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Unjustified narrowing of the problems of morphology by merging the terms "morphology" and "anatomy" leads to stagnation in morphology. The merging of "classic" and "modern" biology will enrich both morphology and molecular biology and genetics. The latter will be able apply conceptual models of morphology to more primitive structural level of life. The possibility to apply V. A. Dogel' 's ideas on the role of oligomerization and polymerization in science to the analysis of molecular evolution has been demonstrated with the analysis of DNA content in the genomes of Chordata taken as an example. The data on DNA content do not allow both to consider lungfishes as ancestors of all Tetrapoda and develop monophyletic concept of Tetrapoda origin at the same time. The possibility of application of concepts of comparative morphology to analysis of molecular evolution has been considered.  相似文献   
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Isolated myosin heads (HMM-S1) were concentrated by ultrafiltration in an "Amicon" cell to a concentration of 120 mg/ml. Incubation of HMM-S1 with ATP in the presence of Mg2+ produced an AMP peak in the spectrum of NMR-31P whose size was increasing linearly with the reaction time. It was demonstrated that after heating of the sample the appearance of AMP in the incubation mixture was due to the presence of a small amount of adenylate kinase (or myokinase) in the purified preparation of HMM-S1.  相似文献   
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29 individuals of Apodemus peninsulae, an Asian forest mouse from the Suputin State Nature Reserve (Maritime Territory) were studied karyologically. Diploid chromosome sets of the animals studied contained from 48 to 52 chromosomes. The difference in the diploid chromosome numbers is caused by the presence in some individuals of supernumerary metacentric chromosomes (up to 4). The set is always represented by 48 acrocentric chromosomes, gradually decreasing in size. The supernumerary metacentric chromosomes vary in size from medium-sized to the smallest in the set. The character of intrapopulational chromosome polymorphism of continental and island populations of Apodemus peninsulae is discussed. Attempts are made to explain the polymorphism with respect to supernumerary chromosomes as the result of some viral diseases.  相似文献   
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Polyamidoamine (PAMAM) dendrimers of the second generation (G2) are branched polymers containing 16 surface amino groups that allow them to be used as universal carriers on creating systems for drug delivery. G2 labeled with fluorescein isothiocyanate (FITC) efficiently bound with the surface of tumor cells at 4°C and was absorbed by the cells at 37°C. The covalent binding to G2-FITC of a vector protein, a recombinant fragment of the human alpha-fetoprotein receptor-binding domain (rAFP3D), increased the binding and endocytosis efficiency more than threefold. Covalent conjugates of G2 with doxorubicin (Dox) obtained by acid-labile linking of cis-aconitic anhydride (CAA) without the vector protein (G2-Dox) and with the vector protein rAFP3D (rAFP3D-G2-Dox) were accumulated by the tumor cells with high efficiency. However, a selective effect was observed only in rAFP3D-G2-Dox, which also demonstrated high cytotoxic activity against the human ovarian adenocarcinoma SKOV3 cells and low cytotoxicity against human peripheral blood lymphocytes. Based on these results, rAFP3D-G2 conjugate is promising for selective delivery of antitumor drugs.  相似文献   
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The necessity and effectiveness of introducing the program of the exchange of syringes for intravenous drug users as a preventive and antiepidemic measure are discussed. Preventive and antiepidemic measures within the concept of harm reduction are described. The comparative analysis of materials obtained as a result of two sociological questionings, carried out in 1997-1998 among the representatives of the community (random nonrepeating choice) and in the middle of 1999 among the participants of the program revealed that the participants of the program had statistically significant changes in risky behavior patterns during the use of injection drugs.  相似文献   
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An Escherichia coli strain producing transposase of a repeated sequence of Bordetella pertussis chromosome (RSBP) was constructed. A defective MGE-helper plasmid method, which allowed the determination of transposase functional activity was developed. It was shown that transposase synthesized in E. coli cells ensures transposition of “defective” RSBP into the host chromosome. Overexpression of transposase was shown to markedly decrease the vital activity of E. coli cells under selective cultivation conditions. Reasons for a decrease in viability transposase-producing cells are discussed. Results showing the impact of transposase on replication of recombinant plasmids and E. coli cell division were obtained.  相似文献   
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