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71.
S. Jane Darnton 《Cell and tissue research》1969,102(2):273-282
Summary Tritiated glucose has been injected into rabbits in various states of hydration. The renal papilla of all animals showed an uptake of the label, converted into glycogen, and into mucopolysaccharides, in a manner dependent on the water balance of the animal.In papillae of control animals, the glycogen of the collecting duct epithelial cells and the mucopolysaccharides of the interstitium were labelled.In papillae of animals in an aqueous diuresis, the collecting duct glycogen was lightly labelled and there was no label over the interstitium.Antidiuretic hormone caused a diversion of label from the collecting ducts into interstitial mucopolysaccharides.The significance of these findings, with respect to renal concentrating ability, is discussed.The author wishes to thank Dr. M. K. S. Hathorn for help with the statistical analysis. Mr. K. Gamblin and Mr. P. L. Hyam gave valuable technical assistance. This research formed a part of the work approved for the degree of Ph. D. (London). 相似文献
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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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SPERMIOGENESIS IN WILD TYPE AND IN A MALE STERILITY MUTANT OF DROSOPHILA MELANOGASTER 总被引:3,自引:1,他引:2 下载免费PDF全文
Jane Rearick Shoup 《The Journal of cell biology》1967,32(3):663-675
Spermiogenesis in the translocation heterozygote T (1; 2H) 25(20) y l 25/FM6 has been studied with the electron microscope and compared with that in wild type males. It appears that the genetic lesion in the male sterility mutant is associated primarily with a failure in differentiation of the head. In wild type flies, the spermatid nucleus assumes a conchoidal shape; chromatin accumulates along the convex surface. Adjacent to the concave surface a large bundle of microtubules runs parallel to the long axis of the spermatid. A single row of microtubules is juxtaposed against the convex surface of the head. As differentiation proceeds, the nucleus elongates, chromatin condenses, and the nucleus is compacted to a final diameter of about 0.3 µ. In the sterile mutant the spermatid nucleus has an irregular or wedge-shaped profile and no concavity is formed, nor is the bundle of microtubules observed. The row of microtubules, however, is usually present around the periphery. The change from lysine-rich to arginine-rich histone in mature wild type sperm does not occur in the sterile male. The substructure of the axial filament and mitochondrial derivatives, however, are similar to those in wild type. 相似文献
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Ethionine at concentrations of 10−3M, 5×10−3M and 10−2M inhibits growth, both of β-galactosidase inducible ML-30 and constitutive ML-308Escherichia coli strains. The protein synthesis (measured by the incorporation of l-leucine-14C and l-aspartic-14C acid into proteins) of these strains is inhibited to the same extent as their growth. The synthesis of inducible and constitutive
β-galactosidase produced by the strains ML-30 and ML-308, respectively, is considerably inhibited by ethionine. 相似文献
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Bowles, Jean A. (University of Colorado School of Medicine, Denver), and William Segal. Kinetics of utilization of organic compounds in the growth of Mycobacterium tuberculosis. J. Bacteriol. 90:157-163. 1965.-To obtain a workable system for a study of the kinetics of nutrient utilization (based on specific quantitative assay) by Mycobacterium tuberculosis, several cultural refinements were introduced: the use of shake culture, a 40-fold increase in the size of inoculum, substitution of glutamate for asparagine as nitrogen source, and elimination of glucose from the medium with glycerol remaining as carbon source. These modifications resulted in reduction to a tenth of the lag phase of glycerol utilization (from 40 to 4 days), and in a greatly increased rate of growth. Both coordinate and sequential patterns of nutrient utilization were in evidence, except in the case of citrate, which was never utilized under a variety of conditions of culture. The coordinate pattern of glucose-glutamate and glucose-glycerol utilization would appear to rule out catabolite repression by glucose. However, elimination of glucose from the medium resulted in elimination of the 4-day lag period before glutamate utilization was initiated, leaving open to question the role of glucose in this system. Evidence is presented for the hypothesis that the sequential pattern of glutamate-glycerol utilization is a function of glutamate repression of glycerol oxidation in the growth of M. tuberculosis, although no diauxie effect is apparent. In a determination of which nutrient-utilization systems were regulated by induction, only in the case of glycerol was evidence obtained for an inducible system. The enzymatic mechanisms underlying these patterns of nutrient utilization are presently being investigated. 相似文献