目的探讨Astograph法乙酰甲胆碱气道反应性测定对胸闷变异性哮喘的诊断价值。方法将2011年1月至2017年2月华北理工大学附属开滦总医院呼吸内科门诊或住院的胸闷变异性哮喘患者156例作为病例组(胸闷变异性哮喘组),将同期确诊间质性肺疾病...目的探讨Astograph法乙酰甲胆碱气道反应性测定对胸闷变异性哮喘的诊断价值。方法将2011年1月至2017年2月华北理工大学附属开滦总医院呼吸内科门诊或住院的胸闷变异性哮喘患者156例作为病例组(胸闷变异性哮喘组),将同期确诊间质性肺疾病(23例)、冠心病(157例)、高血压性心脏病(22例)、心肌病(16例)、先天性心脏病(3例)、风湿性心脏瓣膜病(6例)、中心气道病变(3例)、甲状腺肿大(10例)、纵隔肿瘤(5例)、胸廓或脊柱畸形(8例)、膈肌麻痹症(2例)及自主神经功能紊乱(106例)的非哮喘患者361例做为对照组。所有受试者均行肺通气功能检查、呼吸流量峰值(peak expiratory flow,PEF)平均每日昼夜变异率或PEF周变异率、Astograph法乙酰甲胆碱气道反应性测定[基础第一秒用力呼气容积(Forced expiratory volume in one second,FEV1)≥70%预计值时]检查及引起胸闷的各种疾病的相关检查。通过分析Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异型哮喘的敏感度、特异度、阳性预测值、阴性预测值、诊断准确性及Yunden指数,探讨Astograph法乙酰甲胆碱气道反应性测定对胸闷变异型哮喘的诊断价值。结果胸闷变异性哮喘组与对照组比较用力呼气75%肺活量时气道流速差异有统计学意义[1.18±0.44)%与(1.29±0.50)%;t=2.96,P=0.006]。Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异型哮喘的敏感度、特异度、阳性预测值、阴性预测值、Yunden指数及诊断准确性分别为0.81、0.69、0.53、0.30、0.50及0.73。结论Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异性哮喘的敏感度、阴性预测值、Youden指数和诊断准确性均较高,特异度和阳性预测值偏低,提示Astograph法乙酰甲胆碱气道反应性测定对胸闷变异性哮喘有较高的诊断价值,假阴性偏低,假阳性略高。展开更多
A coupled supersonic inlet-fan Navier–Stokes simulation method was developed by using COMSOL-CFD code. The flow turning, pressure rise and loss effects across blade rows of the fan and the inlet-fan interactions were...A coupled supersonic inlet-fan Navier–Stokes simulation method was developed by using COMSOL-CFD code. The flow turning, pressure rise and loss effects across blade rows of the fan and the inlet-fan interactions were taken into account as source terms of the governing equations without a blade geometry by a body force model. In this model, viscous effects in blade passages can also be calculated directly, which include the exchange of momentum between fluids and detailed viscous flow close to walls. NASA Rotor 37 compressor test rig was used to validate the ability of the body force model to estimate the real performance of blade rows. Calculated pressure ratio characteristics and the distribution of the total pressure, total temperature, and swirl angle in the span direction agreed well with experimental and numerical data. It is shown that the body force model is a promising approach for predicting the flow field of the turbomachinery. Then, coupled axisymmetric mixed compression supersonic inlet-fan simulations were conducted at Mach number 2.8 operating conditions. The analysis includes coupled steady-state performance, and effects of the fan on the inlet. The results indicate that the coupled simulation method is capable of simulating behavior of the supersonic inlet-fan system.展开更多
文摘目的探讨Astograph法乙酰甲胆碱气道反应性测定对胸闷变异性哮喘的诊断价值。方法将2011年1月至2017年2月华北理工大学附属开滦总医院呼吸内科门诊或住院的胸闷变异性哮喘患者156例作为病例组(胸闷变异性哮喘组),将同期确诊间质性肺疾病(23例)、冠心病(157例)、高血压性心脏病(22例)、心肌病(16例)、先天性心脏病(3例)、风湿性心脏瓣膜病(6例)、中心气道病变(3例)、甲状腺肿大(10例)、纵隔肿瘤(5例)、胸廓或脊柱畸形(8例)、膈肌麻痹症(2例)及自主神经功能紊乱(106例)的非哮喘患者361例做为对照组。所有受试者均行肺通气功能检查、呼吸流量峰值(peak expiratory flow,PEF)平均每日昼夜变异率或PEF周变异率、Astograph法乙酰甲胆碱气道反应性测定[基础第一秒用力呼气容积(Forced expiratory volume in one second,FEV1)≥70%预计值时]检查及引起胸闷的各种疾病的相关检查。通过分析Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异型哮喘的敏感度、特异度、阳性预测值、阴性预测值、诊断准确性及Yunden指数,探讨Astograph法乙酰甲胆碱气道反应性测定对胸闷变异型哮喘的诊断价值。结果胸闷变异性哮喘组与对照组比较用力呼气75%肺活量时气道流速差异有统计学意义[1.18±0.44)%与(1.29±0.50)%;t=2.96,P=0.006]。Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异型哮喘的敏感度、特异度、阳性预测值、阴性预测值、Yunden指数及诊断准确性分别为0.81、0.69、0.53、0.30、0.50及0.73。结论Astograph法乙酰甲胆碱气道反应性测定诊断胸闷变异性哮喘的敏感度、阴性预测值、Youden指数和诊断准确性均较高,特异度和阳性预测值偏低,提示Astograph法乙酰甲胆碱气道反应性测定对胸闷变异性哮喘有较高的诊断价值,假阴性偏低,假阳性略高。
基金support of National Natural Science Foundation of China (Nos. 51706008 and 51636001)China Postdoctoral Science Foundation (No. 2017M610742)Aeronautics Power Foundation of China (No. 6141B090315)
文摘A coupled supersonic inlet-fan Navier–Stokes simulation method was developed by using COMSOL-CFD code. The flow turning, pressure rise and loss effects across blade rows of the fan and the inlet-fan interactions were taken into account as source terms of the governing equations without a blade geometry by a body force model. In this model, viscous effects in blade passages can also be calculated directly, which include the exchange of momentum between fluids and detailed viscous flow close to walls. NASA Rotor 37 compressor test rig was used to validate the ability of the body force model to estimate the real performance of blade rows. Calculated pressure ratio characteristics and the distribution of the total pressure, total temperature, and swirl angle in the span direction agreed well with experimental and numerical data. It is shown that the body force model is a promising approach for predicting the flow field of the turbomachinery. Then, coupled axisymmetric mixed compression supersonic inlet-fan simulations were conducted at Mach number 2.8 operating conditions. The analysis includes coupled steady-state performance, and effects of the fan on the inlet. The results indicate that the coupled simulation method is capable of simulating behavior of the supersonic inlet-fan system.
