title: On the progestational activity of the 20-ethylene ketals of 21-fluoropregnan-20-ones.
mesh_terms: D000818:Animals; D002625:Chemistry, Organic; D010064:Embryo Implantation / Q000187:drug effects*; D005260:Female; D055601:Organic Chemistry Phenomena; D011372:Progestins / Q000494:pharmacology*; D011817:Rabbits; D013256:Steroids / Q000494:pharmacology*
chemical_list: D011372:Progestins; D013256:Steroids