title: Frequency of plasmid-determined beta-lactamases in 680 consecutively isolated strains of Enterobacteriaceae.
mesh_terms: D004755:Enterobacteriaceae / Q000187:drug effects / Q000235:genetics*; D010403:Penicillin Resistance; D011815:R Factors; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001618:beta-Lactamases