羟自由基

Flavone and pyrocatechol were chosento act as model compounds of different structure aspects of flavonoids and theirreactions with α-hydroxyl ethyl peroxyl radical were studied. The rate constants of thereactions of α-hydroxyl ethyl peroxyl radical with flavone and pyrocatechol weredetermined to be 〓 and 〓,respectively.

我们又选择了黄酮体和邻苯二酚作为黄酮类化合物的结构模型，用脉冲辐解的方法研究了它们与α-羟乙基过氧自由基的反应动力学，得到黄酮体和邻苯二酚与α-羟乙基过氧自由基的反应速率分别为〓和〓〓。

N,N '- ditertbutyl nitroxyl radical, 2, 2,6,6- tetramethyl-4 - hydroxyl piperdinehy droxylamine and its nitroxyl radical, as inhibitors of the BPO- initiated copolymerization of styrene (M 1 ) with acrylonitrile (M2 ), at 60℃,has been studied.

研究了二叔丁基羟胺，二叔丁基氮氧自由基，2，2，6，6－四甲基－4－羟基哌啶羟胺和2，2，6，6－四甲基－4－羟基哌啶－1－氧自由基对过氧化苯甲酰60℃引发的苯乙烯（M1）－丙烯腈（M2）共聚合的阻聚行为。

Based on relative literatures,this part has included five resesearch aspects as below.1 Fifteen compounds were isolated and purified by extraction,column chromatography,and their structures were determined on the basis of spectral analysis: acteoside(Ⅰ-1),isoacteoside(Ⅰ-2),crenatoside(Ⅰ-3),cistanoside F(Ⅰ-4),sinapoyl-4-O-β-D-glucoside(Ⅰ-5),adenosine(Ⅰ-6),β-siterol(Ⅰ-7),oleanic acid(Ⅰ-8), succinic acid(Ⅰ-9),caffeic acid(Ⅰ-10),protocatechuic aldehyde(Ⅰ-11),p-hydro xybenzyl alcohol(Ⅰ-12),β-daucosterol(Ⅰ-13),D-galacitol(Ⅰ-14),D-mannitol(Ⅰ-15).Ⅰ-4～15 were obtained from this plant for the first time,andⅠ-6,7,9,and 13 were isolated from Orobanche genus for the first time.2 The scavenging test of DPPH showed that most compounds have comparative antioxidant activity as L-ascorbic acid and part of them show better activity such as the O.coerulescens extract and phenylethanoid glycosides.Acteoside showed potent free radical scavenging effects with a median inhibition concentration of 25.6μg/ml.3 The anti-HBV activities of acteoside,isoacteoside and crenatoside were measured,and all of them showed suppressive activity on the expression of HBsAg and HBeAg in the HepG2.2.15 cell line.

本论文在文献调研基础上对紫花列当化学成分及生物活性进行了研究，并从免疫抗病毒角度探讨紫花列当中特征性成分类叶升麻苷的肝保护作用及其机制。1采用大孔树脂、硅胶和Sephadex LH-20等色谱技术对紫花列当进行系统的植物化学研究，从中分离得到19个化合物，利用UV和NMR等波谱手段及理化性质鉴定了其中的15个化合物，分别为类叶升麻苷(Ⅰ-1)、异类叶升麻苷(Ⅰ-2)、crenatoside(Ⅰ-3)、cistanoside F(Ⅰ-4)、sinapoyl-4-O-β-D-glucoside(Ⅰ-5)、腺苷(Ⅰ-6)、β-谷甾醇(Ⅰ-7)、齐墩果酸(Ⅰ-8)、琥珀酸(Ⅰ-9)、咖啡酸(Ⅰ-10)、原儿茶醛(Ⅰ-11)、对羟甲基苯甲酸(Ⅰ-12)、β-胡萝卜苷(Ⅰ-13)、D-半乳糖醇(Ⅰ-14)和甘露醇(Ⅰ-15除化合物Ⅰ-1、Ⅰ-2和Ⅰ-3外，其余化合物均为首次从该植物中分离得到。2)通过大孔树脂富集该药材有效部位苯乙醇总苷，并采用HPLC测得其所含特征性成分类叶升麻苷的含量可达80%以上。3DPPH自由基清除试验显示紫花列当提取物及其所含的苯乙醇苷类化合物均具有较好的抗氧化能力，其清除DPPH自由基能力接近于抗坏血酸。4采用卡介苗整体致敏、脂多糖离体攻击构建大鼠原代肝细胞免疫性损伤模型，在体外观察类叶升麻苷的保肝作用。

Hydroxylethyl peroxyl radical was chosen to act as a model of lipid peroxyl radical in thekinetic studies of its reaction with several typical flavonoids.

本论文选择了α-羟乙基过氧自由基作为脂质过氧自由基的模拟物，研究了它与几种典型的黄酮类化合物的反应动力学。

Four main parts were included in this dissertation:(1) Precise measurement of Gvalues of hydrogen peroxide in the reactions of flavonoids with superoxide anion andα-hydroxy ethyl peroxyl radicals;(2) Kinetic studies of the reactions of typicalflavonoids with α-hydroxy ethyl peroxyl radicals;(3) HPLC-MS analysis of theproducts after γ-irradiating rutin ethanol solution saturated with air, a reactionmechanism was proposed;(4) Preliminary investigation on the reaction between rutinand peroxynitrite.

本论文的内容主要包括四部分：(1)黄酮类化合物在与超氧阴离子自由基以及α-羟乙基过氧自由基反应的过程中生成的过氧化氢G值的准确测定；(2)几种典型的黄酮类化合物与α-羟乙基过氧自由基的反应动力学研究：(3)空气饱和芦丁乙醇溶液经γ-辐照后产物的HPLC-MS分析及反应机理推测；(4)对芦丁与过氧亚硝酸盐的反应做了初步的探索。

Release of ferric iron catalyzed the conversion of super oxide and hydrogen peroxide to the more toxic hydroxyl radical which has been shown to be an important mediator of ischemic brain edema.

三价铁释放，促使过氧化物和过氧化氢转化成毒性更大的羟自由基，这是缺血性脑水肿的一种更重要的递质。

In a complex series of reactions, one of which is promoted by ultraviolet light, the iron reacts with both the hydrogen peroxide and some of the water itself to produce powerful oxidising agents known as hydroxyl radicals.

在一系列复杂的反应中，有一种是在紫外线的推动下，铁与过氧化氢和一些水本身发生反应，产生强大的氧化剂叫做羟自由基。

Methods 18 Sprague-Dawley rats were randomly divided into 3 groups: the normal group, the GI/R group and the Ⅰ-postC group. The gastric mucosal damage index and the inhibitory effect of gastric mucosa on hydroxyl free radicals as well as the expression of xanthane oxidase, malondialdehyde and superoxide dismutase were measured respectively. Results The gastric mucosa was markedly injured after GI/R.

健康SD大鼠18只，随机分为3组，即对照组、缺血／再灌注组、缺血后处理组，分别检测大鼠胃黏膜损伤指数及胃黏膜组织抑制羟自由基能力、黄嘌呤氧化酶、丙二醛、超氧化物歧化酶含量。

And the Honeysuckle's leaves extracts have hydroxy free radical scavenging effects as well. The re-extract by ethyl acetate has obviously scavenging activity when its concentration is 1 mg/mL.

抗氧化实验结果表明，金银花叶乙醇提取物具有一定的抗羟自由基氧化活性，其中乙酸乙酯萃取物在1mg/mL的低浓度下就显示出了较好的效果。

The apple polyphenol extracts had stronger reducing capacity, antioxidant activity on lipid-peroxidation, and scavenging effects on hydroxyl radical, superoxide anion radical and nitroso than ascorbic acid at the same concentration.

按照以上工艺制备的苹果多酚提取物具有较强的还原能力和抗脂质过氧化活性，并对羟自山基、超氧阴离子自由基及亚硝基具有很强的清除作用，且优于同浓度的维生素C。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。