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1.
Regional and age-related peculiarities of chromosomal polymorphism are established as a result of studies in C-band heteromorphism of chromosomes 1, 9 and 16 in the long-lived subjects, their relatives and population groups of the Abkhaz and Ukrainian Republics. Heteromorphism frequencies of chromosomes 1 and 9 homologs are higher in the Abkhaz as compared with the Ukrainian Republic. Age-related differences as to the degree of expression of chromosome 9 C-band heteromorphism are found: in the Abkhaz Province the frequency of variants with a high heteromorphism degree increases with age, while in the Ukrainian one--with a low heteromorphism degree.  相似文献   
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A model is proposed which describes the packing of polypeptide chains of histone molecules in the octamer (H3--H4--H2A--H2B)2, and interlocation of DNA and octamer in the nucleosome. DNA packing in the nucleosome is provided for by electrostatic interactions between DNA phosphates and cationic groups located on the globular part surface of histones octamer. The cationic groups of N- and C-end regions of the histone molecules (histones H3 and H4 in particular) additionally stabilize the nucleosome structure.  相似文献   
4.
It was shown that the histone tetramer (H3-H4)2 fluorescence spectra were shifted by about 2 nm towards the long-wave region and had a larger halfwidth than the free tyrosine fluorescence spectra. Denaturation with 8 m urea resulted in a shift towards the short-wave region and a decrease in the halfwidth of the histone tetramer (H3-H4)2 tyrosine fluorescence spectra. Fluorescence quenching of the histone tetramer (H3-H4)2 by iodine ions was analysed by the Stern-Volmer equation. It was estimated that at 0.1 m NaCl and 0.3–0.8 m NaCl, 45% and 60% tyrosyl fluorescence, respectively, was quenched by I? ions. The results obtained suggests that histone tetramer (H3-H4)2 may have several structural forms distinguished by the amount of ‘exposed’ and ‘buried’ tyrosyls depending upon the conditions of the medium.  相似文献   
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本文报告了本实验室设计的由血红细胞自溶液60℃热变性, 乙醇——氯仿法除血红蛋白,旋转蒸发法减压浓缩抽去氯仿、乙醇,硫酸铵分级盐析法沉降SOD,Sepbadex G-75层析提纯SOD等步骤构成的一条成本低、设计合理、简便实用的分离纯化SOD的工艺路线。  相似文献   
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Ecdysterone, its 20-desoxy-derivative alpha-ecdysone, their 2-desoxy-derivatives ecdysterone 2, 3, 22-triacetate and preparation BTI-4 have been studied for their effect on [3H]-thymidine incorporation in different populations of animal and human lymphocytes. It is shown the ecdysteron and its analogs in concentrations of 10(-12)-10(-5) M take considerable stimulating effect on DNA biosynthesis in animal lymphocytes activated by polyclonal mitogens. The concentration of ecdysterone being increased to 10(-4) m one can observe complete inhibition of activating effect of polyclonal mitogens. Effect of the studied ecdysteroids did not considerably depend on their structure. In case of splenocytes the stimulating effect of ecdysterone on DNA biosynthesis is less expressed than in the case of activated thymocytes. Ecdysterone was established to have considerable inhibiting effect on DNA biosynthesis in the culture of activated Con A cells of lymphocytes in the peripheral blood of healthy donors.  相似文献   
7.
Abstract

A class of very potent nucleoside transport inhibitors is present in two molecular forms around physiological pH. We investigated whether the monoprotonated or the unionized species of these molecules binds to this camer protein with higher affinity.  相似文献   
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The study investigates the effects of the 11+ and HarmoKnee injury prevention programmes on knee strength in male soccer players. Under-21-year-old players (n=36) were divided equally into: the 11+, HarmoKnee and control groups. The programmes were performed for 24 sessions (20-25 min each). The hamstrings and quadriceps strength were measured bilaterally at 60°·s-1, 180°·s-1 and 300°·s-1. The concentric quadriceps peak torque (PT) of the 11+ increased by 27.7% at 300°·s-1 in the dominant leg (p<0.05). The concentric quadriceps PT of HarmoKnee increased by 36.6%, 36.2% and 28% in the dominant leg, and by 31.3%, 31.7% and 20.05% at 60°·s-1, 180°·s-1 and 300°·s-1 in the non-dominant leg respectively. In the 11+ group the concentric hamstring PT increased by 22%, 21.4% and 22.1% at 60°·s-1, 180°·s-1 and 300°·s-1, respectively in the dominant leg, and by 22.3%, and 15.7% at 60°·s-1 and 180°·s-1, in the non-dominant leg. In the HarmoKnee group the hamstrings in the dominant leg showed an increase in PT by 32.5%, 31.3% and 14.3% at 60°·s-1, 180°·s-1 and 300°·s-1, and in the non-dominant leg hamstrings PT increased by 21.1% and 19.3% at 60°·s-1 and 180°·s-1 respectively. The concentric hamstrings strength was significantly different between the 11+ and control groups in the dominant (p=0.01) and non-dominant legs (p=0.02). The HarmoKnee programme enhanced the concentric strength of quadriceps. The 11+ and HarmoKnee programmes are useful warm-up protocols for improving concentric hamstring strength in young professional male soccer players. The 11+ programme is more advantageous for its greater concentric hamstring strength improvement compared to the HarmoKnee programme.  相似文献   
10.

Introduction  

Nucleus pulposus (NP) cells have a phenotype similar to articular cartilage (AC) cells. However, the matrix of the NP is clearly different to that of AC suggesting that specific cell phenotypes exist. The aim of this study was to identify novel genes that could be used to distinguish bovine NP cells from AC and annulus fibrosus (AF) cells, and to further determine their expression in normal and degenerate human intervertebral disc (IVD) cells.  相似文献   
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