连翘叶提取物对油脂抗氧化作用的研究

用乙醇提取连翘叶中的抗氧化物质,以猪油为底物,用烘箱储藏法测定POV值和酸价.结 果表明,连翘叶提取物可以降低POV值和酸价,具有抗氧化作用.     

连翘叶提取物对实验小鼠的降脂保肝作用研究

选用ICR健康小鼠,通过复制高脂血症模型,研究连翘叶提取物(extracts fromForsythiasuspenseleaves,FSE)对高脂血症小鼠血液、肝脏指标的影响.结果显示:FSE可降低高脂血症小鼠血清中总胆固醇(total cholester-ol,TC)、甘油三酯(total triglyceride,TG)、低密度脂蛋白(low-density lipoprotein,LDL-C)水平,升高高密度脂蛋白(high-density lipoprotein,HDL-C)水平;此外,FSE还可降低肝脏中TC、丙二醛(malordiaolehyde,MDA)含量,提高超氧化物歧化酶(superoxide dismutase,SOD)活性.以上结果提示,FSE可改善高脂血症小鼠血脂紊乱现象,对其肝脏也具有一定的保护作用.     

连翘叶提取物对力竭及恢复小鼠血清SOD,LDH活性和MDA含量的影响

选用ICR健康小鼠,通过复制力竭运动模型,研究连翘叶提取物(extract from Forsythia suspensa leaves,FSE)对力竭及恢复小鼠血清超氧化物歧化酶(superoxide dismutase,SOD)、乳酸脱氢酶同工酶(isozymes of lactate dehydrogenase,LDH)活性和丙二醛(malordiaolehyde,MDA)含量的影响.结果显示,FSE能提高力竭运动状态下小鼠血清SOD的活性,减少力竭及恢复状态下血清MDA的生成,并可降低LDH总活性.以上结果表明,FSE具有保护骨骼肌细胞、预防与降低运动后骨骼肌微损伤的发生以及促进损伤恢复的作用.     

连翘叶中苷类成分Ⅱ的体外抗氧化作用研究

研究连翘叶中苷类成分Ⅱ(FSGⅡ)的体外抗氧化作用。用水杨酸法研究FSGⅡ清除.OH的效果,连苯三酚自氧化法研究FSGⅡ清除O2.-的效果,硫代巴比妥酸法测定小鼠组织及肝线粒体、微粒体中丙二醛含量,分光光度法测定小鼠红细胞溶血和肝线粒体膨胀程度,研究FSGⅡ的抗氧化效果。结果表明FSGⅡ可以清除.OH和O2.-,抑制.OH所致丙二醛的产生,减少红细胞溶血,减轻肝线粒体的膨胀程度。FSGⅡ具有明显的体外抗氧化的作用。     

酶辅助超声波法提取连翘叶总黄酮工艺

采用酶辅助超声波法提取连翘叶总黄酮,在超声波条件固定的情况下,研究了酶解时间、酶解液pH值、酶解温度和酶用量对连翘叶总黄酮的影响。获得的优化条件为:酶解时间1.5 h,酶解温度40℃,酶量3 mg/g,最适pH值为5.0。在此条件下测定的连翘叶总黄酮含量为(26.53±0.68)%。试验结果表明:酶辅助超声波法提取连翘叶总黄酮是一种行之有效的方法。     

贯叶连翘的提取与除鞣工艺研究

采用乙醇热回流法提取贯叶连翘的有效成分,用改良明胶法除去鞣质,优选贯叶连翘的提取与除鞣工艺.以金丝桃苷和干浸膏收率为指标,确定贯叶连翘的提取工艺为粉碎成粗粉,用质量分数80%乙醇10倍量,热回流提取2次,每次0.5 h;以金丝桃苷和除鞣效果为指标,确定除鞣工艺为提取液减压回收乙醇至无醇味,并浓缩至1 g/mL,放冷,调pH为4~5,在搅拌条件下每毫升药液滴加质量分数10%明胶溶液的量为0.25 g,再加乙醇至醇质量分数为80%.冷藏过夜,过滤,沉淀弃之,以除去鞣质.实验证明,此法既可提取出贯叶连翘的有效成分,又可除去鞣质,以改善口感,提高纯度.     

紫外分光光度法测定连翘总苯乙醇苷的含量

采用紫外分光光度法,建立了连翘中总苯乙醇苷的含量测定方法,考察了连翘中木脂素、黄酮对测定方法的干扰;通过紫外分光光度法比较分析了青翘、老翘及连翘其他不同部位的总苯乙醇苷含量及总抗氧化能力。结果显示检测波长λ_(max)=330 nm时,总苯乙醇苷在6.28～25.10 mg/L范围内线性关系良好(R~2=0.999 6),平均加样回收率为98.31%(RSD=1.54%),且连翘中木脂素对测定无干扰,黄酮对测定方法有微弱干扰。青翘、老翘及连翘其他不同部位总苯乙醇苷含量为:根主干青翘新茎叶老茎花老翘。抗氧化结果表明,青翘、老翘及连翘其他不同部位的总抗氧化能力与总苯乙醇苷的含量具有较好的相关性,提示总苯乙醇苷类化合物是体现连翘具有总抗氧化能力的主要活性物质之一。该法操作简便、灵敏度高、重复性和回收率良好,可用于连翘中总苯乙醇苷的含量测定及质量控制。     

小花忍冬叶提取物的抗氧化活性

通过T-AOC法、DPPH法、Fenton法体外抗氧化试验,对小花忍冬叶乙醇提取物的各个萃取部位进行抗氧化活性研究.结果表明,小花忍冬叶5种提取物均具有不同程度的抗氧化活性,乙酸乙酯部分羟自由基清除活性最强,IC_(50)值为67.0μg/mL;清除DPPH·自由基IC_(50)为7.2μg/mL,均高于对照Vc.研究结果提示小花忍冬叶乙醇提取物乙酸乙酯萃取部分具有很强的抗氧化活性,可作为一种新型的天然抗氧化剂和自由基清除剂,具有良好的开发前景.     

贯叶连翘的化学成分及其提取方法研究进展

中药贯叶连翘因其显著的药理作用及临床应用效果受到人们越来越多的关注.介绍了贯叶连翘的主要化学成分,包括萘骈二蒽酮类化合物、间苯三酚类化合物及黄酮类化合物等;概述了其活性成分的分离纯化及HPLC检测方法的研究进展.拟为大量制备贯叶连翘活性成分以及相关药物的质量控制提供研究基础.     

西北产贯叶连翘挥发性化学成分研究

目的为了研究西北产贯叶连翘挥发性化学成分。方法采用传统水蒸汽蒸馏法提取贯叶连翘全草挥发油,并通过气相色谱/质谱/计算机联用技术测定了提取物的化学成分。结果从中鉴定出63种化合物,结果显示氧化石竹烯(6.94%)、环十二烷(3.67%)、苄醇(2.14%)、斯巴醇(3.36%)、环十四烷(1.96%)、苯并呋喃酮(1.30%)、喇叭茶醇(1.32%)等化合物为贯叶连翘挥发油的主要成分。结论西北地区的贯叶连翘挥发油成分与文献报道的其他地区产贯叶连翘挥发油成分有很大不同,说明地域和气候环境对植物的成分组成有很大影响。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

<正>~~     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

英文诗歌中的喻类修辞

为了有助于提高英文爱好者的个人情操、文化素养和学习兴趣,以及专业人员对英语学习和研究进行多途径的探索,本文通过一些精选诗歌的引证和分析,着重论述了喻类修辞法在英文诗歌中的运用其及效果。     

Man Is Unable to Change the Miserable Life——Analysis of the Arrangement of Four Characters in The Glass Menagerie

Tennessee Williams is considered as one of the most important American playwrights since World War II.The Glass Menagerie is his first successful drama,which describes a tragic situation of family and means to say that Man is unable to change the miserable life,no matter whatever means he try,This essay focuses on the analysis of the arrangement of the four main characters:Laura.Amanda,Jim and Tom to reveal the theme.Laura is fragile.Amanda is brave.Jim is vital.Tom is sensible.And all of them develop and try the different means to struggle against life,but fail tragically.With the evidence,the paper comes to conclusion naturally that Man is unable to change the miserable life,and he dooms to fail.     

Characterization of root-nodulating bacteria on Retama raetam in arid Tunisian soils

The aim of this study is to investigate the diversity of Retama raetam root-nodule bacteria isolated from arid regions of Tunisia. Twelve isolates, chosen as representative for different 16S rRNA gene patterns, were characterized by 16S rRNA gene sequencing and phenotypic analysis. Isolates were assigned to Sinorhizobium, Rhizobium and Agrobacterium. Symbiotic properties of Sinorhizobium and Rhizobium isolates showed a large diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Strain RK 22 identified as Rhizobium was the most effective isolate.     

WIMAX与WI-FI技术分析及联合组网

介绍了WiMAX与Wi-Fi两种无线宽带接入技术,并对两者之间的关系及相互之间的影响做了对比及分析,并对WiMAX的关键技术进行了详细说明,最后对两者的联合组网方式做了简单的探讨。     

An Affordable Accurate Evaluation of the Binding Conformations Predicted by Molecular Docking Studies in Bio-System

正Recently,docking has been widely used to predict the binding-modes of protein-inhibitors,when the crystal complexes structure was absent.Most docking algorithms are able to generate a large number of probable conformations,it,however,is difficult to effectively evaluate these docking poses and identify the most reasonable bindingmode.In the present study,on the basis of the crystallographic data of human 3-hydroxy-3-methylglutaryl coenzyme