Objective To observe the clinical effect of a silicone tractor in the treatment of nipple inversion. Methods 15 patients were treated with this new type of tractor. Of all the patients, 11 were with mild to moderate nipple inversion, and 4 were serious affected patients. In the seriously affected group, the tractor was used after operation. Patients in the mild to moderate nipple inversion group was treated with the silicone tractor only. Results The result in all the patients was satisfactory after follow-ing-up for 6 to 12 months. The appearance of the nipples was well. Conclusion Continuously pulling with silicone tractor is an ideal method in nipple inversion treatment. It is simple, safe and effective.

Objective:To explore teaching methods to improve the teaching effect in view of many difficulties in learning medical statistics for clinical medical students.Methods:Taking the clinical medical students of the same grade as the research objects, the students were randomly divided into two groups by cluster sampling in class, i.e. control group and experimental group. The traditional teaching methods and the scenario-based interactive learning software teaching methods were used respectively. The scores of medical statistics courses examinations and the statistical errors in responding to projects of extracurricular research activities were compared between the two groups. SPSS 19.0 was performed for statistical analysis.Results:The results of subject achievements of the students in the experimental group (74.08±11.19) were higher than those in the control group (63.82±10.10) ( t=3.926, P<0.001), especially the comprehensive capabilities of the innovative analysis questions and the multiple-choice questions. The statistical errors of the students in the experimental group was less than those in the control group. There were significant differences between the two groups in the estimation of sample size ( χ2=4.189, P=0.041), statistical design ( χ2=5.558, P=0.018) and data analysis ( χ2=3.971, P=0.046). Conclusion:The results suggest that scenario-based interactive learning software is helpful to improve teaching efficiency, and enhance students' ability to analyze and solve practical problems by using medical statistics knowledge.