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11.
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EB Nikol'skaia OV Iagodina BA Grinberg MM Dianova 《Canadian Metallurgical Quarterly》1998,70(3):50-56
Isolation of highly purified and highly molecular monoamine oxidase (MAO) from pig liver mitochondria have been worked out. Specific activity of isolated preparation is 2700 times higher than of original mitochondria homogenate. Enzyme solubilization by digitonin, affinity chromatography purification and ultrafiltration underlie this method. MAO catalytic properties changing during the process of purification by different methods have been investigated. Substrate specificity was studied; kinetic parameters of enzymatic desemination were calculated. 相似文献
13.
O. V. Bobreshova A. V. Parshina K. A. Polumestnaya S. V. Timofeev 《Petroleum Chemistry》2011,51(7):496-505
The organization principles of a new type of sensors were developed whose analytical signal is the Donnan potential at the
ion-exchange polymer/test solution interface (PD-sensors) for the determination of organic and inorganic electrolytes in multicomponent
aqueous solutions. It was found that the cross sensitivity of PD-sensors based on perfluorinated, sulfonated cation-exchange
polymers (PSPs) in the initial inorganic forms depends on the potential-determining reactions of protolysis and ion exchange
at the PSP/multicomponent test solution interface. The effects of the hydrophilicity, moisture capacity, and ionic form of
the ion-exchange polymer on PD-sensor sensitivity were investigated. It was found that treatment of PSP with ethylene glycol
at the glass-transition temperature of the polymer makes it possible to obtain modified PSPs in organic forms, which differ
from the initial materials by a larger concentration of dissociated counterions, and thus lead to enhanced PD-sensor response
and sensitivity to an appropriate organic component. Potentiometric multisensor systems including cross-sensitive PD-sensors,
ion-selective electrodes (ISEs), and algorithms for the processing of multidimensional data for the quantitative determination
of lysine, novocaine, lidocaine, thiamine, pyridoxine, nicotinic acid, and alkali and alkaline earth metal cations in multicomponent
solutions were developed. 相似文献
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DW Dawson OV Volpert SF Pearce AJ Schneider RL Silverstein J Henkin NP Bouck 《Canadian Metallurgical Quarterly》1999,55(2):332-338
Mal II, a 19-residue peptide derived from the second type 1 properdin-like repeat of the antiangiogenic protein thrombospondin-1 (TSP-1), was inactive in angiogenesis assays. Yet the substitution of any one of three L-amino acids by their D-enantiomers conferred on this peptide a potent antiangiogenic activity approaching that of the intact 450-kDa TSP-1. Substituted peptides inhibited the migration of capillary endothelial cells with an ED50 of 8.5 nM for the D-Ile-15 substitution, 10 nM for the D-Ser-4 substitution, and 0.75 nM for the D-Ser-5 substitution. A peptide with D-Ile at position 15 could be shortened to its last seven amino acids with little loss in activity. Like whole TSP-1, the Mal II D-Ile derivative inhibited a broad range of angiogenic inducers, was selective for endothelial cells, and required CD36 receptor binding for activity. A variety of end modifications further improved peptide potency. An ethylamide-capped heptapeptide was also active systemically in that when injected i.p. it rendered mice unable to mount a corneal angiogenic response, suggesting the potential usefulness of such peptides as antiangiogenic therapeutics. 相似文献
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LG Yu DG Fernig MR White DG Spiller P Appleton RC Evans I Grierson JA Smith H Davies OV Gerasimenko OH Petersen JD Milton JM Rhodes 《Canadian Metallurgical Quarterly》1999,274(8):4890-4899
The Galbeta1-3GalNAcalpha (TF antigen)-binding lectin (ABL) from the common edible mushroom (Agaricus bisporus) has a potent anti-proliferative effect without any apparent cytotoxicity. This unusual combination of properties prompted investigation of its mechanism of action. In contrast to soluble lectin, agarose-immobilized, and hence noninternalizable ABL had no effect on proliferation of HT29 colon cancer cells. Electron microscopy of HT29 cells incubated with fluorescein- and gold-conjugated ABL showed internalization of the lectin into endocytotic vesicles and multivesicular bodies. Confocal microscopy showed perinuclear accumulation of fluorescein isothiocyanate-conjugated lectin, which also inhibits HT29 cell proliferation, raising the possibility that the lectin might interfere with nuclear pore function. Transport of heat shock protein 70 into the nucleus in response to heat shock was blocked by preincubation of HT29 cells for 6 h with 40 micrograms/ml ABL. In digitonin-permeabilized cells, nuclear uptake of bovine albumin conjugated to a nuclear localization sequence (NLS)-containing peptide was also inhibited by a 15-min preincubation with 40-100 micrograms/ml ABL. In contrast, serum-stimulated nuclear translocation of mitogen-activated protein kinase, which is NLS-independent, was not affected by pretreatment of cells with the lectin. These results suggest that the anti-proliferative effect of ABL is likely to be a consequence of the lectin trafficking to the nuclear periphery, where it blocks NLS-dependent protein uptake into the nucleus. 相似文献
18.
The characteristics of marriages contracted in 1993 in two districts of the city of Khar'kov were studied. The age, education, occupation, ethnicity, and birthplace of the spouses were recorded. The genetic demographic parameters of the marriage structure were compared to the results of a similar study performed in 1985. It was found that since 1985, the average age of marriage and the educational level of spouses had increased, while the ethnic diversity and coefficients of contingency by the spouses' ethnicity and profession had decreased. The contingency coefficient for the birthplace has increased. The causes and genetic consequences of these changes are discussed. 相似文献
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Distribution of T-bands on mitotic chromosomes of Bos taurus was studied. Association of T-bands with telomeres and enrichment of T-bands with genes, with a known localization is described. After THA-banding on the chromosomes of cattle, telomeric and pericentromeric regions of all autosomes showed bright fluorescence. The exception was for chromosome 7, which did not have telomeric T-bands. Interstitial T-bands were detected only on chromosomes 7, 16, and Y (7q13, 7q15, 7q22, 7q24, 16q21, and Yp12). A total proportion of centromeric, telomeric, and interstitial T-bands was 11.19, 9.97, and 2.02% of the length of the haploid chromosome set, respectively. By means of fluorescent in situ hybridization (FISH), the presence of the telomeric repeat (TTAGGG)n was shown not only in telomeric regions of all autosome, but also in all pericentromeric regions. The obtained data are indicative of the specificity of T-banding on the chromosomes of Bos taurus. 相似文献