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Stopping during walking, a dynamic motor task frequent in everyday life, is very challenging for ataxic patients, as it reduces their gait stability and increases the incidence of falls. This study was conducted to analyse the biomechanical characteristics of upper and lower body segments during abrupt stopping in ataxic patients in order to identify possible strategies used to counteract the instability in the sagittal and frontal plane. Twelve patients with primary degenerative cerebellar ataxia and 12 age- and sex-matched healthy subjects were studied. Time–distance parameters, dynamic stability of the centre of mass, upper body measures and lower joint kinematic and kinetic parameters were analysed. The results indicate that ataxic patients have a great difficulty in stopping abruptly during walking and adopt a multi-step stopping strategy, occasionally with feet parallel, to compensate for their inability to coordinate the upper body and to generate a well-coordinated lower limb joint flexor–extensor pattern and appropriate braking forces for progressively decelerating the progression of the body in the sagittal plane. A specific rehabilitation treatment designed to improve the ability of ataxic patients to transform unplanned stopping into planned stopping, to coordinate upper body and to execute an effective flexion–extension pattern of the hip and knee joints may be useful in these patients in order to improve their stopping performance and prevent falls.  相似文献   
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Previous evidence on neurotypical adults shows that the presentation of a stimulus allocates the attention to its modality, resulting in faster responses to a subsequent target presented in the same (vs. different) modality. People with Autism Spectrum Disorders (ASDs) often fail to detect a (visual or auditory) target in a stream of stimuli after shifting attention between modalities, possibly because they do not fully switch their attention from one modality to the other. In this study, the performance of a group of high-functioning patients with ASDs and a group of neurotypical controls was compared. Participants were asked to detect a target, auditory or visual, which was preceded, at different temporal intervals (i.e., 150, 600, 1000 ms), by an uninformative cue, either in the same or a different modality. In controls, when the target was visual, the cue modality did not affect performance. Unlike, when the target was auditory, a visual cue produced longer reaction times as compared to when it was auditory. In the ASD group, irrespectively of the modality of the cue, a slowing-down of responses to the target was observed at increasing temporal intervals. The discrepancy of performance is consistent with the ‘over-focused’ theory of sensory processing.  相似文献   
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AimTo investigate the root and canal morphology of maxillary and mandibular permanent molar teeth in a Caucasian population by using Cone Beam Computed Tomography (CBCT).MethodsA total of 596 permanent molars were included. The number of roots, the number of canals per root and the root canal configurations according to the method of Vertucci were recorded.ResultsAlmost all of maxillary first molars (95.7%) had three separate roots; however, 40.3% of mesiobuccal roots had two canals (MB2). Of 157 maxillary second molars, 88.5% had three roots. Among the mesiobuccal roots, 15.1% had two canals. The majority of mandibular molars (100% of first molars, 89.4% of second molars) had two separate roots. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal.ConclusionsCBCT is an efficient method of studying root canal systems.  相似文献   
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Restorative proctocolectomy (RP) is the treatment of choice in patients affected with refractory ulcerative colitis or familial adenomatous polyposis. Surgery in elective settings is often performed in 2 stages, fashioning an ileostomy which is closed 2-3-mo later. It is still debated whether omitting ileostomy could offer advantages in the management of patients undergoing RP.  相似文献   
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Phakomatosis pigmentovascularis is a rare congenital multisystemic disease with variable manifestations where a vascular malformation of the skin is associated with a pigmentary nevus. Ocular involvement includes glaucoma, choroidal hemangioma, and pigmentary alterations that predispose to uveal melanoma. Diagnosis is made on clinical grounds, although recent advances in molecular genetics have better clarified the etiopathogenesis of the condition. The advent of improved imaging techniques such as enhanced depth imaging spectral domain optical coherence tomography has provided new insight into the ocular alterations, enabling better follow-up of patients. We review the ophthalmic manifestations of the disease with an update on etiopathogenesis and current management strategies.  相似文献   
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International Ophthalmology - Prospective, randomised, open-label, comparative study to evaluate efficacy of trehalose/sodium hyaluronate eye drops for post-operative discomfort and tear film...  相似文献   
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