美国广泛发育具有经济效益的富氦无机成因天然气田,如其中富氦氮气田甚至可以含有高达10%的氦。原地和周边地区的基底提供充足的氦源而氮气可来自不同圈层,且通常N_(2)/He(He>0.1%)在5~50之间。但是富氦氮气田在美国独特地质环境之...美国广泛发育具有经济效益的富氦无机成因天然气田,如其中富氦氮气田甚至可以含有高达10%的氦。原地和周边地区的基底提供充足的氦源而氮气可来自不同圈层,且通常N_(2)/He(He>0.1%)在5~50之间。但是富氦氮气田在美国独特地质环境之外是否也有发现还需要进一步的研究。富氦二氧化碳气田中的氦主要也来自壳源且产量可观。科罗拉多高原上的富氦二氧化碳气田均被认为是来源于新生代晚期的岩浆活动,且该地区岩浆岩具有较高的U、Th含量。地下水溶气脱气-再溶解(Groundwater Gas Stripping and Re-dissolution,GGS-R)模型被普遍认为可以合理解释CO_(2)气藏中氮气、氦等惰性气体的聚集成藏机制。具体来说,幔源CO_(2)载体气充注时将溶解在地下水中的大气源惰性气体与壳源惰性气体脱出成藏,并与地下水达到水/气溶解平衡。虽然不同气田的平衡值各有不同,但是科罗拉多高原上的各气田均显示出相似的范围值,即在相应的储层压力和温度下为0~100 cm^(3)水/cm^(3)气。本文系统分析美国无机成因富氦气藏的氦气生成、运移和聚集机制,讨论氦气在经历氦源岩内游离相扩散初次运移后通过水溶相、气容相集流或是多相渗流方式进行的二次运移及由无机成因载体气N_(2)和CO_(2)共同参与的富集成藏机制,既可为我国氦气勘查提供理论认识依据,也可为二氧化碳地质评价和开发利用及安全封存提供参考。展开更多
为全面理解兔肉品质的形成过程,利用偶氮二异丁脒盐酸盐(2,2’-azobis(2-amidinopropane)dihydrochloride,AAPH)的热分解作用生成过氧自由基(ROO·)诱导兔肉肌浆蛋白氧化,通过AAPH处理后兔肉肌浆蛋白中高铁肌红蛋白相对含量、超铁...为全面理解兔肉品质的形成过程,利用偶氮二异丁脒盐酸盐(2,2’-azobis(2-amidinopropane)dihydrochloride,AAPH)的热分解作用生成过氧自由基(ROO·)诱导兔肉肌浆蛋白氧化,通过AAPH处理后兔肉肌浆蛋白中高铁肌红蛋白相对含量、超铁肌红蛋白浓度、羰基含量、总巯基含量以及肌浆蛋白表面疏水性、粒度、浊度和溶解性测定,肌浆蛋白十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)和内源荧光光谱分析,研究ROO·胁迫肌浆蛋白氧化聚集机制。结果表明,随着AAPH浓度的升高,高铁肌红蛋白和超铁肌红蛋白相对含量显著增加(P<0.05),蛋白质羰基含量显著增加(P<0.05),总巯基含量显著下降(P<0.05)。内源荧光光谱和表面疏水性分析结果表明ROO·可以引起肌浆蛋白的去折叠和疏水基团暴露。SDS-PAGE分析结果表明ROO·可以导致肌浆蛋白二硫键交联。此外,随着AAPH浓度的增大,肌浆蛋白粒度和浊度呈现出逐渐增大的趋势,表明ROO·可以引发肌浆蛋白的聚集。疏水相互作用和二硫键交联是ROO·胁迫肌浆蛋白聚集的主要作用力。ROO·不仅可以直接引发肌浆蛋白聚集,还可以通过影响肌红蛋白诱导氧化体系促进肌浆蛋白交联聚集。展开更多
Background/Aims: Hepatitis C virus (HCV) causes a chronic infection that can lead to fibrosis and carcinoma. Immune responses mediated by cytotoxic T lymphocytes (CTLs) could be involved in viral clearance or persiste...Background/Aims: Hepatitis C virus (HCV) causes a chronic infection that can lead to fibrosis and carcinoma. Immune responses mediated by cytotoxic T lymphocytes (CTLs) could be involved in viral clearance or persistence, and therefore in determining the course of the disease. Methods: Intrahepatic and peripheral blood CD8+ T cells were obtained from 32 HCV-chronically infected patients and analysed by flow-cytometry for surface markers of differentiation, IFNγ and TNFα production, degranulation capacity and perforin content, after CD3 triggering. Results were compared with those obtained from 13 patients with a non-viral liver disease. Results: Intrahepatic CD8+ T cells of HCV-infected patiets, despite their phenotype of pre-terminally and terminally differentiated effectors (CCR7- CD45RA- /+ ), are poorly responsive to T cell receptor (TCR)mediated stimulation compared with those obtained from uninfected subjects. This defect correlates with the severity of fibrosis, is more pronounced in patients with ALT< 1.5× N than with ALT >1.5× N U/ml, and is not evident after mitogen stimulation. Conclusions: The present study describes the accumulation of hypo-responsive CD8+ T cells in the liver of patients with chronic HCV infection. Understanding the mechanisms underlying this impairment may be helpful in the design of innovative strategies for HCV treatment.展开更多
文摘美国广泛发育具有经济效益的富氦无机成因天然气田,如其中富氦氮气田甚至可以含有高达10%的氦。原地和周边地区的基底提供充足的氦源而氮气可来自不同圈层,且通常N_(2)/He(He>0.1%)在5~50之间。但是富氦氮气田在美国独特地质环境之外是否也有发现还需要进一步的研究。富氦二氧化碳气田中的氦主要也来自壳源且产量可观。科罗拉多高原上的富氦二氧化碳气田均被认为是来源于新生代晚期的岩浆活动,且该地区岩浆岩具有较高的U、Th含量。地下水溶气脱气-再溶解(Groundwater Gas Stripping and Re-dissolution,GGS-R)模型被普遍认为可以合理解释CO_(2)气藏中氮气、氦等惰性气体的聚集成藏机制。具体来说,幔源CO_(2)载体气充注时将溶解在地下水中的大气源惰性气体与壳源惰性气体脱出成藏,并与地下水达到水/气溶解平衡。虽然不同气田的平衡值各有不同,但是科罗拉多高原上的各气田均显示出相似的范围值,即在相应的储层压力和温度下为0~100 cm^(3)水/cm^(3)气。本文系统分析美国无机成因富氦气藏的氦气生成、运移和聚集机制,讨论氦气在经历氦源岩内游离相扩散初次运移后通过水溶相、气容相集流或是多相渗流方式进行的二次运移及由无机成因载体气N_(2)和CO_(2)共同参与的富集成藏机制,既可为我国氦气勘查提供理论认识依据,也可为二氧化碳地质评价和开发利用及安全封存提供参考。
文摘为全面理解兔肉品质的形成过程,利用偶氮二异丁脒盐酸盐(2,2’-azobis(2-amidinopropane)dihydrochloride,AAPH)的热分解作用生成过氧自由基(ROO·)诱导兔肉肌浆蛋白氧化,通过AAPH处理后兔肉肌浆蛋白中高铁肌红蛋白相对含量、超铁肌红蛋白浓度、羰基含量、总巯基含量以及肌浆蛋白表面疏水性、粒度、浊度和溶解性测定,肌浆蛋白十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)和内源荧光光谱分析,研究ROO·胁迫肌浆蛋白氧化聚集机制。结果表明,随着AAPH浓度的升高,高铁肌红蛋白和超铁肌红蛋白相对含量显著增加(P<0.05),蛋白质羰基含量显著增加(P<0.05),总巯基含量显著下降(P<0.05)。内源荧光光谱和表面疏水性分析结果表明ROO·可以引起肌浆蛋白的去折叠和疏水基团暴露。SDS-PAGE分析结果表明ROO·可以导致肌浆蛋白二硫键交联。此外,随着AAPH浓度的增大,肌浆蛋白粒度和浊度呈现出逐渐增大的趋势,表明ROO·可以引发肌浆蛋白的聚集。疏水相互作用和二硫键交联是ROO·胁迫肌浆蛋白聚集的主要作用力。ROO·不仅可以直接引发肌浆蛋白聚集,还可以通过影响肌红蛋白诱导氧化体系促进肌浆蛋白交联聚集。
文摘Background/Aims: Hepatitis C virus (HCV) causes a chronic infection that can lead to fibrosis and carcinoma. Immune responses mediated by cytotoxic T lymphocytes (CTLs) could be involved in viral clearance or persistence, and therefore in determining the course of the disease. Methods: Intrahepatic and peripheral blood CD8+ T cells were obtained from 32 HCV-chronically infected patients and analysed by flow-cytometry for surface markers of differentiation, IFNγ and TNFα production, degranulation capacity and perforin content, after CD3 triggering. Results were compared with those obtained from 13 patients with a non-viral liver disease. Results: Intrahepatic CD8+ T cells of HCV-infected patiets, despite their phenotype of pre-terminally and terminally differentiated effectors (CCR7- CD45RA- /+ ), are poorly responsive to T cell receptor (TCR)mediated stimulation compared with those obtained from uninfected subjects. This defect correlates with the severity of fibrosis, is more pronounced in patients with ALT< 1.5× N than with ALT >1.5× N U/ml, and is not evident after mitogen stimulation. Conclusions: The present study describes the accumulation of hypo-responsive CD8+ T cells in the liver of patients with chronic HCV infection. Understanding the mechanisms underlying this impairment may be helpful in the design of innovative strategies for HCV treatment.
