1 . Thor nsberry C,Barr y A L,Jones RN,et al . Co mparison of in vitro activity of sch21420,a genta micin B derivative,wit h those of a mikacin,genta micin,netil micin,siso micin and tobra mycin . Anti microb Agents Chemother。7 . Kobayashi Y,Uchida H,Kawa ......