Vitamin B 12 in the serum and the cerebrospinal fluid.
D001284:Atrophy; D001927:Brain Diseases / Q000097:blood / Q000134:cerebrospinal fluid; D006801:Humans; D009103:Multiple Sclerosis / Q000097:blood / Q000134:cerebrospinal fluid; D013118:Spinal Cord Diseases / Q000097:blood / Q000134:cerebrospinal fluid; D014805:Vitamin B 12 / Q000097:blood* / Q000134:cerebrospinal fluid*
D014805:Vitamin B 12