title: Lack of dihydrofolate reductase activity in brain tissue of mammalian species: possible implications.
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D002417:Cattle; D006168:Guinea Pigs; D006801:Humans; D007583:Jejunum / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008297:Male; D051379:Mice; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013056:Spectrophotometry, Ultraviolet; D013154:Spleen / Q000201:enzymology; D013762:Tetrahydrofolate Dehydrogenase / Q000032:analysis*
chemical_list: D013762:Tetrahydrofolate Dehydrogenase