Objective:To analyze and compare the dose monitoring and control systems of two types of medical linear accelerator systematically from the view of mechanical and electrical engineering, and establish the method of the quality assurance of the dosimetry system and the solution in the routine maintenance.Methods: To systematically compare and analyze the system of dose monitoring and control for two types of linear accelerators (Precise Elekta and C-series of Varian Medical Systems) from twofold aspects that included machine physics and electric engineering of medical linear accelerators.Results:The monitoring system that took ionization chamber as center was established between connotation of machine physics and concrete realization of electromechanical engineering, and explained the difference and similarity between open type and sealed type of ionization chamber, and the theory that Precise series needn't be serviced by PFN.Conclusion: Based on the analysis of ionization chambers structure of medical linear accelerators on the principle of quality assurance system, proposed dosimetric testing and adjustment method, and provide reference for the establishment of quality assurance system and technical procedures of the maintenance engineering.

Objective To investigate the therapeutic effect of Qingre-Jiedu formula combined with negative pressure drainage for hand trauma infection. Methods A total of 108 patients with hand trauma infection were randomly divided into 2 groups, 54 cases in each group. The observation group were given Qingre-Jiedu formula combined with vacuum sealing drainage treatment, and the control group only received the treatment of vacuum sealing drainage. After 14 days' treatment, the score of wound secretion and granulation tissue were recorded, and ELISA method was used to detect IL-6, TNF-α detected by immune measure method, and the wound healing and healing time were recorded after treatment. Results After treatment, the secretion score (1.6 ± 0.4 vs.2.2 ± 0.4,t=4.659), granulation tissue score (1.7 ± 0.2 vs.2.2 ± 0.3, t=4.541) in the observation group were significantly lower than those in the control group (P<0.01); the serum IL-6 (64.89 ± 2.31 μg/L vs.72.18 ±3.02 μg/L,t=9.562),TNF-α(318.67 ±15.21 μg/L vs.397.49 ±17.63 μg/L,t=15.611)were significantly lower than those in the control group (P<0.01). The wound healing rate of the observation group was 96.3% (52/54), and control group was 55.6% (30/54), where there was significant difference between two groups (χ 2=24.518,P<0.01); the wound healing time in observation group (15.2 ± 3.0 d vs.25.2 ± 4.7 d, t=11.551) was significantly shorter than that in the control group (P<0.01). Conclusions The Qingre-Jiedu formula combined with negative pressure drainage for hand trauma infection could promote wound healing, improve healing effect and reduce the level of inflammatory reaction..