MezlocillinPiperacillinPenicillinsTicarcillinPenicillanic AcidAzlocillinCarbenicillinMicrobial Sensitivity TestsAnti-Bacterial AgentsAmpicillinEnterobacteriaceaeMeningitis, Listeriabeta-LactamsBacterial InfectionsCephalosporinsBacteriaGentamicinsPseudomonas aeruginosaPenicillinaseAminoglycosidesPenicillin ResistanceHalf-Life