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581.
582.
An expression for the partition function of the model including only two parameters-U (energy of hydrogen bond) and Q (the number of conformations of the repeating unit) with Hamiltonian is obtained. This expression has the form of algebraic series with the number of members approximately N3, N being the length of the chain. The results of calculations of the temperature relationship of helicity degree are presented for different values of N. The transition width and the parameter of cooperativity are calculated. 相似文献
583.
mutation Y168H of the human phenylalanine hydroxylase (PAH) gene determining phenylketonuria was described only twice: in a patient from Catalonia (Spain) and by us in a patient from Western Siberia (Russia). The association of Y168H in these families with allelic variants of STR and VNTR repeats and a number of neutral point polymorphisms of the PHA gene (IVS3nt-22C > T, Q232Q, V245V, L385L) was studied in this work. The Y186H mutation in these families was found to be associated with different haplotypes. Strong linkage of the selected markers and the mutation region excludes recombination as a possible cause of association of Y168H with different haplotypes. It was concluded that Y168H occurred independently in different populations. 相似文献
584.
I. I. Ermakova T. A. Chertkova A. L. Mokrushin G. A. Sakuta A. V. Romaniouk V. I. Morozov 《Cell and Tissue Biology》2008,2(5):538-545
Proteoglycans were isolated from the extracellular matrix (ECM) of L6J1 rat myoblasts; their influence on myoblast adhesion has been studied. Proteoglycan digestion with chondroitinase AC and heparinase III, which degrade polysaccharide moieties, has revealed that chondroitin sulfate proteoglycans are a major class of myoblast extracellular matrix proteoglycans. Electrophoresis of enzymatically processed proteoglycans was used to examine their core proteins. Myoblast adhesion was suppressed by proteoglycans or a mixture of proteoglycans and a fibronectin-extracellular matrix. Myoblast adhesion to a substrate composed of fibronectin and proteoglycans is restored after the substrate was treated with chondroitinase AC. In conclusion, proteoglycans of L6J1 rat myoblast ECMs were isolated and purified. Chondroitin sulfate proteoglycans are a major class of proteoglycans. Isolated proteoglycans suppressed myoblast adhesion; the effect was mediated by polysaccharide moieties of proteoglycans. 相似文献
585.
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587.
L A Piruzian Iu E Morozov A V Limantsev V A Lomonosov V A Dement'ev 《Izvestiia Akademii nauk SSSR. Seriia biologicheskaia》1989,(1):35-41
Complicated ecological conditions, caused by wide and active application of artificial chemicals, makes it necessary to reveal their effect on human and animal organism and take measures for protecting health. The possibility to use advanced computing and information devices in combination with specialized methodical approaches allowed to elaborate and build a model of a system for revealing fine and multi-aspect influence of various factors on organisms of experimental animals. The results obtained allow to consider creation of similar systems a necessary and feasible task. 相似文献
588.
589.
tRNA(adenine-1-)-methyltransferase (EC 2.1.1.36) was isolated from the extreme thermophile Thermus thermophilus strain HB8. The specific activity of the enzyme is about 50 000 and the yield of activity more than 20%. The method of isolation consists of five steps and is valid for isolation of mg quantities of the enzyme. The purified protein preparation is practically homogeneous in SDS-gel electrophoresis, the position of the protein band corresponds to a molecular weight of 25 000. By gel filtration on Sephadex G-100 the molecular weight of the native protein was found to be 70 000. These data allow to suggest a subunit structure of the enzyme. The enzyme is highly thermostable and is most active at 80 degrees C. The only activity of the enzyme is to methylate A58 in the T psi X loop of tRNA. 相似文献
590.
T B Kazakova A A Miul'berg S V Burov O I Golovko T V Grishina V M Morozov L Ch Neustroeva G V Gushchin 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(7):89-91
The influence of some immunomodulation peptides SKD, R and L on the interleukin-2 (IL-2) synthesis in T-lymphocytes and possibility of their specific interaction with nucleotide sequences of IL-2 gene were studied. It was firstly shown that peptides R and L specifically interacted with regulatory nucleotide sequences of IL-2 gene and, possibly, play a key role in the immunomodulation actions on the IL-2 production. 相似文献