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1.
M. S. Tashmukhamedov O. K Zakirova Sh. Ya. Mirzaakhmedov Sh. I. Salikhov I. T. Yakubov M. M. Rakhimov 《Chemistry of Natural Compounds》1994,30(1):97-100
Phospholipase A2 has been isolated fromthe venom of he Central Asian green toad Bufo viridis in the electroophoretically homogeneous state for the first time by biospecific absorption chromatography. The affinity sorbent used was Affi-Gel 10 with covalently bound phosphatidylserine (PDS). The chemical inertness of the bound PDS to the hydrolytic action of phospholipase A2 and its high tendency to form biospecific complexes have been shown. Some biochemical characteristics of the enzyme isolated have been studied: influence of the pH and of the Ca2+ concentration and dependence of activity on substrate concentration.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Tashkent State University, fax 462472. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 105–109, January–February, 1994. 相似文献
2.
A theorem on the presentability of a multiple integral as a linear form in 1, ζ(3), ζ(5),..., ζ(2k − 1) over ℚ is proved. This theorem refines the results recently obtained by D. Vasiliev, V. Zudilin, and S. Zlobin.
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Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 6, pp. 143–178, 2005. 相似文献
3.
Chiral diphosphine ligands based on camphor: synthesis and applications in asymmetric hydrogenations
The synthesis of a novel class of atropisomer chiral diphosphine ligands with a bornene framework is described. The new ligands showed in Rh catalyzed asymmetric hydrogenation of α- and β-enamides very high ee’s (more than 99%). 相似文献
4.
5.
N. A. Sosnina Z. Golbenko A. A. Akhunov Ya. S. Ziyaev Sh. I. Salikhov 《Chemistry of Natural Compounds》1989,25(5):596-599
A bradykinin-potentiating peptide has been isolated from the venom of the spiderLatrodectus tredecimguttatus. Its physicochemical properties and amino acid composition have been investigated in detail. It has been shown by biological testing on isolated neck of the rat uterus that the peptide increases the contractile effect of bradykinin in in vitro experiments. The “potentiating unit” is 2 · 10?3 mg/ml. A 50% increase in the hypotensive effect of bradykinin at a concentration of the bradykinin-potentiating peptide of 15 µg/kg of body weight has been found, the increase in the intensity of the effect being accompanied by a prolongation of its action. 相似文献
6.
V. S. Abdukakharov U. A. Turakhanov M. M. Kasymzhanova A. S. Korneev Sh. I. Salikhov A. A. Abduvakhabov 《Chemistry of Natural Compounds》1994,30(1):130-132
A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 137–139, January–February, 1994. 相似文献
7.
For a model system of two nonequivalent nuclei with spin 1/2, the NMR spectrum of one of the nuclei has been calculated under conditions of pumping of the second spin, and a study has been made of the spectral transformation upon changing the times of transverse and longitudinal relaxation of both spins. It has been established that the form of the spectrum undergoes qualitative changes. An increase in the rate of transverse relaxation not only broadens the observed lines, but simultaneously changes the character of motion of the spins in the pumping field: With increasing relaxation rate, the motion is converted from coherent motion (nutation) to incoherent motion (transitions between levels, saturation effect). Transformations of the spectrum are related specifically to these changes.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 23, No. 4, pp. 436–443, July–August 1987. 相似文献
8.
N. P. Grechkin N. A. Buina I. A. Nuretdinov S. G. Salikhov 《Russian Chemical Bulletin》1968,17(9):2022-2024
Conclusions The reactions of amides of arylphosphorous acids with acyl chlorides take place with replacement of the amide group and formation of amides of carboxylic acids and the corresponding aryl chlorophosphates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2131–2133, September, 1968. 相似文献
9.
A. R. Al'-Sufi G. R. Bulka V. M. Vinokurov I. N. Kurkin N. M. Nizamutdinov I. Kh. Salikhov 《Russian Physics Journal》1993,36(6):555-559
In this paper, we present detailed studies of the EPR spectra of Cu2+ ions in single crystals of ZnSeO4·6H2O. We describe the spectrum with a rhombic spin Hamiltonian with the following parameters: gz=2.427; gy=2.095; gx=2.097; A z 65 =138.4·10?4 cm?1; A x 65 =22.3·10?4 cm?1. We studied spin-lattice relaxation in the temperature range 4–300 K at the frequency v≈9.3 GHz. The measured spin-lattice relaxation rate for the orientation H∥L4 is described well at T<5 K by a linear dependence, while at T>5 K it is described by the sum of three exponentials: $$T_1^{ - 1} = 0.27T + 3.3 \cdot 10^{\text{s}} \exp \left( {\frac{{ - 69.5}}{T}} \right) + 2.6 \cdot 10^7 \exp \left( {\frac{{ - 140}}{T}} \right) + 1.36 \cdot 10^{10} \exp \left( {\frac{{ - 735.6}}{T}} \right){\text{ sec}}^{{\text{ - 1}}} $$ .We discuss possible reasons for the exponential dependence of T 1 ?1 for the Raman process. 相似文献
10.