Human RAR alpha expression was unchanged in H9 and CEM cells , and elevated in U937 cells , after PMA stimulation .
human rar alpha expression was unchanged in h9 and cem cells , and elevated in u937 cells , after pma stimulation .
O O O O O O O B-cell_line O B-cell_line I-cell_line O O O O B-cell_line I-cell_line O O B-other_organic_compound O O