ABSTRACT
Objective To provide the scientific foundation for the rational antibiotic therapy.Methods The wild type (10 strains)and hyper-inducible type(5 strains)of trial strains,which were chosen in the First Affiliated Hospital of China Medical University from June 2003 to June 2004,were screened by ceftazidime,and then AmpC ?-lactamase activity was detected.Three dimensional test was used to detect phenotype mutation ,and the mutation rate was calculated.Results None of AmpC ?-lactamase activity was detected in the wild type of Serratia marcescans、Cloaca Enterobacter and hyper-inducible type Serratia marcescans.For the hyper-inducible type Cloaca Enterobacter,there was marked difference compared with the AmpC ?-lactamase activity induced by the 2 MIC ceftazidime for that of MIC and 1/2 MIC(P