6Clinical and Laboratory Standards Institute(CLSI)/National Commit-tee for Clinical Laboratory Standards.Performance standards for anti-microbial susceptibility testing[S].Ninth informational supplement,Wayne,Pennsylvania:NCCLS,2004.
7Peersman G, Laskin R, Davis J, et al. Prolonged operative time correlates with increased infection rate after total knee arthro- plasty [J]. HSS Journal,2006,2(1) :70 - 72.