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61.
62.
The muscular dystrophies are a large and heterogeneous group of neuromuscular disorders that can be classified according to the mode of inheritance, the clinical phenotype and the molecular defect. To better understand the pathological mechanisms of dysferlin myopathy we compared the protein-expression pattern in the muscle biopsies of six patients with this disease with six patients with limb girdle muscular dystrophy 2A, five with facioscapulohumeral dystrophy and six normal control subjects. To investigate differences in the expression levels of skeletal muscle proteins we used 2-DE and MS. Western blot or immunohistochemistry confirmed relevant results. The study showed specific increase expression of proteins involved in fast-to-slow fiber type conversion (ankyrin repeat protein 2), type I predominance (phosphorylated forms of slow troponin T), sarcomere stabilization (actinin-associated LIM protein), protein ubiquitination (TRIM 72) and skeletal muscle differentiation (Rho-GDP-dissociation inhibitor ly-GDI) in dysferlin myopathy. As anticipated, we also found differential expression of proteins common to all the muscular dystrophies studied. This comparative proteomic analysis suggests that in dysferlin myopathy (i) the type I fiber predominance is an active process of fiber type conversion rather than a selective loss of type II fibers and (ii) the dysregulation of proteins involved in muscle differentiation further confirms the role of dysferlin in this process.  相似文献   
63.
A new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction cell has been designed and experimentally demonstrated. By computer simulations we show how bending the grading of the band gap in the i-layer contributes to the enhancement of the carrier collection, improving the fill factor and efficiency. The differences observed between experiments and simulations are studied using Rutherford Backscattering Spectrometry (RBS). The results highlight weak points during the deposition process, whose control enables us to bring together experimental and computational results.  相似文献   
64.
Methamphetamine (MA) dependence is associated with deficits in episodic verbal memory, but the cognitive mechanisms underlying such impairments are not known. The authors evaluated a component process model of episodic verbal memory in 87 persons with MA dependence (MA+) and 71 demographically similar non-MA-using controls (MA-). Compared with MA- controls, MA+ participants demonstrated deficient overall learning, free recall, and utilization of semantic clustering, as well as higher rates of repetitions and intrusions. No between-groups differences were evident on measures of serial clustering, retention, or recognition discrimination. Taken together, these findings indicate that MA dependence is associated with deficient strategic (i.e., executive) control of verbal encoding and retrieval, which is consistent with the sequelae of MA-related prefronto-striatal circuit neurotoxicity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
Twenty-five early-onset relapsing-remitting multiple sclerosis patients (12 women and 13 men) with mild disability were compared with 25 matched controls in a dichotic listening (DL) test under nonforced and forced attentional-shift conditions. Patients showed left ear impairment and no left ear advantage in the forced-left condition. Four corpus callosum (CC) regions were measured in patients on a rnidsaggital magnetic resonance imaging scan. The right ear score was negatively correlated whereas the left ear score was positively correlated with CC regions (significant only for the nonforced condition). Moreover, in men, the correlations with DL scores were linked mainly to the splenium and posterior isthmus, and in women, they were stronger for anterior isthmus and posterior body. An inverse correlation between months of disease evolution and CC area was found only in women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Administration for 7 days of an enteral diet that is naturally deficient in polyamines strikingly reduces the preneoplastic changes observed in the intestines of adult Wistar rats previously treated with the carcinogen 1,2-dimethylhydrazine. On the contrary, supplementing the enteral diet with spermidine favors preneoplastic development. The effects of the low-polyamine diet included a 40% decline in the putrescine content of the intestinal mucosa, a significant decrease in the turnover rate of the epithelial cells from the crypts to villus tip in the ileum, and a 2-fold reduction in the number of abnormal colonic crypts. The experimental data support the view that it might be of interest to control the dietary intake of polyamines in the clinical management of cancer patients.  相似文献   
67.
A method is developed for analyzing sudden injection dye (tracer) curves in order to obtain the distribution of first passage times in the mammalian circulation. The moments of the distribution yield useful quantities such as circulating blood volume. The method involves the use of Liouville-Neumann series. The calculation of the first passage time distribution (FPD) also requires a deconvolution through the use of Fourier transforms, but the calculation of moments does not.  相似文献   
68.
Essential hypertension is considered a multifactorial trait resulting from a combination of environmental and genetic factors. The angiotensin II type 1 receptor mediates the vasoconstrictor and growth-promoting effects of Ang II. The A1166C polymorphism of the AT1 receptor gene may be associated with cardiovascular phenotypes, such as high arterial blood pressure, aortic stiffness, and increased cardiovascular risk. We investigated the association between this A1166C polymorphism and hypertension in hypertense and normotense subjects from San Luis (Argentina) by mismatch PCR-RFLP analysis. Hypertense patients exhibited significant increases in lipid related values and body mass index. The frequency of occurrence of the C1166 allele was higher among patients with hypertension (0.19) than in the control group (0.06). No significant association was found between this polymorphism and essential hypertension in the study population, although the AC genotype prevalence was higher in patients with hypertension and positive family history of hypertension (32%) than in control subjects (12%). Patients with the A1166C polymorphism exhibited higher levels of serum total cholesterol, LDL-cholesterol and BMI than in control subjects. Taken together the genotype and biochemical parameters and considering the restrictive selection criteria used, the present results suggest a correlation between AT1 A1166C gene polymorphism and risk of cardiovascular disease.  相似文献   
69.
70.
The tensile performance of coated woven fabrics under multiaxial loads is examined in the present study. Two groups of experiments were conducted to investigate the influences of the configuration of the fabric specimen and the loading speed on the multiaxial tensile properties of the fabrics. The configuration of the specimen for the multiaxial tensile tests is identified as gear‐shape with large arm widths. A loading speed of lower than 20 mm/min is suggested to obtain the tensile properties of the coated woven fabrics under multiaxial loads. The tensile performances of coated woven fabrics under uni‐, bi‐, and multiaxial loads were compared. We found that the tensile performances under bi‐ and multiaxial loads are much better than those under uniaxial loads. Therefore, for the application of the coated woven fabrics in lightweight structures, biaxial or multiaxial loading conditions will be necessary. Experiments on the specimens with an initial crack in the center under multiaxial loads show that, by comparison with other loading directions, the tensile properties in warp direction of the coated woven fabrics play an important role in the failure performance and crack propagation under multiaxial loads. To eliminate the dependence on the mechanical properties in warp direction, the balance of the two principle directions of coated woven fabrics should be improved. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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