Medical-technical marathon.
D001782:Blood Donors; D006509:Hepatitis B / Q000175:diagnosis / Q000517:prevention & control*; D006511:Hepatitis B Antigens; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D008403:Mass Screening; D014481:United States
D006511:Hepatitis B Antigens