During the past few years the determination of the nitrogenous constituents of the blood has been rendered much more simple and accurate by the improved methods of Folin and Denis,1 Marshall and Davis,2 Van Slyke and Cullen,3 Benedict,4 and others. Previous to the studies of Folin and his co-workers very little, if any, dependence could be placed on the quantitative analysis of the blood for its nonprotein nitrogenous constituents.
BLOOD IN ADULTS
The results of many investigations of the chemistry of the blood have recently appeared in the literature, and, as a result, standard figures for adults are now available.5The total nonprotein nitrogen of the blood has been demonstrated to be the index of the efficiency of the kidney in removing waste nitrogenous products circulating in the blood. It has been conclusively shown that the total nonprotein nitrogen is increased in the blood in
LEOPOLD JS, BERNHARD A. THE NONPROTEIN NITROGENOUS CONSTITUENTS OF THE BLOOD AND THE PHENOLSULPHONEPHTHALEIN TEST IN CHILDREN. Am J Dis Child. 1916;XI(6):432–440. doi:10.1001/archpedi.1916.04110120029002