In Vitro Synergistic Activity of Combinations of Tetrahydroisoquinolines and Treatment Antibiotics against Multidrug-Resistant Salmonella

Figure 2

Isobolograms of combination effects of tetrahydroisoquinolines (THIQs), with treatment antibiotics against multidrug-resistant S. Typhi. (a) Synergistic effect (FICI = 0.078) of THIQ 1 and chloramphenicol (CHL), (b) additive effect (FICI = 0.625) of THIQ 1 and ciprofloxacin (CIP), (c) no interaction (indifference) (FICI = 1.25) of THIQ 5 and chloramphenicol, and (d) antagonistic effect (FICI = 4.25) of THIQ 3 and ciprofloxacin.

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