the in vitro activities of the new ureidopenicillins piperacillin , mezlocillin , azlocillin , and bay k 4999 were compared with those of ampicillin and ticarcillin against 336 enterobacteriaceae , 109 nonfermenters , 55 neisseria , and 28 haemophilus influenzae isolates .
C0031955
piperacillin
C0002680
ampicillin