(A) Mean linear relationship between the natural log of the number of CD34⁺ cells injected (in millions) and the logit-transformed percentage of human cells in the BM (n = 63); and (B) mean estimated relationship (in 50 animals) between the number of CD34⁺ cells and CD34⁻ cells injected (linear scale, horizontal axes) and the logit-transformed percentage of human cells in the BM (vertical axis). Data are based on a generalized additive statistical model calculated by the SAS statistical package. Both (A) and (B) only included animals that were not treated with growth factors. In (B), not every combination of CD34⁺and CD34⁻ cells was available for analysis. The areas outside the data range are indicated by zero engraftment in the far-left and front-right corners of the graph. The graph was plotted using the S-Plus (Mathsoft) statistics package.