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991.
992.
Biochemical and hormonal effects of oral calcium supplementation in premature and asphyxiated neonates during the first few days of life are described. Eight pairs of infants were matched for gestational age and one-minute Apgar score. One member of each pair served as a control and the other was given supplemental oral calcium (75 mg/kg/24 hr) beginning at 12 and ending at 72 hours of age. The supplemental infants had significantly higher serum calcium values both during the time of supplementation and for 36 hours after supplementation was stopped. The oral calcium supplements had no significant effect on serum concentrations of phosphate, magnesium, 25-hydroxy-vitamin D3, or parathyroid hormone, The incidence of hypocalcemia after 12 hours of age was 0 in eight supplemented infants and three in eight control infants. In patients at risk for hypocalcemia, prospective use of oral calcium supplements during the period when there is inadequate calcium intake from feedings may prevent hypocalcemia, appears to be without deleterious effect on measurable chemical and hormonal factors important in calcium homeostasis, and results in maintenance of higher serum calcium levels after supplementation has been discontinued. 相似文献
993.
MM Anisimov SI Baranova LI Strigina NS Chetyrina IN Sokol'ski? 《Canadian Metallurgical Quarterly》1977,22(9):837-841
The effect of triterpen glycosides of cauloside C from Caulophyllum robustum, theasaponine from Thea sinensis ahd stichoposide A from Stichopus japonicus on multiplication and biosynthesis of RNA in the cells of a 7-hour culture of Saccharomyces carlsbergensis was studied. It was shown that cauloside C, theasaponine and stichoposide A in concentrations of 7.5 gamma/ml inhibited multiplication of the yeast cells by 65, 10 and 90 per cent respectively. The summation RNA of the yeast cells is divided into 3 zones on Sephadex G-100. The glycosides induced no pronounced changes in the chromotographic profile of RNA. Biosynthesis of the transport and ribosomal RNA were inhibited to the same extent. Triterpen glycosides inhibited the biosynthesis of RNA at the stage of 14C-uridine in corporation into the nucleotide pool of the yeast cells. 相似文献
994.
MM Lieber 《Canadian Metallurgical Quarterly》1976,34(1):93-122
Previous work has shown that strains of Aspergillus nidulans with a chromosome segment in duplicate (one in normal position, one translocated to another chromosome) are unstable. Deletions occur from either duplicate segment. The present work has shown that most deletions occur from the translocated duplicate segment. Furthermore, it has been found that the overall frequency of deletions from a duplication is dependent upon the temperature of growth. The overall frequency of deletions from a chromosome III duplication is greatly enhanced by low temperatures, while the overall frequency of deletions from a chromosome I duplication is markedly enhanced by high temperatures. A temperature of 39.5 degrees C appears to enhance to overall frequency of deletions from the I duplication to the greatest extent. With regard to the non-translocated duplicate I segment, an increase in temperature progressively enhances the frequency of those deletions to which it is subject to far more deletions during a particular period of growth than during any other period, and at 42 degrees C, a section of the III duplication is subject to far more deletions during a given period of growth than during any other period. Comparisons with other cases of genetic instability are made and common underlying connections are proposed. 相似文献
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Vascularity of the breast was assessed from Xeromammograms by calculating the venous diameter ratio (ratio of the diameter of the largest vein in either breast to the diameter of a comparable vein in the opposite breast) for 60 patients (32 carcinomas and 28 benign conditions). Vein diameter was easier to measure on Xeromammograms than on conventional mammograms. If the venous diameter ratio was 1.4:1, or greater, the possibility of malignancy was increased. 相似文献
1000.
JM Kremer MM Kops-Werkhoven C Pathmamanoharan OL Gijzeman PH Wiersema 《Canadian Metallurgical Quarterly》1977,471(2):177-188
Interactions between dimyristoyl- and dipalmitoyl phosphatidylcholine vesicles have been studied by light scattering of dilute dispersions (concn less than or equal to 1 mg/ml). It was found that at 50 degrees C, the two types of vesicles exchange lipid molecules, irrespective of the initial radii of the pure vesicles. When the initial radii are different, the process leads eventually to vesicles of intermediate size. The reaction follows second order kinetics. At room temperature no reaction was observed. The phase diagrams for several lipid systems are discussed. 相似文献