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Characterization of B and H blood-group active glycosphingolipids from human B erythrocyte membranes
Peter Hanfland 《Chemistry and physics of lipids》1975,15(2):105-124
Two blood group B active glycosphingolipids (B-I and B-II) previously isolated and highly purified from human B erythrocytes [21] were analysed first by degradation with α-D-galactosidase from coffee beans, α-L-fucosidase from bovine kidney and with 0,1 N trichloracetic acid; the native B-glycolipids as well as their degradation products were then investigated by methylation analysis with combined gas chromatography-mass spectrometry, by thin layer chromatography, twodimensional immunodiffusion and by the hemagglutination inhibition technique. Together with the results obtained by mass spectrometry of permethylated glycolipids [26] the following structures were elucidated: α-D-galactopyranosyl-(1 → 3)-[α-L-fucopyranosyl-(1 → 2)]-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide for the B-I glycosphingolipid and α-D-galactopyranosyl-(1 → 3)-[α-L-fucopyranosyl-(1 → 2)]-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide for the B-II glycosphingolipid. A H active glycolipid fraction from B erythrocytes further purified by thin layer chromatography was also investigated by methylation analysis. The pattern of its partially methylated alditol acetates was essentially the same as that of the α-galactosidase treated and permethylated B-I glycolipid. It also exhibited strongly precipitating and hemagglutination inhibiting H properties as well as the two α-galactosidase treated B-I and B-II glycosphingolipids. Based upon these data the following tentative structure was proposed: α-L-fucopyranosyl-(1 → 2)-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide. Gas chromatographic analysis revealed sphingosine and lignoceric, nervonic and behenic acids to be the main components of the ceramide residues of the three glycosphingolipids. From the data presented the H active substance very probably can be regarded as the immediate precursor of the B-I glycosphingolipid from human B erythrocyte membranes. 相似文献
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利用 XAD-4憎水性吸附树脂采集墨红头香,以毛细管气相色谱双柱保留指数和 GC/MS/DS 联用方法鉴定头香的化学成份。共分离鉴定或初步鉴定了45种组份,其中含量较大的有乙酸芳樟酯(14.98%),柠檬烯(12.07%),甲基苯甲醚(9.88%),香茅醇(4.82%),乙酸巳酯(3.98%),β-石竹烯(4.55%),芳樟醇(3.18%),正巳醇(3.17%)等. 相似文献
5.
Yasuo Ezaki 《Ecological Research》1992,7(1):63-70
Foraging habitat selection of breeding great reed warblers was studied at a shore of Lake Biwa. The foraging grounds of parent
warblers during the nesting period were not restricted to the breeding territory of the reed marsh, their nestling habitat.
The paddy field outside the reed marsh was used communally by them throughout the breeding season. Females with early stage
nestlings did not visit the paddy field whereas when nestlings were older than 3 days, more than half of their total food
was collected there. Females with nests adjacent to the paddy field tended to exploit the paddy field more often than those
with nests distant from it. Monogamously mated females tended to exploit the paddy field more often than polygynously mated
females. Food collected in the paddy field was larger than that in the reed marsh and parent birds were prepared to travel
longer distances to exploit the rich source of food in the paddy field. The importance of the communal foraging ground outside
the reed marsh as a background of the polygynous mating system of this species is discussed. 相似文献
6.
Two population groups of Jammu and Kashmir (India) — Muslims and Bodhs-have been typed for haptoglobin and for CG and PI subtype
polymorphisms. The allele frequencies do not show significant differences between these two populations. HP and GC allele
frequencies of Bodhs and Muslims differ considerably from with that observed in other North Indian populations. The PI allele
frequencies of Bohds and Muslims differ considerably from those found in other Indian populations and are more similar to
Mongoloid ones. 相似文献
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“同时蒸馏-萃取”分析茉莉花香成分 总被引:5,自引:0,他引:5
用一种经过改进的“同时蒸馏-萃取”仪提取了茉莉花的香成分,以 GC/MS 和 Kovats保留指数法鉴定了提取物中的28个化学成分。主要成分为:芳樟醇、乙酸苯甲酯、顺-石竹萜烯、榧烯醇、苯甲酸顺-3-己烯酯、邻氨基苯甲酸甲酯、二十三烯-11及吲哚。讨论了鲜花香成分和植物精油的采集与分析方法。 相似文献
10.
In order to investigate the influence of hapten density and of carrier proteins on the immunological characteristics of antisera, 4 groups of rabbits were injected with different aldosterone-carboxymethoxime protein conjugates. Six animals immunized with an aldosterone rabbit serum albumin (RSA) conjugate carrying 15 steroid molecules (RSA-2 conjugate) showed markedly higher antibody titers than rabbits injected with a RSA conjugate carrying 8 aldosterone molecules (RSA-1 conjugate). Low antibody titers were found in 8 animals immunized with an aldosterone bovine gamma globulin (BGG) conjugate showing a molar incorporation of 15. In a group of rabbits which was first injected with the RSA-1 conjugate and re-immunized with the RSA-2 conjugate the magnitude of antibody production was not enhanced. No differences in antibody sensitivity or specificity were observed between the 4 groups. It was concluded from these experiments a) that the density of haptenic groups depending on the molar incorporation of haptens and on the molecular weight of the carrier protein had influenced the magnitude of antibody production, b) that hapten density or carrier proteins had no effect on antibody sensitivity or specificity, c) that the magnitude of antibody production cannot be altered by re-immunizing with a more potent antigen. 相似文献