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91.
V. K. Rybal’chenko G. V. Ostrovskaya I. V. Poralo T. V. Rybal’chenko Yu. M. Mel’nik 《Neurophysiology》1999,31(3):223-225
On modeled monolayer phospholipid (formed from azolectin) membranes, we studied the surface activity of optical isomers of
a dipeptide, kyotorphin (Tyr-Arg), and a cardiotonic agent, suphan (N-succinyltryptophan potassium salt). It was found that
the membranotropic activity of four studied isomers of kyotorphin is distributed in the order: LL>DL≈LD>DD, and two isomers
(by tryptophan) of suphan as LL>DL. The data obtained suggest that the primary mechanism underlying binding of kyotorphin
and suphan to the plasma membrane can be considered based on interaction of their molecules with the molecules of membrane
phospholipids. Binding of molecules of kyotorphin and suphan by the lipid matrix to the plasma membrane and/or their incorporation
into the matrix is a result of the above interaction. 相似文献
92.
Tong Xie Linda Yu Martin W Bader James C A Bardwell Chang-An Yu 《The Journal of biological chemistry》2002,277(3):1649-1652
Disulfide bond (Dsb) formation is catalyzed in the periplasm of prokaryotes by the Dsb proteins. DsbB, a key enzyme in this process, generates disulfides de novo by using the oxidizing power of quinones. To explore the mechanism of this newly described enzymatic activity, we decided to study the ubiquinone-protein interaction and identify the ubiquinone-binding domain in DsbB by cross-linking to photoactivatable quinone analogues. When purified Escherichia coli DsbB was incubated with an azidoubiquinone derivative, 3-azido-2-methyl-5-[(3)H]methoxy-6-decyl-1,4-benzoquinone ([(3)H]azido-Q), and illuminated with long wavelength UV light, the decrease in enzymatic activity correlated with the amount of 3-azido-2-methyl-5-methoxy-6-decyl-1,4-benzoquinone (azido-Q) incorporated into the protein. One azido-Q-linked peptide with a retention time of 33.5 min was obtained by high performance liquid chromatography of the V8 digest of [(3)H]azido-Q-labeled DsbB. This peptide has a partial NH(2)-terminal amino acid sequence of NH(2)-HTMLQLY corresponding to residues 91-97. This sequence occurs in the second periplasmic domain of the inner membrane protein DsbB in a loop connecting transmembrane helices 3 and 4. We propose that the quinone-binding site is within or very near to this sequence. 相似文献
93.
An algorithm is proposed for extracting regulatory signals from DNA sequences. The algorithm complexity is nearly quadratic. The results of testing the algorithm on artificial and natural sequences are presented. 相似文献
94.
95.
V. V. Dvorkin N. N. Dzbanovskii P. V. Minakov N. V. Suetin A. Yu. Yur'ev 《Plasma Physics Reports》2003,29(9):789-795
Optical emission spectra from the microwave discharge plasma that is used to activate gas-phase deposition of carbon films are systematically investigated under various deposition conditions. The line emission intensities from CH and C2 radicals, which are responsible for the growth of the diamond and graphite phases, respectively, are studied as functions of the main macroparameters of the process. To find the relation between the features of the emission spectra and the composition of the films obtained, the films were examined using Raman spectroscopy and electron microscopy. It is shown that monitoring the relative intensities of the spectral lines can be used to obtain the desired type of film, in which case the state of the substrate surface and the presence of a catalyst on it also play an important role. Experiments on the deposition of carbon films in the pulsed regime of plasma excitation show the possibility of changing the phase composition of the film by varying both the pulse repetition rate and the off-duty factor. At the same average microwave power, the rate of film deposition in the pulsed regime of plasma excitation is lower than that in a continuous discharge; however, the growth rate of the graphite phase decreases insignificantly. 相似文献
96.
Echocardiography was used to study the parameters of cardiodynamics, systemic hemodynamics, left ventricular morphology and functioning, phase analysis of cardiac activity, and rheological blood properties in highly skilled expert swimmers. The relationship between different levels of blood circulation was established. A close correlation between the blood flow at rest and arterial pressure was found to contribute to the optimization of microvascular pressure and shear stress in accordance with body demands. 相似文献
97.
Yu. V. Mamkaev 《Biology Bulletin》2009,36(2):98-106
Different approaches to evolutionary interpretation of ontogenies are compared, with special emphasis on the evolutionary role of morphogenetic mechanisms (construction technologies) substantially affecting the structure of definitive forms: they largely determine the structural characteristics of organs, types of anatomical and histological systems, and specificity of symmetry of organisms and their parts. The role of cellular morphogenesis inherited from protozoan ancestors in the morphogenesis of multicellular organisms is demonstrated. Two main ways of improving morphogeneses are considered, based on epithelial morphogenesis and early determined few-celled primordia. On the one hand, the phylogenetic role of archallaxes and deviations is emphasized, these events often switching evolution to a fundamentally new direction. On the other hand, many characteristics of developmental stages are explainable by rationalization of morphogeneses and do not recapitulate ancestral forms, which should be taken into consideration in phylogenetic interpretation of embryogeneses; in particular, this applies to interpretation of axial relationships. 相似文献
98.
M. Yu. Kordyukova O. V. Zatsepina M. A. Polzikov 《Applied Biochemistry and Microbiology》2011,47(2):123-127
cDNA of human gene Surf-6 (hSutf-6) was amplified and cloned into vector pGEX-2T for the expression in the bacterial system of protein hSURF-6 translationally
fused to glutathione-S-transferase. The resulting vector is named as pGEX-2T-GST-hSurf-6. Superproducer of chimeric protein
GST-hSURF-6 was obtained on the basis of Escherichia coli strain BL21-CodonPlus(DE3)-RIL. Its purification was performed by the affinity chromatography on L-glatathione-sepharose.
The proportion of recombinant protein GST-hSURF-6 in the optimized conditions was not less than 15% of the total bacterial
protein, and up to 7 mg of the protein was isolated from 1 liter of culture of the producer strain. The final fraction of
eluate contained approximately 80% of GST-hSURF-6. The amount and the purity of the isolated protein were sufficient to immunize
animals and obtain antibodies. Protein GST-hSURF-6 can also be used as an affinity ligand for revealing protein partners of
hSURF-6 in human cells. 相似文献
99.
100.
V. A. Dubrovskii B. A. Dvorkin I. Yu. Yanina V. V. Tuchin 《Cell and Tissue Biology》2011,5(5):520-529
The effect of a change in the optical properties of human adipose tissue cells in vitro after photodynamic action was studied
experimentally. The study of kinetics of this process was carried out based on the digital microscopy of thin layers of tissue.
The statistical computer processing of the obtained microimages has allowed one to quantitatively estimate the kinetics of
the photodynamic after effects on the biotissue. The optical interpretation of images indicates that the observed phenomenon
corresponds to the partial lysis of the adipose tissue cells without their complete destruction. 相似文献