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991.
The Reflomat System for rapid estimation of plasma or blood glucose concentration has been evaluated. The System gave a linear response throughout its analytical range and the recovery of glucose added to glucose-free plasma was 97-105%. Addition of sodium fluoride to plasma produced a 7-15% reduction in the estimated glucose concentration. Plasma glucose concentration estimated with the Reflomat agreed closely with results of a glucose oxidase and a hexokinase based method, and blood glucose concentration measured with the Reflomat agreed well with results of a glucose oxidase method. 相似文献
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993.
The first component of complement, C1, was isolated unactivated from human serum by repeated additions of di-isopropyl phosphorofluoridate during isolation. The unactivated subcomponents were also isolated, and evidence is given that the three subcomponents C1q, C1r and C1s account wholly for the activity of component C1 in serum. No evidence could be found for a fourth subcomponent, C1t. The approximate molar proportions of the subcomponents in serum are C1q/C1r/C1s = 1:2:2. Optimum activity by haemolytic assay was found at approximate molar proportions C1q/C1r/C1s of 1:4:4. No activity was found when subcomponents were assayed singly or in pairs, except for subcomponents C1q and C1s, which in molar ratio 1:4 gave 15-20% of the activity of the mixture C1q + C1r + C1s. The proteolytic activity of the isolated subcomponent C1s varied according to the method of activation used. Subcomponents C1q + C1r + C1s and C1q + C1s in the presence of antibody-antigen aggregates were activated and inactivated simultaneously, showing a peak of activity and subsequent loss of activity. Both reactions are probably due to proteolysis, and analysis of the peptide bonds split will be necessary to distinguish these two phenomena. 相似文献
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998.
Acute complete heart block in dogs 总被引:1,自引:0,他引:1
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