Objective To study the therapeutic effectiveness and associated complications of unrelated allogeneic hematopoietic stem cell transplantation(URD-HSCT)for leukemia.Methods Twenty-one patients with malignant hematological diseases received URD-HSCT.There were 19 cases of peripheral blood hematopoietic stem cell transplantation,one case of bone marrow transplantation,and one case of umbilical cord blood transplantation.There were 8 cases of HLA matched and13 cases of HLA mismatched transplantation.The median ...