but were resistant to ampicillin , carbenicillin , cefonicid , cefoperazone , ceftriaxone , cephalexin , cephapirin , chloramphenicol , clindamycin , gentamicin , nitrofurantoin , oxacillin , piperacillin , tetracycline , tobramycin , trimethoprim-sulfamethoxazole , vancomycin , and cephalothin .
C0002680
ampicillin
C0031955
piperacillin