DRUG-INDUCED UPPER GASTROINTESTINAL SYSTEM BLEEDINGS: AN EVALUATION OF THE PATIENTS HOSPITALIZED FROM UPPER GIS BLEEDING BETWEEN 1987 AND 1991 YEARS - ÜNSAL, Belkıs; ALTINAY, Z. Abidin; KARA, Bülent; KARAOĞLU, A. Önder; YAZICIOĞLU, Nafi; KARACA, Himmet; KOŞAY, Sadun (Turkish Journal of Gastroenterology, 1993)