title: A charcoal--agar disc to adsorb free steroid in radioimmunoassay.
mesh_terms: D000327:Adsorption; D000362:Agar; D000818:Animals; D002417:Cattle; D002606:Charcoal; D011374:Progesterone / Q000097:blood / Q000302:isolation & purification; D011863:Radioimmunoassay / Q000379:methods*; D012756:Sheep; D013256:Steroids / Q000302:isolation & purification*
chemical_list: D013256:Steroids; D002606:Charcoal; D011374:Progesterone; D000362:Agar