目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)联合序贯器官衰竭评分(sequential organ failure assessment,SOFA)对烧伤脓毒症患者预后的评估价值。方法 选择2021年1月~2022年4月在广州市红十字会医院烧伤...目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)联合序贯器官衰竭评分(sequential organ failure assessment,SOFA)对烧伤脓毒症患者预后的评估价值。方法 选择2021年1月~2022年4月在广州市红十字会医院烧伤科住院的烧伤脓毒症患者73例。根据患者28天的预后情况,分为存活组(52例)和死亡组(21例)。比较在入院时(T_(1))、脓毒症确诊时(T_(2))、脓毒症确诊后第3天(T_(3))3个时间点两组患者白细胞计数(white blood cell count,WBC)、降钙素原(procalcitonin,PCT)、NLR、SOFA评分和急性生理及慢性健康状况(Acute Physiology and Chronic Health Evaluation,APACHEⅡ)评分的差别。同时分析在脓毒症确诊时(T_(2))PCT、NLR、SOFA评分、NLR联合SOFA评分预测烧伤脓毒症患者死亡的受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)。结果 在T_(1)~T_(3) 3个时间点,WBC在存活组和死亡组间比较,差异无统计学意义(P>0.05);在T_(2)和T_(3)时间点,PCT在两组间比较差异有统计学意义(P<0.05);在T_(1)~T_(3)时间点,NLR在两组间比较差异有统计学意义(P<0.05);在T_(2)和T_(3)时间点,SOFA评分在两组间比较差异有统计学意义(P<0.05);在T_(3)时间点,APACHEⅡ评分在两组间比较差异有统计学意义(P<0.05)。在脓毒症确诊时(T_(3)),PCT预测烧伤脓毒症患者预后的ROC曲线下面积(AUC)为0.697(P=0.010),阈值为14.145(敏感度为72.0%,特异性为87.5%);NLR预测效能的AUC为0.761(P<0.001),阈值是11.465(敏感度为81.0%,特异性为75.5%);SOFA评分预测效能的AUC为0.715(P=0.004),阈值为10.500(敏感度为75.0%,特异性为78.1%);NLR与SOFA评分联合预测时,AUC为0.890(P<0.001),预测效果优于其中任何一项单独预测时的效能。结论 NLR和SOFA评分是烧伤脓毒症患者死亡的独立危险因素,两者联合预测烧伤脓毒症患者死亡风险时,其预测能力明显提高,为临床工作提供一定的指导。展开更多
The natural gas components and geochemistry of 38 ultra-deep gas wells(burial depth greater than 6 000 m) in the Sichuan Basin were analyzed to determine the genesis of ultra-deep natural gas in the basin. The ultra-d...The natural gas components and geochemistry of 38 ultra-deep gas wells(burial depth greater than 6 000 m) in the Sichuan Basin were analyzed to determine the genesis of ultra-deep natural gas in the basin. The ultra-deep natural gas components of the basin have the following characteristics: Methane has an absolute advantage, which can be up to 99.56% with an average of 86.6%; ethane is low, with an average of 0.13%; there is nearly no propane and butane. So it is dry gas at over-mature thermal stage. The content of H2 S can be up to 25.21%, with an average of 5.45%. The alkane gas isotopes are: the carbon isotope varies from-32.3‰ to-26.7‰ for methane and from-32.9‰ to-22.1‰ for ethane. There is nearly no carbon isotopic reversal among methane and its homologues. Hydrogen isotope varies from-156‰ to-114‰ for methane, and from-103‰ to-89‰ for some ethane. The carbon isotope of CO_2 varies from-17.2‰ to 1.9‰ and most of them fall within the range of 0±3‰. According to the δ^(13)C_1-δ^(13)C_2-δ^(13)C_3 plot, except some wells, all other ultra-deep gas wells are dominated by coal-derived gas. Based on the CO_2 origin distinguishing plot and δ^(13)C_(CO_2), except some individual wells, most of the ultra-deep CO_2 are of carbonate metamorphic origin. H2 S in the ultra-deep layer of Longgang and Yuanba gas fields belongs to thermochemical sulfate reduction(TSR), while H2 S from Well Shuangtan belongs to thermal decomposition of sulfides(TDS).展开更多
Low maturity coal samples were taken from the Ordos Basin to conduct gold tube thermal simulation experiment in a closed system,and the characteristics of the products were analyzed to find out the fractionation mecha...Low maturity coal samples were taken from the Ordos Basin to conduct gold tube thermal simulation experiment in a closed system,and the characteristics of the products were analyzed to find out the fractionation mechanism of carbon isotopes and the causes of abnormal carbon isotopic compositions of natural gas.At the heating rates of 2℃/h(slow)and 20℃/h(rapid),the low maturity coal samples of the Ordos Basin had the maximum yields of alkane gas of 302.74 mL/g and 230.16 mL/g,theδ13C1 ranges of-34.8‰to-23.6‰and-35.5‰to-24.0‰;δ13C2 ranges of-28.0‰to-9.0‰and-28.9‰to-8.3‰;andδ13C3 ranges of-25.8‰to-14.7‰and-26.4‰to-13.2‰,respectively.Alkane gas in the thermal simulation products of rapid temperature rise process showed obvious partial reversal of carbon isotope series at 550℃,and at other temperatures showed positive carbon isotope series.In the two heating processes,theδ13C1 turned lighter first and then heavier,and the non-monotonic variation of theδ13C1 values is because the early CH4 is from different parent materials resulted from heterogeneity of organic matter or the carbon isotope fractionation formed by activation energy difference of early enriched 12CH4 and late enriched 13CH4.The reversal of carbon isotope values of heavy hydrocarbon gas can occur not only in high to over mature shale gas(oil-type gas),but also in coal-derived gas.Through thermal simulation experiment of toluene,it is confirmed that the carbon isotope value of heavy hydrocarbon gas can be reversed and inversed at high to over mature stage.The isotope fractionation effect caused by demethylation and methyl linkage of aromatic hydrocarbons may be an important reason for carbon isotope inversion and reversal of alkane gas at the high to over mature stage.展开更多
文摘目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)联合序贯器官衰竭评分(sequential organ failure assessment,SOFA)对烧伤脓毒症患者预后的评估价值。方法 选择2021年1月~2022年4月在广州市红十字会医院烧伤科住院的烧伤脓毒症患者73例。根据患者28天的预后情况,分为存活组(52例)和死亡组(21例)。比较在入院时(T_(1))、脓毒症确诊时(T_(2))、脓毒症确诊后第3天(T_(3))3个时间点两组患者白细胞计数(white blood cell count,WBC)、降钙素原(procalcitonin,PCT)、NLR、SOFA评分和急性生理及慢性健康状况(Acute Physiology and Chronic Health Evaluation,APACHEⅡ)评分的差别。同时分析在脓毒症确诊时(T_(2))PCT、NLR、SOFA评分、NLR联合SOFA评分预测烧伤脓毒症患者死亡的受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)。结果 在T_(1)~T_(3) 3个时间点,WBC在存活组和死亡组间比较,差异无统计学意义(P>0.05);在T_(2)和T_(3)时间点,PCT在两组间比较差异有统计学意义(P<0.05);在T_(1)~T_(3)时间点,NLR在两组间比较差异有统计学意义(P<0.05);在T_(2)和T_(3)时间点,SOFA评分在两组间比较差异有统计学意义(P<0.05);在T_(3)时间点,APACHEⅡ评分在两组间比较差异有统计学意义(P<0.05)。在脓毒症确诊时(T_(3)),PCT预测烧伤脓毒症患者预后的ROC曲线下面积(AUC)为0.697(P=0.010),阈值为14.145(敏感度为72.0%,特异性为87.5%);NLR预测效能的AUC为0.761(P<0.001),阈值是11.465(敏感度为81.0%,特异性为75.5%);SOFA评分预测效能的AUC为0.715(P=0.004),阈值为10.500(敏感度为75.0%,特异性为78.1%);NLR与SOFA评分联合预测时,AUC为0.890(P<0.001),预测效果优于其中任何一项单独预测时的效能。结论 NLR和SOFA评分是烧伤脓毒症患者死亡的独立危险因素,两者联合预测烧伤脓毒症患者死亡风险时,其预测能力明显提高,为临床工作提供一定的指导。
基金Supported by the China National Science and Technology Major Project(2016ZX05007-001)
文摘The natural gas components and geochemistry of 38 ultra-deep gas wells(burial depth greater than 6 000 m) in the Sichuan Basin were analyzed to determine the genesis of ultra-deep natural gas in the basin. The ultra-deep natural gas components of the basin have the following characteristics: Methane has an absolute advantage, which can be up to 99.56% with an average of 86.6%; ethane is low, with an average of 0.13%; there is nearly no propane and butane. So it is dry gas at over-mature thermal stage. The content of H2 S can be up to 25.21%, with an average of 5.45%. The alkane gas isotopes are: the carbon isotope varies from-32.3‰ to-26.7‰ for methane and from-32.9‰ to-22.1‰ for ethane. There is nearly no carbon isotopic reversal among methane and its homologues. Hydrogen isotope varies from-156‰ to-114‰ for methane, and from-103‰ to-89‰ for some ethane. The carbon isotope of CO_2 varies from-17.2‰ to 1.9‰ and most of them fall within the range of 0±3‰. According to the δ^(13)C_1-δ^(13)C_2-δ^(13)C_3 plot, except some wells, all other ultra-deep gas wells are dominated by coal-derived gas. Based on the CO_2 origin distinguishing plot and δ^(13)C_(CO_2), except some individual wells, most of the ultra-deep CO_2 are of carbonate metamorphic origin. H2 S in the ultra-deep layer of Longgang and Yuanba gas fields belongs to thermochemical sulfate reduction(TSR), while H2 S from Well Shuangtan belongs to thermal decomposition of sulfides(TDS).
基金Supported by the National Natural Science Foundation of China(41902160,41625009)the China Postdoctoral Science Foundation(2019M650967,2020T130721)the China National Science and Technology Major Project(2016ZX05007-001)
文摘Low maturity coal samples were taken from the Ordos Basin to conduct gold tube thermal simulation experiment in a closed system,and the characteristics of the products were analyzed to find out the fractionation mechanism of carbon isotopes and the causes of abnormal carbon isotopic compositions of natural gas.At the heating rates of 2℃/h(slow)and 20℃/h(rapid),the low maturity coal samples of the Ordos Basin had the maximum yields of alkane gas of 302.74 mL/g and 230.16 mL/g,theδ13C1 ranges of-34.8‰to-23.6‰and-35.5‰to-24.0‰;δ13C2 ranges of-28.0‰to-9.0‰and-28.9‰to-8.3‰;andδ13C3 ranges of-25.8‰to-14.7‰and-26.4‰to-13.2‰,respectively.Alkane gas in the thermal simulation products of rapid temperature rise process showed obvious partial reversal of carbon isotope series at 550℃,and at other temperatures showed positive carbon isotope series.In the two heating processes,theδ13C1 turned lighter first and then heavier,and the non-monotonic variation of theδ13C1 values is because the early CH4 is from different parent materials resulted from heterogeneity of organic matter or the carbon isotope fractionation formed by activation energy difference of early enriched 12CH4 and late enriched 13CH4.The reversal of carbon isotope values of heavy hydrocarbon gas can occur not only in high to over mature shale gas(oil-type gas),but also in coal-derived gas.Through thermal simulation experiment of toluene,it is confirmed that the carbon isotope value of heavy hydrocarbon gas can be reversed and inversed at high to over mature stage.The isotope fractionation effect caused by demethylation and methyl linkage of aromatic hydrocarbons may be an important reason for carbon isotope inversion and reversal of alkane gas at the high to over mature stage.
