2Nelson EC, Elisha BG. Molecular basis of AmpC hyperproduction in clinical isolates of Escherichia coli [J]. Antimicrob A-gents Chemother , 1999,43 957.
3Corvec S,Caroff N,Espaze E, et al. - 11 mutation in the ampC promoter increasing resistance to beta-Lactams in a Clinical Escherichia coli Strain[J] . Antimicrob Agents Chemother , 2002,46:3265.
4Coudron PE, Moland ES,Thomson KS. Occurrence and detection of AmpC β- lactamases among Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis isolates at a Veterans' Medical Center[J] . J Clin Microbiol,2000 ,38 :1791.
5Dubus A, Normarck S, Kania M, et al. The role of tyrosine 150 in catalysis of β- lactam hydrolysis by ,AmpC β-lactamase from Escherichia coli investigated by site-directed mutagenesis[J]. Biochemistry, 1994,33 : 8577.
6Bauernfeind A, Wagner S, J ungwirth R, et al. A novel class C β-lactamase (FOX- 2) in Esckerickia coli conferring resistance to cephamycins [J] . Antimicrob Agents Chemother,1997,41:2041.
7Bou G,Oliver A,Ojeda M, et al. Molecular characterization of FOX- 4, a new AmpC - type plasmid - mediated β- lactamase from an Escherichia coli strain isolated in Spain[J]. Antirnicrob Agents Chernother , 2000,44 : 2549.
8Stapleton PD,Shannon KP, French GL.Carbapenem resistance in Escherichia coli associated with plasmid - determined CMY - 4 β-lactamase production and loss of an outer membrane protein[J]. Antimicrob Agents Chemother , 1999,43:1206.
9Doi Y, Shibata N, Shibayama K, et al .Characterization of a novel plasmid - mediated cephalosporinase ( CMY-9) and its genetic environment in an Escherichia coli clinical isolate [J].Antimicrob Agents Chemother , 2002,46 : 2427.
10Cloeckaert A, Baucheron S, Flaujac G, et al. Plasmid- mediated florfenicol resistance encoded by the floR gene in Escherichia coli isolated from cattle [J] . Antimicrob Agents Chemother, 2000,44 : 2858.
