tokens: Sustained proliferation of erythroid progenitors could be induced equally well from purified erythroid burst-forming units ( BFU-E ) , from CD34 ( + ) blast cells , and from bone marrow depleted from CD34 ( + ) cells .
folded_tokens: sustained proliferation of erythroid progenitors could be induced equally well from purified erythroid burst-forming units ( bfu-e ) , from cd34 ( + ) blast cells , and from bone marrow depleted from cd34 ( + ) cells .
labels: O O O B-cell_type I-cell_type O O O O O O B-cell_line I-cell_line I-cell_line I-cell_line O B-cell_line O O O B-cell_type I-cell_type I-cell_type I-cell_type I-cell_type I-cell_type O O O B-tissue I-tissue O O B-cell_type I-cell_type I-cell_type I-cell_type I-cell_type O