Figure 2 - Effect of treatment with silica on the clearance of E. coli B41 (A) and India ink (B). E. coli B41 or India ink suspension was injected into the tail vein of conventional (circles) or silica-treated conventional (squares) mice and blood samples were taken from the retro-orbital plexus at the time of injection and 15, 30, 60 and 90 min after injection and treated as described in Material and Methods. The results are reported as percent viable cells per ml blood determined as described in the legend to Figure 1 (A) or as absorbance (l = 650 nm) (B) in relation to time 0. Each point is the mean for 5 mice of one representative experiment of two performed. Vertical bars indicate standard deviation of the means. *P£0.05, **P£0.01 compared to conventional mice (Student t-test).