Hepatitis B carriage and Brucella seroprevalence in urban and rural areas of Bolu province of Turkey: A prospective epidemiologic study - KARABAY, Oğuz; SERİN, Erdinç and TAMER, Ali and GÖKDOĞAN, Feray and ALPTEKER, Hacer and ÖZCAN, Arzu and GÜNDÜZ, Hüseyin (Turkish Journal of Gastroenterology, 2004)