用线粒体Cytb基因序列探讨冬虫夏草寄主蝠蛾的系统进化关系

为探讨冬虫夏草寄主蝠蛾种属间的系统进化关系,采用CTAB法分别从18个冬虫夏草居群的虫草虫体头部和2种寄主蝠蛾中提取基因组DNA,PCR扩增获得冬虫夏草寄主线粒体Cytb基因片段序列.结合GenBank中的蝙蝠蛾科24种冬虫夏草寄主的同源序列,构建NJ系统树.结果表明,双栉蝠蛾属(Bipectilus)先于蝠蛾属(Hepialus)和类蝠蛾属(Hepialiscus)分化;蝠蛾属的冬虫夏草寄主种类众多形态各异,且均有特定的地理分布,蝠蛾属的种间遗传分化也较明显,蝠蛾属可能是多系起源;Cytb基因序列在冬虫夏草寄主蝠蛾种属间存在较丰富的变异,在蝠蛾属中除草地蝠蛾和金沙蝠蛾的该段序列完全一致外,其他种类蝠蛾种间变异率为0.23%—9.24%,Cytb基因序列可用于冬虫夏草寄主昆虫种的鉴定,但有必要获取更多种类的寄主昆虫来进一步验证.通过对冬虫夏草虫体头部提取的DNA进行PCR扩增获得其寄主蝠蛾Cytb基因序列的方法准确有效,有助于进一步获取更多的基因序列对更多的冬虫夏草居群和寄主种类进行系统发育、居群遗传结构及菌虫相互关系等研究.     

青海拉脊蝠蛾幼虫分类特征研究

首次报道了冬虫夏草的寄主之一 ,拉脊蝠蛾HepialuslagiiYan幼虫头、胸、腹各部分的形态特征 ,其颜色、毛色、毛序及各龄幼虫的头宽和体长 ,可作为鉴别种类依据。     

野外放归大熊猫和圈养大熊猫肠道正常菌群的研究

对四川卧龙中国保护大熊猫研究中心1只放归亚成体大熊猫和3只圈养亚成体大熊猫肠道正常菌群的种类、数量和分布情况进行了比较研究，结果鉴定出17种细菌，发现放归大熊猫和圈养大熊猫肠道优势菌群均为肠杆菌、肠球菌和乳杆菌，与圈养大熊猫相比，大熊猫放归野外后，肠道菌群中的肠球菌增多，肠杆菌和乳杆菌的数量有所下降，芽孢杆菌和酵母菌的检出率增大。     

仁扇舟蛾幼虫肠道可培养细菌群落结构分析

【目的】了解仁扇舟蛾(Clostera restitura)肠道共生细菌的主要类群及其群落结构特征,明确仁扇舟蛾幼虫前、中和后肠可培养细菌的种类及群落结构组成,为进一步研究特异功能细菌的生理生化特征和功能提供基础。【方法】选取仁扇舟蛾5龄幼虫进行肠道解剖,分离前、中和后肠不同肠段,研磨稀释10^-1~10^-6,分别涂布于NA和LB固体培养基上,每个处理重复3次,28 ℃培养72 h。后对前、中和后肠可培养细菌进行分离纯化培养,提取细菌基因组DNA,利用 16S rDNA 基因序列分析和PCR扩增技术,获得细菌基因组序列,后与NCBI GenBank数据库进行Blast同源性比对,参考序列相似度98%以上近缘序列的物种信息,结合菌落形态特征和生理生化特性鉴定细菌种类,利用MEGA 7.0软件,采用邻接法(Neighbor-Joining)构建系统进化树。【结果】从仁扇舟蛾5龄幼虫的前、中和后肠中共分离获得22株可培养细菌,分属于变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)和放线菌门(Actinobacteria),共13个属,22个种。其中:假单胞菌属(Pseudomonas)4株,罗尔斯通菌属(Ralstonia)3株,芽孢杆菌属(Bacillus)3株,嗜麦芽寡养单胞菌属(Stenotrophomonas)2株,气球菌属(Aerococcus)2株,其余微小杆菌属(Exiguobacterium)、微球菌属(Micrococcus)、短小杆菌属(Curtobacterium)、伯克氏菌属(Burkholderia)、类芽孢杆菌属(Paenibacillus)、节杆菌属(Arthrobacter)、短状杆菌属(Brachybacterium)和两面神菌属(Janibacter)各1株。细菌的种类存在差异,前、中和后肠不同肠段的细菌种类分别为5、10和7种。3个肠段共有的细菌种类是皮氏罗尔斯菌(Ralstonia pickettii)和斯氏假单胞菌(Pseudomonas stutzeri)。【结论】仁扇舟蛾5龄幼虫肠道的可培养细菌种类较为丰富,其中以变形菌门和厚壁菌门为优势菌群。不同肠段中可培养细菌的多样性和群落结构存在差异,其中以中肠可培养细菌种类较为丰富。此次从仁扇舟蛾肠道中分离到与单宁降解相关的细菌,分析表明仁扇舟蛾肠道菌群与宿主的取食习性有关,肠道细菌可能在克服植物次生代谢物质的化学防御上发挥作用。     

普通环境长爪沙鼠肠道菌群的分离鉴定

目的调查普通环境长爪沙鼠肠道菌携带情况,为制定长爪沙鼠微生物学等级标准提供依据。方法对普通饲养环境的65只长爪沙鼠进行解剖,取回盲部内容物接种于6种不同培养基,分离菌株后同时进行生化分析和PCR测序鉴定,以期准确判断分离菌株所属菌属,并分别计算检出率。结果用6种培养基组合进行肠道菌群的分离大大提高了细菌的检出率。本研究共检出37种细菌,不同细菌感染率相差很大,阳性率在1/65（1.5%）到60/65（92.3%）之间,其中部分细菌为大鼠和小鼠致病菌。结论本研究为长爪沙鼠的微生物学等级标准的制定提供了参考数据。     

工业化生产的冬虫夏草及其制品

冬虫夏草也叫虫草、假虫草。它是一种寄生在身体很像蚕儿(蝙蝠蛾)的鳞翅目幼虫体上的子囊菌。该菌在幼虫生长的早期侵入体内蔓延,以至最后夺去幼虫生命。冬季,土内只有死亡的幼虫,直到次年夏季气候温暖潮湿时,它才由幼虫的头部长出子实体,露出土面,状似野草。长出土面的棒状子实体内生有像植物种子的子囊孢子,条件适宜它就又会寄生虫体成为冬虫夏草。     

戊糖片球菌改善高脂饮食小鼠肠道菌群机制研究

为了探究具有降胆固醇能力的肠道微生物对高脂饮食引起的高胆固醇血症的作用,本研究从人体粪便中分离出具有高效降胆固醇能力且耐胃蛋白酶、胰蛋白酶、胆盐的肠道微生物．选取优势肠道微生物进行菌种鉴定后进行小鼠实验,测定小鼠的体质量、脏器系数、肝脏及粪便的胆固醇含量,研究其降胆固醇作用．实验筛选获得具有较强降胆固醇能力的肠道微生物P4,经鉴定为戊糖片球菌(Pediococcuspentosaceus),其能够抑制高脂饮食诱导的小鼠血清中胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)的升高,降低肝脏和粪便中的胆固醇及血清中的高密度脂蛋白胆固醇(HDL-C),从而达到降血脂的目的．通过高通量测序实验分析了小鼠肠道的菌群组成,发现戊糖片球菌P4能够通过改善肠道微生物的组成和丰度降低小鼠肠道中厚壁菌门(Firmicutes)与拟杆菌门(Bacteroidetes)的比值,改善由小鼠高脂饮食引起的高胆固醇血症．因此,筛选出的戊糖片球菌P4对降胆固醇功能产品的研究开发具有重要意义.     

乌龟肠道微生物区系和排泄物抗菌研究

探讨乌龟排泄物对鱼病病原菌的抑制作用.对乌龟前肠、中肠、后肠和尿囊中微生物进行了分离和纯化,鉴定出乌龟肠道微生物区系优势菌群有肠杆菌属、埃希氏菌属、极毛杆菌属等菌属;厌氧菌有革兰氏阴性球菌、杆菌、消化链球菌,革兰氏阳性球菌、杆菌等.嗜水产气单胞菌、白色链珠菌表现对乌龟排泄物上清液最为敏感;灭菌后的乌龟排泄物上清液对供试菌均无抑制作用.     

实验室条件下西藏冬虫夏草幼虫生理机制变化研究

为研究实验室条件下西藏冬虫夏草幼虫对温度、湿度、病害等条件的生理反应以及西藏冬虫夏草幼虫的食性情况,文章对西藏冬虫夏草幼虫的外部形态及其对温度和湿度的反应及食性等方面进行观察,并绘制出西藏冬虫夏草幼虫生长曲线。结果表明：①实验室中培养西藏冬虫夏草幼虫的最佳温度范围为12℃-14℃;②西藏冬虫夏草幼虫最喜啃食红萝卜,其次为土豆和莴笋;③西藏冬虫夏草幼虫对温度具有很高的敏感性,当温度达到20℃时,幼虫完全失去活动的能力,并且此时幼虫身体表面容易感染病菌。     

耕作土壤中蚯蚓肠道可培养放线菌的多样性研究

从同一地区耕作土和森林土的蚯蚓肠道内分离得到15株和8株放线菌,分别进行形态、培养特征、16S rDNA序列鉴定和系统发育分析.对比2种土壤的理化性质和肠道放线菌的多样性发现,土壤N、P、K富集化导致放线菌数量的增加,重金属含量增高则使放线菌多样性降低.2种环境下,链霉菌属始终是肠道放线菌中的优势菌群.     

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.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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