[目的]了解粉尘作业人员直接数字化X射线摄影(direct digital radiography,DR)胸片质量,分析DR胸片降级的主要原因,探讨提高DR胸片质量的措施。[方法]随机选取粉尘作业人员DR胸片500张,对DR胸片质量进行评判。[结果]车载组优片率(70.3%...[目的]了解粉尘作业人员直接数字化X射线摄影(direct digital radiography,DR)胸片质量,分析DR胸片降级的主要原因,探讨提高DR胸片质量的措施。[方法]随机选取粉尘作业人员DR胸片500张,对DR胸片质量进行评判。[结果]车载组优片率(70.3%)低于室内组优片率(83.2%),车载组差片率(12.5%)高于室内组(3.7%),差异均有统计学意义(P<0.01)。造成DR胸片降级的原因中,车载组主要原因为肩胛骨与肺野重叠和肺野内异物影,分别占47.8%和34.8%,室内组主要原因为肩胛骨与肺野重叠,占68.9%。[结论]人为因素是造成粉尘作业人员DR胸片质量下降的主要原因。在实际工作中,应完善DR胸片的质量控制体系,提高投照技师的责任心及操作技能。展开更多
目的:探讨D-二聚体(D-dimer,D-D)与白蛋白(albumin,ALB)比值(D-dimer to albumin ratio,DAR)联合乳酸(lactic acid,Lac)与EICU脓毒症患者严重程度和预后的相关性。方法:选择2018年8月—2024年6月入住河北医科大学哈励逊国际和平医院急...目的:探讨D-二聚体(D-dimer,D-D)与白蛋白(albumin,ALB)比值(D-dimer to albumin ratio,DAR)联合乳酸(lactic acid,Lac)与EICU脓毒症患者严重程度和预后的相关性。方法:选择2018年8月—2024年6月入住河北医科大学哈励逊国际和平医院急救医学部EICU的符合脓毒症诊断条件的患者202例,记录患者性别、年龄、个人史及既往病史等情况,收集患者入院24 h内的序贯器官衰竭估计评分(sequential organ failure assessment,SOFA)及实验室常规检测指标:血常规、D-D、ALB、Lac、降钙素原(procalcitonin,PCT)等。根据2016年美国重症医学会(SCCM)与欧洲重症医学会(ESICM)联合发布脓毒症3.0定义及诊断标准将患者分为脓毒症组(97例)和脓毒性休克组(105例),比较两组患者的一般情况、炎性指标、组织灌注指标以及DAR,分析各指标间的相关性;随访28 d,根据存活与否分为存活组和死亡组,采用多因素logistic回归分析筛选脓毒症患者28 d死亡的危险因素;采用受试者工作特征曲线(ROC曲线)分析DAR对该类患者群的28 d死亡的预测价值。采用MedCalc软件比较常规观察指标与DAR评估的差异性。结果:与脓毒性休克组比较,脓毒症组患者中男性患者更多见(79.4%,P<0.01);与脓毒症非休克组相比,脓毒性休克患者的DAR、Lac、PCT、以及SOFA评分均明显升高;脓毒症患者入EICU 24 h内的DAR与Lac、PCT均有一定的正相关,其中与SOFA评分相关性最强(r=0.512,P<0.001)。绘制DAR及Lac预测脓毒症患者死亡预后的ROC曲线,结果显示,DAR对脓毒症患者28 d死亡预测价值较高(AUCDAR=0.660,AUCLac=0.618);经MedCalc软件分析,DAR评价脓毒症患者预后的灵敏度为85.5%,特异度为47.4%,最佳界值为0.47(Youden index=0.229);与Lac联合检测并未发现预测价值有明显提高(AUC联合=0.663,P>0.05)。Kaplan-Meier生存曲线显示,DAR≥0.47的脓毒症患者28 d病死率明显高于DAR<0.47组(χ^(2)=9.503,P=0.002),且EICU住院时间、接受机械通气比例与时间也明显增高(P<0.05)。结论:DAR对EICU脓毒症患者的病情严重程度和预后评估有一定价值,联合Lac并未发现评估效能有更明显的增高。展开更多
This paper presents the results of a study concerned with the surface hardening of Fe-based alloys and WC-8Co cemented carbide by inte-grating laser cladding and the electrospark deposition processes.Specimens of low ...This paper presents the results of a study concerned with the surface hardening of Fe-based alloys and WC-8Co cemented carbide by inte-grating laser cladding and the electrospark deposition processes.Specimens of low carbon steel were processed firstly by laser cladding with Fe-based alloy powders and then by electrospark deposition with WC-SCo cemented carbide.It is shown that,for these two treatments,the electrospark coating possesses finer microstructure than the laser coating,and the thickness and surface hardness of the electrospark coating can be substantially increased.展开更多
Electro-spark deposition(ESD)was adopted for preparing high property coatings by depositing WC-8Co cemented carbide on an spheroidal graphite roll substrate.The microstructure and properties of the coating were invest...Electro-spark deposition(ESD)was adopted for preparing high property coatings by depositing WC-8Co cemented carbide on an spheroidal graphite roll substrate.The microstructure and properties of the coating were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM)with energy dispersive X-ray(EDX)and ball-disc configuration wear tester.The results show that nanosized particles and amorphous structures prevail in the coating which is metallurgically bonded to the substrate.The microstructures of the transition zone include columnar structure and equiaxed structure.The primary phases of the coating contain W2C,W6C2.54,Fe3W3C,and Co3W3C.The results of abrasive test show that the coating has low friction coefficients(μaverage=0.18)and the wear mechanisms are mainly abrasive wear,fatigue wear,and oxidation wear.The maximum microhardness value of the coating is about 17410 N/mm2.The study reveals that the electro-spark deposition process has better coating quality and the coating has high wear resistance and hardness.展开更多
文摘[目的]了解粉尘作业人员直接数字化X射线摄影(direct digital radiography,DR)胸片质量,分析DR胸片降级的主要原因,探讨提高DR胸片质量的措施。[方法]随机选取粉尘作业人员DR胸片500张,对DR胸片质量进行评判。[结果]车载组优片率(70.3%)低于室内组优片率(83.2%),车载组差片率(12.5%)高于室内组(3.7%),差异均有统计学意义(P<0.01)。造成DR胸片降级的原因中,车载组主要原因为肩胛骨与肺野重叠和肺野内异物影,分别占47.8%和34.8%,室内组主要原因为肩胛骨与肺野重叠,占68.9%。[结论]人为因素是造成粉尘作业人员DR胸片质量下降的主要原因。在实际工作中,应完善DR胸片的质量控制体系,提高投照技师的责任心及操作技能。
文摘This paper presents the results of a study concerned with the surface hardening of Fe-based alloys and WC-8Co cemented carbide by inte-grating laser cladding and the electrospark deposition processes.Specimens of low carbon steel were processed firstly by laser cladding with Fe-based alloy powders and then by electrospark deposition with WC-SCo cemented carbide.It is shown that,for these two treatments,the electrospark coating possesses finer microstructure than the laser coating,and the thickness and surface hardness of the electrospark coating can be substantially increased.
基金supported by the International Science and Technology Cooperation Project of the Ministry of Science and Technology of China(No.2006DFA52240)
文摘Electro-spark deposition(ESD)was adopted for preparing high property coatings by depositing WC-8Co cemented carbide on an spheroidal graphite roll substrate.The microstructure and properties of the coating were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM)with energy dispersive X-ray(EDX)and ball-disc configuration wear tester.The results show that nanosized particles and amorphous structures prevail in the coating which is metallurgically bonded to the substrate.The microstructures of the transition zone include columnar structure and equiaxed structure.The primary phases of the coating contain W2C,W6C2.54,Fe3W3C,and Co3W3C.The results of abrasive test show that the coating has low friction coefficients(μaverage=0.18)and the wear mechanisms are mainly abrasive wear,fatigue wear,and oxidation wear.The maximum microhardness value of the coating is about 17410 N/mm2.The study reveals that the electro-spark deposition process has better coating quality and the coating has high wear resistance and hardness.
