目的探究术前纤维蛋白原与血浆白蛋白比值(fibrinogen to albumin ratio,FAR)与直肠癌患者临床病理特征及预后的相关性,以明确凝血功能及营养状态在肿瘤发生发展中的作用。方法回顾性分析2013年1月至2016年12月西安交通大学第一附属医...目的探究术前纤维蛋白原与血浆白蛋白比值(fibrinogen to albumin ratio,FAR)与直肠癌患者临床病理特征及预后的相关性,以明确凝血功能及营养状态在肿瘤发生发展中的作用。方法回顾性分析2013年1月至2016年12月西安交通大学第一附属医院收治的647例行直肠癌根治术患者的临床病理资料。将647例直肠癌患者按照受试者工作特征(receiver operating characteristic,ROC)曲线确定的术前FAR水平的最佳截点值分为高水平FAR组与低水平FAR组。分析直肠癌患者术前FAR不同水平与临床病理特征间的关系,采用多因素COX回归分析方法分析直肠癌患者预后的独立危险因素。应用R软件构建列线图,并使用C指数及校准图评价列线图预测效能。结果术前FAR水平对直肠癌患者预后有较好的预测价值,ROC曲线下面积为0.771,最佳截点值为0.092,约登指数为0.446。术前不同水平FAR直肠癌患者年龄、T分期、N分期、TNM分期、血清中癌胚抗原(CEA)及糖链抗原(CA19-9)差异均有统计学意义(P<0.05)。术前不同FAR水平的直肠癌患者总生存期(overall survival,OS)与无病生存期(disease-free survival,DFS)差异有统计学意义(均P<0.05)。在多因素COX回归分析中,术前FAR水平(≥0.092,HR=3.298,95%CI:2.365~4.600,P<0.001)、年龄(≥60岁,HR=2.110,95%CI:1.479~3.012,P<0.001)、TNM期(Ⅲ期,HR=6.743,95%CI:2.771~16.771,P<0.001)、分化程度(低分化,HR=1.639,95%CI:1.104~2.432,P=0.014)、术前CA19-9水平(≥37,HR=2.205,95%CI:1.529~3.180,P<0.001)以及术后未行辅助放化疗(HR=1.792,95%CI:1.294~2.480,P<0.001)是直肠癌患者预后的独立危险因素。将多因素结果纳入R语言构建直肠癌患者OS、DFS列线图,C指数分别为0.781,95%CI:0.749~0.815;0.754,95%CI:0.693~0.760,列线图1、3、5年OS、DFS校准图均展现了较好的拟合度。结论术前高水平FAR是直肠癌患者预后的独立危险因素,其可与TNM分期等病理因素相互补充作为直肠癌患者的预后指标,为患者术后长期管理和治疗提供参考。展开更多
山西宝山某难选铁矿石以磁铁矿为主,目的矿物呈浸染状嵌布于脉石中,现场设计采用高压辊磨预选+两段球磨阶段磨选流程,难以获得合格的铁精矿。为提高最终精矿指标,考察了螺旋立磨磨选代替二段球磨磨选工艺。通过螺旋立磨磨选工艺对比,确...山西宝山某难选铁矿石以磁铁矿为主,目的矿物呈浸染状嵌布于脉石中,现场设计采用高压辊磨预选+两段球磨阶段磨选流程,难以获得合格的铁精矿。为提高最终精矿指标,考察了螺旋立磨磨选代替二段球磨磨选工艺。通过螺旋立磨磨选工艺对比,确定了最优磨选方案及磨机选型依据磨矿功指数。通过两段螺旋立磨磨选工艺,在-0.028 mm 95%的细度条件下,最终获得了全铁品位为65.59%、铁回收率为71.37%的合格铁精矿。展开更多
Coarse-resolution satellite albedo products are important for climate change and energy balance research because of their capability to characterize the spatiotemporal patterns of land surface parameters at both the r...Coarse-resolution satellite albedo products are important for climate change and energy balance research because of their capability to characterize the spatiotemporal patterns of land surface parameters at both the regional and global scales. The accuracy of coarse-resolution products is usually assessed via comparison with in situ measurements. The key issue in the comparison of remote sensing observations with in situ measurements is scaling and uncertainty. This paper presents a strategy for validating 1-km-resolution remote sensing albedo products using field measurements and high-resolution remote sensing observations. Field measurements were collected to calibrate the high-resolution(30 m) albedo products derived from HJ-1a/b images. Then, the calibrated high-resolution albedo maps were resampled(i.e., upscaled) to assess the accuracy of the coarse-resolution albedo products. The samples of field measurements and high-resolution pixels are based on an uncertainty analysis. Two types of coarse-resolution albedo datasets, from global land surface satellite(GLASS) and moderate-resolution imaging spectroradiometer(MODIS), are validated over the middle reaches of the Heihe River in China. The results indicate that the upscaled HJ(Huan Jing means environment in Chinese and this refers to a satellite constellation designed for environment and disaster monitoring by China) albedo, which was calibrated using field measurements, can provide accurate reference values for validating coarse-resolution satellite albedo products. However, the uncertainties in the upscaled HJ albedo should be estimated, and pixels with large uncertainties should be excluded from the validation process.展开更多
文摘目的探究术前纤维蛋白原与血浆白蛋白比值(fibrinogen to albumin ratio,FAR)与直肠癌患者临床病理特征及预后的相关性,以明确凝血功能及营养状态在肿瘤发生发展中的作用。方法回顾性分析2013年1月至2016年12月西安交通大学第一附属医院收治的647例行直肠癌根治术患者的临床病理资料。将647例直肠癌患者按照受试者工作特征(receiver operating characteristic,ROC)曲线确定的术前FAR水平的最佳截点值分为高水平FAR组与低水平FAR组。分析直肠癌患者术前FAR不同水平与临床病理特征间的关系,采用多因素COX回归分析方法分析直肠癌患者预后的独立危险因素。应用R软件构建列线图,并使用C指数及校准图评价列线图预测效能。结果术前FAR水平对直肠癌患者预后有较好的预测价值,ROC曲线下面积为0.771,最佳截点值为0.092,约登指数为0.446。术前不同水平FAR直肠癌患者年龄、T分期、N分期、TNM分期、血清中癌胚抗原(CEA)及糖链抗原(CA19-9)差异均有统计学意义(P<0.05)。术前不同FAR水平的直肠癌患者总生存期(overall survival,OS)与无病生存期(disease-free survival,DFS)差异有统计学意义(均P<0.05)。在多因素COX回归分析中,术前FAR水平(≥0.092,HR=3.298,95%CI:2.365~4.600,P<0.001)、年龄(≥60岁,HR=2.110,95%CI:1.479~3.012,P<0.001)、TNM期(Ⅲ期,HR=6.743,95%CI:2.771~16.771,P<0.001)、分化程度(低分化,HR=1.639,95%CI:1.104~2.432,P=0.014)、术前CA19-9水平(≥37,HR=2.205,95%CI:1.529~3.180,P<0.001)以及术后未行辅助放化疗(HR=1.792,95%CI:1.294~2.480,P<0.001)是直肠癌患者预后的独立危险因素。将多因素结果纳入R语言构建直肠癌患者OS、DFS列线图,C指数分别为0.781,95%CI:0.749~0.815;0.754,95%CI:0.693~0.760,列线图1、3、5年OS、DFS校准图均展现了较好的拟合度。结论术前高水平FAR是直肠癌患者预后的独立危险因素,其可与TNM分期等病理因素相互补充作为直肠癌患者的预后指标,为患者术后长期管理和治疗提供参考。
文摘山西宝山某难选铁矿石以磁铁矿为主,目的矿物呈浸染状嵌布于脉石中,现场设计采用高压辊磨预选+两段球磨阶段磨选流程,难以获得合格的铁精矿。为提高最终精矿指标,考察了螺旋立磨磨选代替二段球磨磨选工艺。通过螺旋立磨磨选工艺对比,确定了最优磨选方案及磨机选型依据磨矿功指数。通过两段螺旋立磨磨选工艺,在-0.028 mm 95%的细度条件下,最终获得了全铁品位为65.59%、铁回收率为71.37%的合格铁精矿。
基金sponsored by the National Basic Research Program of China(Grant No.2013CB733401)the National High Technology Research and Development Program of China(Grant No.2012AA12A300)the National Natural Science Foundation of China(Grant Nos.41273168,41331171)
文摘Coarse-resolution satellite albedo products are important for climate change and energy balance research because of their capability to characterize the spatiotemporal patterns of land surface parameters at both the regional and global scales. The accuracy of coarse-resolution products is usually assessed via comparison with in situ measurements. The key issue in the comparison of remote sensing observations with in situ measurements is scaling and uncertainty. This paper presents a strategy for validating 1-km-resolution remote sensing albedo products using field measurements and high-resolution remote sensing observations. Field measurements were collected to calibrate the high-resolution(30 m) albedo products derived from HJ-1a/b images. Then, the calibrated high-resolution albedo maps were resampled(i.e., upscaled) to assess the accuracy of the coarse-resolution albedo products. The samples of field measurements and high-resolution pixels are based on an uncertainty analysis. Two types of coarse-resolution albedo datasets, from global land surface satellite(GLASS) and moderate-resolution imaging spectroradiometer(MODIS), are validated over the middle reaches of the Heihe River in China. The results indicate that the upscaled HJ(Huan Jing means environment in Chinese and this refers to a satellite constellation designed for environment and disaster monitoring by China) albedo, which was calibrated using field measurements, can provide accurate reference values for validating coarse-resolution satellite albedo products. However, the uncertainties in the upscaled HJ albedo should be estimated, and pixels with large uncertainties should be excluded from the validation process.
