1.Finite element analysis of three internal fixation modalities for treatment of Pauwels type Ⅲ femoral neck fractures under different loading conditions
Zhenggang LI ; Xuehong SHANG ; Zhang WU ; Hong LI ; Chaojun SUN ; Huadong CHEN ; Zhe SUN ; Yi YANG
Chinese Journal of Tissue Engineering Research 2025;29(3):455-463
BACKGROUND:There is still no consensus on the optimal internal fixation for the treatment of Pauwels Ⅲ femoral neck fracture,and most of the related finite element analyses have been performed using a single simplified loading condition,and the biomechanical properties of commonly used internal fixation devices need to be further investigated. OBJECTIVE:To analyze the biomechanical characteristics of Pauwels Ⅲ femoral neck fractures treated with cannulated compression screw,dynamic hip screw,and femoral neck system by finite element method under different loading conditions of single-leg standing loads and sideways fall loads. METHODS:The DICOM data of healthy adult femur were obtained by CT scanning,imported into Mimics 15.0 software to obtain the rough model of bone tissue.The data exported from Mimics were optimized by Geomagics software,and then three internal fixation models were built and assembled with the femur model according to the parameters of the clinical application of the cannulated compression screw,dynamic hip screw,and femoral neck system by using Pro/E software.Finally,the three internal fixation models were imported into Ansys software for loading and calculation to analyze the stress distribution and displacement of the femur and the internal fixation under different working conditions of single-leg standing loads and sideways fall loads,as well as the stress characteristics of the calcar femorale and Ward's triangle. RESULTS AND CONCLUSION:(1)Under the single-leg standing load and the sideways fall load,the proximal femoral stress of the three internal fixation models was mainly distributed above the fracture end of the femoral neck.The peak stress of the proximal femoral end,fracture end,Ward triangle,and calcar femorale of the three internal fixation models were the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(2)Under the single-leg standing load and the sideways fall load,the peak displacement of the proximal femur of the three internal fixation models was all located at the top of the femoral head,and the peak displacement was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(3)The peak displacement of the three internal fixation models was all located at the top of the internal fixation device under the single-leg standing and sideways fall loading conditions,and the peak displacement values were the smallest in the femoral neck system internal fixation model and the largest in the cannulated compression screw internal fixation model.(4)The internal fixation stress of the three internal fixation models was mainly distributed in the area near the fracture end of the internal fixation device under the single-leg standing and sideways fall loads,and the peak value of internal fixation stress was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(5)These results suggest that the mechanical stability of the femoral neck system is the best,but there may be a risk of stress shielding of the fracture end and calcar femorale.The stress of the internal fixation device of the femoral neck system is more dispersed,and the risk of internal fixation break is lower.
2.Analysis of the current status and regulatory effectiveness of daylighting and artificial lighting in primary and secondary school classrooms in Shanghai
YANG Jianping,LIN Jianhai,LI Ping,ZHENG Chaojun,WANG Yaning,LIU Jiajia,MAO Jie
Chinese Journal of School Health 2024;45(6):780-783
Objective:
To understand the current situation and regulatory effectiveness of daylighting and artificial lighting in primary and secondary school classrooms in Shanghai, so as to provide a basis for enhancing the visual environment of school classrooms.
Methods:
From April 2021 to December 2023, the daylighting and artificial lighting conditions of classrooms in 1 735 regular primary and secondary schools currently in operation in Shanghai were monitored, and the qualified rate of each indicator was calculated. The Chisquare test or Fisher exact probability method were used to compare the differences in qualification rates across different educational stages, regions, school type, both before and after the implementation of regulatory measures. The regulatory measures included convene interview, propaganda and education, supervision order, supervisory opinion paper, rectification requests and offenses and punishment.
Results:
The qualified rate of daylighting and artificial lighting in primary and secondary school classrooms was 30.1%, with a qualified daylighting rate of 85.6% and a qualified artificial lighting rate of 32.9%. There was no statistically significant differences in the qualified rate of daylighting and artificial lighting in primary and secondary schools (32.4%,28.1%;χ2=3.76,P>0.05). However, statistically significant differences were found in the qualified rate of daylighting and artificial lighting in urban and rural school classrooms (32.6%,26.7%), as well as in public and private schools (31.4%, 20.6%) (χ2=6.99,9.92,P<0.05). Following the implementation of regulatory measures, the qualified rate of classroom daylighting and artificial lighting improved from 30.1% to 83.2%, while the respective qualified rates of daylighting and artificial lighting increased from 85.6% to 91.1% and 32.9% to 90.5%. Compared to the preimplementation period, the qualified rate of classroom daylighting and artificial lighting, as well as the respective rates of daylighting and artificial lighting, all showed statistically significant differences after the implementation of regulatory measures (χ2=995.29,25.34,1 219.87,P<0.01).
Conclusions
Effective regulatory measures can promote enhanced classroom daylighting and artificial lighting. Attention should be paid to improving classroom artificial lighting, in order to provide students with enhanced visual environment.
3.Lipocalin-2-Mediated Insufficient Oligodendrocyte Progenitor Cell Remyelination for White Matter Injury After Subarachnoid Hemorrhage via SCL22A17 Receptor/Early Growth Response Protein 1 Signaling.
Qiang LI ; Xufang RU ; Yang YANG ; Hengli ZHAO ; Jie QU ; Weixiang CHEN ; Pengyu PAN ; Huaizhen RUAN ; Chaojun LI ; Yujie CHEN ; Hua FENG
Neuroscience Bulletin 2022;38(12):1457-1475
Insufficient remyelination due to impaired oligodendrocyte precursor cell (OPC) differentiation and maturation is strongly associated with irreversible white matter injury (WMI) and neurological deficits. We analyzed whole transcriptome expression to elucidate the potential role and underlying mechanism of action of lipocalin-2 (LCN2) in OPC differentiation and WMI and identified the receptor SCL22A17 and downstream transcription factor early growth response protein 1 (EGR1) as the key signals contributing to LCN2-mediated insufficient OPC remyelination. In LCN-knockdown and OPC EGR1 conditional-knockout mice, we discovered enhanced OPC differentiation in developing and injured white matter (WM); consistent with this, the specific inactivation of LCN2/SCl22A17/EGR1 signaling promoted remyelination and neurological recovery in both atypical, acute WMI due to subarachnoid hemorrhage and typical, chronic WMI due to multiple sclerosis. This potentially represents a novel strategy to enhance differentiation and remyelination in patients with white matter injury.
Mice
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Animals
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Remyelination/physiology*
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Oligodendrocyte Precursor Cells/metabolism*
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White Matter
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Subarachnoid Hemorrhage/metabolism*
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Lipocalin-2/metabolism*
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Early Growth Response Protein 1/metabolism*
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Oligodendroglia/metabolism*
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Mice, Knockout
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Cell Differentiation/physiology*
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Brain Injuries/metabolism*
4.Performance of limiting-antigen avidity enzyme immunoassay and pooling PCR in detection of recent HIV-1 infection among men who have sex with men in Yunnan province
Xiaomei JIN ; Huichao CHEN ; Pengyan SUN ; Zhijun ZENG ; Li YANG ; Chaojun YANG ; Lijun SONG ; Zuyang ZHANG ; Yanling MA ; Min CHEN
Chinese Journal of Epidemiology 2021;42(4):706-710
Objective:To assess and compare the performance of limiting-antigen avidity enzyme immunoassay (LAg-Avidity EIA) and pooling PCR in the surveillance for recent infection rates of HIV-1 in men who have sex with men (MSM).Methods:Blood samples were collected from MSM selected through snowball sampling method in sentinel surveillance in 13 prefectures of Yunnan province from 2016 to 2017. The samples were tested for HIV-1 antibody. The confirmed positive samples were tested by LAg-Avidity EIA. The negative samples were tested by pooling PCR. The recent infection rates of HIV-1 were estimated by the algorithm based on LAg-Avidity EIA and pooling PCR respectively. The two results were compared.Results:During 2016-2017, a total of 5 363 blood samples were collected from MSM, in which 407 samples were HIV-1 positive (including 177 positive tested previously) and 4 956 samples were HIV-1 negative. A total of 211 samples(91.7%) were tested by LAg-Avidity EIA, 69 were confirmed to be recent infections. A total of 4 469 samples were tested by pooling PCR, 8 were confirmed to be acute infections. The recent infection rates of HIV-1 from 2016 to 2017 estimated by LAg-Avidity EIA were 3.36% and 4.84%, and the recent infection rates estimated by pooling PCR were 3.27% and 3.02% respectively. The differences in recent infection rates of HIV-1 estimated by the two algorithms were not significant.Conclusions:The recent infection rates of HIV-1 estimated by LAg-Avidity EIA and pooling PCR in sentinel surveillance in MSM in Yunnan had good consistency from 2016 to 2017. Using the two methods might have a better stability in continuous surveillance for recent infection rates of HIV-1.
5.Sensitivity and specificity of nucleic acid testing in close contacts of COVID-19 cases in Guangzhou
Wenting ZHANG ; Dan LIU ; Chaojun XIE ; Dong SHEN ; Zongqiu CHEN ; Zhihao LI ; Yuan LIU ; Xiru ZHANG ; Peiliang CHEN ; Wenfang ZHONG ; Pei YANG ; Qingmei HUANG ; Lei LUO ; Chen MAO
Chinese Journal of Epidemiology 2021;42(8):1347-1352
Objective:To analyze the sensitivity and specificity of SARS-CoV-2 nucleic acid testing in 20 348 close contacts of COVID-19 cases in different prevention and control stages in Guangzhou and to provide scientific evidence for optimizing epidemic response strategies.Methods:A total of 20 348 close contacts of COVID-19 cases in Guangzhou were traced between February 21 and September 22,2020. All the close contacts were tested for the nucleic acid of SARS-CoV-2. The sensitivity and specificity of nucleic acid testing and diagnosis in the different prevention and control stages were compared.Results:In 20 348 close contacts, 12 462 were males (61.24%), the median ( P 25, P 75) of age of them was 31.0 years (23.0,43.0), the median number ( P 25, P 75) of nucleic acid testing for them was 2.0 (1.0,3.0), and the median ( P 25, P 75) of their quarantine days was 12.0 (8.0,13.0) days, respectively. A total of 256 COVID-19 cases were confirmed in the close contacts after seven nucleic acid tests. In the 1 st, 2 nd, 3 rd and 7 th nucleic acid testing, the sensitivity and specificity were 69.14% and 99.99% (177 cases confirmed), 89.84% and 99.99% (230 cases confirmed), 97.27% and 99.99% (249 cases confirmed), and 100.00% and 99.98%, respectively. In the three stages of COVID-19 prevention and control in China: domestic case stage, imported case stage, and imported case associated local epidemic stage, the sensitivity of the 1 st nucleic acid testing was 70.68%, 68.00% and 67.35%, and the specificity was 99.98%, 100.00% and 100.00%, respectively. Conclusions:The sensitivity of nucleic acid testing in the close contacts at the different stages were consistent with slight decrease, which might be related to the increased proportion of asymptomatic infections in the late stage of epidemic prevention and control with COVID-19 in Guangzhou. It is suggested to give three nucleic acid tests to improve the sensitivity and reduce false negative risk.
6.Efficacy and Safety of Ticagrelor Versus Clopidogrel in the Treatment of ACS Patients in East Asia :A Meta- analysis
Di LIU ; Hui WU ; Jun YANG ; Jian YANG ; Jiawang DING ; Zhixing FAN ; Chaojun YANG
China Pharmacy 2020;31(10):1260-1265
OBJECTIVE:To syst ematically evaluate the effectiveness and safety of ticagrelor versus clopidogrel in the treatment of acute coronary syndrome (ACS)patients in East Asia ,and to provide evidence-based references for clinical drug use. METHODS:Retrieved from Cochrane Library ,PubMed,Embase,CNKI,Wanfang database ,etc.,randomized controlled trials (RCTs)about ticagrelor (trial group )versus clopidogrel (control group )in the treatment of ACS patients in east Asia were collected. After literature screening and data extraction ,the quality of included literatures was evaluated by using biasrisk evaluation tool recommended by Co chrane system evaluation manual 5.1.0,and Meta-analysis was performed by using Rev Man 5.3 statistical software. RESULTS :A total of 5 RCTs were included ,with a total of 4 511 cases. Meta-analysis showed that the incidence of major adverse cardiovascular events [OR =0.85,95%CI(0.68,1.04),P=0.12],the incidence of death from cardiovascular causes [OR =0.76,95%CI(0.57,1.03),P=0.08] and the incidence of stroke [OR =0.77,95%CI(0.48,1.24),P=0.28], without statistical significance. The incidence of major bleeding events [OR =1.54,95%CI(1.19,1.99),P=0.001] and minor bleeding events [OR =1.80,95% CI(1.40,2.32),P<0.000 01] in trial group were significantly higher than control group. CONCLUSIONS:Ticagrelor is comparable to clopidogrel in reduce the major adverse cardiovascular events,death from cardiovascular causes and stroke in ACS patients in East Asian ,but it can increase the risk of major and minor bleeding events.
7.Characteristics of HIV-1 genotype and drug resistance among men who have sex with men in Kunming, 2018
Jie DAI ; Pengyan SUN ; Huichao CHEN ; Lijuan DONG ; Xiaomei JIN ; Youfang LI ; Jue WANG ; Chaojun YANG ; Min YANG ; Zhijun ZENG ; Yanling MA ; Min CHEN
Chinese Journal of Epidemiology 2020;41(8):1335-1340
Objective:To understand the characteristics of HIV-1 genotypes and drug resistance among men who have sex with men in Kunming in 2018.Methods:A total of 193 plasma samples were collected from the newly reported HIV-1 infected MSM in Kunming from January to December 2018. Viral RNA was extracted, and the gag, pol, env gene segments were amplified by nested PCR. HIV-1 genotypes and drug resistance were also analyzed. Subsequently, the evolutionary characteristics of CRF55_01B and CRF68_01B among MSM in Kunming were analyzed by Bayesian Markov Chain Monte Carlo method. Results:Multiple HIV-1 genotypes were identified among these 193 samples, including CRF07_BC (39.4%, 76/193), CRF01_AE (34.2%, 66/193), unique recombinant forms (URFs) (20.2%, 39/193), CRF08_BC (3.1%, 6/193), CRF55_01B (1.6%, 3/193), subtype B (1.0%, 2/193) and CRF68_01B (0.5%, 1/193). Results from the Bayesian evolutionary analysis showed that CRF55_01B started to spread locally after being imported from other provinces, while CRF68_01B was likely to have been brought in from the eastern provinces of China. Prevalence of HIV-1 drug resistant strains was 2.6%(5/190) before antiviral treatment, with mutation rates resistant to non-nucleoside reverse transcriptase inhibitors being the highest (2.1%, 4/190) among MSM in Kunming, 2018.Conclusion:The diversity of HIV-1 was increasing among MSM in Kunming. Although the resistance rate on pretreatment drug was relatively low, the emergence of multiple resistant strains to first-line antiviral drugs posed a challenge to antiretroviral therapy, in Kunming.
8.Endovascular treatment of iliac femoral artery occlusive disease with TASC C, D lesions in elderly patients
Lei TIAN ; Xiguang LIU ; Zhonghua WANG ; Yufeng GU ; Xiaodong YANG ; Shihua WANG ; Chaojun ZHANG
Chinese Journal of Interventional Imaging and Therapy 2017;14(7):400-403
Objective To investigate the effect of endovascular treatment in iliac femoral artery occlusive disease of TransAtlantic Inter-Society Consensus (TASC) C,D lesions in elderly patients.Methods Totally 104 elderly TASC C,D patients with iliac femoral artery occlusion were treated,including TASC C (n =73),TASC D (n =31).Occlusive length range were 4.25-17.61 cm,with an average of (13.46±1.24)cm.The curative effect,complications and following up after surgery were analyzed.Results Ninty-four patients were treated successfully,and the technical success rate was 90.38% (94/104);12 patients underwent balloon dilation,92 patients underwent balloon dilation combined stent.There were 8 cases (8/104,7.69 %) with periprocedural complications,included arterial thrombosis (n =2),pseudoaneurysm (n=1),heart failure (n=4),and radiographic contrast nephropathy (n=1).Doppler ankle-brachial index increased from 0.32±0.12 to 0.81±0.11 (P<0.01) at 1 week after treatment.The patency rates were 88.46 % (69/78) and 81.13% (43/53) at 6 and 12 months followed-up respectively.Conclusion Minimally invasive endovascular treatment has high technical success rate,low complication rate,and satisfactory clinical curative effect for iliac femoral artery occlusive disease of TASC C,D lesions in elderly patients.
9.Under the guidance of defended field theory the effect of hoop confining method on treatment of rats with skin abscess
Zhaohui ZHANG ; Chaojun ZHU ; Yang ZHANG ; Qiang XU ; Yue GUO ; Likun ZHAO ; Tingting HU ; Wanying WANG ; Xiaona JI
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2017;24(1):58-62
Objective To observe the therapeutic effect of hoop circumference drug,Hongzhongxiao tincture,on the treatment of skin abscess in rats under the guidance of defended field theory.Methods Forty SpragueDawley (SD) rats were randomly divided into normal control group,model group,western medicine control group,Hongzhongxiao pretreatment group and Hongzhongxiao treatment group according to the computer generated random number.Subcutaneous abscesses models were reproduced by subcutaneous injection of 1 mL (3-5 × 109 cfu/mL) of staphylococcus aureus,and the normal control group was subcutaneously injected with the same amount of normal saline.After molding,the rats in the model group were treated with normal saline for change of dressing;the western medicine control group was treated with mupirocin ointment for external use;Hongzhongxiao pretreatment group was treated with 2 mL of Hongzhongxiao for dressing 4 hours after the modeling;in Hongzhongxiao treatment group,2 mL dressing was given after the emergence of hard swelling,and the Hongzhongxiao drug range applied was 1 cm over the swelling range.Each group was dressed once daily.The changes of mental state,body weight,skin temperature,range and time of abscess formation,wound ulceration and healing time,transcutaneous oxygen pressure (TcPO2) at the periphery of abscess were observed in each group.Results ① After modeling,the activity of the rats was decreased,the appetite became worse,and the food intake less.Except the normal control group,the rats in other groups had different degrees of mental listlessness.② After 3 days of treatment,the body weight gain of the model group was significantly lower than that of the normal control group (g:8.75 ± 9.85 vs.31.67 ± 7.92,P < 0.01),and continued to 18 days after treatment (g:27.13± 11.70 vs.98.00 ± 8.94);after treatment for 18 days,the body weight gain in the western medicine control group,Hongzhongxiao pretreatment group and Hongzhongxiao treatment group was significantlyhigher than those of model group (g:53.28 ± 19.69,49.12 ± 7.23,44.71 ± 12.42 vs.27.13 ± 11.70,all P < 0.05).③ After 3 days of treatment,the body temperature of the model group was obviously lower than that of the normal control group (℃:33.75 ± 0.68 vs.35.03 ± 0.41,P < 0.01) and continued to 10 days (℃:34.30 ± 0.35 vs.35.03 ± 0.41,P < 0.01).The body temperature of the rats in Hongzhongxiao pretreatment group was significantly lower than that in the normal control group,the model group and the western medicine control group on the 14th day after treatment (℃:33.97 ± 0.83 vs.35.10 ± 0.57,35.01 ± 0.68,35.25 ± 0.23,all P < 0.05).The body temperature of Hongzhongxiao treatment group was significantly higher than that of the Hongzhongxiao pretreatment group (℃:34.87 ± 0.94 vs.33.97 ± 0.83,P <0.05).④ After treatment for 13,15,17 days,the contraction rates of swollen area in western medicine control group,hongzhongxiao pretreatment group and hongzhongxiao treatment group were greater than the rate in model group,and the change was most significant on the 17th day after treatment [(96.37 ± 5.09)%,(92.76 ± 13.56)%,(98.41 ± 3.85)% vs.(77.46 ± 19.07)%,all P < 0.05].⑤ Compared with the model group,the times of abscess localization in the western medicine control group,the Hongzhongxiao pretreatment group and the Hongzhongxiao treatment group was shorter than that in the model group (days:9.28 ± 1.38,7.33 ± 1.97,7.67 ± 1.63 vs.12.63 ± 1.99,all P < 0.05);the time of wound healing in Hongzhongxiao pretreatment group aud Hongzhongxiao treatment group were significantly shorter than those of the model group (days:17.67 ± 1.03,16.83 ± 1.51 vs.19.92 ± 2.33,P < 0.05).⑥ TcPO2 in the Hongzhongxiao pretreatment group was significantly higher than that in the model group on the 7th day after treatment [mmHg (1 mmHg =0.133 kPa):63.33 ± 9.77 vs.39.51 ± 8.42],and the Hongzhongxiao treatment group (44.25 ± 6.41) was significantly lower than that of the Hongzhongxiao pretreatment group,and the Hongzhongxiao treatment group was significantly higher than that of the model group (59.50 ± 7.34 vs.49.52 ± 10.17) on the 14th day after drug application,and the western medicine control group was significantly lower than that of the model group (37.71 ± 5.63 vs.54.33 ± 7.74),the Hongzhongxiao pretreatment group and Hongzhongxiao treatment group were significantly higher than those of the western medicine control group,the difference being statistically significant (all P < 0.05).Conclusions The Hongzhongxiao tincture applied on top and circumferentially around the periphery of the abscess can reduce the local inflammatory response,improve the body weight and mental state,increase the blood supply around wound periphery for anti-infection and anti-inflammation in order to promote the formation of defending field of nursing.Although the early application of Hongzhongxiao tincture cannot reduce the local infectious symptoms and kill the Staphylococcus aureus,it can make skin abscess localization as soon as possible and shorten the wound healing time.
10.Surgical types selection of chronic suppurative otitis media tympanoplasty and its clinical curative effect analysis
Min FANG ; Chaojun LI ; Li YANG ; Shaojing KUANG ; Junwei XIONG ; Biqiang LI ; Yu HUANG ; Yan ZHAO
Chongqing Medicine 2016;45(11):1496-1498,1501
Objective To summary the experience of surgical types selection of chronic suppurative otitis media tympano‐plasty and evaluate its clinical curative effect .Methods Chronic suppurative otitis media patient records were collected ,surgical types selection based on hearing ,otoscope and mastoid CT selection .Finally 161 chronic suppurative otitis media patients (164 ears) whoes medical records and follow‐up of contents were complete were collected ,in which type Ⅰ tympanoplasty group with 40 ears , intact bridge radical mastoidectomy+ type Ⅰ tympanoplasty group with 30 ears ,and open radical mastoidectomy+type Ⅱ tympan‐oplasty group with 94 ears .The therapeutic effects of the three surgical methods for the treatment of chronic suppurative otitis media were evaluated from hearing ,quality of life as well as satisfactory score after surgery .Results The mean values of the air conductive hearing thresholds after operation in the three tympanoplasty groups were decreased than those before operation (all P<0 .05) ,while the mean values of the bone conductive hearing thresholds after operation showed no obvious changes (all P>0 .05) .There were no statistically significant improvements in the air conductive hearing thresholds in the three tympanoplasty groups (P>0 .05) .The improvements in patient′s subjective hearing of the there surgical methods were 82 .5% ,70 .0% and 83 .0%respectively ,there was no statistically significant (P>0 .05) .The improvements in the overall quality of life of the three surgical methods were 80 .0% ,80 .0% and 79 .8% respectively ,showed no statistically significant differences (P>0 .05);the reduction rate of patient′s worry about illness were 90 .0% ,93 .3% and 95 .7% ,showed no statistically significant differences (P>0 .05);the bas‐ic satisfaction rates in the postoperative satisfaction ratings of the three surgical methods were 100 .0% ,100 .0% and 97 .9% ,and there were no statistically significant differences (P>0 .05) .Conclusion For tympanoplasty in chronic suppurative otitis media pa‐tients ,surgical types selection based on hearing ,otoscope ,mastoid CT selection and intraoperative findings .From the evaluation of postoperative patients with hearing and quality of life ,three surgical methods of chronic suppurative otitis media Tympanoplasty a‐chieve satisfactory results .


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