腹股沟疝和痔一样是人类独有的疾病，这是因为人是直立的缘故，当然，猩猩是否也有此问题尚未见报道。在胚胎发育和解剖上，腹股沟有薄弱之处是重要因素，老年人腹股沟部筋膜、肌肉弱化也是重要因素，许多论著和医生经验均有论述。
To verify the role of mAbCD28 in allograft transplantation. The biological action of mAbCD28 had been tested in mixed-lymphocyte-reaction and parathyroid gland allotranplantation in rats. Results: mAbCD28 could significantly suppress the proliferation of T cells in vitro and prolong the survival time of allograft in vivo. The results showed that mAbCD28 could block the costimulatory signals transmitted by CD28 molecules, and played an immunosuppressive role in parathyroid gland transplantation in rats.