  In this paper we use a continuous model to describe the development of a
single cell lineage following the committal of stem cells. Three separate
controls are implemented in the model, namely the proliferative control of stem
cells, the proliferative control of developing blast cells, and the peripheral
control of stem cell committal by circulating blood cell density. We show that
variation of parameters in all three control systems can cause oscillations,
and that the characters of these oscillations are very different. This allows
us some potential insight into the mechanisms that may be operative in some of
the dynamic blood diseases like cyclical neutropenia and periodic chronic
myelogenous leukemia.
