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A) Histogram of number of animals divided by treatment groups and number of tumors found per animal in the prevention of lung tumor initiation protocol. *P < 0.05; **P < 0.005; ***P < 0.001; n.s. = non-significant. Poisson regression was used for analysis of number of tumors. B) Boxplot of the log (tumor size, mm2) by treatment group. A mixed effects model was used for analysis of tumor size. Horizontal line in box of boxplot represents the median. + represents the mean.
