| isolation and characterization of escherichia coli o157:h7 from retail meats in argentina. | between february and may 2000, 279 meat samples were collected from 136 retail stores in gualeguaychú city, argentina. samples were assayed for escherichia coli o157:h7 by selective enrichment in modified ec broth containing novobiocin, followed by immunomagnetic separation (ims) and plating onto both sorbitol macconkey agar supplemented with cefixime and potassium tellurite and a chromogenic medium. eleven e. coli o157:h7 isolates were detected in 6 (3.8%) of 160 ground beef samples, in 4 (4.8% ... | 2001 | 11563511 |