目的探讨红细胞体积分布宽度(red cell volume distribution width,RDW)对心脏停搏(cardiac arrest,CA)患者预后的评估价值。方法回顾性分析2018年1月至2022年10月湖州市中心医院重症监护室(intensive care unit,ICU)收治的146例CA患者...目的探讨红细胞体积分布宽度(red cell volume distribution width,RDW)对心脏停搏(cardiac arrest,CA)患者预后的评估价值。方法回顾性分析2018年1月至2022年10月湖州市中心医院重症监护室(intensive care unit,ICU)收治的146例CA患者的临床资料,根据ICU住院期间预后将患者分为存活组和死亡组,比较两组患者的临床资料,采用多因素Logistic回归分析影响CA患者预后的危险因素。采用受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)评估RDW对CA患者预后的预测效能。Kaplan-Meier法绘制患者生存曲线。结果共纳入146例CA患者,其中存活49例,死亡97例,死亡率66.44%。死亡组患者的急性生理学和慢性健康状况评价Ⅱ评分、RDW、血钠、丙氨酸转氨酶均显著高于存活组,心肺复苏时间显著长于存活组,ICU住院时间显著短于存活组(P<0.05)。多因素Logistic回归分析结果显示,RDW、心肺复苏时间均是CA患者ICU住院期间死亡的独立危险因素(P<0.05)。ROC曲线结果显示RDW预测CA患者死亡的曲线下面积为0.742,最佳截断值为13.95%,敏感度59.8%,特异性85.7%。低RDW患者的1年累积生存率显著高于高RDW患者(χ^(2)=18.757,P<0.001)。结论RDW是预测CA患者ICU住院期间死亡的独立危险因素。展开更多
The dynamic viscoelastic behavior of polysiloxanes filled with ultrafine SiO 2 has become ever-lasting important due to its unique properties. In present article, the influence of SiO 2 treated with silane coupling ag...The dynamic viscoelastic behavior of polysiloxanes filled with ultrafine SiO 2 has become ever-lasting important due to its unique properties. In present article, the influence of SiO 2 treated with silane coupling agent bis(3-triethoxysilyl)tetrasulfane(TESPT) on dynamic viscoelastic properties of uncured polymethylvinylsiloxane(PMVS)/ultra fine-silica(SiO 2) composites was investigated by using an advanced rheometric expansion system(ARES) under the conditions of temperature 25 ℃, strain(γ) from 0.01% to 100% and frequency(ω) from 0.01 to 100 rad/s. The results reveal that the treated SiO 2 particles leads to the frequency-dependent storage modulus(G′) which approaches linear viscoelastic behavior in the lower frequency region. Based on an examination of the dynamic viscoelastic behavior and TEM observation, we owe these characteristics to improved dispersion of SiO 2 particles in the polymer matrix due to their surface-treatment as compared with the untreated case. On the other hand, dynamic viscoelastic behavior sensitively reflects the dispersion of SiO 2 particles with diameters from 100 to 500 nm, which further evidence the promotion of filler dispersion induced by the incorporation of TESPT.展开更多
文摘The dynamic viscoelastic behavior of polysiloxanes filled with ultrafine SiO 2 has become ever-lasting important due to its unique properties. In present article, the influence of SiO 2 treated with silane coupling agent bis(3-triethoxysilyl)tetrasulfane(TESPT) on dynamic viscoelastic properties of uncured polymethylvinylsiloxane(PMVS)/ultra fine-silica(SiO 2) composites was investigated by using an advanced rheometric expansion system(ARES) under the conditions of temperature 25 ℃, strain(γ) from 0.01% to 100% and frequency(ω) from 0.01 to 100 rad/s. The results reveal that the treated SiO 2 particles leads to the frequency-dependent storage modulus(G′) which approaches linear viscoelastic behavior in the lower frequency region. Based on an examination of the dynamic viscoelastic behavior and TEM observation, we owe these characteristics to improved dispersion of SiO 2 particles in the polymer matrix due to their surface-treatment as compared with the untreated case. On the other hand, dynamic viscoelastic behavior sensitively reflects the dispersion of SiO 2 particles with diameters from 100 to 500 nm, which further evidence the promotion of filler dispersion induced by the incorporation of TESPT.
