Over 500 nurses of the All India Institute of Medical Sciences (AIIMS) here went on strike on Sunday over the death of a nurse during treatment at the hospital, officials said.According to a senior official, a nurse named Rajveer Kaur, who was being treated at the AIIMS, died on Saturday.The nurses have alleged negligence in treatment by the doctor and are demanding suspension of the doctor who was treating Kaur. AIIMS has about 5,000 nurses and they are considered as the backbone of the hospital.