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141.
Distribution of isotopic label after the oral administration of free and bound 14C-labelled glucosamine in rats 总被引:4,自引:4,他引:0
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G. B. Robinson 《The Biochemical journal》1968,108(2):275-280
The metabolic fate of [1-(14)C]glucosamine, of N-acetyl[1-(14)C]glucosamine and of glycoproteins labelled with [1-(14)C]glucosamine was studied in rats for a period of 24hr. after these materials were given orally or injected. When [1-(14)C]glucosamine was injected 26.3% of the label was excreted in the urine, 19.7% was expired as carbon dioxide and 12.7% was incorporated into plasma proteins. When the same compound was given orally, 49.2% of the label was expired as carbon dioxide, with little appearing in the urine or in the plasma. When N-acetyl[1-(14)C]glucosamine was injected, 51.3% of the label was excreted in the urine with 12.3% appearing in carbon dioxide, but there was little incorporation into plasma protein. When this compound was given orally, 46.5% of the label was expired as carbon dioxide, 7.4% was recovered in the urine and 1.7% was incorporated into plasma protein. After the injection of (14)C-labelled glycoprotein 21.0% of the label was expired as carbon dioxide, whereas when it was given orally 49.8% of the label was recovered in carbon dioxide. The differences observed between the metabolic fate of the amino sugars when they were given orally and their fate when injected could not be accounted for by the action of the intestinal microflora or by the rate of administration of the material. It is concluded that amino sugars undergo metabolic alteration or degradation during absorption. 相似文献
142.
G. Albin Matson H. Eldon Sutton B. Etcheverry Raul Jane Swanson Abner Robinson 《American journal of physical anthropology》1967,27(2):157-193
This is the fourth paper in a series on the distribution of blood groups among Indians of South America. It reports the findings on the Indians of Chile and the Polynesians of Chile's Easter Island. Blood specimens were procured from the following putatively pure Indians and unmixed Polynesians: 44 Alacaluf of Puerto Eden, Isla Wellington, 141 Mapuche (Araucanian) of Lonquimay, Malleco Province, 80 Atacameños of Antofagasta Province, and 45 Polynesians of Easter Island. These 310 samples were tested for blood factors in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, K-k, Lewis, Duffy, Kidd and Diego systems, and for the Wright (Wra) agglutinogen. Serum samples were tested for haptoglobins and transferrins. Hemolysates prepared from the blood clots were tested for hemoglobin types. The results are presented as phenotype incidences and calculated gene frequencies in appropriate tables. Locations of the populations from which blood samples were procured are shown on two maps. The high frequencies for the O gene usually reported for South American Indians obtain in putatively pure Chilean Indians but A1 is high in Easter Island Polynesians. In both Indians and Polynesians M, s, R1 (CDe), R2 (cDE), Lub, k, LeH, and Fya gene frequencies are high and B, N, S, Mia, Vw, Rº (cDe), r (cde), Lua, K, Le1, Fyb, and Wra (Ca) are low or absent. The Diego (Di) gene is present in the Mapuche and Atacameños but absent in the Alacaluf and Polynesians. Hp1 gene frequencies were determined only in the Alacaluf and Atacameños, in which they are 0.48 and 0.67 respectively. Transferrins were determined for the Alacaluf and Atacameños Indians and all were classified as Tf C. All Chilean Indian and Polynesian specimens were tested electrophoretically for hemoglobin types and all contained only hemoglobin (A) as a major component. 相似文献
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A comparison of autoclaved and gamma-irradiated soils as media for microbial colonization experiments 总被引:2,自引:0,他引:2
Summary The effects on various properties of Lincoln Clay of a sterilizing dose of gamma radiation (3.0 megarads) were compared to the effects resulting from autoclaving the soil (121°C) for 1 hour. Effects of both treatments were much more drastic when moist, rather than air-dry soil was treated but, in general, radiation had less effect on soluble organic matter and on total water-extractable electrolyte than did autoclaving. Radiation caused a greater release of NH4-N from soil treated moist than did autoclaving but the reverse was true in dry soil. Alcohol-soluble ninhydrin-positive material was increased by both sterilization procedures with irradiation having the greater effect. The aggregate stability of Lincoln clay was decreased by irradiation and increased by autoclaving.Pure cultures of bothArthrobacter sp. andPseudomonas sp. grew better, on the basis of cell yields, in irradiated than in autoclaved soil. Respiration of mixed soil organisms in an artificial soil amended with an extract of irradiated soil was almost identical with that in an extract of air-dried soil but auto-claved soil extract was only metabolized after a prolonged lag period.This work was supported by grant # A 1702 from the National Research Council of Canada, Ottawa, Canada. 相似文献
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