果蔬抗氧化作用研究进展

综述了水果蔬菜抗氧化作用的物质基础及其可能机理和评价方法,不同类型不同品种的果蔬菜氧化活性差异较大,其机理可分为：（1）清除活性氧自由基;（2）增强抗氧化酶活性;（3）阻断脂质过氧化链式反应;（4）减少DNA损伤,果蔬抗氧化作用的物质基础维生素C、维生素E、β－胡萝卜素和微量元素外,还与茄红素、黄酮、花青素、儿茶素等黄酮类化合物密切相关;其抗氧化特性可能是多种营养成分和活性物质综合作用的结果,评价指标可以用总抗氧化活性和氧化－还原当量表示。     

SOD模型化合物（MSOD）对几种蔬菜抗氧化酶活性，叶绿素及脯氨酸含量的影响

用一定浓度的SOD模型化合物(0．015‰)以喷洒方式处理田间几种蔬菜(茄子、三叶芹、辣椒、甘蓝、花菜、黄瓜等)。取其叶片。分别测定了抗氧化酶系统中的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性、叶绿素的含量及细胞内游离脯氨酸的含量．其结果表明，不同的蔬菜品种、同一品种不同生长时期，抗氧化酶系统中的几种酶活性表现不一致．同时也发现MSOD对叶绿素的合成、脯氨酸在细胞内的含量均有一定的影响．     

种养结合循环利用模式下蔬菜的维生素C含量及其抗氧化活性测定

生态环境、作物管理及其他因素如土壤肥力对农产品质量和营养组成有重要影响,为了生产高营养质量的农产品,有必要深入了解这些因素的作用规律.本研究采集来自种养结合循环利用模式下的两种蔬菜青椒和黄瓜,测定了其所含的维生素C含量和抗氧化能力.结果表明,有机种植的蔬菜比常规种植和种养结合循环利用模式的蔬菜合有更多的维生素C.有机产品、常规产品和种养结合模式产品的维生素C含量分别为75.6-9.4 mg/100 g、69.2-8.8 mg/100 g和70.3-9.1 mg/100g.采用DPPH自由基评定两种蔬菜的抗氧化能力,结果以自由基清除率表示.所有结果都显示蔬菜具有很高的自由基清除率,并且与维生素C的含量没有显著的相关关系.     

SOD模型化合物(MSOD)对几种蔬菜抗氧化酶活性,叶绿素及脯氨酸含量的影晌

用一定浓度的SOD模型化合物(0.015‰)以喷洒方式处理田间几种蔬菜(茄子、三叶芹、辣椒、甘蓝、花菜、黄瓜等),取其叶片,分别测定了抗氧化酶系统中的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性、叶绿素的含量及细胞内游离脯氨酸的含量.其结果表明,不同的蔬菜品种、同一品种不同生长时期,抗氧化酶系统中的几种酶活性表现不一致.同时也发现MSOD对叶绿素的合成、脯氨酸在细胞内的含量均有一定的影响.     

槐米与维生素C对运动训练小鼠协同抗氧化作用的研究

通过建立实验模型，研究了槐米与维生素C对运动训练小鼠的协同抗氧化作用．把ICR小鼠随机分为4组，即运动对照组、运动槐米组、运动维生素C组和运动槐米与维生素C组．三组加药组分别每日灌服相同剂量的槐米提取液、维生素C液、槐米与维生素C混合液，3周后测定各组小鼠血清、肝和股四头肌的超氧化物歧化酶(SOD)、丙二醛(MDA)、血红蛋白(Hb)、肝糖原和肌糖原等指标．结果表明，各加药组小鼠血清、肝和股四头肌的SOD活性、Hb、肝糖原、肌糖原含量较运动对照组显著提高，MDA含量明显低于运动对照组．运动槐米与维生素C组较其它3组的结果有更显著的变化趋势，说明槐米与维生素C液对运动训练小鼠的抗氧化能力有良好的协同性。     

野菜硝酸盐、亚硝酸盐含量及抗氧化酶活性分析

测定了水芹、鸭舌草和小藜3种野莱的硝酸盐、亚硝酸盐、维生素C含量和几种抗氧化酶活性,结果表明：水芹和鸭舌草的硝酸盐含量达到了一级标准,小藜却严重超标;3种野莱的亚硝酸盐含量均符合我国制定的无公害蔬菜对亚硝酸盐的限量标准;水芹还具有较高的超氧化物歧化酶（SOD）活性．指出水芹是食用野菜较好的选择,小藜则不宜食用。     

维生素E及其与维生素C,维生素B2联用对小鼠抗氧化体系机能的影响

研究了维生素 E(VE)及其与维生素 C(VC) ,维生素 B2 (VB2 )联用对小鼠机体抗氧化机能的影响。结果表明 ,对小鼠单独饲喂 VC或 VE,VC,VB2 联合饲喂 ,均能显著提高小鼠心、肝组织超氧化歧化酶 (SOD)的活性作用 ;单独饲喂 VE,VC或 VE,VC,VB2 联合饲喂 ,其肝脏丙二醛 (MDA)含量均低于对照组 ,差异非常显著 ,肝脏 SOD/ MDA和 GSH-Px/ MDA比值升高 ;单独饲喂 VC组 GSH-Px/ MDA比值升高尤为明显 ;饲喂VE或 VC,VE,VB2 联合饲喂时 ,小鼠肝组织中谷胱甘肽过氧化物酶 (GSH-Px)活力有增强趋势。这表明 3种维生素联合使用时 ,可产生协同抗氧化、调血脂作用 ,这种作用有利于预防动脉粥样硬化的发生与发展。     

鲢鱼鱼鳞胶原蛋白肽抗氧化作用研究

研究鲢鱼鱼鳞胶原蛋白肽-SCSCP-的抗氧化活性. 依次采用截留分子量为5, 3, 1ku的超滤膜对鲢鱼鱼鳞胶原蛋白肽进行分离分级，通过6种体外抗氧化指标评价各超滤组分抗氧化活性的强弱，分子量小于1ku的SCSCP-IV体外抗氧化活性最强-P＜005- ；氨基酸组成分析表明，SCSCP-IV中总疏水性氨基酸和精氨酸含量均较高，推测可能与其较高的抗氧化活性有关；建立高脂动物模型，考察SCSCP-IV在大鼠体内的抗氧化作用，结果显示SCSCP-IV能显著提高大鼠血清中抗氧化酶超氧化物歧化酶与谷胱甘肽过氧化物酶活力以及降低丙二醛含量-P＜0 05- ，表明SCSCP-IV在大鼠体内具有较好的抗氧化作用；结果表明SCSCP在体外和体内均具有良好的抗氧化活性.     

芦荟对运动训练小鼠脑组织自由基代谢的影响

研究了芦荟对运动训练小鼠脑组织产生的自由基清除效果和保护作用。通过测定小鼠游泳至力竭时间和在安静状态、运动后即刻组和24h恢复组内脑组织中SOD活性、MDA含量和总抗氧化能力，评估了芦荟的抗氧化效果和对脑组织损伤的保护作用．结果表明，在三种不同状态下，芦荟组和对照组比较，SOD活性和总抗氧化能力均有不同程度的升高，MDA含量有所下降，且大部分差异显著。表明芦荟具有较强的清除自由基、抗氧化的效果，可作为一种运动保健食品开发利用．     

五味子酯甲体外抗氧化作用及对大鼠脑组织抗氧化指标的影响

目的观察五味子酯甲(Schisantherin A,SCA)的体外抗氧化作用及对大鼠脑组织中抗氧化指标的影响.方法将12只Wistar大鼠随机分为正常对照组(CON,蒸馏水灌胃)、SCA处理组(1 mg/kg SCA灌胃),连续给药4周,1次/d,0.1 mL/(kg·次).应用Oyaizu法对SCA进行还原活性检测;应用亚油酸-硫氰酸铁法对SCA进行抗氧化活性检测;通过WST-1法、TBA法和分光光度法检测大鼠大脑、小脑和脑干中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量以及谷胱甘肽(GSH)含量.结果体外抗氧化结果显示:在Oyaizu实验中,SCA在浓度为1.25 g/L时其吸光度与维生素E相似;亚油酸-硫氰酸铁法反应48 h后,SCA对亚油酸自氧化抑制作用强于维生素E;动物实验显示:SCA组与CON组比较,大鼠大脑、小脑和脑干中SOD活性和GSH含量显著升高(P0.05),MDA含量显著降低(P0.05).结论 SCA具有体外抗氧化作用,能够增加大鼠脑组织中SOD活性和GSH含量,降低MDA含量.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that