- O(6)-benzylguanine
- O6-benzylguanine
- obatoclax
- obatoclax mesylate
- obese
- obesity
- objective improvement
- objective response
- oblimersen sodium
- observation
- observational study
- obsessive-compulsive disorder
- obstruction
- obtundation
- occult primary tumor
- occult stage non-small cell lung cancer
- occupational therapist
- OCT
- octreotide
- octreotide acetate
- octreotide pamoate
- octreotide scan
- ocular melanoma
- odanacatib
- odds ratio
- odor
- odorant
- Oestrogenine
- Oestromenin
- Oestromon
- ofatumumab
- off-label
- Office for Human Research Protections
- ofloxacin
- OGF
- oglufanide disodium
- OGX-011
- OHRP
- ointment
- olanzapine
- olaparib
- olfaction
- olfactory
- olfactory system
- olfactory transduction
- oligoastrocytoma
- oligodendrocyte
- oligodendroglial tumor
- oligodendroglioma
- oligofructose-enriched inulin