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Primary vertebral osteosarcoma is a rare type of osteosarcoma, differing from the appendicular forms by an incidence peak occurring at a higher age and a poorer prognosis, due to the difficulties of the surgical treatment. We present five cases of histologically proven primary vertebral osteosarcomas followed in our institution between 2004 and 2012. They allow to illustrate some essential radiologic features, useful to evoke this rare entity.  相似文献   
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BackgroundMuch interest has been focused on nutritional treatment of sarcopenia, loss of muscle mass and performance associated to aging; however, its benefits are unclear.ObjectiveTo analyze the relevance of nutritional treatment of sarcopenia and assess the effects of supplementation on muscle mass and function within the aged population.MethodsWe searched Medline and the Cochrane Library for controlled trials published between 1991 and 2012. We have assessed the quality, type of intervention, the cohort used, the way muscle mass was measured, and the outcomes of the various studies.ResultsWe have included 17 studies, with a total of 1287 patients, aged between 65 and 85 on average. An improvement in muscle mass was proven, whether measured with bioelectrical impedance analysis or dual energy x-ray absorptiometry, and an improvement in strength was also proven.ConclusionNutritional supplementation is effective in the treatment of sarcopenia in old age, and its positive effects increase when associated with physical exercise. The main limitation of this treatment is lack of long-term adherence. A healthy diet associated with a physically active lifestyle and possibly with aerobic exercise are the basis of healthy aging, which is the aim of all doctors treating aged people must seek.  相似文献   
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Commercial α-cellulose was compression-molded to produce 1A dog-bone specimens under various operating conditions without any additive. The resulting agromaterials exhibited a smooth, plastic-like surface, and constituted a suitable target as replacement for plastic materials. Tensile and three-points bending tests were conducted according to ISO standards related to the evaluation of plastic materials. The specimens had strengths comparable to classical petroleum-based thermoplastics. They also exhibited high moduli, which is characteristic of brittle materials. A higher temperature and higher pressure rate produced specimens with higher mechanical properties while low moisture content produced weaker specimens. Generally, the strong specimen had higher specific gravity and lower moisture content. However, some parameters did not follow the general trend e.g., thinner specimen showed much higher Young’s Modulus, although their specific gravity and moisture content remained similar to control, revealing a marked skin-effect which was confirmed by SEM observations.  相似文献   
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Parasitology Research - Lagochilascariosis is an emerging parasitic disease limited to the American continent, caused by nematodes of the genus Lagochilascaris. Its life cycle is heteroxenous,...  相似文献   
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Background  

Granulocytes generally exert protective roles in the central nervous system (CNS), but recent studies suggest that they can be detrimental in experimental autoimmune encephalomyelitis (EAE), the most common model of multiple sclerosis. While the cytokines and adhesion molecules involved in granulocyte adhesion to the brain vasculature have started to be elucidated, the required chemokines remain undetermined.  相似文献   
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A female patient, 20 years of age, is reported with a history characterized by developmental and psychomotor delay, and during grammar-school period increasing learning problems, ritualistic behaviours and social withdrawal. Subsequently, challenging and autistic-like behaviours became prominent. The patient showed mild facial dysmorphisms, long thin fingers with bilateral mild short V metacarpals, and hyperlaxity of the joints. Neuropsychiatric examination disclosed obsessive, ritualistic behaviours and vague ideas of reference. Neuropsychological assessment demonstrated mild intellectual disability, mental inflexibility and incongruent affect. MRI-scanning of the brain showed no relevant abnormalities. Genome wide SNP array analysis revealed a 1.2 Mb de novo interstitial microdeletion in 4q25 comprising 11 genes, that was considered to be causative for the developmental delay, perseverative cognitive phenotype and dysmorphisms.To the authors knowledge, this is the first report of a de novo 4q25 microdeletion that presents with a specific behavioural phenotype.  相似文献   
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