tokens: ( 2 ) Erythroid 32D Epo1 cells showed a lower level of bulk PKC catalytic activity , lacked the expression of epsilon and eta PKC isoforms , and showed a weak or absent upregulation of the remaining isoforms , except betaI , upon readdition of Epo to growth factor starved cells .
folded_tokens: ( 2 ) erythroid 32d epo1 cell show a lower level of bulk pkc catalytic activity , lack the expression of epsilon and eta pkc isoform , and show a weak or absent upregulation of the remain isoform , except betaus , upon readdition of epo to growth factor starve cell .