CD34 and myelodysplastic syndrome: In this study, we analyzed for the first time the cell cycle distribution of different compartments of BM hematopoietic cells –e.g.: CD34+ hematopoietic progenitor and precursor cells, maturing neutrophils and monocytic cells, mature lymphocytes, eosinophils and nucleated red blood cell precursors (NRBC)- in a relatively large cohort of 230 BM samples including 106 MDS patients, 30 AML and 94 normal/reactive BM samples.