Fig. 6. Summary of the change in SSC frequency resulting from addition of various retinoid derivatives. Bar graph represents mean increase in SSC frequency induced by a series of retinoid derivatives; the name for each is indicated below the bars. Each bar shows the mean (±s.e.m.) compared to control from 7-9 cell cultures. For comparison, the horizontal dashed line defining basal activity as 1 is shown. ^*P<0.05 compared to the RA treatment group (Student's t-test).