丹参DNA提取方法比较

为从富含多糖、酚类物质的丹参幼叶中提取高质量的核总DNA,比较了4种DNA提取方法对丹参叶片的提取效果,结果表明改良CTAB法提取的DNA溶液颜色为无色透明、A260/A230为2.137、A260/A280为1.816值最好,是提取丹参基因组DNA的有效方法.     

丹参DNA提取方法比较

为从富含多糖、酚类物质的丹参幼叶中提取高质量的核总DNA,比较了4种DNA提取方法对丹参叶片的提取效果,结果表明：改良CTAB法提取的DNA溶液颜色为无色透明、A260／A230为2．137、A260／A280为1．816值最好,是提取丹参基因组DNA的有效方法。     

野生芋属植物干叶片DNA的提取及PCR扩增

野生芋属植物体内多糖、色素、酚类等次生物质含量较高,严重影响从中提取的DNA的质量.针对这一问题,作者以6种芋属植物的干叶片为材料,摸索出一种适合芋属植物的DNA提取方法,并对提取的DNA进行了纯度鉴定和PCR检测,结果表明此方法可有效去除次生物质对DNA的干扰,样品DNA的质量和纯度较高,可用于下游分子生物学操作.     

野生芋属植物干叶片DNA的提取及PCR扩增

野生芋属植物体内多糖、色素、酚类等次生物质含量较高,严重影响从中提取的DNA的质量。针对这一问题,作者以6种芋属植物的干叶片为材料,摸索出一种适合芋属植物的DNA提取方法,并对提取的DNA进行了纯度鉴定和PCR检测,结果表明此方法可有效去除次生物质对DNA的干扰,样品DNA的质量和纯度较高,可用于下游分子生物学操作。     

应用CTAB法对砂梨品种DNA提取效果的研究

为了获得质量较好的DNA,我们采用CTAB法对11个砂梨品种的叶片DNA提取情况进行了研究,发现参试样品中一些样品的蛋白质含量较多,而另外一些样品的多糖、酚类物质含量较高。对于蛋。白质含量较多的这类材料,适当增加24：1的处理次数能够使蛋白质沉淀下来;对于多糖、酚类物质含量较高的材料,用5mol／L的NaCl和3mol／L的NaAc等处理能够有效的降低多糖含量。另外,对研磨样品的加入量和PVP的加入时间进行了对比,最后用双酶切、电脉检测等不同的分析方法对所得到的DNA提取物的浓度和纯度进行检测,发现加入样品量在0．3g左右、在研磨后的粗提液中加入PVP,所得到的DNA质量较好.     

三种提取蓝猪耳总DNA方法的比较

针对蓝猪耳（Torenia fournieri L.）叶片中多糖、色素等物质严重干扰总DNA提取质量的问题,以蓝猪耳叶片为试验材料,分别采用高盐低pH值法、SDS法、CTAB法提取总DNA,并从样品电泳图谱、纯度、得率等方面对三种方法进行评价。结果表明,CTAB法提取总DNA的产率较高、纯度最好,是蓝猪耳总DNA提取的最佳方法。     

顽拗植物龙眼基因组DNA提取方法的研究

为从顽拗植物龙眼(Dimocarpus longan Lour.)叶片中获得可供后续分子生物学操作的基因组DNA．针对其组织细胞内富含多酚、多糖、单宁及色素等物质的特点,采用改进的CTAB法和SDS法,即在核裂解之前先破碎细胞．将存在于细胞质中的次生物质去除后再裂解细胞桉．结合其它一些改进措施．提取到的DNA沉淀呈纯白色．极易溶解于TE中。两种改进方法的OD260和OD280比值分别达到1.82和1．73,其鲜叶基因组DNA产量分别为103ug/g和127ug／g：RAPD扩增条带清晰,丰富．完全满足后续分子生物学操作的要求,其中改良CTAB方法效果更为理想,与之埘比．传统的CTAB法和SDS法提取到的DNA沉淀呈浅黄色甚至红褐色,很难被TE溶解,其OD260和OD280比值均低于1．5,也得不到扩增产物。     

甘蔗基因组DNA小量提取与大量提取方法研究

甘蔗的叶片中含有大量的多糖、多酚类和RNA等物质,对甘蔗分子生物学实验带来了极大的影响.本研究利用改良的CTAB对甘蔗基因组DNA进行小量提取法与大量提取方法的研究,本方法操作简单,DNA完整性好、产量高、纯度高可满足大部分分子实验的需要.     

一种改良的转基因甘蔗基因组DNA提取方法

用改良的转基因甘蔗基因组DNA提取方法可从少量的转基因甘蔗叶片中简便快速地提取高质量的DNA,有效地去除甘蔗叶片中的多糖、多酚类和RNA等物质。经核酸蛋白测定仪及凝胶电泳分析表明,该改良方法提取的DNA具有典型的DNA分子标准紫外吸收光谱特点,其A260/A280为1．7-1．9,A260/A230为1．8-2．0,叶片的DNA产量为45-60μg(100mg)^-1,适用于对转基因甘蔗进行PCR、酶切和Southern杂交检测分析。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism