization, and 24-hours energy balance to understand the mechanism of higher fat mass reduction observed after high-intensity interval training in post-menopausal women with overweight/obesity. 12 fasted women (59.5 ± 5.8 years; BMI: 28.9 ± 3.9 kg·m−2) completed three isoenergetic cycling exercise sessions in a counterbalanced, randomized order: (a) MICE [35 minutes at 60%-65% of peak heart rate, HRmax], (b) HIIE 1 [60 × (8-s cycling-12-s recovery) at 80%-90% of HRmax], and (c) HIIE 2 [10 × 1min at 80%-90% of HRmax − 1-min recovery]. Then, VO2 and fat utilization measured at rest and during the 2 hours post-exercise, enjoyment, perceived exertion, and appetite recorded during the session and energy intake (EI) and energy expenditure (EE) assessed over the next 24 hours were compared for the three modalities. Overall, fat utilization increased after exercise. No modality effect or time-modality interaction was observed concerning VO2 and fat oxidation rate during the 2 hours post-exercise. The two exercise modalities did not induce specific EI and EE adaptations, but perceived appetite scores at 1 hour post-exercise were lower after HIIE 1 and HIIE 2 than MICE. Perceived exertion was higher during HIIE 1 and HIIE 2 than MICE, but enjoyment did not differ among modalities. The acute HIIE responses did not allow explaining the greater fat mass loss observed after regular high-intensity interval training in post-menopausal women with overweight/obesity. More studies are needed to understand the mechanisms involved in such adaptations.  相似文献   
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Objective:To determine whether photos or silhouettes are adequate methods for evaluating the esthetic profiles of black subjects and whether black and white evaluators have different preferences for esthetic profiles.Materials and Methods:One photographic record of the profile of a black female patient with accentuated dental bimaxillary dentoalveolar protrusion was randomly selected. The image of the patient''s profile was altered to produce a series of seven photos and seven silhouettes (a total of 14 images) with different lip positions but uniform distances in relation to the esthetic plane created by Ricketts (line E). Fifty black and 50 white lay evaluators were invited to enumerate the photos and silhouettes, produced according to the lip position, in the order in which they considered most esthetically pleasing.Results:The number of preferences found to be within the esthetic norm was slightly higher among the photographs than among the silhouettes; the esthetic profile with a deviation of −2 mm from line E was elected as the most attractive, and the esthetic pattern with a deviation of +6 mm from the normal line E was considered the least attractive. There were no statistically significant differences between the preferences related to the variables race, sex, and educational background.Conclusions:The esthetic attractiveness of the facial profiles of black subjects in photos and silhouettes was evaluated in a similar manner among black and white evaluators. Among both black and white evaluators, the greatest preference was for the slightly concave profile, which was within the limit considered standard.  相似文献   
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