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Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury.  相似文献   
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With the aim of presenting the processes governing the Laser-Induced Periodic Surface Structures (LIPSS), its main theoretical models have been reported. More emphasis is given to those suitable for clarifying the experimental structures observed on the surface of wide bandgap semiconductors (WBS) and dielectric materials. The role played by radiation surface electromagnetic waves as well as Surface Plasmon Polaritons in determining both Low and High Spatial Frequency LIPSS is briefly discussed, together with some experimental evidence. Non-conventional techniques for LIPSS formation are concisely introduced to point out the high technical possibility of enhancing the homogeneity of surface structures as well as tuning the electronic properties driven by point defects induced in WBS. Among these, double- or multiple-fs-pulse irradiations are shown to be suitable for providing further insight into the LIPSS process together with fine control on the formed surface structures. Modifications occurring by LIPSS on surfaces of WBS and dielectrics display high potentialities for their cross-cutting technological features and wide applications in which the main surface and electronic properties can be engineered. By these assessments, the employment of such nanostructured materials in innovative devices could be envisaged.  相似文献   
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ObjectiveThis study aims to evaluate the diagnostic accuracy of a new CT sign in order to define or exclude a malignant aetiology of bowel obstruction.Materials and methodsCT scans of 137 patients affected by bowel obstruction were reviewed. Colonic obstruction occurred in 47 (34%) cases, small bowel obstruction in 90 (66%). Neoplastic aetiology was found in 42 cases (31%), while in the remaining 95 (69%) obstruction was caused by non-neoplastic conditions. Definitive diagnosis was surgically confirmed in all patients. CT images were evaluated searching for bowel obstruction's signs and for the presence of the “protruding lips” sign on the proximal surface of stenosis, which is represented by the evidence of a protrusion within the dilated loop.ResultsThe sign was found in 31 (23%) cases, all of neoplastic origin. When malignant obstruction was diagnosed, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy values of the described sign were 74%, 100%, 100%, 90% and 92%, respectively.ConclusionsThe “protruding lips” sign represents an alteration to be searched when bowel obstruction is diagnosed by CT examination. Its evidence correlates to a malignant condition with a 100% probability and when it is not found, the probability of a non-neoplastic condition is 90%.  相似文献   
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Gardner syndrome, a variant of familial adenomatous polyposis, is an autosomal dominant genetic disease characterized by the combined presence of multiple intestinal polyps and extraintestinal manifestations. The extraintestinal manifestations include multiple osteomas, connective tissue tumors, thyroid carcinomas, and hypertrophy of the pigmented epithelium of the retina. Osteoma is a benign neoplasm of bone tissue characterized by slow continuous growth that usually affects the long bones and cranial bones and is a major symptom for Gardner syndrome. The authors report the extraintestinal lesions affecting the maxillofacial regions in 2 male patients (father and son) with Gardner syndrome. The presurgical planning and surgical management of these lesions are described.  相似文献   
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