The clinical practice is a very important link for medical students to relate theory with practice and to be trained comprehensively.Stomatology is an applied science,so clinical practice is more outstanding and important during the stomatological education.This thesis discusses how to improve stomatological students' comprehensive skill in the clinical practice.

Objective　: To verify the feasibility of using a homemade lung phantom for quality control of Cyberknife by comparing the measurement results of the homemade lung phantom and CIRS dynamic phantom in E2E testing of Cyberknife lung tracking.  Methods　 : The patient treatment process was simulated, including CT positioning, plan design, irra- diation implementation, film scanning, and analysis using the homemade phantom and CIRS phantom. The two phantoms were measured five times using MLC under the S7 generation Cyberknife and five times using Iris under the M6 generation Cyberknife. The differences in measurement results between the two phantoms were analyzed using independent sample t-test. Results　: For the S7 generation Cyberknife, the statistical analysis of differences between the two phantoms in the detection values on the X-axis, Y-axis, Z-axis, and total deviation showed P values of 0.236, 0.175, 0.289, and 0.668, respect- ively. For the M6 generation Cyberknife, the statistical analysis showed P values of 0.880, 0.891, 0.573, and 0.433, respect- ively. The P values were all > 0.05. Therefore, there were no statistically significant differences in the detection results between the homemade lung phantom and the CIRS phantom under the S7 and M6 generation Cyberknife. The total deviation values were <1.5 mm. Conclusion　 The homemade lung phantom and CIRS phantom have consistent measurement results in the E2E testing of Cyberknife lung tracking and meet the requirements of Report of AAPM TG-135 and WS 667- 2019 standard. Therefore, the homemade lung phantom is feasible for clinical quality control of Cyberknife.

BACKGROUND:In recent years,the treatment of anterior cruciate ligament injury has become more and more mature.However,there are still disputes about the timing of surgery,the choice of surgical methods,the choice of grafts,and the methods to promote graft healing after anterior cruciate ligament injury. OBJECTIVE:To summarize the latest research progress of surgical timing,surgical methods,graft selection and methods to promote graft healing after anterior cruciate ligament injury,and to find new treatment directions for anterior cruciate ligament injury. METHODS:Relevant articles concerning anterior cruciate ligament injury were retrieved from PubMed,CNKI,WanFang Date,VIP,SinoMed,ScienceDirect,Springer and Cochrane Library.After the screening,72 related articles were finally included. RESULTS AND CONCLUSION:(1)Surgical timing:Compared with delayed anterior cruciate ligament reconstruction,early reconstruction can reduce meniscus injury,elevate quality of life,and improve functional recovery.However,it is still uncertain whether the different operation timing will accelerate cartilage injury.(2)Surgical methods:Arthroscopic anterior cruciate ligament reconstruction is a common surgical method for anterior cruciate ligament injury.Dynamic internal stabilization repair of anterior cruciate ligament can bring similar results to traditional anterior cruciate ligament reconstruction in short-term and long-term effects.(3)Graft selection:Autogenous hamstring tendon is the first choice of anterior cruciate ligament graft,while bone-patellar tendon-bone grafts and allografts are the secondary choices.(4)Among the methods to promote graft healing,suture band strengthening can increase knee joint stability and ensure graft healing.Stem cells promote the tendon-bone healing of grafts through anti-inflammatory action,angiogenesis,inhibition of osteolysis and promotion of chondrocyte differentiation.Preserving the residual end of the anterior cruciate ligament can maintain the stability of the knee joint,promote the recovery of proprioception,and provide a prerequisite for the healing of the graft.The effectiveness of platelet-rich plasma in promoting graft healing remains to be discussed.However,biomaterials,gene therapy,stem cell application and other methods to promote tendon healing remain in the stage of molecular and animal researches.Clinical transformation is also needed in the future.

Objective:To investigate the effect of mitochondrial division of GABAergic neurons in substantia nigra pars reticulata(SNr)on motor dysfunction in mice with acute hepatic encephalopathy(AHE).Methods:AHE mice model was established by intraperitoneal injection of thioacetamide(TAA).The changes of liver lobules in AHE mice were observed by hematoxylin-eosin(HE)staining.The changes of serum aspartate aminotransferase(AST),alanine aminotransferase(ALT)and blood ammonia in AHE mice were detected by biochemical detection kit.Then,the motor function of AHE mice was observed by rod fatigue test,elevated cross maze test and open field test.Furthermore,the changes of mitochondrial area,perimeter,roundness and other morphological indicators in SNr of AHE mice were ob-served and analyzed by transmission electron microscopy.The expression of mitochondrial division and fusion related molecules in SNr of AHE mice was observed by Western Blot.Then,the expression of mitochondrial dynamic related protein 1(DRP1)in SNr of AHE mice was targeted by AAV virus.The mitochondrial membrane potential(MMP),ATP and reactive oxygen species(ROS)in SNr were detected by fluorescence enzyme marker,and the changes of motor function of mice were observed.Results:Compared with the control group,the motor function of AHE mice was signifi-cantly decreased,the mitochondrial division of SNr was significantly enhanced,and the expression of mitochondrial divi-sion related proteins was significantly increased.The MMP in SNr of AHE mice was significantly decreased,the ATP of cells was decreased,and the ROS was increased.After targeted inhibition of DRP1 expression in SNr of AHE mice,the movement was improved;further observation found that after the mitochondrial division in SNr of AHE mice was inhibi-ted,the MMP was significantly increased,the ATP of cells was increased,and the ROS was decreased,which demon-strated that the mitochondrial function was significantly improved.Conclusion:Targeted inhibition of mitochondrial di-vision of GABAergic neurons in SNr of AHE mice can improve mitochondrial morphology and function,thus alleviating their movement disorders.

ObjectiveTo observe the clinical effect of Yiqi Liangxue Shengji Formula （益气凉血生肌方， YLSF） on recurrence of angina pectoris and quality of life at eight weeks after perecutaneous coronary intervention （PCI）. MethodsEighty-two coronary artery disease （CAD） patients with qi deficiency and blood stasis and binding of stasis and heat syndrome who had underwent PCI were randomly divided into two groups with 41 patients each in the treatment group and the control group. Based on conventional western medicine after PCI， patients in the treatment group orally took YLSF granules while those in the control group were administered with placebo， one dose daily for 8 weeks. The recurrence rate of angina pectoris and readmission rate within eight weeks after PCI were recorded. Before and after treatment， total traditional Chinese medicine （TCM） syndrome score， Seattle Angina Questionnaire （SAQ） scores （physical limitation， angina stability， angina frequency， treatment satisfaction and disease perception）， and the SF-36 scores for quality of life （physical and mental health） were evaluated. The adverse reactions during medication in both groups were recorded. ResultsWithin eight weeks after PCI， the recurrence rate of angina pectoris in the treatment group （4/41， 9.76%） was significantly lower than that in the control group （11/41， 26.83%， P＜0.05）. The readmission rate in the treatment group was 2.44% （1/41）， while that in the control group was 12.20% （5/41）， with no significantly statistical difference （P＞0.05）. After treatment， total TCM syndrome score significantly decreased in both groups， while in terms of quality of life， the SAQ scores on domains of angina stability， angina frequency and disease perception as well as SF-36 total scores， physical health and mental health scores significantly increased （P＜0.05 or P＜0.01）. Compared between the two groups， total TCM syndrome score was significantly lower in the treatment group than the control group （P＜0.01）， while no significant differences were found in SAQ scores and SF-36 total， physical and mental health scores （P＞0.05）. No adverse reactions occurred in both groups during the treatment period. ConclusionYLSF can reduce the recurrence rate of angina pectoris within eight weeks after PCI for coronary artery disease， and can improve the TCM syndrome score， and have sound safety， with comparable effect to that of placebo in improving postoperative short-term quality of life.

Objective: To discuss the feasibility of applying home-made auto quality assurance (AQA) phantom in Cyberknife AQA test. Methods: The same treatment plan for AQA test was designed in the Cyberknife treatment planning system. The AQA tests were performed under the same conditions using the home-made AQA phantom and the AQA phantom in the fourth-generation (G4) Cyberknife mode and the fifth-generation (VSI) Cyberknife mode, respectively, and each measurement was repeated five times to analyze and compare the differences in test results between the two phantoms. Results: The total deviations of the home-made AQA phantom and the AQA phantom in the AQA test under the G4 Cy- berknife mode were (0.28 ± 0.12) mm and (0.28 ± 0.15) mm, respectively (P > 0.05); the test results under the VSI Cy- berknife mode were (0.46 ± 0.19) mm and (0.50 ± 0.07) mm, respectively (P > 0.05); the total deviations of all test results were smaller than 1.0 mm, which met the requirements of WS 667—2019 Specification for Testing of Quality Control in Ro- botic Arm Radiotherapy Device. Conclusion The test results of the home-made AQA phantom and the AQA phantom are consistent in the AQA test, and the home-made AQA phantom can be used for Cyberknife quality control.

Objective To explore the feasibility of quartz glass for radiotherapy dosimetry through the experimental study of the thermoluminescence characteristics of synthetic quartz glass. Methods The thermoluminescence glow curves of quartz glass under different annealing conditions were analyzed, the thermoluminescence characteristics of quartz glass were studied, and the measurement parameters were optimized. Using the Co-60 reference radiation field in the National Secondary Standard Dosimetry Laboratory, the quartz glass samples under different annealing conditions were irradiated following the dose levels of radiotherapy, i.e., 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 Gy, respectively. According to the relationship between the absorbed dose of quartz glass and the relative thermoluminescence signal intensity, the linearity and dispersion of the dose response of quartz glass were obtained, and the feasibility of quartz glass for radiotherapy dosimetry was analyzed. Results The linear correlation coefficient of dose response of quartz glass under annealing condition of 430℃ for 10 min was 0.9984, and the dose response dispersion was 0.97% at the absorbed dose of 2 Gy. The linear correlation coefficient of dose response of quartz glass under annealing condition of 600℃ for 1 h was 0.9911, and the dose response dispersion was 1.4% at the absorbed dose of 2 Gy. Conclusion Preliminary results suggest that quartz glass with annealing condition of 430℃ for 10 min has the potential to be used for radiotherapy dosimetry.

Objective: To explore the changes in root volume and root resorption in incisor arteries from adult patients with skeletal class Ⅲ malocclusion before and after camouflaged orthodontic treatment and to provide a reference for the clinic. Methods : Thirty permanent dentition adult patients with skeletal class Ⅲ malocclusion were included from the Orthodontic Department. CBCT data of each patient at pretreatment and posttreatment were acquired, and 3D digital root models were reconstructed. The whole and segmented root volumes (cervical part, bodily part and apical part) of the right incisors were calculated. Results: The root volumes (whole, cervical part, bodily part and apical part) posttreatment were smaller than those pretreatment (P<0.001). Maxillary central incisors and lateral incisors showed similar resorption in the cervical root and bodily root and more changes in the apical root, but there was no significant difference (P>0.05). Mandibular central incisors and lateral incisors showed more root resorption in the apical root than in the cervical root and bodily root (P<0.01). The absorption ratio of all segmented roots in each incisor showed a significant difference (P<0.001), and apical absorption was the most obvious. There were no significant differences in root volume change amounts or the absorption ratio of the whole, cervical part and bodily part in all incisors (P>0.05). The absorption ratio showed a significant difference in the mandibular lateral incisors (P = 0.028). Conclusion After camouflaged orthodontic treatment of adult skeletal class Ⅲ malocclusion, incisor root resorption occurred mainly in the apical part, but the cervical and bodily parts should also be considered. There was a high risk of root resorption in the mandibular incisors.