Profil enzim o6-methylguanine-dna methyltransferase (MGMT) dan karakteristik pasien glioma di departemen bedah saraf RSUPN Cipto Mangunkusumo Jakarta = O6 methylguanine dna methyltransferase (MGMT) profile and characteristic of gliomas patients in neurosurgery department of Cipto Mangunkusumo Hospital Jakarta