Objective To investigate the incidence and risk factors of neck and back pain in pilots, aviation cadets and me-chanical maintenance personnel, with an aim to prevent the occurrence of the disorder among them.Methods A survey of 2001 cases of medical data was conducted, and then, the derived data concerning neck and back pain were compared and analyzed between pilots, aviation cadets and mechanical maintenance personnel.Results The incidence of neck and back pain in aviation cadets was 19.3%, and the incidence rates of the same disorder in pilots and mechanical maintenance personnel were 43.0%and 31.9%respectively.The incidence of neck and back pain in the aviation cadets flying fighters was 29%, and the incidence rates of the same disorder in the avia-tion cadets flying transports and helicopters were 44.1%and 37.4% respectively.Risk factors of neck and back pain among aviation cadets included age, flying time, smoking history, body mass index and lumbodorsal muscular exercise.Conclusion The incidence of neck and back pain in pilots was significantly higher than that in aviation cadets and mechanical maintenance personnel, and the inci-dence of the disorder was also relatively high in pilots flying transports.Flying time was the most important risk factor of neck and back pain, and the survey revealed that lumbodorsal muscular exercise was an effective protective factor.Close attention should be paid to the prevention of neck and back pain and counter measures should be developed for effective prevention of the disorder.

Objective To investigate the efficacy and safety of multi-band mucosectomy (MBM) for the treatment of high-grade intraepithelial neoplasia.Methods The clinical data of 24 patients with high-grade esophageal intraepithelial neoplasia who were admitted to the Henan Honliv Hospital from April 2011 to October 2012 were retrospectively analyzed.All the 24 patients received MBM,and the operation time,resection of the lesion and complications were observed.All the patients were followed up with gastroscopy at postoperative 1,3,6,12 months.The follow-up was ended in April 2013.Results A total of 26 lesions in 24 patients were resected successfully by MBM (2 patients received MBM twice).The mean operation time was 42 minutes.The mean length of the lesions was 3.1 cm (range,0.8-6.0 cm),and it occupied 3/4 of the circumference of the esophagus to the maximum.The mean number of the band used was 4 (range,1-6).During the operation,bleeding was occurred in 4 patients,and they were cured by hot biopsy forceps.No perforation of the esophagus was detected.The results of post-MBM pathological examination showed that 22 patients were with severe atypical hyperplasia,and 2 were with carcinoma in situ.During the follow-up of 6-24 months,22 patients were cured,and esophageal stricture occurred in 1 patient at post-MBM 1 month,and the symptoms were successfully relieved by endoscopic balloon dilatation.Neoplasia recurrence was observed in 1 patient (2 lesions were resected twice) at post-MBM 3 months,and he received surgical treatment.Histopathological diagnosis showed that he had esophageal squamous cell carcinoma.No stricture or neoplasia was detected by gastroscopy at postoperative month 12.Conclusions MBM is a relatively safe and effective endoscopic technique for the treatment of high-grade esophageal intraepithelial neoplasia.The resection range should not be blindly extended.For patients whose lesions are beyond 3/4 of the circumference of the esophagus in width or with multiple lesions which can not be resected by MBM at one time,MBM should be applied cautiously to avoid esophageal stricture and recurrence.