title: Observations on the radiopacity of stone substances with special reference to cystine.
mesh_terms: D015502:Absorptiometry, Photon; D001031:Apatites; D002118:Calcium; D002130:Calcium Phosphates; D003553:Cystine; D006801:Humans; D010070:Oxalates; D055585:Physical Phenomena; D010825:Physics; D014527:Uric Acid; D014545:Urinary Calculi / Q000000981:diagnostic imaging*; D014867:Water
chemical_list: D001031:Apatites; D002130:Calcium Phosphates; D010070:Oxalates; D014867:Water; D014527:Uric Acid; D003553:Cystine; D002118:Calcium