_:vb50951637 . _:vb50951637 "A brain glioma that has_material_basis_in oligodendrocytes."^^ . _:vb50951637 . _:vb50951637 . _:vb50951637 . _:vb50951637 . _:vb50951637 . _:vb50951637 "url:http://www.cancer.gov/dictionary?CdrID=46257"^^ .