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排序方式: 共有3583条查询结果,搜索用时 15 毫秒
1.
Exhaled nitric oxide in children with allergic rhinitis: A potential biomarker of asthma development
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G Salviati R Betto D Danieli-Betto E Biasia M Serena M Mini G Scarlato 《Neurology》1986,36(5):693-697
We evaluated the isoform composition of heavy and light chains of myosin in single muscle fibers from patients with Duchenne dystrophy, myotonic dystrophy, or polymyositis. In all myopathic muscles, there was an increase in the proportion of intermediate fibers which, by analysis of myosin isoforms, fell into two subpopulations, one that contained both fast and slow myosin and another that contained myosin molecular hybrids. The increased proportion of intermediate (or transitional) fibers suggests changes in the equilibrium between fast and slow motor units. These changes could result from regeneration and subsequent maturation of fibers or from direct transformation of mature fibers of one type into the opposite. 相似文献
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Mark R. Beauchamp Albert V. Carron Serena McCutcheon Oliver Harper 《Annals of behavioral medicine》2007,33(2):200-206
Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One
limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics
of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise
classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants
found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization
theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard
exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed
at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers. 相似文献
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Martin C. Robson MD ; Diane M. Cooper PhD RN ; Rummana Aslam MD ; Lisa J. Gould MD PhD ; Keith G. Harding MBChB MRCGP FRCS ; David J. Margolis MD MSCE PhD ; Diane E. Ochs RN ; Thomas E. Serena MD ; Robert J. Snyder DPM ; David L. Steed MD ; David R. Thomas MD ; Laurel Wiersema-Bryant RN BC ANP 《Wound repair and regeneration》2008,16(2):147-150
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Francesco Martino Pasquale Pignatelli Eliana Martino Francesco Morrone Roberto Carnevale Serena Di Santo Barbara Buchetti Lorenzo Loffredo Francesco Violi 《Journal of the American College of Cardiology》2007,49(19):1974-1981
OBJECTIVES: The aim of the study was to analyze the behavior of oxidative stress and its interplay with CD40L, a protein that is implicated in atherosclerosis, in hypercholesterolemic children. BACKGROUND: Oxidative stress has been suggested to play a major role in premature atherosclerosis. METHODS: Forty-one children with hypercholesterolemia (mean age 9.28 +/- 0.5 years) and 40 children with normocholesterolemia (mean age 9.02 +/- 0.69 years) were matched for gender and age. Within each group, children were classified as having or not having a family history of cardiovascular disease. Serum levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, and plasma levels of soluble CD40L (sCD40L) were measured in each child. In a subgroup of children with high (n = 8) or normal (n = 8) levels of serum cholesterol, platelet p38 mitogen-activated protein (MAP) kinase phosphorylation, a protein involved in the activation of nicotinamide adenine dinucleotide phosphate oxidase, was determined. RESULTS: Children with hypercholesterolemia had higher values of 8-OHdG and sCD40L compared with control subjects (0.55 +/- 0.06 ng/ml vs. 0.21 +/- 0.02 ng/ml, p < 0.001 and 0.55 +/- 0.04 ng/ml vs. 0.19 +/- 0.03 ng/ml, p < 0.001, respectively). A significant correlation between 8-OHdG and sCD40L was observed in children with high (r = 0.676, p < 0.001) or normal (r = 0.878, p < 0.001) levels of cholesterol. Children with a family history of cardiovascular disease tended to have higher values of 8-OHdG and sCD40L, but the difference was not significant. Analysis of platelet p38 MAP kinase showed that it was phosphorylated more in children with hypercholesterolemia compared with control subjects (36.8 +/- 5.8 AU vs. 8.0 +/- 4.5 AU, p < 0.001 respectively). CONCLUSIONS: Children with hypercholesterolemia have an early increase of oxidative stress that may be responsible for up-regulation of CD40L and potentially predispose to premature atherosclerosis. 相似文献
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Effect of interferon-alpha therapy on epitope-specific cytotoxic T lymphocyte responses in hepatitis C virus-infected individuals. 总被引:4,自引:0,他引:4
Simona Vertuani Martina Bazzaro Guido Gualandi Fabiola Micheletti Mauro Marastoni Cinzia Fortini Alessandro Canella Michele Marino Roberto Tomatis Serena Traniello Riccardo Gavioli 《European journal of immunology》2002,32(1):144-154
The majority of hepatitis C virus (HCV)-infected individuals fail to resolve the infection and become chronically infected despite the presence of HCV-specific CTL responses directed to different HCV-derived peptide antigens. Only a minority of individuals is able to clear the virus by mounting efficient CTL responses early after acute infection, but at present it is not clear whether viral clearance is associated with CTL responses of defined specificity. To elucidate those responses associated with improvement of the disease, we analyzed CTL responses to 16 different HLA-A2-presented, HCV-derived epitopes in 12 chronically infected patients, 14 chronically infected patients treated with interferon-alpha, and in one patient with acute symptomatic disease. We show here that the majority of chronically infected individuals present CTL responses directed to an NS4-derived peptide antigen (amino acids 1789-1797). Treated patients presented stronger HCV-specific CTL responses and therapy-induced changes in CTL target choice. In particular, 13 out of 14 individuals responded to an NS3-derived epitope (amino acids 1073-1081). By longitudinal analysis we show that five individuals responding to IFN-alpha therapy with decreases in alanine aminotransferase levels presented a strong CTL activity directed to the NS3-derived epitope. One patient that spontaneously resolved the infection presented a generally strong CTL activity specific for HCV-derived epitopes with a dominant response to the NS3-derived peptide antigen. This suggests that CTL responses directed to this NS3-derived antigen may be beneficial for the control of HCV infection. Improvement of these responses may represent a therapeutic intervention in chronic HCV infection. 相似文献
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Vitamin E affects cell death in adult rat dentate gyrus 总被引:1,自引:0,他引:1
Ferri P Cecchini T Ciaroni S Ambrogini P Cuppini R Santi S Benedetti S Pagliarani S Del Grande P Papa S 《Journal of neurocytology》2003,32(9):1155-1164
We have previously reported the presence of dying cells in the granule cell layer (GCL) of adult rat dentate gyrus (DG), where neurogenesis occurs. In particular, we found that cell death in the GCL increased in vitamin E deficiency and decreased in vitamin E supplementation. These findings were regarded as related to changes in neurogenesis rate, which in turn was influenced by vitamin E availability; a neuroprotective effect of vitamin E on cell death was also proposed. In order to verify this latter hypothesis, we have studied cell death in all layers of DG in vitamin E-deficient and vitamin E-supplemented rats and in control rats at different ages, using TUNEL and nick translation techniques. The phenotype of TUNEL-positive cells was characterized and the existence of dying BrdU-positive cells was investigated. Dying cells with neuronal phenotype were observed throughout the DG in all experimental groups. The number of TUNEL-positive cells decreased from juvenile to adult age. A higher number of TUNEL-positive cells in vitamin E-deficient rats and a lower number in vitamin E-supplemented rats, with respect to age-matched controls, were found; moreover, in these groups, TUNEL-positive cells had a different percentage distribution in the different layers of the DG. Our results confirm the occurrence of cell death in DG, demonstrate that cell death affects neuronal cells and support the hypothesis that the effect of vitamin E on cell death is not related to neurogenesis. 相似文献