3Lindgren P K,Karlsson A,Hughes D. Mutation rate and evolution of fluoroquinolone resistance in Escherichia coli isolates from patients with urinary tract infections[J].{H}Antimicrobial Agents and Chemotherapy,2003,(10):3222-3232.
4Akiba T,Koyama K,Ishiki Y. On the mechanism of the development of multiple-drug-resistant clones of Shigella[J].{H}Japanese Journal of Microbiology,1960.219-227.
5Zhang C P,Ning Y,Zhang Z Q. In vitro antimicrobial susceptibility of streptococcussuis strains isolated from clinically health sows in China[J].{H}Veterinary Microbiology,2008,(3/4):286-392.