the ki values of 50 % inhibition of dna topoisomerases from calf thymus by ciprofloxacin , norfloxacin , novobiocin , nalidixic acid , and ofloxacin were 300 , 400 , 1,000 or more , 1,000 or more , and 1,500 or more micrograms/ml , respectively , in the case of topoisomerase i , and the ki values were 150 , 300 , 500 , 1,000 , and 1,300 micrograms/ml , respectively , in the case of topoisomerase ii .
C0949775
dna
C0012863
topoisomerase ii