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871.
We report that membrane vesicles of Escherichia coli contain protein-binding sites for acyl carrier protein. Scatchard analysis of the binding indicates a dissociation constant around 0.35 micrometers and a maximum number of protein-binding sites around 50 pmol per mg of membrane protein. Binding is on the inner membrane while the outer membrane is devoid of binding sites. These results are consistent with the fact that some acyl carrier protein-dependent enzymes implicated in phospholipid- and membrane-derived oligosaccharide biosynthesis are localized in the cytoplasmic membrane. 相似文献
872.
A A Sergeev Iu G Chernukha K L Shakhanina Z A Gol'denshte?n E Ia Potashnikova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(7):66-71
The possibility of using the enzyme-linked immunosorbent assay (ELISA) for the diagnosis of leptospirosis has been shown. This method has proved to be more simple and sensitive than the leptospiral microagglutination and lysis test. The data on obtaining genus-specific leptospiral antigens are presented. As revealed in this study, the antigens obtained by the complex treatment of microbial cells with ultrasound and detergents show the maximum activity in ELISA. The optimum parameters of the ELISA system for the diagnosis of leptospirosis have been established. 相似文献
873.
N. N. Tzvelev 《The Botanical review》1989,55(3):141-203
Originally published in Russian as number 37 of Komarov Readings, 1987. Translated by Victoria V. Michaelova, Brigham Young
University, Provo, Utah 84602. Translation edited by Arthur Cronquist, New York Botanical Garden, New York, and approved by
the author. A few additions have been made to account for very recent literature. 相似文献
874.
Iu V Kotelevtsev D D Spitkovski? S N Orlov Iu V Postnov 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(11):608-609
26 male F2 hybrids between spontaneously hypertensive (SHR) and normotensive control (WKY) rats (SHRxWKY)F2 were segregated according to their c-src genotype into SS and WW homozygous groups, corresponding to SHR or WKY and WS heterozygous group. Na, K cotransport in erythrocytes in the WW group was equal to that of WKY and differs significantly from that of WS and SS groups (the rate of Na, K cotransport in latter groups was close to that of SHR). Ca content of RBC in WW group was equal to that of WKY, lower than that of WS and SS groups which in turn was significantly lower than in SHR, indicating polygenic control of the trait. Authors conclude that the c-src locus itself or some other loci inherited in conjunction with c-src determines both the increase of Na, K cotransport and calcium content in erythrocytes of SHR. 相似文献
875.
The behavioral effects of opiate agonists and antagonists were studied on the female aggression model. Mu-agonist buprenorphine more selectively decreased maternal aggression than kappa-agonist tifluadom. Kappa-agonists (bremazocine, tifluadom) increased passive defence in lactating female rats. Ethopharmacological data shows predominant involvement of brain mu-opiate receptor system in the integrative processes of maternal behavior and maternal aggression in particular. 相似文献
876.
L V Lyzlova B L Vo?tsekhovski? K B Grabovskaia A A Totolian 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(7):7-12
The work shows that fibronectin obtained from human plasma is capable of binding with streptococci of different groups with almost equal effectiveness. Fibronectin bound to bacterial cells inhibits the adhesion of group A streptococci onto vaginal cells, but it produces no effect on the adhesion of group B streptococci. The binding constant of fibronectin 125I is equal to 10(6) -M-1, which indicates that the level of the specificity of interaction is not sufficiently high. 相似文献
877.
Using the imidate procedure, 2,3,4,6-tetra-O-benzyl-1-O-(N-methylacetimidoyl)-β-d-galactopyranose was condensed with various monosaccharides to provide, in good yield and with high stereoselectivity, α-linked disaccharides. 相似文献
878.
879.
A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases. 相似文献
880.
Summary The a-c electrical properties of bipolar membranes separating equal strength solutions of the same uni-univalent electrolyte are analyzed for the case where both ions have equal mobilities. Two membrane models are treated. In one, the fixed-charge density is assumed to be constant throughout the membrane. In the other, the membrane is regarded as comprising an array of pores separated by walls through which the fixed charge is spread uniformly. Experimental results are reported for the a-c electrical properties of a bipolar membrane prepared from a single polyolephine sheet and immersed in KCl solutions of various concentrations. It is found that the data can be interpreted using the pore model. 相似文献