This paper aims at analyzing the reform strategies in the clinical teaching for stomatology undergraduates: strengthening the management of clinical education,the establishment of a capable and effective teaching force,stimulating students’ interest in learning,guide their independent learning,the introduction of case teaching method etc,to promote clinical teaching and improve the teaching quality.

Objective To investigate the feasibility of setting up practical course in community oral health education.Methods In the period of experimental teaching of Preventive Dentistry,the practical courses in community oral health education were offered to114 undergraduates who enrolled in 2003,2004 or 2005.And the teaching effectiveness was evaluated.Results About 70 percent of the students believed that the abilities of oral health education,integrating theory with practice,expressing and interpersonal communication would be trained through this practical teaching.94.74 percent of the students considered that it is necessary to practice course in community oral health education.Conclusion Practicing course in community oral health education will be good for improving the overall quality of undergraduates and promoting oral health education campaign of students'active participation,which has a feasibility.

Purpose To investigate the effect of subcellular location of tumor BRCA1 on the sensitivity to ionizing radiation (IR) and PARP inhibitor.Methods siRNA of BRCA1 were first used to inhibit endougenous BRCA1 expression in MCF7 cells.Then,plasmids of pCMV-3xFlag-WT-BRCA1,pCMV-3xFlag-NES-BRCA1 and pCMV-3xFlag-NLS-BRCA1 were transfected in MCF7 cells.Immunofluorescence staining was used to detect BRCA1 subcellular location as well as the formation of Rad51 and γ-H2AX foci.Apoptotic cells were analyzed by flow cytometry,and colony formation assay was performed to evaluate the survival of cells.Results There were 47％ cells with nuclear BRCA1,23％ cells with cytoplasmic BRCA1 and 30％ cell with mixed nuclear and cytoplasmic BRCA1 expression in WT-BRCA1 transfected cell.There were 87％ cells with nuclear BRCA1 in NES-BRCA1 transfected cell,and 82％ cells with cytoplasmic BRCA1 in NLS-BRCA1 transfected cell.There were 87％,84％ and 13％ Rad51 foci positive cells at 2 hours after 4 Gy radiation treatment and 22％,25％ and 59％ γ-H2AX foci positive cells at 24 hours after 4Gy radiation treatment in WT-BRCA1,NES-BRCA1 mutant and NLS-BRCA1 mutant transfected cell respectively.ABT-888 and radiation treatment induced more apoptosis and fewer colonies in NLS-BRCA1 transfected cell than WT-BRCA1,NES-BRCA1 mutant transfected cell.Conclusion Subcellular location of BRCA1 might affect homologous recombination repair of DNA double strand breaks and can be used to predict sensitivity to IR and PARP inhibitor.

Objective:This study aims to examine the clinicopathological features, diagnosis, and treatment of pulmonary margin-al zone B-cell lymphoma of mucosa-associated lymphoid tissue (PMZL-MALT). Methods:The clinicopathological features and immu-nohistochemical staining of CD20, CD79a, CD5, CD10, CD23, CyclinD1, and Ki-67 in seven patients with PMZL-MALT were ana-lyzed. Results:These patients, with a median age of 58 years, included three males and four females. Most of the patients suffered from cough, anhelation, and irregular fever. No specific imaging manifestation was observed. Tumor cells were positive for CD19 and CD20 but negative for CD5, CD10, and CyclinD1. The positive rate of Ki-67 was low. Conclusion:PMZL-MALT cases are easily misdiag-nosed because of the absence of specific clinical characteristics and X-ray features. Final diagnosis depends on pathological examina-tions.

The mRNA expressions of chemerin and its receptor CMKLR1 in adipose tissue of OLETF rats and LETO rats were detected by real-time PCR. The results showed that the two genes mRNA expressions in subcutaneous and visceral adipose tissue in OLETF group were significantly higher than those in LETO group (P< 0.05 or P<0.01) and expressions of them in visceral adipose tissue were higher than those in subcutaneous adipose tissue(P<0. 05 or P<0. 01), suggesting that chemerin and CMKLR1 may be involved in the pathogenesis of obesity, insulin resistance, and type 2 diabetes mellitus.

ObjectiveTo discuss the relationship between post-traumatic stress disorder(PTSD) and self psychologieal elastic for and to provide the scientific basis early for PTSD and psychological intervention.Methods 592 students were selected with the method of random cluster sampling to be investigated with children self psychological elastic scale and post-traumatic stress disorder and screening of questionnaire.ResultsThere were 45 students were PTSD screening positive group,accounting for 7.60％ of the total number,and 15 male students,accounting for 2.53％ of the total number,there were 30 female students,accounting for 5.07％ of the total number.Male and female in psychological elastic scale score were no significant differences (P＞ 0.05 ),PTSD positive group psychological screening elastic total cent and factors points were significantly lower than negative group(P＜ 0.05),PTSD total score was a significantly negative correlation( r =- 0.454,P =0.000).ConclusionPsychology resilience can be used as predictors of incidence of PTSD.

Objective:To explore the potential of thrombus-targeted nanoprobes for ultrasound/near-infrared bimodal imaging and their synergistic therapeutic effects on thrombosis in vitro.Methods:Nanoprobes loaded with arginine-glycine-aspartate peptide (RGD), perfluoropentane (PFP) and indocyanine green (ICG) were prepared by ultrasonic vibration and carbodiimide method with mesoporous silica nanoparticle (MSN) as the carrier. The probe morphology was observed by scanning and transmission electron microscopy. The loading of RGD and ICG was detected by Bicinchoninic Acid Assay (BCA) and UV-Visible-NIR spectroscopy respectively. The imaging performance and photothermal response of the nanoprobe under near infrared light (NIR) irradiation were studied in vitro. Its biological safety was tested by cytotoxicity test and hemolysis test. The phase transformation was studied under ultrasound and NIR irradiation. The nanoprobe was incubated with fresh arterial thrombus, and its target-seeking ability was observed by frozen section. Ultrasound and NIR irradiation were used to evaluate its thrombolytic ability by the weight changes of thrombus before and after irradiation.Results:The prepared nanoprobe had regular morphology and uniform size. The particle diameter was (156.83±5.05)nm, and the surface potential was (11.47±0.25)mV. The RGD coupling rate was (77.67±4.50)%, which could mediate the targeting of nanoprobe to fresh extracorporeal arterial thrombus. UV-Visible-NIR spectroscopy confirmed the successful loading of ICG, and its encapsulation rate was (80.47±0.05)%. After ultrasound and NIR irradiation, the nanoprobe could undergo acoustically induced phase transition, thermally induced phase transition and enhance the ultrasonic development effect. With the increase of the concentration of the nanoprobe solution, the NIR signal gradually increased, and the temperature rose in a concentration-dependent and intensity-dependent manner after NIR irradiation. The cytotoxicity test and hemolysis test showed that the nanoprobe had good biological safety, and it could play a thrombolytic role under the combined irradiation of ultrasound and NIR, and the weight of thrombus was significantly reduced after the treatment ( P<0.01). Conclusions:In this study, the nanoprobe (RGD/ICG/PFP@MSN) were successfully prepared possesses excellent dual mode imaging capabilities of ultrasound and NIR, excellent phase transition ability and photothermal conversion efficiency, as well as efficient targeted penetration and therapeutic effects against thrombosis. This study provides strong in vitro experimental evidence and new strategies for the integration of diagnosis and treatment of thrombotic diseases under the cooperation of ultrasound and NIR.

Objective:To investigate the application value of stereotactic digital naviga-tion system assisted three-dimensional (3D) laparoscopic total mesorectal excision (TME) for rectal cancer.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of a healthy volunteer recruited by the Second Affiliated Hospital of Army Medical University and 3 patients who underwent stereotactic digital navigation system assisted 3D laparoscopic TME for rectal cancer in the Second Affiliated Hospital of Army Medical University from May to September 2019 were collected. The healthy volunteer was male, aged 25 years. Of the 3 rectal cancer patients, there were 2 males and 1 female, with the age of 48 years, 63 years and 67 years, respectively. Ten special patches were placed at the anterior superior iliac spine, pubic tubercle and pubic symphysis of the volunteer's bilateral inguen as skin reference points in intraoperative localization and system registration. On the day of operation, patients were placed 10 special patches as skin reference points according to the test results of the volunteer and were completed the enhanced scan of totally abdominal computed tomography examination. Seven fixed anatomical markers in the abdominal cavity of the patients, including abdominal aortic bifurcation, sacrum scapula, bilateral anterior superior iliac spine, bilateral intersection of ureter and iliac artery and median point of peritoneal reflection, were selected for verifying the accuracy of the correspondence between the instrument tip and the system image. Patients underwent 3D laparoscopic TME for rectal cancer assisted by stereotactic digital navigation system. Observation indicators: (1) test results; (2) surgical situations; (3) accuracy of stereotactic digital navigation system. Measurement data with normal distribution were represented as Mean± SD. Results:(1) Test results. The 10 skin reference points of the volunteer were successfully registered in the stereotactic digital navigation system, with the registration error of 2.8 mm. (2) Surgical situations. All the 3 patients underwent stereo-tactic digital navigation system assisted 3D laparoscopic TME for rectal cancer successfully. The operation time of the 3 patients were 193 minutes, 175 minutes, 210 minutes, respectively, in which the set time of the stereotactic digital navigation system were 34 minutes, 25 minutes, 45 minutes, respectively. The volume of intraoperative blood loss of the 3 patients were 60 mL, 30 mL, 80 mL, respectively. Results of postoperative pathological examination showed 3 patients with adenocar-cinoma, including 1 case with mucinous adenocarcinoma. The tumor diameter and the numbers of lymph nodes dissected of the 3 patients were 2.3 cm, 1.5 cm, 4.0 cm and 12, 12, 13, respectively. No patient had lymph node metastasis. The 3 patients in preoperative clinical TNM stage cT3bN0M0, stage cT4aN1M0, stage cT3bN1M0 were in yield pathological TNM stage ypT1N0M0, stage ypT4aN0M0, stage ypT2N0M0 after neoaduvant chemotherapy, respectively. No patient had complication, and the duration of postoperative hospital of the 3 patients was 7 days, 6 days, 7 days, respectively. (3) Accuracy of stereotactic digital navigation system. The registration errors of the skin reference points were 2.8 mm, 2.6 mm, 2.9 mm and the accuracy errors of the abdominal cavity reference points were (2.5±0.4)mm, (2.3±0.7)mm, (2.6±0.6)mm for the 3 patients.Conclusion:The stereotactic digital navigation system assisted 3D laparoscopic TME for rectal cancer is safe and feasible.

BACKGROUND: Epidermal growth factor receptor (EGFR) mutation is the most common gene mutation in patients with non-small cell lung cancer (NSCLC). Many international guidelines are recommended to detected the EGFR mutation before the treatment of advanced non-small cell lung cancer. To investigate the possibility of EGFR mutation testing on DNA extracted from fixation liquid of lung cancer biopsy. METHODS: Fixation liquid of lung cancer biopsy was collected and stored at -80 oC after centrifugal. DNA was extracted and EGFR gene mutation was detected by ARMS. Compared with EGFR mutation status of paraffin-embedded tissues, the consistency, the sensitivity and specificity of EGFR mutation testing were analyzed. RESULTS: Among the 28 cases of EGFR mutation positive and 20 cases of EGFR mutation negative previously tested on paraffin-embedded tissue by clinic test, 20 cases with EGFR mutation positive and 20 cases with negative were detected by matched fixation liquid of lung cancer biopsy, respectively. The sensitivity and specificity were 71.4% and 100%. Moreover, 52 paraffin-embedded tissues and matched fixation liquid of lung cancer biopsy with unknown EGFR mutation status were detected, and the EGFR mutation positive rate were 36.5% and 28.8% respectively. The sensitivity and specificity of fixation liquid of lung cancer biopsy were 78.9% and 100.0%. CONCLUSIONS Extracting the DNA from fixation liquid of lung cancer biopsy may be a kind of feasible way to detect EGFR mutation.

BACKGROUND: Epidermal growth factor receptor (EGFR) is the gene with the highest mutation rate in non-small cell lung cancer (NSCLC) patients, and the accurate evaluation of its mutational status can facilitate patients receiving targeted drug therapy and thereby prolong patients' survival. The gene testing platform has adequacy requirements for the specimen quality in order to obtain accurate examination results. It has been reported that the number and proportion of tumor cells in samples will affect the detection rate of EGFR gene mutation. The present study aims to analyze the relationship between the quality of small biopsy specimens of NSCLC and the mutation rate of EGFR gene with amplification refractory mutation system (ARSM) test. METHODS: After collecting the clinical characteristics of 299 cases small biopsy of lung adenocarcinoma, DNA concentration of the specimens and the mutational status of EGFR gene, the number and proportion of tumor cells in HE stained sections evaluated using light microscopy, the relationship between specimen quality and the mutation rate of EGFR gene were analyzed. RESULTS: The mutation rates of EGFR for the groups with tumor cell number ≤500 and >500 were 40.7% (11/27) and 43.8% (119/272) respectively, without significant difference (P=0.764). The mutation rates for the groups with DNA concentration ≤20.4 ng/μL and >20.4 ng/μL were 42.7% (64/150) and 44.3% (66/149) respectively, without significant difference (P=0.776). The mutation rates for the groups with tumor cells proportion ≤30% and >30% were 29.4% (20/68) and 47.6% (110/231) respectively, demonstrating significant difference (P=0.008). Multivariate Logistic analysis showed that male, thyroid transcription factor-1 (TTF-1) negative, smoking history and tumor cell proportion less than 30% were main factors that contributes to the low detection rate of EGFR gene mutation. CONCLUSIONS After meeting the minimum requirements for detection, the EGFR mutation rate is affected by the proportion of tumor cells in the sample. Therefore, it is necessary to re-evaluate the tumor cell proportion in the last section after the genetic test section. For samples with lower tumor cell proportion, enriching tumor cells through microdissection and other methods is recommended for a more accurate detection result. For specimens that cannot be enriched with tumor cells, circulating tumor DNA (ctDNA) test can be performed as a supplement. If the result is still negative, another biopsy should be considered to obtain enough tumor specimens for molecular testing.