Objective To explore the clinical significance of exposure the recurrent laryngeal nerve（RLN） for preventing the RLN injury in thyroidectomy. Methods The data of 1 723 patients with thyroid diseases undergoing total or subtotal thyroidectomy from September 2006 to August 2011 were retrospectively reviewed. RLN were exposed in 914 cases, 1 203 RLNs were exposed（exposed group）. RLN were unexposed in 809 cases, 1 013 sides were cut（unexposed group）. To compare RLN injury rate after operation and recovery of vocal cord in 6 months after operation between the two groups. Results In exposed group, 11 cases had RLN injury, the rate of RLN lesion was 0.91%. In unexposed group, 21 cases had RLN injury, the rate of RLN lesion was 2.07%. The differences between the two groups had statistical significance（P＜0.05）. When six months after operation, 0 case and 13 cases in exposed group and unexposed group respectively occurred permanent RLN injury, the differences between the two groups had statistical significance（P＜0.01）. Conclusion Exposure of RLN in total and subtotal thyroidectomy can significant avoid RLN injury, especially RLN permanent injury.
Objective To investigate the effects of X-ray dose on the expressions of microRNA-221 （miR-221） and phosphatase and a tensin homolog deleted from chromosome10 （PTEN） in human colorectal carcinoma （CRC） cells. Methods Human CRC-derived cell line， Caco2， was cultured conventionally. The cells were divided into five groups and exposed to different doses of X-ray （0， 2， 4， 6， and 8 Gy） respectively. The total RNA and protein of the Caco2 cells were extracted after irradiation， and the miR-221 and PTEN mRNA expressions were detected by real-time RT-PCR.Moreover， the protein alteration of PTEN in Caco2 cells was detected by Western-blot analysis. Results The radiation dose of X-ray significantly affected the expressions of miR-221 and PTEN protein in human Caco2 cells in a dose-depen-dent manner. Moreover， the miR-221 expression level was up-regulated gradually with the increase of irradiation dose， on the contrary， the PTEN protein expression level was down-regulated gradually （P＜0.01）. Conclusion The radiation dose can affect the miR-221 and PTEN protein expression pattern in CRC cells.