Task: Translation
Input (Czech): Podstatou °e en  je zji t n ,  e amid hydromastn  kyseliny v kombinaci s retinolem nebo retinylov²m esterem p sob  synergickou inhibici diferenciace keratinocyt . Kosmetick  · inky retinolu nebo retinylov²ch ester  v kombinaci s amidy hydroxymastn²ch kyselin byly analogick  s p soben m kyseliny retinov .\
Output (English): It is found that hydromastic acid amide in combination with retinol or retinyl ester is synergistic in inhibiting keratinocyte differentiation. Retinol or retinyl ester cosmetics in combination with hydroxy fatty acid amides were analogous to those of retinoic acid.