Effect of morphine versus tramadol on the immune response during the management of patients with chronic cancer pain Research Authors Mostafa G. Mostafa, khaled Morsy. Mohamad Z. Abdel Rahman and Hosam K.Ahmad Research Department Department of Anesthesia, Intensive care and Pain management Research Journal Ain-Shams J Anesthesiology Research Member Mustafa Galal Mustafa Hassan Research Rank 2 Research Year 2012