Beside many efforts to improve outcome, sepsis is still one of the most frequent causes of death in critically ill patients. It is the most common condition with high mortality in intensive care units. The complexity ...Beside many efforts to improve outcome, sepsis is still one of the most frequent causes of death in critically ill patients. It is the most common condition with high mortality in intensive care units. The complexity of the septic syndrome comprises immunological aspects- i.e.,sepsis induced immunosuppression- but is not restricted to this fact in modern concepts. So far, exact mechanisms and variables determining outcome and mortality stay unclear. Since there is no typical risk profile, early diagnosis and risk stratification remain difficult, which hinders rapid and effective treatment initiation. Due to the heterogeneous nature of sepsis, potential therapy options should be adapted to the individual. Biomarkers like C-reactive protein and procalcitonin are routinely used as complementary tools in clinical decision-making. Beyond the acute phase proteins, a wide bunch of promising substances and non-laboratory tools with potential diagnostic and prognostic value is under intensive investigation. So far, clinical decision just based on biomarker assessment is not yet feasible. However, biomarkers should be considered as a complementary approach.展开更多
背景与目的近年来肺癌发病率和死亡率不断上升,已成为我国恶性肿瘤的首位死因。本研究旨在探讨厦门市居民肺癌死亡和减寿的变化趋势,以期为厦门市肺癌综合防治工作提供依据。方法收集整理2005年-2014年厦门市居民肺癌死亡资料计算死亡...背景与目的近年来肺癌发病率和死亡率不断上升,已成为我国恶性肿瘤的首位死因。本研究旨在探讨厦门市居民肺癌死亡和减寿的变化趋势,以期为厦门市肺癌综合防治工作提供依据。方法收集整理2005年-2014年厦门市居民肺癌死亡资料计算死亡率、平均减寿年数(average potential life lost,AYLL)、死亡率年均变化百分比等评价指标,用GM(1,1)模型对死亡率和AYLL进行预测。结果 2005年-2014年,厦门市居民肺癌死亡率28.58/10万,年均上升4.86%,男性死亡率是女性的2.90倍;AYLL为7.8年,存在下降趋势。GM(1,1)模型预测值与实际值平均相对误差2.16%-8.83%,预测2015年-2019年肺癌死亡率和AYLL值均有所上升。结论厦门市肺癌死亡率逐年升高,未来肺癌死亡率和人均减寿数都有上升趋势,应重视肺癌的预防控制工作。展开更多
目的:应用支持向量机(support vector machine,SVM)构建ICU中急性肾功能损伤(acute kidney injury,AKI)患者住院死亡风险预测模型,并比较其与ICU中常用的简化急性生理评分(the simplified acute physiology scoreⅡ,SAPS-Ⅱ)的预测性能...目的:应用支持向量机(support vector machine,SVM)构建ICU中急性肾功能损伤(acute kidney injury,AKI)患者住院死亡风险预测模型,并比较其与ICU中常用的简化急性生理评分(the simplified acute physiology scoreⅡ,SAPS-Ⅱ)的预测性能。方法:使用重症监护医学信息市场(medical information mart for intensive careⅢ,MIMIC-Ⅲ)数据库作为数据来源。根据2012年国际改善全球肾脏病预后组织(Kidney Disease:Improving Global Outcomes,KDIGO)发表的《急性肾损伤临床实践指南》选取MIMIC-Ⅲ数据库中的AKI患者,使用SAPS-Ⅱ中所用到的全部变量构建SVM模型,同时,使用MIMIC-Ⅲ数据库定制本地化的SAPS-Ⅱ模型,并比较其与SVM模型的性能优劣。模型性能的评价方法使用五折交叉验证,评价指标使用受试者工作特征曲线下面积(area under the receiver operation characteristic curve,AUROC)、均方根误差(root mean squared error,RMSE)、灵敏度、特异度和准确率。此外,使用Bland-Altman图评估两模型预测结果的一致性。结果:共纳入19 044例AKI患者,死亡率为13.58%。五折交叉验证的结果显示,SVM模型和定制版SAPS-Ⅱ模型的平均AUROC分别为0.86和0.81,差异有统计学意义(t=13.0,P<0.001),SVM模型和定制版SAPS-Ⅱ模型的平均RMSE分别为0.29和0.31,差异有统计学意义(t=-9.6,P<0.001)。在灵敏度和约登指数方面,SVM模型也均优于定制版的SAPS-Ⅱ模型,差异均具有统计学意义(P分别为0.002和<0.001)。Bland-Altman图显示当患者死亡风险极高或者极低时,两模型预测结果的一致性较好。当患者死亡风险的不确定性较大时,两模型预测结果的一致性较差。结论:相比于传统的SAPS-Ⅱ模型,SVM模型的预测性能更优,且当患者的死亡风险不确定时,这种优势尤其明显;SVM模型更有利于AKI患者的死亡风险识别与早期干预,能有效地帮助ICU临床医生提高医疗质量,有很强的临床应用价值。展开更多
水库进行水力排沙时,高含沙水流过程可能会对鱼类等水生动物产生负面影响,其量化评估方法研究较为薄弱。为了预测和评估水库排沙过程对下游鱼类的影响,本文利用黄河花斑裸鲤和鲤鱼在高含沙水体中生存特性研究的实验数据,综合考虑含沙量...水库进行水力排沙时,高含沙水流过程可能会对鱼类等水生动物产生负面影响,其量化评估方法研究较为薄弱。为了预测和评估水库排沙过程对下游鱼类的影响,本文利用黄河花斑裸鲤和鲤鱼在高含沙水体中生存特性研究的实验数据,综合考虑含沙量和粒径、溶解氧、暴露时间、水温等因子对鱼类生存的影响,建立了基于IPSO-BP神经网络的高含沙水体对鱼类致死影响预测方法,对目标鱼类死亡率的预测误差小于6%。本文使用了与BP神经网络紧密耦合并引入动态参数和变异扰动的IPSO算法,较BP和PSO-BP神经网络预测能力更佳,相比国内外已有的Stress Index(SI)、Severity of Ill Effect(SEV)和多元拟合方法预测精度得到显著提升。分析表明,本文提出的预测方法能够考虑高含沙水体中鱼类生存受多环境因子联合制约,且多因子之间存在复杂关联的情况,可为评估高含沙水流过程对水生态的影响提供新的方法。展开更多
Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure (AHF). Methods 2486 patients who were 60 ...Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure (AHF). Methods 2486 patients who were 60 years and older from intensive care units of Cardiology De- partment in the hospital were analyzed. Independent risk factors for in-hospital mortality were obtained by binary logistic regression and then used to establish the risk prediction score system (RPSS). The area under the curve (AUC) of receiver operator characteristic and C-statistic test were adopted to assess the performance of RPSS and to compare with previous get with the guidelines-heart failure (GWTG-HF). Re- sults By binary logistic regression analysis, heart rate (OR: 1.043, 95% CI: 1.030-1.057, P 〈 0.001), left ventricular ejection fraction (OR: 0.918, 95% CI: 0.833~).966, P 〈 0.001), pH value (OR: 0.001, 95% CI: 0.000-0.002, P 〈 0.001), renal dysfunction (OR: 0.120, 95% CI: 0.066M).220, P 〈 0.001) and NT-pro BNP (OR: 3.463, 95% CI: 1.870-6.413, P 〈 0.001) were independent risk factors of in-hospital mortal- ity for elderly AHF patients. Additionally, RPSS, which was composed of all the above-mentioned parameters, provided a better risk predic- tion than GWTG-THF (AUC: 0.873 vs. 0.818, P = 0.016). Conclusions Our risk prediction model, RPSS, provided a good prediction for in-hospital mortality in elderly patients with A/IF.展开更多
文摘Beside many efforts to improve outcome, sepsis is still one of the most frequent causes of death in critically ill patients. It is the most common condition with high mortality in intensive care units. The complexity of the septic syndrome comprises immunological aspects- i.e.,sepsis induced immunosuppression- but is not restricted to this fact in modern concepts. So far, exact mechanisms and variables determining outcome and mortality stay unclear. Since there is no typical risk profile, early diagnosis and risk stratification remain difficult, which hinders rapid and effective treatment initiation. Due to the heterogeneous nature of sepsis, potential therapy options should be adapted to the individual. Biomarkers like C-reactive protein and procalcitonin are routinely used as complementary tools in clinical decision-making. Beyond the acute phase proteins, a wide bunch of promising substances and non-laboratory tools with potential diagnostic and prognostic value is under intensive investigation. So far, clinical decision just based on biomarker assessment is not yet feasible. However, biomarkers should be considered as a complementary approach.
文摘背景与目的近年来肺癌发病率和死亡率不断上升,已成为我国恶性肿瘤的首位死因。本研究旨在探讨厦门市居民肺癌死亡和减寿的变化趋势,以期为厦门市肺癌综合防治工作提供依据。方法收集整理2005年-2014年厦门市居民肺癌死亡资料计算死亡率、平均减寿年数(average potential life lost,AYLL)、死亡率年均变化百分比等评价指标,用GM(1,1)模型对死亡率和AYLL进行预测。结果 2005年-2014年,厦门市居民肺癌死亡率28.58/10万,年均上升4.86%,男性死亡率是女性的2.90倍;AYLL为7.8年,存在下降趋势。GM(1,1)模型预测值与实际值平均相对误差2.16%-8.83%,预测2015年-2019年肺癌死亡率和AYLL值均有所上升。结论厦门市肺癌死亡率逐年升高,未来肺癌死亡率和人均减寿数都有上升趋势,应重视肺癌的预防控制工作。
文摘目的:应用支持向量机(support vector machine,SVM)构建ICU中急性肾功能损伤(acute kidney injury,AKI)患者住院死亡风险预测模型,并比较其与ICU中常用的简化急性生理评分(the simplified acute physiology scoreⅡ,SAPS-Ⅱ)的预测性能。方法:使用重症监护医学信息市场(medical information mart for intensive careⅢ,MIMIC-Ⅲ)数据库作为数据来源。根据2012年国际改善全球肾脏病预后组织(Kidney Disease:Improving Global Outcomes,KDIGO)发表的《急性肾损伤临床实践指南》选取MIMIC-Ⅲ数据库中的AKI患者,使用SAPS-Ⅱ中所用到的全部变量构建SVM模型,同时,使用MIMIC-Ⅲ数据库定制本地化的SAPS-Ⅱ模型,并比较其与SVM模型的性能优劣。模型性能的评价方法使用五折交叉验证,评价指标使用受试者工作特征曲线下面积(area under the receiver operation characteristic curve,AUROC)、均方根误差(root mean squared error,RMSE)、灵敏度、特异度和准确率。此外,使用Bland-Altman图评估两模型预测结果的一致性。结果:共纳入19 044例AKI患者,死亡率为13.58%。五折交叉验证的结果显示,SVM模型和定制版SAPS-Ⅱ模型的平均AUROC分别为0.86和0.81,差异有统计学意义(t=13.0,P<0.001),SVM模型和定制版SAPS-Ⅱ模型的平均RMSE分别为0.29和0.31,差异有统计学意义(t=-9.6,P<0.001)。在灵敏度和约登指数方面,SVM模型也均优于定制版的SAPS-Ⅱ模型,差异均具有统计学意义(P分别为0.002和<0.001)。Bland-Altman图显示当患者死亡风险极高或者极低时,两模型预测结果的一致性较好。当患者死亡风险的不确定性较大时,两模型预测结果的一致性较差。结论:相比于传统的SAPS-Ⅱ模型,SVM模型的预测性能更优,且当患者的死亡风险不确定时,这种优势尤其明显;SVM模型更有利于AKI患者的死亡风险识别与早期干预,能有效地帮助ICU临床医生提高医疗质量,有很强的临床应用价值。
文摘水库进行水力排沙时,高含沙水流过程可能会对鱼类等水生动物产生负面影响,其量化评估方法研究较为薄弱。为了预测和评估水库排沙过程对下游鱼类的影响,本文利用黄河花斑裸鲤和鲤鱼在高含沙水体中生存特性研究的实验数据,综合考虑含沙量和粒径、溶解氧、暴露时间、水温等因子对鱼类生存的影响,建立了基于IPSO-BP神经网络的高含沙水体对鱼类致死影响预测方法,对目标鱼类死亡率的预测误差小于6%。本文使用了与BP神经网络紧密耦合并引入动态参数和变异扰动的IPSO算法,较BP和PSO-BP神经网络预测能力更佳,相比国内外已有的Stress Index(SI)、Severity of Ill Effect(SEV)和多元拟合方法预测精度得到显著提升。分析表明,本文提出的预测方法能够考虑高含沙水体中鱼类生存受多环境因子联合制约,且多因子之间存在复杂关联的情况,可为评估高含沙水流过程对水生态的影响提供新的方法。
文摘Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure (AHF). Methods 2486 patients who were 60 years and older from intensive care units of Cardiology De- partment in the hospital were analyzed. Independent risk factors for in-hospital mortality were obtained by binary logistic regression and then used to establish the risk prediction score system (RPSS). The area under the curve (AUC) of receiver operator characteristic and C-statistic test were adopted to assess the performance of RPSS and to compare with previous get with the guidelines-heart failure (GWTG-HF). Re- sults By binary logistic regression analysis, heart rate (OR: 1.043, 95% CI: 1.030-1.057, P 〈 0.001), left ventricular ejection fraction (OR: 0.918, 95% CI: 0.833~).966, P 〈 0.001), pH value (OR: 0.001, 95% CI: 0.000-0.002, P 〈 0.001), renal dysfunction (OR: 0.120, 95% CI: 0.066M).220, P 〈 0.001) and NT-pro BNP (OR: 3.463, 95% CI: 1.870-6.413, P 〈 0.001) were independent risk factors of in-hospital mortal- ity for elderly AHF patients. Additionally, RPSS, which was composed of all the above-mentioned parameters, provided a better risk predic- tion than GWTG-THF (AUC: 0.873 vs. 0.818, P = 0.016). Conclusions Our risk prediction model, RPSS, provided a good prediction for in-hospital mortality in elderly patients with A/IF.