Objective: To study the relationship between the depth and width of cavity design and to analyze the tendency of breaking load in preparations. Methods:Plaster models of mandibular first molar were prepared and magnified by 150%. Cavity on occlusal surface was designed and prepared in a cylinder shape with the depth(mm) of 3.0,4.5 and 6.0,and diameter(mm) of 3.0,4.5 and 6.0,respectively. 8 cavity samples were prepared for each design. The breaking load of the tooth models before and after restoration with self-curing resin was measured by Instron tester.Mechanical model static load test and two variable regression analysis were applied to study the mechanical property of the cavity design. Results:Before restoration, with the increase of depth and diameter, the incidence rate of tooth fracture increased. The width was the main factor. After restoration, the load was undertaken by restoration directly, and could be transfered to tooth and periodontal tissue through restoration uniformly. When the diameter of the cavity increased, the diameter of restoration also increased, and thus decreased the load on local structure of the tooth. With two-regression analysis, the regression equation and regression curve were obtained. Conclusion: The fracture of tooth before and after restoration is related to the diameter and depth of cavity design in cylinder shape. The regression equations of changing tendency of breaking load (Y) in preparation caused by the change of depth(X 1) and diameter(X 2) of cavity obtained by two-regression analysis are presented as follows: Before restoration: Y=1593.317-51.178 X 1-79.489X 2.After restoration:Y=1802.928 -192.461X 1+225.128X 2.

Objective To study the diagnosis and treatment results of the traumatic perforation of the esophagus.Methods Retrospective analysis was performed in 19 cases with the traumatic perforation of the esophagus hospitalized.Results Treatment options ranged from aggressive to conservative management.Repair of esophageal perforation was performed in 9 cases,cervical drainage in 2 cases and conservative treatment in 8 cases.17 cases recovered from the disease,making up 89.5%the mortality rate was 10.5%.Conclusion In order to increase the recovery rate and decrease the mortality.it is important to diagnose and treat the disease in it's early phases.

Objective: To compare efficacies and complications of total hip arthroplasty ( THA ) with subtrochanteric osteotomy for treating patients with Hartofilakidis types C1 and C2 developmental dyspla-sia of the hip ( DDH) .Methods:Retrospective analysis was performed in 32 patients with DDH who un-derwent THA.These patients were divided into two groups according to Hartofilakidis classification, 17 patients in type C1 and 15 in type C2.Their HSS and WOMAC scores, leg length discrepancy (LLD), hip joint image data and complications were evaluated.Results:HSS scores in type C1 was changed from preoperative 43.7 ±4.6 to postoperative 87.2 ±7.1 (P<0.001), together with WOMAC scores 43.6 ± 4.3 to 87.5 ±6.7 (P<0.001).HSS scores in type C2 was changed from preoperative 44.4 ±5.4 to postoperative 86.5 ±8.0 (P<0.001), together with WOMAC scores 44.1 ±4.1 to 86.7 ±8.1 (P<0.001).Four cases in type C2 and one case in type C1 presented intraoperative fracture which all healed during the postoperative follow-up.The postoperative X-ray films showed that the joint prosthesis location was satisfactory, the surrounding bone was not dissolved and the bone at femur osteotomy site healed with no infection.Conclusion:For unilateral high dislocation DDH patients, THA with femur osteotomy can be effective and safe.No significant differences were found between types C1 and C2, however intraoper-ative fracture in type C2 should be paid attention to.

Objective To investigate the effect of transplantation of allogeneic bone marrow hematopoietic cells(HCs)and mesenchymal stem cells(MSCs)on experimental colitis(EC)in rats.Methods The HCs and MSCs obtained from SD male rats were cultured and expanded in vitro.In experiment 1 and 2 groups,HCs were labeled with bromodeoxyuridine(BrdU)and MSCs were obtained using the tube wall attach technique,respectively.Seventy-two female rats were infused with trinitrobenzene sulfonic acid(TNBS)to induce EC models.After 24 hours,HC or MSC suspensions were injected into the rats in experimental 1(n=18)and 2(n=18)groups via caudal veins,respectively.Control animals were injected with isotonic saline.The whole colon was removed on day 7,14 and 21 after transplantation and examined histopathologically.BrdU labeled HCs were tested with immunohistochemical staining and MSCs were detected for sex-determining gene(sry)by PCR.Results EC models were successfully established.The HCs or MSCs grew rapidly in the culture suspension.On day 7,14 and 21 after transplantation,the BrdU immunoreactive cells were detected in the colon(6/6),and the positive expression of the sry gene was found in 1/6,2/6 and 3/6,respectively.No positive labeled cell was found in controls.There was no significant improvement in histopathological scores on the colon in two experimental groups compared with the controls.Conclusions Allogeneic HCs and MSCs may localize in the colon of EC models.The ability of localization is higher in HCs than MSCs.The transplantation of HCs and MSCs can not obviously improve histopathologically.

Objective:To evaluate the clinical efficacy and prognostic factors in patients with stage Ⅲb/c or Ⅳ inoperable advanced gastric cancer.Methods:The clinical data of 33 patients with unresectable locally advanced (stage Ⅲb/c) or unresectable stage Ⅳ gastric cancer were collected from May 2017 to may 2019 in the Department of Surgical Oncology, Anqing Hospital affiliated to Anhui Medical University, Among them, there were 25 males and 8 females with an average age of 65.48±9.00 years. According to the data of patients with conversion therapy efficacy and postoperative pathology and other factors for statistics, using univariate and multivariate analysis method to evaluate its correlation with the prognosis of patients.Results:Of 33 patients, 2 patients were complete remission, 18 patients were partial remission, the objective response rate(ORR) was 60.6%. 20 patients recevied surgical treatment, 17 patients achieved R0 resection. The median overall survival(mOS) of all 33 patients was (18.6±4.5) months. The mOS of patients who underwent surgical treatment was (25.7±10.99) months, which in patients without surgical treatment was (11.2±2.5) months( P=0.004). The mOS of stage Ⅲb/c patients Was (18.9±10.99) months, and of stage Ⅳ patients was (11.3±0.35) months( P=0.568). Univariate analysis showed that preoperative chemotherapy cycle ≥4 weeks had a better prognosis than patients with less than 4 cycles ( P=0.003), TRG score 1/2 patients had a better prognosis ( P=0.001), and positive lymph nodes ≥7 was risk factor. Multivariate analysis showed that positive lymph nodes ≥7 was the only independent prognostic factor ( P=0.013). Conclusion:For patients with stage Ⅲb/c or Ⅳ inoperable advanced gastric cancer, surgical resection after conversion therapy can improve patient survival, adequate preoperative chemotherapy can improve the prognosis of patients with at least 4 cycles of chemotherapy.

Objective To understand the current status of disinfection and sterilization of medical institutions at all levels in 30 counties in Chongqing ,and to guide the work that medical institutions regulate and improve the quality of disinfection and steriliza‐tion ,and urge the relevant departments to strengthen the monitoring of disinfection quality of medical institutions .Methods Using field investigation and sampling inspection method ,the disinfection quality of medical institutions at all levels in 30 counties of Chongqing city was monitored and analyzed .Results From 30 districts and counties ,the medical institutions were sampled from 28 510 parts ,the overall average pass rate of 93 .3% .The qualified rate of medical institutions at all levels from high to low were as follows ,the village health room (96 .7% ) ,urban community medical institutions (96 .6% ) ,district level medical institutions (96 .1% ) ,individual clinic (90 .9% ) ,private hospitals (93 .7% ) and township (street) medical institutions (86 .5% ) .Different types of medical institutions got different qualified rate ,and the difference was statistically significant(χ2 =666 .84 ,P<0 .01) .Pro‐ject with the lowest qualified rate was radiation intensity of ultraviolet lamp(52 .8% ) ,secondly was indoor air (80 .4% ) and differ‐ent projects′qualified rate was significantly different(χ2 =1 706 .81 ,P<0 .01) .Conclusion Medical and health institutions at all levels′s disinfection quality were generally good ,but the village health room monitoring coverage ,ultraviolet light intensity and oth‐er individual monitoring projects need to be improved .

Objective To explore the effect and mechanism of preventing ankle instability through exer-cise, so as to provide evidence-based references for practice. Methods The randomized and controlled trials ( RCT) on preventing ankle instability through exercise published before December 2014 were searched for in the NCBI, CNKI, VIP and Wanfang databases by computer, supplemented by manual searching. Each study′s quality was evaluated according to the standards of the Cochrane handbook by 3 researchers. The outcome indexes were ex-tracted and analyzed using RevMan 5.2 software. Results After the initial selection, 665 papers (357 in English and 308 in Chinese) were retained. From these 92 were chosen after reading the titles and abstracts. Ultimately, 14 RCT studies ( 12 in English and 2 in Chinese) met the inclusion criteria. They showed that exercise improved ankle function and symptoms of ankle instability significantly [SMD=0.98, 95%CI (0.65,1.31), P≤0.01], improved muscle strength [SMD=1.50, 95%CI (0.99,2.01), P≤0.01], improved balance and postural stability [SMD=-0.54, 95%CI (-0.84,-0.25) ,P≤0.01] , but did not improve proprioception or neuromuscular functioning sig-nificantly. Conclusions Exercise can effectively improve muscle strength, balance and postural stability, but not proprioception or neuromuscular functioning. The details of these findings may be related to the exercise intervention chosen.

Objective To investigate hand hygiene(HH) status among health care workers(HCWs) in municipal hospitals in Chongqing City, and provide the basis for making effective HH management strategies.Methods In April-June 2016, HH status among 111 HCWs in 24 municipal hospitals of this city were investigated through questionnaire survey, on-site observation, and hand surface sampling.Results All surveyed departments are installed special hand washing facilities, all surveyed HCWs were performed HH through hand-washing by running water.The proportion of HCWs' hand-washing by disinfectant was higher than six-step hand washing (73.87% [n=82] vs 37.84%[n=42], χ2=29.23, P<0.01);the implementation rate of HH before touching patient was higher than that after touching patients (99.10%[n=110] vs 89.19%[n=99], χ2=9.88, P<0.01).During the process of diagnosis and treatment activities, the maximal total number of bacteria on the surface of hand before and after HH were 475 CFU/cm2 and 85 CFU/cm2 respectively, hand surface colony count after HH was higher than before HH(P<0.01).Age, gender, department, and occupation are important factors influencing HH.The total number of bacteria on hand surface of nurses was higher than non-nurse HCWs, the total number of bacteria on hand surface of female, nurses, and HCWs in class I environment were all higher than male, non-nurse HCWs and HCWs in other types of environment, there were significant difference among the groups (all P<0.05).Qualified rates of HH of each group improved after hand washing, the total number of bacterial colony on hands of HCWs all decreased.Conclusion Hand washing facilities and HH efficacy are good in Chongqing municipal hospitals, however,HH compliance needs to be improved among HCWs aged≥35 years,male HCWs, HCWs in class III and IV environmental departments, as well as non-nurse HCWs.

Objective To introduce the application of the network training on clinicians'knowledge of malaria diagnosis and treatment in Yunnan Province,and evaluate its effect. Methods Through the platform Yiboshi(www.yiboshi.com),the medi-cal and health personnel at the units of provincial,prefectural,county levels and 25 townships of 25 border counties were trained on the knowledge of malaria diagnosis,treatment,prevention and control,and the effects were evaluated by examina-tions,questionnaires and interviews. Results Totally 7152 participants were trained,the average participation,completion and pass rates of the training were 95.26%,98.55% and 97.30%,respectively. The trainees mainly learned malaria control knowledge from 3 aspects,namely policy of malaria elimination,malaria epidemiology,malaria diagnosis and treatment. The questionnaires showed that 95.94%of the participants considered that their theoretical and technical levels improved,97.30%were interested in the training content,93.24% recognized the arrangement of the training time was reasonable,and 91.89%were satisfied with the service of the platform. Conclusions The network training on knowledge of malaria diagnosis and treat-ment in Yunnan Province has achieved good effect. The network training meets the need of training a large number of clinicians in the malaria elimination and post-elimination stage.