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81.
Valeeva OA Pastushkov LKh Pakharukova NA Dobrokhotov IV Larina IM 《Fiziologiia cheloveka》2011,37(3):98-102
Human proteome is very plastic, it changes under the influence of various biological factors. It is of big interest to find out how specific factors of an environment, including a long-term isolation affect on urine proteome. The study was conducted during the experiment with 105-day isolation. In the present investigation we collected urine samples from 6 healthy volunteers (26-41 years old). The physical activity, daily rhythms and diet were controlled. Urine samples were fractionated on magnetic beads MB-HIC C8 (MB - hydrophobic-interaction chromatography) with ClinProt robot (Bruker Daltonics) prior to MALDI-TOF mass spectrometer analysis with Autoflex III TOF/TOF (Bruker Daltonics), working in a positive linear mode. 117 peaks have been obtained in each spectrum of urine. We have shown that even during isolation and under controlled conditions of life a high variability of urine proteome of healthy personas (36 protein MC-peaks in the urine, on average) are revealed. 相似文献
82.
Mustafa Kh. Dabbous Ola Hammouda Burcharda Brinkley 《Molecular and cellular biochemistry》1981,34(2):87-93
Summary Limited proteolysis with pepsin solubilized 25% of the insoluble gingival matrix as mainly soluble collagenous material. Fractional
salt precipication at neutral pH resulted in the separation of types III and I at 1.8 and 2.6 M NaCl, respectively. In addition,
a collagenous fraction accounting for 2% of the solubilized collagen and precipitating at 4.5 M NaCl was shown to be identical
with type V collagen. Isolation and partial characterization of the constituent-α-chains of the 4.5 M PPT by gel filtration,
ion exchange and hydroxylapatite chromatography as well as disc electrophoresis showed that gingival type V collagen contains
αA and αB chains in a ratio αB/αA of 1.73–1.8. Electron microscopic examination of ATP-precipitates showed that this collagen
type gave only one kind of SLS aggregates with asymmetric band pattern characteristically different from that of type I collagen.
The data provide evidence that gingival AB collagen is a heteropolymer in which the αA and αB chains are assembled in the
same macromolecule in a 1∶2 ratio. 相似文献
83.
84.
Verkhozina V. A. Verkhozina E. V. Gonchar D. A. Dedkov V. S. Degtyarev S. Kh. Kusner Yu. S. 《Applied Biochemistry and Microbiology》2004,40(4):388-391
Restriction endonucleases (RENs) were detected in 650 microbial strains isolated from water columns and bottom sediments of deep rift lakes, Baikal (Russia) and Nyasa (Southeastern Africa). They enzymes included unique (Fan I, Aca I, and Sse 91) and very rare (Bsi I, and Cci N I) species not typical of aquatic ecosystems. Water columns, deep cores, and bottom sediments of pure areas of the lakes contained no microorganisms with new RENs. Thus, the inshore areas of Lake Baikal, having been exposed to anthropogenic influences, may contain mutant bacterial strains expressing RENs that have not been described previously. 相似文献
85.
Electrophoretic mobility, amino acid composition and salt dissociation of histones isolated from sperm of sea urchin Strongylocentrotus intermedius and calf thymus cells were studied. The special arginine-rich histone fraction (I) has been observed in sea urchin sperm chromatin, this fraction being absent in calf thymus chromatin. Dissociation of lysine-containing histone fractions from sea urchin chromatin occured in the range of 0.7 to 1.0 M NaCl concentrations. H1 of calf thymus chromatin was totally extracted with 0.6 M NaCl. In the course of a further increase of salt concentrations (up to 1.5 M NaCl) a practically total extraction of histones from sperm chromatin was observed, while about 20% of proteins remained bound to DNA in thymus chromatin after extraction with 2.0 M NaCl. The template activity of non-extracted DNP preparations from urchin sperm was equal to 2-3% of that of totally deproteinized DNA. The template activity of DNP gradually increased at protein extraction from DNP preparations. The hybridization capacity of RNA transcribed on partially dehistonized DNP templates in vitro also increased. 相似文献
86.
Khasanov Kh. T. Davranov K. Rakhimov M. M. 《Applied Biochemistry and Microbiology》2015,51(5):600-607
Applied Biochemistry and Microbiology - We demonstrated that a change in the catalytic activity of fungal lipases synthesized by Rhizopus-microsporus, Penicillium sp. and Oospora lactis and their... 相似文献
87.
88.
The purpose of this article is to describe and analyze the edTPA, a performance assessment created by the Stanford Center for Assessment, Learning, and Equity (SCALE) and administered by Pearson, Inc., to assess the professional readiness of student teachers. We challenge claims made in support of using this assessment, specifically within the context of arts teacher preparation programs, and we address areas of immediate critical concern to make alternative recommendations. 相似文献
89.
I. Kh. Kovaleva 《Plasma Physics Reports》2013,39(3):226-235
Conditions for the excitation of small-scale nonlinear ion-cyclotron gradient-drift dissipative structures in cold ionospheric plasma are considered. The solution for the wave electric field in this structure in the form of a chirped soliton satisfying the equation of the Ginzburg-Landau type is derived in the electrostatic approach. The dissipative structure as a whole represents the chirped soliton accompanied by the comoving quasineutral plasma hump. The possibility of the excitation of two modes of this type (the high- and low-frequency ones) in plasma containing light and heavy ion impurities is considered. The role of electromagnetic corrections and the possible contribution introduced by these structures to the transport processes in the ionosphere are discussed. 相似文献
90.