1WATrS J L,YANCEY R J, SALMON S A, et al. A 4 - year survey of antimicrobial susceptibility trends for isolates from cattle with bovine respiratory disease in North America[ J]. J Clin Microb, 1994, 32:725 - 731.
2SCHMOLKA I V. Artifcial skin I. Preparation and properties of pluronic F -127 gels of treatment of bums [ J ]. J Biomed Mater Res,1972,6(6) :571 -582.
6SOUZA M J, NOGUEIRA D R, SILVA L M, et al. Development and validation of an HPLC method for determination of ceftiofur sodium[ J]. Chem Mater Sci,2007,65:401 -406.
