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971.
L. R. I. Baker P. Ackrill W. R. Cattell T. C. B. Stamp L. Watson 《BMJ (Clinical research ed.)》1974,3(5924):150
In a patient receiving regular dialysis prolonged hypophosphataemia due to aluminium hydroxide therapy resulted in osteomalacia and severe proximal myopathy. Both osteomalacia and myopathy responded to correction of hypophosphataemia without vitamin D therapy. 相似文献
972.
A microsomal preparation prepared from the mucosal lining of canine trachea catalyzed the transfer of galactose from its uridine diphosphate derivative to sialidase-treated ovine submaxillary mucin. Maximal incorporation occurred at 30 mm mn2+. When the concentration of mn2+ in the reaction mixture was reduced to 2.5 mm, approximately two-thirds of the enzymatic activity was lost, but full activity could be restored by the addition of 1 mm spermine. Under these conditions spermine did not affect the Km for UDP-galactose, but lowered the Km for sialidase-treated ovine submaxillary mucin and Mn2+ by a factor of 10. The effect of spermine was abolished with increasing concentrations of Mn2+, and in the absence of the metal, enzymatic activity was lost and could not be restored by the addition of spermine. Spermidine also stimulated activity at low levels of Mn2+, but to a lesser degree than spermine. A slight stimulatory effect was consistently derived from putrescine as well, while cadaverine, putreanine, and monoamines were ineffectual. Spermine had a similar effect on the enzymatic transfer of GalNAc to a protein core acceptor but had little or no effect on the enzymatic transfer of sialic acid to sialidase-treated ovine submaxillary mucin, galactose to N-acetylglucosamine, or fucose to sialidase-galactosidase-treated fetuin. Similar results were obtained with enzyme preparations prepared from canine submaxillary glands. Other polycationic compounds such as protamine, histone, and polylysine also stimulated enzymatic activity at suboptimal concentrations of mn2+. 相似文献
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Studies on the RNA of the mate-killer particles of Paramecium 总被引:2,自引:0,他引:2
R Baker 《Heredity》1970,25(4):657-662