[Antimicrobial susceptibility and beta-lactamase productivity of recent clinical isolates during the period between December 1999 and February 2000].

Antimicrobial susceptibility testings of 24 antimicrobial agents against 605 clinical strains belonging to 10 species were carried out according to the micro-broth dilution method of NCCLS M7-A4. The productivity of beta-lactamase was also determined against them isolated at 8 medical facilities in Nagano prefecture, Japan during the period between December 1999 and February 2000. When applied the nitrocefin method, beta-lactamase productivity was demonstrated to be positive for 89.