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对DNA分子系统的动力学研究表明,DNA分子系统存在双稳势。激光与DNA作用,可激发DNA分子系统进入混沌状态,从而引起遗传变异。若无激光作用,生物体系是一个稳定体系。 相似文献
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本文通过半导体激光等辐照源对DNA辐照,研究激光、紫外、普通红光对DNA吸收光谱的影响。发现激光(660nm)与紫外(峰值波长254nm)均能使DNA吸收峰值改变,表明它们均能被DNA吸收,与DNA发生作用,从而使DNA构型发生变化,但激光、紫外与DNA作用机理是不同的。而普通红光(峰值波长660nm)对DNA光谱无甚影响,这说明了激光与DNA作用的非线性共振吸收存在。并发现在激光辐照DNA时,激光剂量不同以及DNA溶液浓度不同,对DNA光谱的影响也不同。这些结果对激光育种和激光生物学实验有一定参考价值。 相似文献
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本文对激光与DNA分子相互作用,考虑了随机力作用,建立了DNA分子在激光作用下的Fokker-planck方程(FPE)。分析了DNA分子系统的FPE势函数,对激光育种中的DNA遗传变异的随机不确定性现象进行了解释。 相似文献
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激光的遗传诱变效应的微观机理的量子力学分析 总被引:1,自引:0,他引:1
用量子力学研究了激光对DNA的键(或链)的局域相互作用及激光对DNA分子系统的相互作用的微观机理。研究结果可以解释激光的遗传诱变效应。 相似文献
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利用低功率的He-Ne激光辐照离体质粒DNA,并用离子束和紫外线为对照,分析了质粒DNA的单双链断裂效应。结果表明:He-Ne激光辐照可诱发质粒DNA断裂,且断裂频率辐照剂量增大而提高;He-Ne激光辐照后的质粒超螺旋双链的DNA存活率剂量曲线不同于紫外线和氮离子束。He-Ne激光诱发双链断裂的频率低于氮离子束和紫外线。 相似文献
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本文在庞小峰改进后的Yomosa模型基础上,引进了激光与DNA分子系统作用的非线性方程。 相似文献
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激光作用质粒DNA和小牛胸腺DNA的AFM研究 总被引:3,自引:0,他引:3
激光作用质粒DNA和小牛胸腺DNA产生损伤效应,导致DNA结构变化,利用一种改进的试样制备过程和纳米显微镜--原子力显微镜(AFM)能够获得可重现的激光作用质粒DNA和小牛胸腺DNA的AFM图象,显示它们的特殊的表面结构。 相似文献
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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. 相似文献
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N. P. Vesselkin Yu. V. Natochin 《Journal of Evolutionary Biochemistry and Physiology》2010,46(6):592-603
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 相似文献
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