title: Letter: Decreasing frequency of e antigen with age in serum of symptom-free carriers of hepatitis B antigen.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000941:Antigens / Q000302:isolation & purification; D002353:Carrier State; D002648:Child; D002675:Child, Preschool; D006509:Hepatitis B / Q000276:immunology*; D006511:Hepatitis B Antigens / Q000302:isolation & purification; D006515:Hepatitis B virus / Q000472:pathogenicity; D006801:Humans; D007223:Infant; D008875:Middle Aged
chemical_list: D000941:Antigens; D006511:Hepatitis B Antigens