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991.
N Murakami T Morimoto H Imamura T Ueda S Nagai J Sakakibara N Yamada 《Chemical & pharmaceutical bulletin》1991,39(9):2277-2281
Seven new monogalactosyl diacylglycerols (1-7) and six new digalactosyl diacylglycerols (11-16) were isolated from an axenically cultured cyanobacterium, P. tenue. Their structures were elucidated on the basis of physicochemical evidence and the results of enzymatic hydrolysis using a lipase (from Rhizopus arrhizus). Comparison of antialgal activity for P. tenue between monogalactosyl diacylglycerols (1-8) and digalactosyl diacylglycerols (11-19) revealed that the former showed more potent activity than the latter. 相似文献
992.
Purification and some properties of squalene-2,3-epoxide: lanosterol cyclase from rat liver 总被引:1,自引:0,他引:1
Squalene-2,3-epoxide: lanosterol cyclase was purified from rat liver in five steps as a soluble and homogeneous protein. The purified enzyme showed a single band on SDS-polyacrylamide gel electrophoresis with a molecular weight of 75 kD. In its native state it behaved as a homo-dimer. The isoelectric point of 5.5 and the apparent Km value for (3S)-squalene-epoxide of 55 microM were estimated for the cyclase. 相似文献
993.
A. V. Ponosov 《Journal of Mathematical Sciences》1991,56(3):2492-2496
We study properties of some linear and nonlinear operators which occur in the theory of stochastic differential and integral equations.Translated from Statisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 148–154, 1988. 相似文献
994.
A. I. Bril' V. P. Kabashnikov N. V. Kuz'mina Yu. V. Khodyko 《Journal of Applied Spectroscopy》1991,55(3):934-939
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 3, pp. 478–484, September, 1991. 相似文献
995.
A. M. Lyudchik A. N. Krasovskii L. N. Turyshev L. Ch. Neverovich 《Journal of Applied Spectroscopy》1991,55(3):928-933
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 3, pp. 472–477, September, 1991. 相似文献
996.
997.
A. P. Prudnikov Yu. A. Brychkov O. I. Marichev 《Journal of Mathematical Sciences》1991,54(6):1239-1341
Translated from Itogi Nauki i Tekhniki, Seriya Matematicheskii Analiz, Vol. 27, pp. 3–146, 1989. 相似文献
998.
V. K. Malyutenko A. I. Liptuga V. A. Botte V. I. Chernyakhovskii 《Journal of Applied Spectroscopy》1991,55(4):1024-1028
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 624–629, October, 1991. 相似文献
999.
Summary Considered here are model equations for weakly nonlinear and dispersive long waves, which feature general forms of dispersion and pure power nonlinearity. Two variants of such equations are introduced, one of Korteweg-de Vries type and one of regularized long-wave type. It is proven that solutions of the pure initial-value problem for these two types of model equations are the same, to within the order of accuracy attributable to either, on the long time scale during which nonlinear and dispersive effects may accumulate to make an order-one relative difference to the wave profiles.This research was supported in part by the National Science Foundation. A considerable portion of the project was completed while the first author was resident at the Institute for Mathematics and Its Applications, University of Minnesota. 相似文献
1000.
The stressed state of a thick three-layer plate with two circular holes is studied. Resolving functions are expressed in terms of Kolosov-Muskhelishvili integral potentials and modified Bessel functions. The problem is reduced to solving an infinite set of linear algebraic equations.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 18, pp. 25–28, 1987. 相似文献