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1.
Six vasoactive peptides have been isolated in the homogeneous form from the venom of the waspPolistes gallicus. Their physicochemical characteristics have been investigated. The wasp kinins exhibit myotropic and hypotensive effects. One of the kinins shows a prolonged hypotensive action.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 564–568, July–August, 1989. 相似文献
2.
V. M. L'vov A. A. Kolmakova A. A. Akhunov I. F. Mukhamedov 《Chemistry of Natural Compounds》1988,24(2):218-221
Two peptides having kinin activity have been isolated from hornet venom. The peptides isolated exhibit hypotensive action and a myotropic effect, and they also liberate histamine from mast cells. One of the peptides is a close structural analog of bradykinin while the other differs considerably from it.Institute of Bioorganic Chemistry of the Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 255–258, March–April, 1988. 相似文献
3.
A. M. Mukhamedov 《Russian Physics Journal》1978,21(11):1479-1482
The problem of specifying the symmetry properties of a charged fluid in space-time V4, which has a definite group of motions, is considered. It is shown that if nonempty spacetime V4 with an energy-momentum tensor for the charged fluid has symmetry (i.e., admits a group of motions), then the mass density, the pressure, and the four-velocity of the fluid inherits this symmetry, and for an electromagnetic field the relationL
f
ij
=7.*f
ij
is satisfied. The necessary and sufficient conditions are found so that =0 in the case of a one-parameter group. Then additional relationships between and the structure constants are obtained in the case of an r-parameter group. It is shown that under certain conditions the symmetry properties obtained for charged matter are necessary and sufficient conditions for the symmetry of space-time V4.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 113–117, November, 1978. 相似文献
4.
The paper is devoted to the study of elliptic quadratic operator equations over the finite dimensional Euclidean space. We provide necessary and sufficient conditions for the existence of solutions of elliptic quadratic operator equations. The iterative Newton-Kantorovich method for stable solutions is also presented.
相似文献5.
J. M. Ashurov N. S. Mukhamedov B. Tashkhodzhaev B. T. Ibragimov 《Journal of Structural Chemistry》2015,56(6):1148-1153
The crystal structure of α-(N-benzoxazoline-2-one) acetic acid is studied in the following forms: hydrate, solvate with formic acid, organic monoethanolammonium salt (NН2(CH2)2OH) in two polymorphs produced by minor changes in the crystallization temperature, and also its ethylenediammonium salt (NН2(CH2)2NH2) in the 2:1 ratio, where amino groups participate in the deprotonation of two molecules of α-(N-benzoxazoline-2-one) acetic acid. Weak intermolecular hydrogen and dative bonds in the crystals consisting of different molecules are analyzed. 相似文献
6.
7.
Farruh M Mukhamedov 《Indagationes Mathematicae》2004,15(1):85-99
We consider a nearest-neighbor p-adic Potts (with q ≥ 2 spin values and coupling constant J ? p) model on the Cayley tree of order k ≥ 1. It is proved that a phase transition occurs at k = 2, q ? p and p ≥ 3 (resp. q ? 22, p = 2). It is established that for p-adic Potts model at k ≥ 3 a phase transition may occur only at q ? p if p ≥ 3 and q ? 22 if p = 2. 相似文献
8.
We present necessary and sufficient conditions for the validity of a regularity condition for homogeneous quantum quadratic stochastic processes defined on von Neumann algebras. 相似文献
9.
J. M. Ashurov L. Yu. Izotova B. T. Ibragimov N. S. Mukhamedov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(1):106-110
Two crystalline polymorphic forms of α-(N-benzoxazolin-2-one)acetic acid (BAA) are prepared by changing the temperature of its crystallization from solution in ethanol. Crystallographic data of the α-form are determined: a = 12.7769(17) Å, b = 8.2574(9) Å, c = 16.7390(19) Å, β = 105.087(13)°, space group C2/c, V = 1705.2(4) Å3, and Z = 8, while those of β form are a = 5.2854(4) Å, b = 5.9880(4) Å, c = 13.4509(5) Å, β = 94.666(4)°, space group P21, V = 424.30(4) Å3, and Z = 2. It is found that BAA molecules of the α form combine into infinite one-dimensional chains arranged along axis b by means of O?H···O and C?H···O hydrogen bonds, and these chains are crosslinked via C?H···O hydrogen bonds to form a threedimensional structure. The β form has another system of hydrogen bonds, one of which is bifurcated (O4···O2, O4···O3), and the π–π-interactions between the benzoxazolinone fragments of BAA molecules combined into a chain also arranged along axis b are observed. Calorimetric analysis shows that the polymorphic transition from the α form to the β form occurs at 129°C. 相似文献
10.
Kh. M. Shakhidoyatov T. F. Ibragimov N. S. Mukhamedov 《Chemistry of Natural Compounds》2010,46(4):598-599
4-Butyl-4-hydroxydeoxypeganine was prepared by lithiation of deoxyvasicinone. Deoxypeganine and 1,2-dihydrodeoxypeganine were
produced by reduction of deoxyvasicinone with lithium aluminum hydride. 相似文献