to determine whether low concentrations of aminoglycosides in combination with penicillin could effectively kill enterococci in vitro , we tested penicillin ( 20 micrograms/ml ) in combination with decreasing concentrations of either streptomycin ( 20 , 10 , 5 , and 1 micrograms/ml ) or gentamicin ( 5 , 3 , 1 , and 0.5 micrograms/ml ) against 13 strains of streptomycin-susceptible and 7 strains of streptomycin-resistant enterococci isolated from patients with infective endocarditis .
C0038425
streptomycin
C0014121
infective