RESUMEN
BACKGROUND:The traditional repair methods for laryngeal cartilage defect are restricted by donor source, rejection, which are difficult to be popularized. OBJECTIVE:To investigate the effect of polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold in repair of laryngeal cartilage defect. METHODS: A total of 20 Wistar rats were randomly divided into polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold and polylactic acid-glycolic acid copolymer scaffold groups. Polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold and polylactic acid-glycolic acid copolymer scaffold were respectively used for repair after the establishment of laryngeal cartilage defect models. RESULTS AND CONCLUSION: The laryngeal cartilage defect diameter of rats at 3, 5 and 7 days after modeling in the polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold group was significantly smaler than that in the polylactic acid-glycolic acid copolymer scaffold group. The laryngeal cartilage defect of rats in the polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold group was basicaly repaired and presented with a smooth surface, and there were no clear boundaries with surrounding tissues; however, the laryngeal cartilage defect of rats in the polylactic acid-glycolic acid copolymer scaffold group had indentations with a rough surface, and there were obvious boundaries with surrounding tissues. These results demonstrate that polylactic acid-glycolic acid copolymer/hydroxyapatite composite scaffold can promote the repair of laryngeal cartilage defect part, and its repair effect is more ideal.
RESUMEN
Objective To investigate the advantages of DR images produced by tissue equalization(TE)technique in chest digital radiography(DR) compared with standard technique.Methods 100 images collected from DR chest images taken in our hospital in May,2003 were processed by TE technique and compare with standard DR images.Results The details in different thickness area of body could be revealed clearly in the same image produced by TE technique,while the display parameters should be adjusted repeatedly to reveal the details in standard chest digital radiography.Conclusion The visualization of image details can be obviously improved by using the TE technique and other details are not lossed.