[Vitamin B12 level in the blood serum of normal subjects and its seasonal variations].
D045728:Corrinoids; D006397:Hematinics; D006801:Humans; D010507:Periodicity; D012621:Seasons; D044967:Serum; D014805:Vitamin B 12 / Q000097:blood*
D045728:Corrinoids; D006397:Hematinics; D014805:Vitamin B 12
PERIODICITY; VITAMIN B 12/blood