title: Frequency of sickle cell crises cut by hydroxyurea use.
mesh_terms: D000755:Anemia, Sickle Cell / Q000188:drug therapy*; D018849:Controlled Clinical Trials as Topic; D006801:Humans; D006918:Hydroxyurea / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D006918:Hydroxyurea