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In typical development, empathic abilities continue to refine during adolescence and early adulthood. Children and adolescents with autism spectrum disorders (ASD) show deficits in empathy, whereas adults with ASD may have developed compensatory strategies. We aimed at comparing developmental trajectories in the neural mechanisms underlying empathy in individuals with ASD and typically developing control (TDC) subjects. Using an explicit empathizing paradigm and functional magnetic resonance imaging, 27 participants with ASD and 27 TDC aged 12–31 years were investigated. Participants were asked to empathize with emotional faces and to either infer the face’s emotional state (other-task) or to judge their own emotional response (self-task). Differential age-dependent changes were evident during the self-task in the right dorsolateral prefrontal cortex, right medial prefrontal cortex, right inferior parietal cortex, right anterior insula and occipital cortex. Age-dependent decreases in neural activation in TDC were paralleled by either increasing or unchanged age-dependent activation in ASD. These data suggest ASD-associated deviations in the developmental trajectories of self-related processing during empathizing. In TDC, age-dependent modulations of brain areas may reflect the ‘fine-tuning’ of cortical networks by reduction of task-unspecific brain activity. Increased age-related activation in individuals with ASD may indicate the development of compensatory mechanisms.  相似文献   
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The majority of osteoporotic fractures happen in individuals with BMD t-scores in the osteopenic range (?2, 5< t-score <?1). However, widespread use of anti-osteoporotic medication in this group based on t-score alone is not advisable because: 1) the number needed to treat is much higher (NNT?>?100) than in patients with fractured and t-score below ?2,5 (NNT 10?C20); 2)while specific osteoporosis treatments have demonstrated significant reductions of the fracture risk in patients with t-score <?2, 5, the efficacy in patients in the osteopenic range is less well established. Therefore, an osteopenic t-score does not in itself constitute a treatment imperative. Generally, osteopenia has to be associated with either low energy fracture(s) or very high risk for future fracture as assessed with risk calculators like FRAX to warrant specific osteoporosis therapy. Vertebral fractures are now conveniently assessed using lateral x-rays from DXA machines. In the vast majority of cases antiresorptive treatments (mainly hormone replacement therapy and SERMS in younger and bisphosphonates or Denosumab in older women) are the treatments of choice in this group of patients,??only rarely is anabolic therapy indicated.  相似文献   
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Background Visible facial skin condition in females is known to affect perception of age, health and attractiveness. Skin colour distribution in shape‐ and topography‐standardized female faces, driven by localized melanin and haemoglobin, can account for up to twenty years of apparent age perception. Although this is corroborated by an ability to discern female age even in isolated, non‐contextual skin images, a similar effect in the perception of male skin is yet to be demonstrated. Objectives To investigate the effect of skin colour homogeneity and chromophore distribution on the visual perception of age, health and attractiveness of male facial skin. Methods Cropped images from the cheeks of facial images of 160 Caucasian British men aged 10–70 years were blind‐rated for age, health and attractiveness by a total of 308 participants. In addition, the homogeneity of skin images and corresponding eumelanin/oxyhaemoglobin concentration maps were analysed objectively using Haralick’s image segmentation algorithm. Results Isolated skin images taken from the cheeks of younger males were judged as healthier and more attractive. Perception of age, health and attractiveness was strongly related to melanin and haemoglobin distribution, whereby more even distributions led to perception of younger age and greater health and attractiveness. The evenness of melanized features was a stronger cue for age perception, whereas haemoglobin distribution was associated more strongly with health and attractiveness perception. Conclusions Male skin colour homogeneity, driven by melanin and haemoglobin distribution, influences perception of age, health and attractiveness.  相似文献   
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Abstract

Cognitive, or more specifically, psycholinguistic models of sentence processing disorders in agrammatism attempt to specify what types of mental computations (we call them linguistic skills) are affected, at what level of the model, and by what mechanism (e.g. retrieval failure, knowledge loss, capacity limitation). We outline a new, “modular treatments” approach to the rehabilitation of aphasia, using agrammatism as an example. This approach draws from the model-driven analysis an empirically and theoretically defensible enumeration of linguistic skills which are vulnerable to disruption in agrammatism. Specific interventions target each of the vulnerable skills, using designs that aim towards maximal generality in the affected population and that can be standardised for use in the clinic. Such targeted interventions are the “modules” of a complete rehabilitation programme. The clinician chooses which to administer and on what schedule, on a case-by-case basis.  相似文献   
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Context. Cardiac glycosides of plant origin are implicated in toxic ingestions that may result in hospitalization and are potentially lethal. The utility of commonly available digoxin serum assays for detecting foxglove and oleander ingestion has been demonstrated, but no studies have evaluated the structurally similar convallatoxin found in Convallaria majalis (lily of the valley) for rapid laboratory screening, nor has digoxin immune Fab been tested as an antidote for this ingestion. Objective. We aimed to (1) evaluate multiple digoxin assays for cross-reactivity to convallatoxin, (2) identify whether convallatoxin could be detected in vivo at clinically significant doses, and (3) determine whether digoxin immune Fab could be an effective antidote to convallatoxin. Materials and methods. Cross-reactivities of purified convallatoxin and oleandrin with five common digoxin immunoassays were determined. Serum from mice challenged with convallatoxin was tested for apparent digoxin levels. Binding of convallatoxin to digoxin immune Fab was determined in vitro. Results. Both convallatoxin and oleandrin were detectable by a panel of commonly used digoxin immunoassays, but cross-reactivity was variable between individual assays. We observed measurable apparent digoxin levels in serum of convallatoxin intoxicated mice at sublethal doses. Convallatoxin demonstrated no binding by digoxin immune Fab. Conclusion. Multiple digoxin immunoassays detect botanical cardiac glycosides including convallatoxin and thus may be useful for rapid determination of severe exposures, but neutralization of convallatoxin by digoxin immune Fab is unlikely to provide therapeutic benefit.  相似文献   
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