共查询到20条相似文献,搜索用时 15 毫秒
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G. Derflinger 《Biometrical journal. Biometrische Zeitschrift》1979,21(1):25-38
A general algorithm for the factor analysis is developed, which contains the alpha factor analysis, the maximum likelihood method and the minres method as special cases. This algorithm, which is a multidimensional NEWTON algorithm, uses the partial derivatives of the reproduced communalities with respect to the inserted ones. The partial derivatives are got by means of the perturbation theory. 相似文献
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Yuji Nagano Hirotoshi Samejima Shukuo Kinoshita 《Bioscience, biotechnology, and biochemistry》2013,77(4):359-363
A general assay method for nucleotide pyrophosphorylases has been investigated. The principle of the method is based on the measurement of consumption rate of 5-phosphoribosylpyrophosphate (PRPP) during the enzyme reaction. In the method, an enzyme preparation for sample was incubated in a reaction mixture containing a purine or pyrimidine base and PRPP for a certain time, and the amounts of PRPP before and after the reaction were determined. The amount of PRPP was determined by an enzymatic method using orotidine-5′-monophosphate (5′-OMP) pyrophosphorylase and 5′-OMP decarboxylase. Nucleotide pyrophosphorylase activity corresponding to each purine or pyrimidine base was determined from the amount of PRPP consumed per unit time.The present method is generally applicable for determining activities of any kind of nucleotide pyrophosphorylases, and does not need any tedious separation procedure in all cases. Therefore, comparing with the conventional assay methods for nucleotide pyrophosphorylase activities, this method can be said to be much simpler and reliable. As an application of the present method, activities of several nucleotide pyrophosphorylases in Micrococcus glutamicus have been determined. 相似文献
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Jaroslav Flegr 《Preparative biochemistry & biotechnology》2013,43(4):423-433
A rapid and simple method for the isolation and purification of dsRNA is presented. The crucial step of this method is the extraction of proteins and DNA with acid phenol. After the extraction, only RNA is left in the aquaeous phase. ssRNA contamination of the RNA preparation can be greatly reduced when ammonium sulfate is present during the extraction. 相似文献
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用FTA采样卡和普通定性滤纸采集藏绵羊血样,采用NaOH法提取血液基因组DNA,利用设计的一对引物对DRB1基因第三外显子进行扩增,通过PCR产物琼脂糖凝胶检测,对普通定性滤纸与FTA采样卡的两种提取DNA的方法进行比较,结果认为采用普通定性滤纸-NaOH法提取血液基因组DNA,NaOH的最佳洗涤浓度是25 mmol/L,采用FTA-NaOH法提取血液基因组DNA,NaOH的最佳洗涤浓度是20 mmol/L,但普通定性滤纸法提取血液基因组DNA平均成本远低于FTA采样卡,普通定性滤纸法提取血液基因组DNA具有快速、便捷、经济及高效的特点. 相似文献
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建立了一种简单处理单个卵子和早期胚胎制备DNA模板的方法——KOH/DTT-Triton X裂解法,并与TE-蛋白酶K法比较了PCR扩增效率。结果,采用KOH/DTT-Triton X裂解法处理单个卵子或2-细胞胚、8-细胞胚、桑椹胚、囊胚后,作为DNA模板直接进行PCR扩增线粒体DNA片段,3对引物的PCR扩增总成功率为100%(70/70),而TE-蛋白酶K法处理的单个卵子的PCR扩增总成功率为92.9%(65/70),二者差异显著(P<0.05)。但两种方法所制备模板的PCR假阳性率均为0。实验设计的KOH/DTT-Triton X裂解法是一种有效的单个早期胚胎的DNA模板制备方法,经一次PCR扩增即能获得清晰的目的DNA条带,能够满足早期胚胎遗传物质检测的需要。 相似文献
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M. I. Drobotenko S. S. Dzhimak A. A. Svidlov A. A. Basov O. M. Lyasota M. G. Baryshev 《Biophysics》2018,63(2):177-182
In this paper, we consider a mathematical model that draws an analogy between a DNA molecule and a mechanical system consisting of two chains of interconnected pendulums. This model is designed to explore the dynamics of the system determined by rotational movements of nucleobases around a double-stranded pentose phosphate backbone. The workability of this model is assessed with respect to various factors: inhomogeneity of the chain of nucleobases, the properties of bonds in complementary pairs, and the formation of open states. It has been shown that simplified models for averaging the characteristics of the chain of nucleobases or simplification of the type of hydrogen bond in their complementary pairs influence the type of solution significantly, impairing the validity of the results. Therefore, the approach to the solution of rotational DNA molecule dynamics developed here is more consistent with its actual biomechanics. It is shown that the emergence of open states within nucleobase pairs and restoration of the closed structure may occur in the tested mathematical model. 相似文献
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一种新的DNA芯片的封闭方法 总被引:4,自引:0,他引:4
提出了一种新的DNA芯片的封闭方法:1-碘丙烷封闭方法,并对1-碘丙烷和琥珀酸酐两种不同的封闭方法的封闭效果进行了比较实验,研究封闭试剂、封闭时间对氨基DNA芯片杂交结果所产生的影响。结果表明:1-碘丙烷封闭效果明显好于琥珀酸杆的封闭效果,用1-碘丙烷封闭后的芯片进行杂交,芯片杂交信号强、背景噪声低,灵敏度高,整个封闭过程实验操作简单,时间短,1h即可达到所需效果。1-碘丙烷可以作为一种很好的DNA芯片封闭试剂。 相似文献
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提出了一种新的DNA芯片的封闭方法:1-碘丙烷封闭方法,并对1-碘丙烷和琥珀酸酐两种不同的封闭方法的封闭效果进行了比较实验,研究封闭试剂、封闭时间对氨基DNA芯片杂交结果所产生的影响。结果表明: 1-碘丙烷封闭效果明显好于琥珀酸酐的封闭效果,用1-碘丙烷封闭后的芯片进行杂交,芯片杂交信号强、背景噪声低,灵敏度高,整个封闭过程实验操作简单,时间短,1h即可达到所需效果。1-碘丙烷可以作为一种很好的DNA芯片封闭试剂。Abstract: Suggested a new blocking method for DNA microarray: 1- iodo -propane .we compared the difference between the two block reagents and the blocking results in different blocking time. The results showed that 1-I-prppane is batter-blocking reagent than succinic anhydride in DNA chip.1h blocking time is enough for blocking. 相似文献
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DNA分子克隆是基本的分子生物学实验技术,传统的分子克隆方法大多需经过酶切链接过程,但在某些情况下,没有合适的酶切位点往往会成为阻碍克隆进行的障碍.本文描述了一种新的分子克隆方法,称为不依赖酶切和链接的分子克隆(RLIC).利用RLIC,将3种不同大小的DNA片段克隆到3种不同载体,证明了这种方法的有效性和可靠性.由于该方法不受限制性酶切序列限制,省去了酶切连接步骤,因此具有很大的灵活性和简便性,在分子生物学研究方面有广泛应用前景. 相似文献
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一种提取质粒DNA的改良方法 总被引:16,自引:1,他引:16
本文详细介绍了一种改良碱裂解法提取质粒DNA的方法,该法采用NH4Ac代替苯酚和氯份的抽提过程,得率高,质量好,完全达到了分子生物学常规实验的要求,如酶切、连接、转化大肠杆菌、PCR等,甚至用于序列测定和植物遗传转化,该法重复性好,操作简单、实用. 相似文献
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一种提取银杏中DNA的方法 总被引:19,自引:1,他引:19
对改进的SDS和CrAB两种提取DNA的方法进行了比较试验,通过DNA浓度和纯度测定及琼脂糖凝胶电泳检测,结果显示,用改进的SDS法可从银杏幼叶和愈伤组织中获得DNA,其浓度分别为0.867μg·μ 相似文献