全部

(一) 原理 蛋白质在水溶液中的溶解度是由蛋白质周围亲水基团与水形成水化膜的程度以及蛋白质分子带有电荷的情况决定的。当用中性盐加入蛋白质溶液中性盐对水分子的亲和力大于蛋白质于是蛋白质分子周围的水化膜层减弱乃至消失。同时中性盐加入蛋白质溶液后由于离子强度发生改变蛋白质表面电荷大量被中和更加导致蛋白溶解度降低使蛋白质分子之间聚集而沉淀。 (二) 主要材料 ...

随着分子生物学的发展，越来越多的科研人员熟练掌握了分子生物学的各种试验技术，并研制成套试剂盒，使基因克隆表达变得越来越容易lIl。但分子生物学的上游工作往往并非是最终目的，分子克隆与表达的关键是要拿到纯的表达产物，以研究其生物学作用，或者大量生产出可用于疾病治疗的生物制品。相对与上游工作来说，分子克隆的下游工作显得更难，蛋白纯化工作非常复杂，除了要保证纯度外，蛋白产品还必须保持其生物学活性。纯化工 ...

获得蛋白质的晶体结构的第一个瓶颈，就是制备大量纯化的蛋白质（>10mg），其浓度通常在10mg/ml 以上，并以此为基础进行结晶条件的筛选。运用重组基因的技术，将特定基因以选殖（clone）的方式嵌入表现载（expressionvector）内，此一载体通常具有易于调控的特性。之后再将带有特定基因的载体送入可快速生长的菌体中，如大肠杆菌（Escherichia coli），在菌体快速生长的同 ...

电泳切胶注意事项: 1.电泳的buffer和gel都是新制的，切胶的台子清理干净，刀片最好洗净灭菌，总之一句话就是保证切下的带没有外源dna污染。 2.切胶是要把整个目的片断所在位置的胶全部回收。为了减少胶的体积，可以用相对比较薄的胶来做，只要够点样即可，也可采用薄而宽的梳子来跑胶。 3.关于防护，在一般有机玻璃后就足够了，戴上防护面具以保护眼睛，如果你戴树脂眼镜就可以了。要是非常害怕紫外照射 ...

ACDP Advisory Committee on Dangerous Pathogens BSA Bovine Serum albumin BSE Bovine spongiform encephalopathy BVDV Bovine viral diarrhoea virus FBS Fetal bovine serum EC European Community ECACC ...

1.Basic Techniques - The “Do’s and Don'ts” of Cell Culture Given below are a few of the essential "do’s and don’ts" of cell culture. Some of these are mandatory ...

1.Cell Culture Scale-up Systems Most tissue culture is performed on a small scale where relatively small numbers of cells are required for experiments. At this scale cells are usually grown in T flask ...

1.Authentication Techniques Whatever the scope of work to be carried out it is important to know that the work is being conducted using the correct reagents. This is no less important for cell culture ...

Introduction Quality is important in all aspects of tissue culture since the quality of materials used i.e. media and other reagents) will affect the quality of the cultures and products derived from ...

It is bad practice to maintain a cell line in continuous or extended culture for the following reasons:~undefined Risk of microbial contamination ~undefinedLoss of characteristics of interest (i.e. surface antigen or ...

1.Cryopreservation of Cell Lines The aim of cryopreservation is to enable stocks of cells to be stored to prevent the need to have all cell lines in culture at all times. It is invaluable when dealing ...

In general terms cultured cells require a sterile environment and a supply of nutrients for growth. In addition the culture environment should be stable in terms of pH and temperature. Over the last t ...

1.Primary Cultures Primary cultures are derived directly from excised normal animal tissue and cultured either as an explant culture or following dissociation into a single cell suspension by enzyme d ...

Purifying Large E. coli Restriction Fragments from Pulsed-Field Gels DNA Preparation E. coli chromosomal DNA is prepared following the method of Heath et al. ( J. Bacteriol. 174 1992). Cells ...

Large numbers of cell lines look identical. Cell lines with very different origins and biological characteristics typically cannot be separated on grounds of morphology or culture characteristics. Inf ...

1.Risk Assessment The main aim of risk assessment is to prevent injury protect property and avoid harm to individuals and the environment. The performance of risk assessment is a legal requirement und ...

各种细菌具有各自独特的酶系统，因而对底物的分解能力不同，其代谢产物也不同。用生物化学方法测定这些代谢产物，可用来区别和鉴定细菌的种类。利用生物化学方法来鉴别不同细菌，称为细菌的生物化学试验或称生化反应。生物化学试验的方法很多，这里主要介绍碳水化合物的代谢试验 1．糖（醇、苷）类发酵试验 （1）原理：不同种类细菌含有发酵不同糖（醇、苷）类的酶，因而对各种糖（醇、苷）类的代谢能力也有所不同，即使能分解 ...

1.Laboratory Design Perhaps one of the most under-rated aspects of tissue culture is the need to design the facility to ensure that good quality material is produced in a safe and efficient manner. Mo ...

ECACC and Human Genetic Research The European Collection of Cell Cultures (ECACC) was first established within CAMR Salisbury UK in 1984 and has grown to be one of the largest animal cell culture coll ...

细胞培养基本概念 细胞培养是指从体内组织取出细胞在体外模拟体内环境下，使其生长繁殖，并维持其结构和功能的一种培养技术。细胞培养的培养物可以是单个细胞，也可以是细胞群。 细胞培养目的与用途 1、科学研究：药物研究开发与基础研究 药物研究与开发 (1) 新药筛选：如化学合成药物药效研究、中药有效成分筛选与鉴定等。 (2) 疫苗研究与开发：如病毒性疫苗的研究与开发（肝炎病毒疫苗、艾滋病疫苗等）、肿瘤疫苗 ...