目的分析儿童急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)经中国儿童肿瘤协作组急性淋巴细胞白血病2015方案(Chinese Children's Cancer Group ALL-2015 protocol,CCCG-ALL-2015)治疗后的累积复发率(cumulative incidenc...目的分析儿童急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)经中国儿童肿瘤协作组急性淋巴细胞白血病2015方案(Chinese Children's Cancer Group ALL-2015 protocol,CCCG-ALL-2015)治疗后的累积复发率(cumulative incidence of relapse,CIR),并探讨影响复发的危险因素。方法回顾性分析2015年1月—2019年12月接受CCCG-ALL-2015方案治疗的852例患儿的临床资料,计算CIR并分析影响儿童急性B淋巴细胞白血病(B-ALL)复发的危险因素。结果852例ALL患儿中,146例(17.1%)发生复发,8年CIR为(19.8±1.6)%。B-ALL与急性T淋巴细胞白血病患儿的8年CIR比较差异无统计学意义(P>0.05)。146例复发患儿中,复发时间主要集中于极早期(62例,42.5%)和早期(46例,31.5%),极早期单纯骨髓复发42例(28.8%),早期单纯骨髓复发27例(18.5%)。Cox比例风险回归模型分析显示,融合基因MLLr阳性(HR=4.177,95%CI:2.086~8.364,P<0.001)和第46天微小残留病≥0.01%(HR=2.013,95%CI:1.163~3.483,P=0.012)是B-ALL患儿经CCCG-ALL-2015方案治疗后复发的危险因素。结论儿童ALL经CCCG-ALL-2015方案治疗后仍有较高的复发率,以极早期和早期单纯骨髓复发常见;第46天微小残留病≥0.01%、融合基因MLLr阳性与B-ALL复发密切相关。展开更多
Residual coal pillars play an important role in mining the adjacent coal seam safely,managing the gobs and maintaining the stability of abandoned coal mines.The height to diameter ratio(H/D)affects the stability of re...Residual coal pillars play an important role in mining the adjacent coal seam safely,managing the gobs and maintaining the stability of abandoned coal mines.The height to diameter ratio(H/D)affects the stability of residual coal pillars.In this study,uniaxial compressive tests of coal specimens with five H/D(2.0,1.5,1.0,0.8 and 0.6)were performed,and the stress,strain and acoustic emission(AE)were monitored.Results show that the uniaxial compressive strength(UCS)and peak strain increase with H/D decreasing.An empirical equation is proposed to calculate the UCS based on the H/D.The AE activities during coal failure process can be separated into four periods.The span of quiet period and rapid decline period shorten with H/D decreasing.The smaller the H/D is,the more complicated the failure characteristics of coal will be.The failure form of coal with H/D of 2.0,1.5,and 1.0 is primarily shear failure,while splitting failure along the axial direction is the mainly mode when H/D is 0.8 or 0.6.The initiation,expansion,aggregation and connection of micro-cracks can be reflected by the real-time spatial evolution of AE event points.展开更多
A step-by-step load was utilized to mimic the load history of the backfill column in the in-situ curing process.The inner damage of the specimen during curing and uniaxial compressive testing was monitored by electric...A step-by-step load was utilized to mimic the load history of the backfill column in the in-situ curing process.The inner damage of the specimen during curing and uniaxial compressive testing was monitored by electrical resistivity and ultrasonic equipment.Results show that:1)Uniaxial compressive strength(UCS)and elastic modulus(EM)of the samples curing under pressure are higher than those of the control samples without pressure,ranging in ratio from 0.5%to 20.2%and 7.1%to 52.3%,respectively,and are influenced by the initial loading age(ILA)and stress strength ratio(SSR).The SSR during curing should not exceed 80%.2)The earlier the ILA is,the higher the total strain becomes.The higher the SSR applies,the larger the total strain gets.The creep strain increases with the increase of SSR and can be described by Burger’s viscoelastic creep model.When SSR is less than 80%,the earlier the ILA is,the smaller the creep strain becomes after the last step-loading.3)The stability of the early age backfill column under pressure can be monitored based on the change of ultrasonic pulse velocity(UPV)and electrical resistivity.展开更多
文摘目的分析儿童急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)经中国儿童肿瘤协作组急性淋巴细胞白血病2015方案(Chinese Children's Cancer Group ALL-2015 protocol,CCCG-ALL-2015)治疗后的累积复发率(cumulative incidence of relapse,CIR),并探讨影响复发的危险因素。方法回顾性分析2015年1月—2019年12月接受CCCG-ALL-2015方案治疗的852例患儿的临床资料,计算CIR并分析影响儿童急性B淋巴细胞白血病(B-ALL)复发的危险因素。结果852例ALL患儿中,146例(17.1%)发生复发,8年CIR为(19.8±1.6)%。B-ALL与急性T淋巴细胞白血病患儿的8年CIR比较差异无统计学意义(P>0.05)。146例复发患儿中,复发时间主要集中于极早期(62例,42.5%)和早期(46例,31.5%),极早期单纯骨髓复发42例(28.8%),早期单纯骨髓复发27例(18.5%)。Cox比例风险回归模型分析显示,融合基因MLLr阳性(HR=4.177,95%CI:2.086~8.364,P<0.001)和第46天微小残留病≥0.01%(HR=2.013,95%CI:1.163~3.483,P=0.012)是B-ALL患儿经CCCG-ALL-2015方案治疗后复发的危险因素。结论儿童ALL经CCCG-ALL-2015方案治疗后仍有较高的复发率,以极早期和早期单纯骨髓复发常见;第46天微小残留病≥0.01%、融合基因MLLr阳性与B-ALL复发密切相关。
基金Project(51925402) supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(51974192) supported by the National Natural Science Foundation,ChinaProject(2022SX-TD007) supported by the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Project,China。
基金Projects(51974192,52004172)supported by the National Natural Science Foundation of ChinaProject(51925402)supported by the Distinguished Youth Funds of National Natural Science Foundation of ChinaProject(U1710258)supported by the Joint Funds of National Natural Science Foundation of China and Shanxi Province,China。
文摘Residual coal pillars play an important role in mining the adjacent coal seam safely,managing the gobs and maintaining the stability of abandoned coal mines.The height to diameter ratio(H/D)affects the stability of residual coal pillars.In this study,uniaxial compressive tests of coal specimens with five H/D(2.0,1.5,1.0,0.8 and 0.6)were performed,and the stress,strain and acoustic emission(AE)were monitored.Results show that the uniaxial compressive strength(UCS)and peak strain increase with H/D decreasing.An empirical equation is proposed to calculate the UCS based on the H/D.The AE activities during coal failure process can be separated into four periods.The span of quiet period and rapid decline period shorten with H/D decreasing.The smaller the H/D is,the more complicated the failure characteristics of coal will be.The failure form of coal with H/D of 2.0,1.5,and 1.0 is primarily shear failure,while splitting failure along the axial direction is the mainly mode when H/D is 0.8 or 0.6.The initiation,expansion,aggregation and connection of micro-cracks can be reflected by the real-time spatial evolution of AE event points.
基金Project(51974192)supported by the National Natural Science Foundation of ChinaProject(201803D31044)supported by the Program for Key Research Project of Shanxi Province in the Field of Social Development,ChinaProject(201801D121092)supported by the Applied Basic Research Project of Shanxi Province,China。
文摘A step-by-step load was utilized to mimic the load history of the backfill column in the in-situ curing process.The inner damage of the specimen during curing and uniaxial compressive testing was monitored by electrical resistivity and ultrasonic equipment.Results show that:1)Uniaxial compressive strength(UCS)and elastic modulus(EM)of the samples curing under pressure are higher than those of the control samples without pressure,ranging in ratio from 0.5%to 20.2%and 7.1%to 52.3%,respectively,and are influenced by the initial loading age(ILA)and stress strength ratio(SSR).The SSR during curing should not exceed 80%.2)The earlier the ILA is,the higher the total strain becomes.The higher the SSR applies,the larger the total strain gets.The creep strain increases with the increase of SSR and can be described by Burger’s viscoelastic creep model.When SSR is less than 80%,the earlier the ILA is,the smaller the creep strain becomes after the last step-loading.3)The stability of the early age backfill column under pressure can be monitored based on the change of ultrasonic pulse velocity(UPV)and electrical resistivity.
