title: Sputum viscosity and long-term ipratropium bromide nebuliser therapy.
mesh_terms: D000402:Airway Obstruction / Q000188:drug therapy; D001286:Atropine Derivatives / Q000009:adverse effects*; D006801:Humans; D009241:Ipratropium / Q000009:adverse effects*; D012138:Respiratory Therapy; D013183:Sputum / Q000187:drug effects*; D013997:Time Factors; D014783:Viscosity
chemical_list: D001286:Atropine Derivatives; D009241:Ipratropium