一种简单、快速、微量聚丙烯酰胺凝胶等电聚焦电泳方法

Bio-Rad公司的微量聚丙烯酰胺凝胶等电聚焦电泳(ModelⅢ Mini IEF Cell),不需要使用电极缓冲液,聚焦电泳时间仅用1.5小时,效果甚佳,但要使用该公司专有的凝胶支持薄膜,难于推广应用,我们经过试验,建立了一种简单、快速的微量凝胶等电聚焦电泳方法,40min完成等电聚焦过程,采用快速染色、脱色和干燥,将电泳图谱制成透明的薄膜,整个过程可以     

我国不同地区东亚钳蝎(Buthus martensii Karsch)毒在三种类型电泳中的比较研究

用SDS—不连续聚丙烯酰胺凝胶板电泳、pH4.5—不连续聚丙烯酰胺凝胶板电泳和聚丙烯酰胺凝胶圆盘等电聚焦电泳,分离我国不同地区东亚钳蝎毒。其图谱表明:不同产地的东亚钳蝎毒蛋白的种类及含量存在一定的差异,地区相近,差异较小,反之亦然。     

rhIGF-1等电点的测定

目的：通过测定rhIGF-1等电点为例,建立一种快速测定蛋白质等电点的方法。方法：采用等电聚焦电泳（isoelectric focusing,IEF）和高效液相色谱（HPLC）连用的方法,主要以7．5％的凝胶浓度、3％的交联度及6％的两性电解质浓度配置凝胶,电泳后的凝胶经凝胶成像系统和HPLE分析确定目的条带及其pI值。结果：rhIGF-1的等电点为pI=8．20,pH梯度曲线线形回归方程为Y=0．0664X＋3．8217,相关系数r达0．9956,说明等电聚焦电泳测定结果准确。     

超薄平板微型聚丙烯酰胺凝胶的等电聚焦电泳方法--介绍一种高效、快速的生物同工酶分析方法

介绍了一种简易、高效、快速的生物同工酶分析方法——超薄平板微型聚丙烯酰胺凝胶的等电聚焦电泳方法。该方法与目前国内外市场销售的同种用途等电聚焦的产品 (如BIO- RAD公司的 model1 1 1 Mini IEF Cell)相比 ,具有以下优点 :实验操作灵活 ,用途更广 ;谱带清晰 ;每次可实验的样本量大 ;电泳所需时间短 ;实验费用低 ;适用于多种酶系统的同工酶和等位酶分析 ;凝胶干燥不需任何设备且能长期保存 ;样本用量少。     

三种分析水稻F1代幼苗生长过程中酯酶同工酶变化的电泳方法比较

利用聚酯胶片作为凝胶支持物的超薄等电聚焦电泳(UTLIEF)研究水稻F1种子萌发过程中的酯酶同工酶多态性变化的结果表明,UTLIEF相比非变性不连续聚丙烯酰胺电泳(native-PAGE)和常规等电聚焦电泳(IEF)得到的酯酶同工酶图谱更清晰,酶带数目和强弱的多态性变化更高,用pH 2～9的两性电解质时等电聚焦的电泳效果较好.     

一种简便经济的薄层凝胶电泳保存方法——滤纸转移自干法

在分析性聚丙烯酰胺凝胶电泳特别是平板等电聚焦电泳中,薄层凝胶越来越被广泛采用,它有节省试剂、加样量少、电泳时间短、分辨率高及冷却效果好等优点。分析者都希望能将电泳染色后的凝胶理想地保存下来,目前所采用的方法均是直接将凝胶干燥在玻璃板或凝胶支持膜上(由于凝胶太薄不能转移),或者使用专用的透明保存膜,有时还要用真空干燥器干燥。     

我国不同地区东亚钳蝎（Buthus martensii Karsch）毒在三种…

用ＳＤＳ－不连续聚丙烯酰胺凝胶板电泳、ｐＨ４．５－不连续聚丙烯酰胺凝胶板电泳和聚丙烯酰胺凝胶圆盘等电聚焦电泳,分离我国不同地区东亚钳蝎毒。其图谱表明：不同产地的东亚钳蝎毒蛋白的种类及含量存在一定的差异,地区相近,差异较小,反之亦然。     

醋酸纤维素膜上的蛋白质等电聚焦电泳

等电聚焦电泳一般以聚丙烯酰胺作为支撑物。但凝胶配制麻烦,两性载体用量多,价格昂贵。利用醋酸纤维素膜进行等电聚焦电泳,则可能克服上述缺点。但是醋酸纤维素膜的强电渗作用,影响了等电聚焦。过去解决这一问题的方法,条件复杂,要求高,有些试剂国内无法得到。我们试用了甲基化方法来封闭醋酸纤维素膜上的解离基团,有效地消除了电渗作用,不需转移而直接进行了大鼠血浆凝血酶原的酶联免疫染色。     

琼脂糖电内渗对电泳的影响

用电内渗不同(0、0.03、0.08、0.20mr)的琼脂糖制成凝胶或电极缓冲液凝胶条,观察对电泳行为的影响.结果表明等电聚焦电泳必须使用无电内渗琼脂糖.不同电内渗的琼脂糖制成的电极缓冲液凝胶条对SDS电泳无显著影响,但对常规聚丙烯酰胺凝胶电泳有不同程度的影响,电内渗越高,越不利于电泳的进行.     

超薄平板微型聚丙烯酰胺凝胶的等电聚焦电泳方法——介绍一种高效、快速的生物同工酶分析方法

介绍了一种简易、高效、快速的生物同工酶分析方法－－超薄平板微型聚丙烯酰胺凝胶的等电聚焦电泳 方法。该方法与目前国内外市场销售的同种用途等电聚焦产品（如ＢＩＯ－ＲＡＤ公司的ｍｏｄｅｌ１１Ｍｉｎｉ ＩＥＦ Ｃｅｌｌ）相比,具有以下优点：实验操作灵知,用途更广;谱带清晰;每次可实验的样本量大;电泳所需时间短;实验费用低;适用于多种酶系统的同工酶和等位酶分析;凝胶干燥不需任何设备且能长期保存;样本用量少。     

A collocation approach to the numerical calculation of simple gradients in reaction-diffusion systems

Reaction diffusion equations are frequently used to model pattern formation problems in biology, but numerical experiments in two or three space dimensions can be expensive in computing time. We show that the spectral method with collocation is a particularly efficient method for the numerical study of the evolution of simple patterns in such models. In many cases of interest, the scheme is sufficiently simple and efficient for calculations to be carried out on a micro-computer.     

PCR amplification of microdissected wheat chromosome arms in a simple 'single tube' reaction

A novel method for the adaptor-mediated PCR amplification of microdissected chromosome arms is described. This simple and versatile protocol eliminates the need for enzymatic micromanipulation in nanoliter volumes and permits the efficient amplification of as little as two wheat chromosome arms in a 'single tube' reaction.     

Estimating blood phenotype probabilities and their products.

We consider two methods of estimating phenotype probabilities for a number of standard genetic markers like the ABO, MNSs, and PGM markers. The first method is based on the maximum likelihood estimates of the allele probabilities, and the second (multinomial) method uses the phenotype proportions in the sample. The latter is easy to use, the estimates are always unbiased, and simple formulae for variances are available. The former method, although giving more efficient estimates, requires the assumption of panmixia so that the Hardy-Weinberg law can be used. The two methods are compared theoretically, where possible, or by simulation. Under panmixia, the maximum likelihood estimates can be substantially more efficient than the multinomial estimates. The estimates are also compared in the codominant allele case for nonpanmictic populations. The question of efficiency is of importance when estimating the probability of obtaining a given set of phenotypes, i.e., the product of individual phenotype estimators. This problem is discussed briefly.     

A measure of DNA sequence dissimilarity based on free energy of nearest-neighbor interaction

We develop a novel method of asserting the similarity between two biological sequences without the need for alignment. The proposed method uses free energy of nearest-neighbor interactions as a simple measure of dissimilarity. It is used to perform a search for similarities of a query sequence against three complex datasets. The sensitivity and selectivity are computed and evaluated and the performance of the proposed distance measure is compared. Real data analysis shows that is a very efficient, sensitive and high-selective algorithm in comparing large dataset of DNA sequences.     

Efficient ligation and cloning of DNA fragments with 2-bp overhangs

Various methods of ligation are currently available and routinely used by molecular biologists, such as blunt end ligation, cohesive end (two and four overhangs), and ligation of Taq polymerase-derived products. However, there is no efficient method for the cloning of DNA fragments with 2-bp overhangs. We present a simple method for the efficient ligation of DNA fragments with 2-bp overhanging ends, ranging in size from 0.7 to 2.5 kbp. Our method involves the initial heating and flash freezing of the vector-insert DNA mix, and a subsequent unique ligation reaction. This method provides a new molecular biology tool for researchers.     

A simple and efficient method for site-directed mutagenesis with double-stranded plasmid DNA.

A general, simple and efficient method for preparing site-specific mutations in double-stranded plasmid DNA without the need for special plasmids, bacterial strains or reagents is described. Only one synthetic oligonucleotide for each mutation is required, subcloning is unnecessary and a high efficiency of mutation (58-97%) was obtained. If two synthetic oligonucleotide primers are used, two separate mutations can be simultaneously created in a single reaction tube.     

用RAPD技术鉴定两个小冰麦易位系

本文对从小冰麦异附加系中选育出的两个抗锈品系小冰麦33号,小冰麦34号及其原始亲本新曙光一号和抗源供体天兰冰草进行了RAPD分析,确定了小冰麦33号和小冰麦34号是含一段冰草DNA的易位系,文中还讨论了RAPD做为一种准确,快速鉴定易位系的方法的可行性。     

Preparation of homogeneous human prostatic acid phosphatase using concanavalin A-sepharose 4-B.

A simple, rapid and efficient procedure is presented for the purification of human prostatic acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2) to homogeneity. The method employs two steps suitable for use with large quantities of material, followed by chromatography on concanavalin A-Sepharose as its sole column step. The procedure also permits the recovery of purified enzyme in higher yields than earlier methods.     

Semi-parametric estimation of the binormal ROC curve for a continuous diagnostic test

Not until recently has much attention been given to deriving maximum likelihood methods for estimating the intercept and slope parameters from a binormal ROC curve that assesses the accuracy of a continuous diagnostic test. We propose two new methods for estimating these parameters. The first method uses the profile likelihood and a simple algorithm to produce fully efficient estimates. The second method is based on a pseudo-maximum likelihood that can easily accommodate adjusting for covariates that could affect the accuracy of the continuous test.     

Comparison of two methods for extraction of enchytraeids

A comparison was made of two methods for the extraction of enchytraeids, the O’Connor (1957) method and the Römbke (1995) method; the latter was originally proposed as a standard method for monitoring environmental pollution. The average number of enchytraeids extracted by the Römbke method was significantly greater. This simple and convenient method was shown to be as efficient as the traditional method when applied in both laboratory and field studies.