syrian hamsters were treated with either a low ( 10 mg/kg body weight ) or high ( 40 mg/kg body weight ) single dose of bis ( 2-oxopropyl ) nitrosamine ( bop ) and beginning 1 week later fed either low ( 0.2 mmol/kg diet ) or high ( 0.4-1.0 mmol/kg diet ) levels of one of four retinoids [ 13 cis retinoic acid ( 13-cis-ra ) , n-ethylretinamide ( era ) , n- ( 2-hydroxyethyl ) retinamide ( ohera ) or n- ( phenyl ) retinamide ( pra ) ] for periods of 40 or 50 weeks .
C0035339
retinoids
C0022265
13 cis retinoic acid