title: In vitro estimation of tracheal mucous velocity: comparison of a solid and a liquid marker.
mesh_terms: D000818:Animals; D004285:Dogs; D066298:In Vitro Techniques; D008751:Methylene Blue; D009093:Mucus / Q000502:physiology*; D011138:Polytetrafluoroethylene; D012212:Rheology / Q000295:instrumentation*; D014132:Trachea / Q000502:physiology
chemical_list: D011138:Polytetrafluoroethylene; D008751:Methylene Blue