分子生物学技术在细菌分类鉴定中的研究进展

介绍了细菌鉴定中的常用的几种分子生物学方法,即基因序列同源性分析,PCR指纹图分析,核酸杂交和DNA的G+C含量测定法,对这几种方法的原理、优点及适用领域等进行了比较和整理,提出将建立起更加完善的分子生物学技术,并随着分类技术和理论观念的发展会建立越来越多的细菌分子生物学鉴定方法及细菌分类体系。     

分子生物学方法在土壤真菌多样性研究中的应用

真菌是生态系统的重要组成成分,研究土壤中真菌的多样性和群落结构对于开发利用微生物资源、进行土壤生物修复具有重要意义。现代分子生物学的发展为研究土壤真菌提供了行之有效的方法。主要综述了限制性片段长度多态性、末端限制性片段长度多态性、变性梯度凝胶电泳、随机引物扩增多态性DNA、18S rDNA文库构建等技术的原理及在土壤真菌多样性研究中的应用。     

青霉分类方法的研究进展

介绍了青霉的传统分类方法，综述了随机扩增多态性（RAPD）、限制性片断长度多态性（RFLP）、扩增片断长度多态性（AFLP）和rDNA／rRNA序列分析等几种分子标记技术的基本原理、方法及其青霉分类鉴定中的研究进展。     

DNA芯片制作的常用方法

DNA芯片是分子生物学研究领域的重要工具。目前最常用的制作方法是将探针固定于载体上。介绍载玻片的氨基硅烷化修饰和探针的五种修饰方法 ,以及两者之间的结合方式。这些方法简单、实用、经济 ,适合国内实验室开展 DNA芯片研究工作     

核酸单链构象多态性技术研究进展

摘要单链构象多态性(SSCP)技术能分析核酸的单碱基突变,是出现最早、应用较广、备受关注的等位基因分型方法,在待检测基因的PCR制备和电泳分离奈件优化方面的应用受到了重视,而与毛细管电泳相结合,使该技术具有高通量并行化处理的特点。综述了单核苷酸构象多态性分析技术及其研究进展,介绍了SSCP技术的原理、PCR产物的制备和DNA样品变性处理,重点介绍了电泳的各种操作条件和检测系统。     

微生物降解纤维素机制的分子生物学研究进展

对纤维素酶的分子生物学，主要是该酶对天然纤维性底物的降解机制研究进展作了简要评述，包括纤维素酶的一、二、三级结构、酶分子的多形性、纤维素酶族、酶基因克隆方法及表达和分泌中存在的问题、新酶分子的构建等。并介绍对细胞融合、单克隆抗体、DNA体外定位诱变、活性中心测定和糖基化方法等在纤维素酶降解研究中的应用。     

DNA水平电泳检测重庆地区汉族人MDR1C3435T基因多态性

目的应用DNA水平聚丙烯酰胺凝胶电泳(PAGE)检测重庆地区汉族人MDR1C3435T基因的多态性。方法PCR扩增重庆地区正常汉族人外周血MDR1C3435T基因,以MboⅠ进行限制性酶切,用DNA水平PAGE作图谱分析。结果200名重庆地区汉族人MDR1C3435T基因中,表型T/T的频率为0.15,T/C为0.49,C/C为0.36。MDR1C3435T基因T频率为0.395,基因C为0.605。结论重庆地区汉族人MDR1C3435T基因的分布与我国其他地区人群基本接近,地区差异不明显。DNA水平PAGE为一种简单可靠的基因多态性分析方法,值得在基层单位推广。     

科研单位化学试剂危险品的管理

化学试剂广泛应用于医疗卫生、环境保护、生物技术、生命科学、检验检疫、国防军工、食品餐饮、化工轻工等社会诸多领域.其种类繁多,分类方法也很多,按传统分类分为通用试剂、无机试剂、有机试剂、生化试剂等,按其纯度分为优级纯(GR)、分析纯(AR)、化学纯(CP)和实验试剂(LR)、标准物质(RM)、高纯物质(SP)、指示剂(IND)、色谱试剂(HPLC)、基准试剂(PT)等.按适用领域分:生化试剂、临床诊断试剂、分子生物学试剂、食品添加剂、水分子测试试剂等.     

介绍一种简便的DNA胶回收方法

目前DNA的回收方法主要有柱回收法、玻璃奶回收法等，这些方法回收效率较低，难以保证DNA的回收率及纯度。我们介绍一种简单经济适用，而且回收率较高的方法，并与传统的回收方法进行了比较。     

黄芪干燥根与鲜品总DNA提取方法评价

以采挖的2份新鲜黄芪根为原料,经干燥处理另制成2份干燥根样品。利用传统SDS法和改良CTAB法对干品和鲜品黄芪总DNA提取,为黄芪中药材资源的分子生物学试验提供基础原料。结果显示:改良的CTAB法提取的干品和鲜品总DNA的A260/A280比值在正常范围值内,而SDS法提取的4个样品比值均低于1.6。对8个样品总DNA进行琼脂糖电泳显示,CTAB法提取的样品条带清晰无拖尾现象,鲜品提取的总DNA浓度和质量高于干品。     

New PCR Assays for the Identification of Fusarium verticillioides, Fusarium subglutinans, and Other Species of the Gibberella fujikuroi Complex

Fusarium verticillioides and Fusarium subglutinans are important fungal pathogens of maize and other cereals worldwide. In this study, we developed PCR-based protocols for the identification of these pathogens targeting the gaoB gene, which codes for galactose oxidase. The designed primers recognized isolates of F. verticillioides and F. subglutinans that were obtained from maize seeds from several producing regions of Brazil but did not recognize other Fusarium spp. or other fungal genera that were either obtained from fungal collections or isolated from maize seeds. A multiplex PCR protocol was established to simultaneously detect the genomic DNA from F. verticillioides and F. subglutinans. This protocol could detect the DNA from these fungi growing in artificially or naturally infected maize seeds. Another multiplex reaction with a pair of primers developed in this work combined with a pre-existing pair of primers has allowed identifying F. subglutinans, F. konzum, and F. thapsinum. In addition, the identification of F. nygamai was also possible using a combination of two PCR reactions described in this work, and another described in the literature.     

Development of solution-gated graphene transistor model for biosensors

The distinctive properties of graphene, characterized by its high carrier mobility and biocompatibility, have stimulated extreme scientific interest as a promising nanomaterial for future nanoelectronic applications. In particular, graphene-based transistors have been developed rapidly and are considered as an option for DNA sensing applications. Recent findings in the field of DNA biosensors have led to a renewed interest in the identification of genetic risk factors associated with complex human diseases for diagnosis of cancers or hereditary diseases. In this paper, an analytical model of graphene-based solution gated field effect transistors (SGFET) is proposed to constitute an important step towards development of DNA biosensors with high sensitivity and selectivity. Inspired by this fact, a novel strategy for a DNA sensor model with capability of single-nucleotide polymorphism detection is proposed and extensively explained. First of all, graphene-based DNA sensor model is optimized using particle swarm optimization algorithm. Based on the sensing mechanism of DNA sensors, detective parameters (I_ds and V_gmin) are suggested to facilitate the decision making process. Finally, the behaviour of graphene-based SGFET is predicted in the presence of single-nucleotide polymorphism with an accuracy of more than 98% which guarantees the reliability of the optimized model for any application of the graphene-based DNA sensor. It is expected to achieve the rapid, quick and economical detection of DNA hybridization which could speed up the realization of the next generation of the homecare sensor system.     

Development of a ligation-based impedimetric DNA sensor for single-nucleotide polymorphism associated with metabolic syndrome

Single-nucleotide polymorphism (SNP) detection is becoming important in molecular diagnostics, clinical assay, and novel drug development. Electrochemical methods are well suited for the DNA diagnostics system. Since electrochemical reactions directly emit an electronic signal, expensive signal transduction equipment is not required. We describe the development of a novel DNA sensor that utilizes impedance spectroscopy and DNA ligation reaction on a gold electrode. Impedance spectroscopy enables label-free detection and is nondestructive and useful in equivalent circuit models for interpretation on an electrode surface, whereas from the ligation reaction, the specificity is derived by the allele-specific oligonucleotide of the capture probe on immobilized gold electrode. In other words, DNA diagnostics system using the combination of impedance spectroscopy and ligation reaction is simple, rapid, and allele specific. In this report, we have described a ligation-based impedimetric DNA sensor and the analysis of Trp64Arg polymorphism in the beta3-adrenergic receptor gene (ADRβ3).     

高循环利用的无卤阻燃聚对苯二甲酸丁二醇酯(PBT)研制

综合对比自行研制的无卤阻燃PBT与传统卤系阻燃PBT的力学性能、阻燃性能、电性能.研究无卤阻燃PBT材料在多次循环回收利用情况下的性能变化.结果表明:在满足相同的阻燃要求时,无卤阻燃PBT和卤系阻燃.PBT的综合力学性能相当;无卤阻燃PBT的电性能明显优于卤系阻燃PBT;无卤阻燃PBT可在大比例回填下综合性能基本保持不变.     

Identification of single microbial particles using electro-dynamic balance assisted laser-induced breakdown and fluorescence spectroscopy

Online characterization of fungal and bacterial spores is important in various applications due to their health and climatic relevance. The aim of this study was to demonstrate the capability of the combination of electro-dynamic balance assisted laser-induced breakdown spectroscopy (LIBS) and laser-induced fluorescence (LIF) techniques for the online detection of single fungal spores (Aspergillus versicolor and Penicillium brevicompactum) and bacteria (Bacillus aureus). The method enabled sensitive and repeatable LIBS analysis of common elemental components (Ca, Na, and K) from single microbial particles for the first time. Significant differences in the concentrations of these elements were observed between the species, e.g., bacterial spores had over three orders of magnitude higher Ca concentration (2 × 10^?12 g/particle) compared to fungal spores (3–5 × 10^?16 g/particle). The LIF analysis has previously been used to distinguish bioaerosols from other aerosols due to their fluorescence ability. This study showed that combination of LIF and LIBS analysis is a promising tool for identification of different bioaerosol particle types.

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