This trial aims to investigate whether stem cells from the patient's own bone marrow can improve neurological function in diabetic neuropathy. The trial is being conducted by Central Hospital of Wuhan; Tongji Medical College, and Huazhong University of Science and Technology and seeks to enrol 100 patients. Participants will be randomly divided into either a group that only receives conventional treatment for diabetes (control group), and another groups that will receive an infusion of stem cells obtained from the patient's own bone marrow. Participants will be monitored for complications and changes in clinical condition. The trial is scheduled to run from October 2010 to December 2013.