The effects of synthetic 19-norprogestins on osteoblastic cell function are mediated by their non-phenolic reduced metabolites. - Enriquez,J.; Lemus,AE.; Chimal-Monroy,J.; Arzate,H.; Garcia,AG.; Herrero,B.; Larrea,F.; Perez-Palacios,G. (J Endocrinol, 2007)