title: Selective malabsorption of vitamin B12: report of a case and studies on vitamin B12 absorption.
mesh_terms: D000748:Anemia, Macrocytic / Q000209:etiology; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007408:Intestinal Absorption; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D014805:Vitamin B 12 / Q000378:metabolism*
chemical_list: D014805:Vitamin B 12