822 resultados para Xiao.
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Priming to Ag can inhibit subsequent induction of an immune response to a new epitope incorporated into that Ag, a phenomenon referred to as original antigenic sin. In this study, we show that prior immunity to a virus capsid can inhibit subsequent induction of the IFN-gamma effector T cell response to a novel CD8-restricted antigenic epitope associated with the virus capsid. Inhibition does not involve Ab to the virus capsid, as it is observed in animals lacking B cells. CD8-restricted virus-specific T cell responses are not required, as printing to virus without CTL induction is associated with inhibition. However, IL-10(-/-) mice, in contrast to IL-10(+/+) mice, generate CD8 T cell and Ab responses to novel epitopes incorporated into a virus capsid, even when priming to the capsid has resulted in high titer Ab to the capsid. Furthermore, capsid-primed mice, unable to mount a response to a novel epitope in the capsid protein, are nevertheless able to respond to the same novel epitope delivered independently of the capsid. Thus, inhibition of responsiveness to a novel epitope in a virus-primed animal is a consequence of secretion of IL-10 in response to presented Ag, which inhibits local generation of new CD8 IFN-gamma-secreting effector T cells. Induction of virus- or tumor Ag-specific CD8 effector T cells in the partially Ag-primed host may thus be facilitated by local neutralization of IL-10.
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Understanding the mechanism of liquid-phase evaporation in a three-phase fixed-bed reactor is of practical importance, because the reaction heat is usually 7-10 times the vaporization heat of the liquid components. Evaporation, especially the liquid dryout, can largely influence the reactor performance and even safety. To predict the vanishing condition of the liquid phase, Raoult's law was applied as a preliminary approach, with the liquid vanishing temperature defined based on a liquid flow rate of zero. While providing correct trends, Raoult's law exhibits some limitation in explaining the temperature profile in the reactor. To comprehensively understand the whole process of liquid evaporation, a set of experiments on inlet temperature, catalyst activity, liquid flow rate, gas flow rate, and operation pressure were carried out. A liquid-region length-predicting equation is suggested based on these experiments and the principle of heat balance.
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We introduce a new wavelet transform within the framework of the local fractional calculus. An illustrative example of local fractional wavelet transform is also presented.
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We perform a comparison between the fractional iteration and decomposition methods applied to the wave equation on Cantor set. The operators are taken in the local sense. The results illustrate the significant features of the two methods which are both very effective and straightforward for solving the differential equations with local fractional derivative.
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We present systems of Navier-Stokes equations on Cantor sets, which are described by the local fractional vector calculus. It is shown that the results for Navier-Stokes equations in a fractal bounded domain are efficient and accurate for describing fluid flow in fractal media.
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In this paper, we discuss the mathematical aspects of the Heisenberg uncertainty principle within local fractional Fourier analysis. The Schrödinger equation and Heisenberg uncertainty principles are structured within local fractional operators.
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The local fractional Poisson equations in two independent variables that appear in mathematical physics involving the local fractional derivatives are investigated in this paper. The approximate solutions with the nondifferentiable functions are obtained by using the local fractional variational iteration method.
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The local fractional Poisson equations in two independent variables that appear in mathematical physics involving the local fractional derivatives are investigated in this paper. The approximate solutions with the nondifferentiable functions are obtained by using the local fractional variational iteration method.
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The local fractional Burgers’ equation (LFBE) is investigated from the point of view of local fractional conservation laws envisaging a nonlinear local fractional transport equation with a linear non-differentiable diffusion term. The local fractional derivative transformations and the LFBE conversion to a linear local fractional diffusion equation are analyzed.
TUBERCULOSIS INFECTION MIGHT INCREASE THE RISK OF INVASIVE CANDIDIASIS IN AN IMMUNOCOMPETENT PATIENT
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Deep Candida infections commonly occur in immunosuppressed patients. A rare case of a multiple deep organ infection with Candida albicansand spinal tuberculosis was reported in a healthy young man. The 19-year-old man complained of month-long fever and lower back pain. He also had a history of scalded mouth syndrome. Coinfection with Mycobacterium tuberculosis and Candida albicans was diagnosed using the culture of aspirates from different regions. Symptoms improved considerably after antifungal and antituberculous therapy. This case illustrates that infection with tuberculosis might impair the host's immune system and increase the risk of invasive candidiasis in an immunocompetent patient.
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Dissertation presented to obtain the Ph.D degree in Biology
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Abstract: INTRODUCTION: To provide information for cervical cancer screening and vaccination in Henan province, China, the distribution of human papillomavirus (HPV) was analyzed. METHODS: The HPV genotypes were detected using gene array and flow-through hybridization. RESULTS: Overall, 38.1% (1,536/4,033) of the women were human papillomavirus deoxyribonucleic acid (HPV DNA) positive. The prevalence of high-risk HPV types was 32.4%. HPV 16 was the most prevalent genotype (8.9%), followed by HPV 52 (5.8%) and HPV 58 (4.4%). CONCLUSIONS: The data support close surveillance of women for cervical cancer screening, and HPV prophylactic vaccines including HPV16, HPV 52, and HPV 58 might offer greater protection in this area.
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We demonstrate the first example of silicon nanowire array photocathodes coupled with hollow spheres of the emerging earth-abundant cobalt phosphide catalysts. Compared to bare silicon nanowire arrays, the hybrid electrodes exhibit significantly improved photoelectrochemical performance toward the solar-driven H2 evolution reaction.
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FUNDAMENTO: O programa de biogênese mitocondrial no coração parece apresentar remodelação adaptativa após estresse biomecânico e oxidativo. Os mecanismos adaptativos que protegem o metabolismo do miocárdio durante a hipóxia são coordenados, em parte, pelo óxido nítrico (NO). OBJETIVO: Observar a biogênese mitocondrial e expressão do óxido nítrico sintase (NOS) em corações de cardiopatia congênita com cianose; discutir a resposta mitocondrial à hipóxia crônica do miocárdio. MÉTODOS: Foram investigados 20 pacientes com defeitos cardíacos cianóticos (n = 10) ou acianóticos (n = 10). Foram estudadas amostras do miocárdio na via de saída ventricular direita, tomadas durante a operação. A análise morfométrica de mitocôndrias foi realizada por microscopia eletrônica de transmissão. A relação mtDNA/nDNA foi determinada com PCR em tempo real. Os níveis de transcrição da subunidade I da citocromo c oxidase (COXI), coativador-1α do receptor γ ativado por proliferador de peroxissoma (PGC-1α), o fator respiratório nuclear 1 (NRF1), e fator de transcrição mitocondrial A (Tfam) foram detectados por reação em cadeia da polimerase via transcriptase reversa (RT-PCR) ativado por fluorescência em tempo real. Os níveis proteicos de COXI e nNOS, iNOS e eNOS foram medidos por técnica de Western Blot. RESULTADOS: A densidade volumétrica mitocondrial (Vv) e a densidade numérica (Nv) foram significativamente elevadas em pacientes com cianose, em comparação com a cardiopatia congênita acianótica. MtDNA elevada e suprarregulação dos níveis de COXI, PGC-1 α, NRF1 e Tfam mRNA foram observadas em pacientes cianóticos. Os níveis de proteína de COXI e eNOS foram significativamente maiores no miocárdio de pacientes cianóticos que nos de acianóticos. Os níveis de transcrição do PGC-1α se correlacionam com os níveis de eNOS. CONCLUSÃO: A biogênese mitocondrial é ativada no miocárdio da via de saída ventricular na cardiopatia congênita com cianose, que poderia ser a resposta adaptativa à hipóxia crônica e possivelmente envolve suprarregulação da eNOS. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0)