Fig. 1From: Absence of in vivo mutagenicity of multi-walled carbon nanotubes in single intratracheal instillation study using F344 gpt delta rats Pig-a mutant frequencies. Four weeks after the treatments, blood was withdrawn and analyzed by flow cytometry for the presence of surface CD59 on RBCs. Each treated group is shown under the bars. The data are the mean ± standard deviation (SD). **p < 0.01 compared to the controlBack to article page