鱼类感染嗜水气单胞菌后的病理特征及其防控措施

嗜水气单胞菌为水产养殖中一种常见的致病菌,能引发养殖鱼类暴发细菌性败血症而造成大量死亡,给水产行业带来巨大的经济损失。结合国内外的研究进展,阐述了鱼类在感染嗜水气单胞菌后的病理特征、内部组织损伤及在水产养殖中对嗜水气单胞菌的防控措施,以期为鱼类的健康生态养殖提供指导。     

中华鳖抗嗜水气单胞菌亚单位疫苗的制备与应用

水体条件致病菌嗜水气单胞菌对中华鳖养殖业的危害巨大.为预防嗜水气单胞菌的感染,提高中华鳖免疫抵抗力,研究开发嗜水气单胞菌疫苗是一种有效的方法.利用PCR手段克隆获得嗜水气单胞菌DnaK和DnaJ两个基因,并将两基因重组到大肠杆菌表达载体上,转化至大肠杆菌表达菌株,纯化获得了重组蛋白rDnaKAh和rDnaJAh.将两个重组蛋白分别与弗氏佐剂充分混合制备成疫苗,腹腔注射中华鳖幼鳖,加强免疫一次后,用已分离获得的致病菌株感染中华鳖幼鳖,实验结果表明rDnaK具有81.8％的免疫保护效应,而rDnaJ仅具有31.8％的免疫保护效应.     

广西斑点叉尾鮰源嗜水气单胞菌灭活疫苗的制备

本研究针对广西地区分离到的致病性嗜水气单胞菌,开发区域定制化的灭活疫苗,以实现鱼病的有效预防和控制。首先,对斑点叉尾鮰源嗜水气单胞菌在LB培养基中的生长曲线,培养基的最适pH值,以及培养基中添加蔗糖对嗜水气单胞菌生长影响进行研究;随后探索嗜水气单胞菌灭活疫苗的制备方法,并在细胞水平和斑点叉尾鮰活体水平上研究疫苗的安全性,开展疫苗对斑点叉尾鮰的免疫保护实验。结果表明嗜水气单胞菌浓度与菌液OD值间具有较好的线性关系,其回归方程为y=2E-10x+0.1399,R2=0.975 4。用于培养嗜水气单胞菌的LB培养基最适pH值为7.0～7.5,且在培养基中添加蔗糖能显著促进嗜水气单胞菌的生长。研究制备的嗜水气单胞菌灭活疫苗在细胞水平和鱼活体水平均安全无毒,且对斑点叉尾鮰的免疫保护率可达到75%。据此,本研究初步建立起广西斑点叉尾鮰源嗜水气单胞菌灭活疫苗的制备工艺。     

日本鳗鲡嗜水气单胞菌的分离鉴定与免疫相关基因变化的研究

2018年1—2月,饲养于集美大学疫苗中心的日本鳗鲡(Anguilla japonica)出现了一定数量的死亡,从病鱼脾脏中分离到一株优势菌株,结合Biolog系统微生物鉴定和分离菌16S rRNA基因的测序结果,显示该分离菌为嗜水气单胞菌(Aeromonas hydrophila)。采集自然感染嗜水气单胞菌前后的日本鳗鲡肝、脾、肾和粘液为cDNA模板,采用荧光定量PCR(real-time PCR)法检测组织中Toll样受体3(tlr3)、肿瘤坏死因子(tnf-α)、C型溶菌酶(lysC)和环氧合酶(cox2)等免疫相关基因的表达变化。结果表明:日本鳗鲡自然感染嗜水气单胞菌后,tlr3、tnf-α、cox2均未发现显著性的变化,但lysC的含量在日本鳗鲡脾脏和肾脏中均出现显著性上调,即,自然感染嗜水气单胞菌的日本鳗鲡的抗感染免疫功能与C型溶菌酶密切相关。     

运用SELEX技术筛选嗜水气单胞菌适配子

以嗜水气单胞菌为研究对象,采用适体筛选技术(SELEX,system evolution of ligands by expo-nential enrichment),利用体外合成的长度为78个核苷酸的随机ssDNA文库,以嗜水气单胞菌为靶目标进行12轮的筛选,利用生物素-抗地高辛碱性磷酸酶显色系统检测DNA适配子与嗜水气单胞菌的亲和力.研究结果表明:随着筛选轮数的增加,DNA适配子与嗜水气单胞菌结合后显色,A(absorbance)值逐渐增加,亲和力由最初的0.32升到第9轮的0.72.研究已初步筛选到与嗜水气单胞菌具有高亲和力的DNA适配子,为嗜水气单胞菌的二级结构研究及其检测试剂盒的研发提供了基础.     

双重PCR法快速检测欧鳗鲡嗜水气单胞菌

采用已知的嗜水气单胞菌编码溶血素(Hemolysin)和外膜蛋白(Ompts)的基因序列为目的基因,依据其保守序列设计两对相应引物,用双重PCR方法检测了32株从发病欧鳗鲡分离的细菌,将检测结果与试剂盒快速生化鉴定结果进行比较.以嗜水气单胞菌为阳性对照,以大肠杆菌、枯草芽胞杆菌、铜绿假单胞菌、鳗弧菌、溶壁微球菌、金黄色葡萄球菌为阴性对照检测了嗜水气单胞菌溶血素与外膜蛋白基因的特异性.结果表明:被检测的32株欧鳗鲡致病菌中,检测到的4株既有溶血素基因又有外膜蛋白基因的细菌,其生化鉴定结果全部为嗜水气单胞菌,而仅具有外膜蛋白基因的13株细菌中只有5株生化鉴定结果为嗜水气单胞菌.证明双重PCR法可用于快速检测部分嗜水气单胞菌.     

卵黄抗体在防治中华鳖气单胞菌病中的应用

探讨了卵黄特异性抗体在防治中华鳖气单胞菌病中的应用 .产蛋鸡经嗜水气单胞菌免疫后 ,产生了高效价的卵黄抗体 ;冻干过程中抗体活性基本没有损失 ;体外抑菌试验表明 ,该特异性抗体具有较强抑制嗜水气单胞菌的效果 ;鳖场被动免疫防治试验证明 ,该抗嗜水气单胞菌卵黄抗体对中华鳖气单胞菌病具有良好的防治效果 .     

嗜水气单胞菌的研究进展

回顾了嗜水气单胞菌的生物学性状、血清型、致病性以及致病机理的研究情况,并概述了嗜水气单胞菌的致病毒力因子和诊断检测技术方面的研究情况及新的研究进展.     

罗非鱼肠炎病病原体的分离与鉴定

从患病罗非鱼的血液、肝脏、脾脏中分离到细菌，经理化鉴定，该菌为嗜水气单胞菌，动物回归试验阳性，认定该罗非鱼的肠炎病是由嗜水气单胞菌引起。     

嗜水气单胞菌毒力与毒力基因分布的相关性

采用PCR扩增的方法对9株鱼源嗜水气单胞菌AEROM ONAS HYDROPHILA中的气溶素基因(AERA)、溶血素基因(HLYA)和丝氨酸蛋白酶基因(AHPA)进行了扩增。结果表明,6/9的A.HYDROPHILA中存在AERA基因,8/9的A.HYDROPHILA中存在HLYA基因,而在7/9的A.HYDROPHILA中检测到AHPA基因。通过比较基因检测的结果与嗜水气单胞菌对鲫鱼的致病性,发现AHPA阴性菌株是无毒株,强毒株都呈AERA HLYA AHPA 基因型。AERA HLYA AHPA 基因型是致病性嗜水气单胞菌主要的基因型。本研究首次发现AHPA阳性的嗜水气单胞菌皆为毒力菌株,并且发现AERA和AHPA基因存在相关性,探讨了嗜水气单胞菌致病性与毒力基因分布的关系。     

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.     

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     

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