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91.

Background  

The control of the head movements during walking allows for the stabilisation of the optic flow, for a more effective processing of the vestibular system signals, and for the consequent control of equilibrium.  相似文献   
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Today, many questions persist regarding the causal relationship of gastroesophageal reflux disease (GERD) to promote aspiration and its potential to induce both pulmonary and allograft failure. Current hypotheses, which have identified GERD as a nonimmune risk factor in inducing pulmonary and allograft failure, center on the role of GERD-induced aspiration of gastroduodenal contents. Risk factors of GERD, such as impaired esophageal and gastric motility, may indirectly play a role in the aspiration process. In fact, although impaired esophageal and gastric motility is not independently a cause of lung deterioration or allograft failure, they may cause and or exacerbate GERD. This report seeks to review present research on impaired esophageal and gastric motility in end-stage lung disease to characterize prevalence, etiology, pathophysiology, and current treatment options within this special patient population.  相似文献   
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A meta-analysis was conducted to investigate whether the use of Nd:YAG laser adjunctive to scaling root planing (SRP) could provide additional benefits compared to SRP alone in patients with chronic periodontitis. The meta-analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analysis) statement and the recommendations of the Cochrane Collaboration. A literature search was performed on seven databases, followed by a manual search. Weighted mean differences and 95 % confidence intervals were calculated for the clinical attachment level (CAL), probing depth (PD), and changes in plaque index (PI) and gingival crevicular fluid (GCF). Inter-study heterogeneity was assessed by the I 2 test, and publication bias was analyzed by the visual inspection of the funnel plot for asymmetry, Egger’s regression test, and trim-and-fill method. All outcomes were evaluated from baseline to the end of follow-up. Significant differences in PD and GCF reduction were observed in favor of SRP?+?Nd:YAG; no significant differences were observed in CAL gain or PI change. The findings of this meta-analysis suggest that use of the Nd:YAG laser as an adjunctive therapy to conventional nonsurgical periodontal therapy could potentially provide additional benefits. However, all included studies were not at low risk of bias, and only three studies were included in the meta-analysis. As a result, the evidence is insufficient to support the effectiveness of adjunctive Nd:YAG to SRP. Future long-term well-designed parallel randomized clinical trials are required to assess the effectiveness of the adjunctive use of Nd:YAG laser. These trials should also include microbiological and adverse events analyses.  相似文献   
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Visual neglect results from dysfunction within the spatial attention network. The structural connectivity in undamaged brain tissue in neglect has barely been investigated until now. In the present study, we explored the microstructural white matter characteristics of the contralesional hemisphere in relation to neglect severity and recovery in acute stroke patients. We compared age‐matched healthy subjects and three groups of acute stroke patients (9 ± 0.5 days after stroke): (i) patients with nonrecovered neglect (n = 12); (ii) patients with rapid recovery from initial neglect (within the first week post‐stroke, n = 7), (iii) stroke patients without neglect (n = 17). We analyzed the differences between groups in grey and white matter density and fractional anisotropy (FA) and used fiber tracking to identify the affected fibers. Patients with nonrecovered neglect differed from those with rapid recovery by FA‐reduction in the left inferior parietal lobe. Fibers passing through this region connect the left‐hemispheric analogues of the ventral attention system. Compared with healthy subjects, neglect patients with persisting neglect had FA‐reduction in the left superior parietal lobe, optic radiation, and left corpus callosum/cingulum. Fibers passing through these regions connect centers of the left dorsal attention system. FA‐reduction in the identified regions correlated with neglect severity. The study shows for the first time white matter changes within the spatial attention system remote from the lesion and correlating with the extent and persistence of neglect. The data support the concept of neglect as disintegration within the whole attention system and illustrate the dynamics of structural‐functional correlates in acute stroke. Hum Brain Mapp 35:4678–4692, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
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