title: The emergence of drug resistance in tumours: a characteristic which may be exploited therapeutically.
mesh_terms: D000619:Aminohydrolases; D000818:Animals; D003561:Cytarabine / Q000627:therapeutic use; D003562:Cytidine; D004247:DNA / Q000096:biosynthesis; D004351:Drug Resistance; D006801:Humans; D007938:Leukemia / Q000201:enzymology; D007939:Leukemia L1210 / Q000188:drug therapy; D008727:Methotrexate / Q000627:therapeutic use; D009369:Neoplasms / Q000188:drug therapy* / Q000201:enzymology
chemical_list: D003561:Cytarabine; D003562:Cytidine; D004247:DNA; D000619:Aminohydrolases; D008727:Methotrexate