Clinical Efficacy of Azathioprine (AZA) for Treatment of Mild to Moderate Ulcerative Colitis (UC) in Patients Who Have Responded Inadequately to Steroids. - Juliao B., Fabián; Agudelo Z., Yineth; Yepes D., Carlos; Bejarano, Luis I.; Thorrens, Jose G.; Fabián, Jaimes B. (Revista Colombiana de Gastroenterología, 2015)