Influence of N-Ras* on EPO-dependent development.

(A) Cumulative expansion of GFP⁺, CD13⁻ cells during the EPO-dependent phase of growth. (B) Frequency of gly A expression; insets show representative data at day 13 (open histograms show nonspecific fluorescence). (C) Cell size (forward scatter); insets show representative data at day 17. In each case, error bars represent SD (from at least 4 experiments); *P < .05, **P < .01.