twelve antimicrobial agents , ampicillin , aztreonam , cefamandole , cefazolin , cefonicid , ceforanide , ceftazidime , ceftizoxime , ceftriaxone , cefuroxime , ciprofloxacin , and norfloxacin , were prepared at ph 6.80 and 7.31 in microdilution trays for storage at 4 , -10 , -25 , and -70 degrees c and for weekly susceptibility testing .
C1136254
antimicrobial agents
C0028365
norfloxacin