title: Fast atom bombardment and tandem mass spectrometry of covalently modified nucleosides and nucleotides: adducts of pyrrolizidine alkaloid metabolites.
mesh_terms: D013058:Mass Spectrometry; D009705:Nucleosides / Q000032:analysis; D009711:Nucleotides / Q000032:analysis; D011763:Pyrrolizidine Alkaloids / Q000032:analysis*
chemical_list: D009705:Nucleosides; D009711:Nucleotides; D011763:Pyrrolizidine Alkaloids