부산대학교 도서관

In Reply.—We agree with Dr Axelrod regarding our choice of terminology and feel that the ascorbic acid effect could be more accurately described as "preventing the alkalinization of urine rather than by producing an acid urine." Upon review of Dr Axelrod's letter, there are several comments that we would like to make.The statement that the inhibition of bacterial urease is "undoubtedly" the cause of the change is somewhat overstated, since, as noted by Dr Axelrod, the effect of ascorbic acid on the pH of voided urine can be influenced by a number of factors, including the number of urease-producing bacteria, the concentration of urea, the concentration of ascorbic acid, the incubation time of the urine in the bladder and collecting system, and the presence of cysteine and copper in the urine.The inhibition of urease activity presented in the Table represents in vitro data. It would be informative