tokens: Long term culture of TPA -differentiated U-937 cells in the absence of phorbol ester for 32-36 days resulted in a process of retrodifferentiation .
folded_tokens: long term culture of tpa -differentiated u-937 cells in the absence of phorbol ester for 32-36 days resulted in a process of retrodifferentiation .
labels: O O O O B-other_organic_compound O O O O O O O B-other_organic_compound I-other_organic_compound O O O O O O O O B-other_name O