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A NEW REACTIVITY INDEX——PSEUDO ORBITAL INDEX
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作者 Fu Jiang DING Liang Fu ZHANG Guang Nian LI 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期975-978,共4页
The concept of pseudo orbital has been proposed, which includes the interactions of all the orbitals and extends the applicable limit of Fukui's frontier orbitals. An example shows that the pseudo orbital reactivi... The concept of pseudo orbital has been proposed, which includes the interactions of all the orbitals and extends the applicable limit of Fukui's frontier orbitals. An example shows that the pseudo orbital reactivity indexes are probably able to explain more complicated phenomena in chemical reactions. 展开更多
关键词 AO A NEW reactivity index PSEUDO ORBITAL index
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RRI、CAR及SII与重症急性胰腺炎并发急性肾损伤的相关性分析
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作者 何勇 王宇 张艳君 《中国急救复苏与灾害医学杂志》 2024年第9期1202-1205,共4页
目的探讨肾血管阻力指数(RRI)、C-反应蛋白与白蛋白比值(CAR)及全身免疫炎症指数(SII)与重症急性胰腺炎并发急性肾损伤(AKI)的相关性。方法选取2020年7月—2022年8月于本院收治的合并AKI重症急性胰腺炎患者28例(AKI组)和未并发AKI重症... 目的探讨肾血管阻力指数(RRI)、C-反应蛋白与白蛋白比值(CAR)及全身免疫炎症指数(SII)与重症急性胰腺炎并发急性肾损伤(AKI)的相关性。方法选取2020年7月—2022年8月于本院收治的合并AKI重症急性胰腺炎患者28例(AKI组)和未并发AKI重症急性胰腺炎患者64例(非AKI组),共计92例重症急性胰腺炎患者作为研究对象,并设立为观察组,同期选取46例健康体检者设立为对照组,对比RRI、CAR及SII指标。采用Logistic回归模型分析重症急性胰腺炎并发AKI的危险因素,并用ROC曲线模型评估RRI、CAR、SII预测AKI的AUC、敏感度、特异度。结果观察组RRI、CAR及SII均高于对照组,差异具有统计学意义(P<0.05)。AKI组RRI、CAR及SII均高于非AKI组,差异具有统计学意义(P<0.05)。Logistic回归模型分析显示,RRI、CAR、SII水平升高会对重症急性胰腺炎患者并发AKI产生影响因素,差异具有统计学意义(P<0.05)。受试者工作特征(ROC)曲线分析显示,RRI、CAR、SII及三项联合预测重症急性胰腺炎患者并发AKI的曲线下面积(AUC)分别为0.789、0.813、0.823、0.907(P<0.05),敏感度分别为57.10%、50.00%、64.30%、92.90%;特异度分别为98.40%、95.30%、90.60%、84.40%。结论RRI、CAR及SII在重症急性胰腺炎患者并发AKI中呈升高趋势,检测其变化可为预测AKI的发生提供参考。 展开更多
关键词 肾血管阻力指数 C-反应蛋白与白蛋白比值 全身免疫炎症指数 重症急性胰腺炎 急性肾损伤
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SIRI、SII及HCAR联合检测对重症急性胰腺炎患者并发感染性胰腺坏死的评估价值
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作者 崔军利 尹华强 +2 位作者 倪培源 未波 周川 《分子诊断与治疗杂志》 2024年第9期1631-1634,共4页
目的分析血清全身炎症反应指数(SIRI)、系统免疫炎症指数(SII)及超敏C-反应蛋白/白蛋白比值(HCAR)联合检测对重症急性胰腺炎(SAP)患者并发感染性胰腺坏死(IPN)的评估价值。方法选取2020年9月至2023年9月绵阳市安州区人民医院收治的122例... 目的分析血清全身炎症反应指数(SIRI)、系统免疫炎症指数(SII)及超敏C-反应蛋白/白蛋白比值(HCAR)联合检测对重症急性胰腺炎(SAP)患者并发感染性胰腺坏死(IPN)的评估价值。方法选取2020年9月至2023年9月绵阳市安州区人民医院收治的122例SAP并发IPN患者为病例组(n=122),另选同期90例SAP无并发IPN患者为对照组(n=90)。收集两组患者的一般资料,并检测血清SIRI、SII、HCAR表达;采用多因素Logistic回归分析SAP患者并发IPN的影响因素;绘制ROC曲线分析血清SIRI、SII、HCAR表达对SAP患者并发IPN的预测价值。结果病例组血清SIRI、SII、HCAR表达均高于对照组,差异有统计学意义(t=11.763、13.406、11.119,均P<0.05);多因素Logistic回归分析显示,年龄≥60岁(OR=1.980)、禁食时间>7 d(OR=1948)、血清SIRI高表达(OR=1.921)、SII高表达(OR=2.006)及HCAR高表达(OR=2.063)均是SAP患者并发IPN的独立危险因素(P<0.05);ROC曲线分析显示,血清SIRI、SII、HCAR表达及联合检测的曲线下面积(AUC)分别为0.881、0.907、0.870、0.943,联合检测优于单一检测(P<0.05)。结论SAP并发IPN受到多种因素影响,血清SIRI、SII、HCAR表达对SAP并发IPN有一定评估价值。 展开更多
关键词 重症急性胰腺炎 感染性胰腺坏死 全身炎症反应指数 系统免疫炎症指数 超敏C-反应蛋白/白蛋白比值
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前列腺外周带血流高阻力指数(RI)对前列腺癌的诊断价值 被引量:32
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作者 岳林先 邓立强 +4 位作者 刘军 冉青 陈照祥 潘静 周果 《临床超声医学杂志》 2004年第3期133-135,共3页
目的 探索彩色多普勒超声的血流指标对前列腺癌的诊断价值。方法 采用彩色多普勒双平面直肠腔内探头检测前列腺 ,重点检测前列腺外周带血流参数指标。结果 前列腺增生 67例 ,前列腺癌 5 8例。前列腺外周带血流 2级以上前列腺增生 5 8... 目的 探索彩色多普勒超声的血流指标对前列腺癌的诊断价值。方法 采用彩色多普勒双平面直肠腔内探头检测前列腺 ,重点检测前列腺外周带血流参数指标。结果 前列腺增生 67例 ,前列腺癌 5 8例。前列腺外周带血流 2级以上前列腺增生 5 8% ,前列腺癌 74.13 % ,P <0 .10 ;前列腺增生和前列腺癌的Vmax均值分别是 10 .77cm/s和12 .91cm/s ,RI分别是 0 .71和 0 .82 ,Vmax和RI在两组间有显著统计学差异 (P <0 .0 0 1) ;以RI 0 .75为临界值 ,对前列腺癌诊断的敏感性 87.5 %、特异性 92 .4%、准确性 75 %和阳性预测值 84%。结论 前列腺外周带血流增多 ,RI >0 .75时 ,对前列腺癌的诊断价值明显提高。 展开更多
关键词 前列腺癌 经直肠 彩色多普勒超声 阻力指数
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RI指数联合超声对孕晚期胎儿肾积水预后预测价值的研究 被引量:5
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作者 张子宁 周菊英 《北华大学学报(自然科学版)》 CAS 2015年第3期342-344,共3页
目的探讨RI指数联合超声对孕晚期胎儿肾积水预后预测的价值.方法选取行超声检查发现的晚孕期肾积水胎儿141例,检测胎儿的肾实质厚度、肾盂前后直径(APD)、肾盂肾盏形态,并给予评分,累计3项指标评分分值;对胎儿行超声检查时测定... 目的探讨RI指数联合超声对孕晚期胎儿肾积水预后预测的价值.方法选取行超声检查发现的晚孕期肾积水胎儿141例,检测胎儿的肾实质厚度、肾盂前后直径(APD)、肾盂肾盏形态,并给予评分,累计3项指标评分分值;对胎儿行超声检查时测定积水肾脏肾门位置的RI值.将以上检测结果与胎儿出生后1a内行超声检查和临床诊断结果进行对照研究.结果141例胎儿共有170只。肾积水;出生后1a内行超声检查和临床诊断显示,非病理性肾积水121只,病理性49只.随着超声评分值增加,病理性。肾积水风险越高,其中超声评分≤3分均为非病理性肾积水,评分≥8分均为病理性肾积水.病理性肾积水与非病理性肾积水超声评分之间差异具有显著统计学意义(P〈0.01).超声评分为5分时,为辨别诊断非病理性。肾积水和病理性。肾积水的截断值,特异度为88.61%,灵敏度为95.00%.超声评分≤5分的肾积水胎儿的肾动脉RI值在0.60~0.67,而超声评分〉5分的。肾积水胎儿。肾动脉RI值在0.70~0.78.结论超声评分法联合RI指数评估胎儿肾积水预后客观准确,具有较高实用价值,超声评分5分为诊断胎儿病理性肾积水的最佳截断值. 展开更多
关键词 超声评分法 ri指数 胎儿 肾积水
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基于改进RI方法的文本聚类 被引量:1
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作者 熊玮 白越 +2 位作者 刘爱国 吴洁洁 肖建 《南昌大学学报(理科版)》 CAS 北大核心 2016年第5期426-430,共5页
旨在通过考虑特征词汇的潜在语义和自身的重要性来提高文本聚类效果,研究基于RI方法的文本向量表示方法。首先,对基于RI方法构建的特征词汇随机索引向量中+1和-1向量元素出现位置进行约束,以避免在构建特征词汇上下文向量时可能造成该... 旨在通过考虑特征词汇的潜在语义和自身的重要性来提高文本聚类效果,研究基于RI方法的文本向量表示方法。首先,对基于RI方法构建的特征词汇随机索引向量中+1和-1向量元素出现位置进行约束,以避免在构建特征词汇上下文向量时可能造成该特征词汇潜在语义丢失现象;其次,在生成文本向量时考虑特征词汇自身重要性来改进权值的计算;最后,在测试数据上对基于RI方法的文本向量表示进行聚类效果测试与对比分析,结果表明采用基于RI方法能提高文本聚类效果。 展开更多
关键词 文本聚类 ri方法 特征词汇随机索引向量 特征词汇上下文向量 文本向量
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基于索引调制的RIS辅助SIMO通信系统信号检测算法 被引量:2
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作者 景小荣 马玉丹 +1 位作者 万宇 陈前斌 《电子与信息学报》 EI CSCD 北大核心 2022年第7期2382-2391,共10页
面对未来无线移动通信对通信质量和频谱效率的更高要求,该文融合索引调制(IM)与可重构智能表面(RIS)技术,建立基于IM的RIS辅助单输入多输出(SIMO)通信系统架构,并提出一种基于变分贝叶斯推断(VBI)的信号检测算法。首先,在该系统中,RIS... 面对未来无线移动通信对通信质量和频谱效率的更高要求,该文融合索引调制(IM)与可重构智能表面(RIS)技术,建立基于IM的RIS辅助单输入多输出(SIMO)通信系统架构,并提出一种基于变分贝叶斯推断(VBI)的信号检测算法。首先,在该系统中,RIS单元被划分为若干子块,利用RIS子块的激活状态传递附加信息;接着,利用VBI给出激活RIS子块对应的相移矢量与待检测信号的近似后验分布;最后,利用RIS相移矢量近似后验分布的对数零梯度值结合正交匹配追踪算法(OMP)恢复出索引信息比特,进而利用待检测信号对数零梯度值,恢复出发送信号。同时,从理论上推导了基于IM的RIS辅助SIMO系统平均速率。仿真结果表明,与传统RIS辅助的SIMO通信系统相比,基于IM的RIS辅助SIMO系统具有更高的系统平均速率;并且与现有算法相比,该文算法具有更低的误比特率。 展开更多
关键词 信号检测 可重构智能表面 索引调制 变分贝叶斯推断
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TVCDS与RI指数联合血清CA125、CA199水平检测对卵巢癌患者诊断效能的影响 被引量:8
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作者 王璐 《国际医药卫生导报》 2018年第3期409-412,共4页
目的探究经阴道彩色多普勒超声(TVCDS)与多普勒超声阻力指数(RI指数)联合血清糖类抗原125(CA125)、糖类抗原199(CA199)水平检测对卵巢癌患者诊断效能的影响。方法选取2014年1月至2017年2月本院卵巢癌早期患者44例(A组),卵巢... 目的探究经阴道彩色多普勒超声(TVCDS)与多普勒超声阻力指数(RI指数)联合血清糖类抗原125(CA125)、糖类抗原199(CA199)水平检测对卵巢癌患者诊断效能的影响。方法选取2014年1月至2017年2月本院卵巢癌早期患者44例(A组),卵巢良性肿瘤患者38例(B组),均经术后病理学证实,另选取同期健康体检者40例(C组)。均行TVCDS检查,以化学发光免疫分析法测定血清CA125、CA199水平。比较三组血清CA125、CA199水平及A组、B组TVCDS血流参数[收缩期峰值流速(PSV)、舒张末期流速(EDV)、RI指数1,分析TVCDS(RI)、血清CA125、CA125水平单独及联合诊断早期卵巢癌敏感度、特异度、准确度、漏诊率、误诊率。结果经单因素方差分析,三组间血清CA125、CA199水平比较,差异有统计学意义(P〈0.05),A组血清CA125、CA199水平明显高于B组、C组,差异有统计学意义(P〈0.05);A组PSV、EDV高于B组,RI低于B组,差异具有统计学意义(P〈0.05);联合检测早期卵巢癌敏感度93.18%(41,44)、特异度97.37%(37/38)、准确度95.12%(78/82),均高于TVCDs(RI)、血清CA125、CA199水平单独检测,差异具有统计学意义(P〈0.05);联合检测漏诊率6.82%(3/44)、误诊率2.63%(1/38),均低于TVCDS(RI)、血清CA125、CA199水平单独检测,差异具有统计学意义(P〈0.05)。结论TVCDS与RI指数联合血清CA125、CA199水平检测卵巢癌患者,能及早发现恶性肿瘤,具有较高诊断价值,且能减少漏诊、误诊情况,值得临床推广应用。 展开更多
关键词 TVCDS ri指数 CA125 CA199 卵巢癌 诊断效能
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MRI定量参数评估肠道克罗恩病病变活动性 被引量:5
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作者 周金发 朱建国 +5 位作者 李海歌 张发明 刘斐 周良 翟华俊 曹鹏 《中国医学影像技术》 CSCD 北大核心 2016年第12期1895-1899,共5页
目的探讨MRI定量参数ADC与容积转运常数(K^(trans))评估肠道克罗恩病(CD)病变活动性的应用价值。方法收集50例回盲部单发病灶的CD患者,依次行常规MR、DWI和动态增强MRI(DCE-MRI)扫描,测量ADC和K^(trans)值,同时评估患者Harvey-Bradshow... 目的探讨MRI定量参数ADC与容积转运常数(K^(trans))评估肠道克罗恩病(CD)病变活动性的应用价值。方法收集50例回盲部单发病灶的CD患者,依次行常规MR、DWI和动态增强MRI(DCE-MRI)扫描,测量ADC和K^(trans)值,同时评估患者Harvey-Bradshow指数(HBI)和血清C反应蛋白(CRP)浓度。根据HBI将50例患者分为重度活动组、轻中度活动组及静止组,比较3组间K^(trans)、ADC值的差异;对K^(trans)、ADC值与对应的HBI、CRP行相关性分析。结果 50例CD患者中,静止组16例、轻中度活动组21例、重度活动组13例。3组K^(trans)、ADC值的差异均有统计学意义(P均<0.05),组间两两比较差异均有统计学意义(P均<0.05)。病变肠壁K^(trans)值与HBI呈正相关(r=0.635,P<0.001),与CRP呈正相关(r=0.764,P<0.001);ADC值与HBI呈负相关(r=-0.614,P<0.001),与CRP呈负相关(r=-0.490,P<0.001)。病变肠壁HBI与CRP呈正相关(r=0.755,P<0.001),K^(trans)与ADC值呈负相关(r=-0.348,P=0.013)。结论 MRI定量参数K^(trans)和ADC可反映CD活动状态,且K^(trans)的稳定性和敏感性优于ADC。 展开更多
关键词 克罗恩病 Harvey-Bradshow指数 C反应蛋白 扩散磁共振成像 对比剂 表观扩散系数 容积转运常数
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心电图Morris、Macruz指数与经皮球囊二尖瓣成形术疗效的相关性分析 被引量:1
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作者 彭健 翁昌鸿 +5 位作者 刘伊丽 侯玉清 宾建平 谢志斌 贾满盈 张远慧 《心电学杂志》 1996年第2期79-80,共2页
分析32例经皮球囊二尖瓣成形术(PBMV)前、后的心电图Morris指数(PTFv_1)和Macruz指数(Ⅱ导联P/P-R段比值),探讨心电图对判定PBMV疗效的价值。结果Morris指数术前—0.061±0.005mm·s,术后—0.038±0.003mm·s,Macruz指... 分析32例经皮球囊二尖瓣成形术(PBMV)前、后的心电图Morris指数(PTFv_1)和Macruz指数(Ⅱ导联P/P-R段比值),探讨心电图对判定PBMV疗效的价值。结果Morris指数术前—0.061±0.005mm·s,术后—0.038±0.003mm·s,Macruz指数术前2.54±0.12,术后2.02±0.15,均有极显著性差异(P<0.001)。将两指数分别与多项血流动力学和超声心动图测值比较,术前,后均有较好的相关。认为Morris指数和Macruz指数可作为PBMV后疗效判定及心功能随访的一种可靠而简便的方法。 展开更多
关键词 球囊扩张术 二尖瓣成形 MACRUZ指数 超声心动图
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Low Root Zone Temperature Limits Nutrient Effects on Cucumber Seedling Growth and Induces Adversity Physiological Response 被引量:16
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作者 YAN Qiu-yan DUAN Zeng-qiang +2 位作者 MAO Jing-dong LI Xun DONG Fei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1450-1460,共11页
Effects of root-zone temperatures (RZT) (12℃-RZT and 20℃-RZT) and different N, P, and K nutrient regimes on the growth, reactive oxygen species (ROS), and antioxidant enzyme in cucumber seedlings were investig... Effects of root-zone temperatures (RZT) (12℃-RZT and 20℃-RZT) and different N, P, and K nutrient regimes on the growth, reactive oxygen species (ROS), and antioxidant enzyme in cucumber seedlings were investigated in hydroponics. Strong interactions were observed between RZT and nutrient on the dry weight (P=0.001), root length (P=0.001) and leaf area (P=0.05). Plant dry weights were suppressed at low RZT of 12℃, while higher biomass and growth of cucumber seedlings were produced at elevated RZT of 20℃ under each nutrient treatment. Growth indexes (plant height, internode length, root length, and leaf area) at 12℃-RZT had less difference among nutrient treatments, but greater response was obtained for different nutrients at high RZT. RZT had larger effects (P=0.001) on cucumber seedling growth than nutrients. In addition, N was more effective nutrients to plant growth than P and K under low root temperature to plant growth. Higher hydrogen peroxide (H202), malondialdehyde (MDA), soluble sugar (SS) contents in leaves were observed at 12℃-RZT in all nutrient treatments than those at 20℃-RZT, indicating the chilling adversity damaged to plant growth. In general, antioxidant enzyme had larger response under low root-zone temperature. Superoxide dismutase (SOD) activities were higher in both leaves and roots while peroxidase (POD) and catalase (CAT) showed large different action in leaves and roots at both the two root-zone temperature. 展开更多
关键词 Cucumis sativus L. growth indexes antioxidant enzyme reactive oxygen
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食管癌患者血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指标的变化观察 被引量:4
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作者 周敏杰 李少民 《实用临床医药杂志》 CAS 2017年第3期62-64,共3页
目的分析食管癌患者的血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指标的变化情况。方法选取本院收治的66例食管癌患者为观察组,并选取同时间段的66名体检健康人员为对照组,然后将2组的血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指... 目的分析食管癌患者的血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指标的变化情况。方法选取本院收治的66例食管癌患者为观察组,并选取同时间段的66名体检健康人员为对照组,然后将2组的血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指标进行检测与比较,然后将观察组中不同食管癌分期者的检测指标进行比较。结果观察组的血清IL-2低于对照组,血清NGAL、Hcy、sTNF-RI及IL-6、IL-8、IL-18则均高于对照组,另外食管收缩压、蠕动性收缩比及食管括约肌松弛率低于对照组,且观察组中食管癌分期较高者的变化大于食管癌分期较低的患者,差异均有统计学意义(P<0.05)。结论食管癌患者的血清NGAL、Hcy、sTNF-RI、白介素及食管动力学指标呈现异常的状态,且其检测水平受疾病分期的影响较大。 展开更多
关键词 食管癌 血清 NGAL HCY s TNF-ri 白介素 食管动力学指标
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Association of arterial stiffness with coronary flow reserve in revascularized coronary artery disease patients 被引量:4
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作者 Vlassis Tritakis Stavros Tzortzis +7 位作者 Ignatios Ikonomidis Kleanthi Dima Georgios Pavlidis Paraskevi Trivilou Ioannis Paraskevaidis Giorgos Katsimaglis John Parissis John Lekakis 《World Journal of Cardiology》 CAS 2016年第2期231-239,共9页
AIM: To investigate the association of arterial wave reflection with coronary flow reserve(CFR) in coronary artery disease(CAD) patients after successful revascularization.METHODS: We assessed 70 patients with angiogr... AIM: To investigate the association of arterial wave reflection with coronary flow reserve(CFR) in coronary artery disease(CAD) patients after successful revascularization.METHODS: We assessed 70 patients with angiographically documented CAD who had undergone recent successful revascularization. We measured(1) reactive hyperemia index(RHI) using fingertip peripheral arterial tonometry(RH-PAT Endo-PAT);(2) carotid to femoral pulse wave velocity(PWVc-Complior);(3) augmentation index(AIx), the diastolic area(DAI%) and diastolic reflection area(DRA) of the central aortic pulse wave(Arteriograph);(4) CFR using Doppler echocardiography; and(5) blood levels of lipoprotein-phospholipase A2(LpPLA2).RESULTS: After adjustment for age, sex, blood pressure parameter, lipidemic, diabetic and smoking status, we found that coronary flow reserve was independently related to AIx(b =-0.38, r = 0.009), DAI(b = 0.36, P = 0.014), DRA(b = 0.39, P = 0.005) and RT(b =-0.29,P = 0.026). Additionally, patients with CFR < 2.5 had higher PWVc(11.6 ± 2.3 vs 10.2 ± 1.4 m/s, P = 0.019), SBPc(139.1 ± 17.8 vs 125.2 ± 19.1 mm Hg, P = 0.026), AIx(38.2% ± 14.8% vs 29.4% ± 15.1%, P = 0.011) and lower RHI(1.26 ± 0.28 vs 1.50 ± 0.46, P = 0.012), DAI(44.3% ± 7.9% vs 53.9% ± 6.7%, P = 0.008), DRA(42.2 ± 9.6 vs 51.6 ± 11.4, P = 0.012) and Lp PLA2(268.1 ± 91.9 vs 199.5 ± 78.4 ng/m L, P = 0.002) compared with those with CFR ≥ 2.5. Elevated Lp PLA2 was related with reduced CFR(r =-0.33, P = 0.001), RHI(r =-0.37, P < 0.001) and DRA(r =-0.35, P = 0.001) as well as increased PWVc(r = 0.34, P = 0.012) and AIx(r = 0.34, P = 0.001). CONCLUSION: Abnormal arterial wave reflections are related with impaired coronary flow reserve despite successful revascularization in CAD patients. There is a common inflammatory link between impaired aortic wall properties, endothelial dysfunction and coronary flow impairment in CAD. 展开更多
关键词 LpPLA2 CORONARY ARTERY disease ARTEriAL stiffness CORONARY flow RESERVE Reactive HYPEREMIA index
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Gasification of iron coke and cogasification behavior of iron coke and coke under simulated hydrogen-rich blast furnace condition 被引量:6
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作者 Kai Zhu Zhuming Chen +3 位作者 Shuixin Ye Shuhua Geng Yuwen Zhang Xionggang Lu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第10期1839-1850,共12页
To explore the iron coke application in hydrogen-rich blast furnace,which is an effective method to achieve the purpose of low carbon emissions,the initial gasification temperature of iron coke in CO_(2) and H_(2)O at... To explore the iron coke application in hydrogen-rich blast furnace,which is an effective method to achieve the purpose of low carbon emissions,the initial gasification temperature of iron coke in CO_(2) and H_(2)O atmosphere and its cogasification reaction mechanism with coke were systematically studied.Iron coke was prepared under laboratory conditions,with a 0-7wt%iron ore powder addition.The properties of iron cokes were tested by coke reactivity index(CRI)and coke strength after reaction(CSR),and their phases and morphology were evolution discussed by scanning electron microscopy and X-ray diffraction analysis.The results indicated that the initial gasification temperature of iron coke decreased with the increase in the iron ore powder content under the CO_(2) and H_(2)O_((g))atmosphere.In the 40vol%H_(2)O+60vol%CO_(2) atmosphere,CRI of iron coke with the addition of 3wt%iron ore powder reached 58.7%,and its CSR reached 56.5%.Because of the catalytic action of iron,the reaction capacity of iron coke was greater than that of coke.As iron coke was preferentially gasified,the CRI and CSR of coke were reduced and increased,respectively,when iron coke and coke were cogasified.The results showed that the skeleton function of the coke can be protected by iron coke. 展开更多
关键词 iron coke hydrogen-rich blast furnace coke gasification coke reactivity index coke strength after reaction
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基于RIS 的高度小型化双频微带天线设计 被引量:2
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作者 蒲瑞 刘运林 《通信技术》 2020年第8期1877-1882,共6页
设计了一种同轴馈电的高度小型化双频微带天线。该天线采用RIS结构、Giuseppe Peano分形理论、短路针加载这三种技术来实现高度小型化与双频段特性,并在接地面开槽以等效地引入阻抗匹配元件。通过使用HFSS对天线进行仿真优化,得到了天... 设计了一种同轴馈电的高度小型化双频微带天线。该天线采用RIS结构、Giuseppe Peano分形理论、短路针加载这三种技术来实现高度小型化与双频段特性,并在接地面开槽以等效地引入阻抗匹配元件。通过使用HFSS对天线进行仿真优化,得到了天线尺寸参数。仿真结果表明,天线的工作频段为2.27~2.34 GHz、4.37~4.79 GHz,并且天线在低频段的最大增益可达1.628 dBi,高频段最大增益可达6.9 dBi,辐射性能良好。贴片尺寸仅为10 mm×10 mm,与工作于2.3 GHz的普通贴片天线相比,该天线的贴片尺寸缩减了约69%。该天线不仅可以双频工作,而且贴片尺寸很小。 展开更多
关键词 双频天线 分形理论 微带天线 小型化 电抗性阻抗表面(riS) 短路针
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Combined Effects of A Body Shape Index and Serum C-reactive Protein on Ischemic Stroke Incidence among Mongolians in China 被引量:5
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作者 WANG Guang Li ZHANG Rui +5 位作者 ZHOU Yi Ting WANG Ai Li XU Tian ZHANG Ming Zhi LI Hong Mei ZHANG Yong Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第3期169-176,共8页
Objective We aimed to evaluate the combined effects of a high body shape index(ABSI) and a high serum C-reactive protein(CRP) level on the incidence of ischemic stroke in a Mongolian population in China. Methods A pro... Objective We aimed to evaluate the combined effects of a high body shape index(ABSI) and a high serum C-reactive protein(CRP) level on the incidence of ischemic stroke in a Mongolian population in China. Methods A prospective cohort study was conducted among 2,589 participants from June 2002 to July 2012 in Inner Mongolia, China. The participants were categorized into 4 groups according to their level of ABSI and CRP. Cox proportional hazards models were used to assess the hazard ratios(HRs) and 95% confidence intervals(CIs) for ischemic stroke among all groups. Results The multivariate adjusted HRs(95% CI) of ischemic stroke for high ABSI and high CRP level were 1.46(0.89-2.39) and 1.63(0.95-2.79), respectively. Compared with the low ABSI/low CRP level group, the multivariate adjusted HRs(95% CI) of ischemic stroke in the low ABSI/high CRP, high ABSI/low CRP, and high ABSI/high CRP groups were 1.04(0.46-2.35), 1.06(0.58-1.95) and 2.52(1.27-5.00), respectively. The HR of ischemic stroke for the high ABSI/high CRP level group was the highest and most statistically significant. Conclusion We found that participants with simultaneously high ABSI and high CRP levels had the highest risk of ischemic stroke in the Mongolian population. Our findings suggest that the combination of high ABSI and high CRP levels may increase the risk of ischemic stroke. 展开更多
关键词 A body shape index C-reactive protein ISCHEMIC STROKE
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Changes in pulse pressure × heart rate, hs-CRP, and arterial stiffness progression in the Chinese general population: a cohort study involving 3978 employees of the Kailuan Company 被引量:4
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作者 Hao XUE Jun-Juan LI +4 位作者 Jian-Li WANG Shuo-Hua CHEN Jing-Sheng GAO Yun-Dai CHEN Shou-Ling WU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第9期710-716,共7页
Background Pulse wave velocity(PWV) is a marker of arterial stiffness, which represents sub-clinical atherosclerosis. Pulsatile stress and high-sensitivity C-reactive protein(hs-CRP) are associated with arterioscleros... Background Pulse wave velocity(PWV) is a marker of arterial stiffness, which represents sub-clinical atherosclerosis. Pulsatile stress and high-sensitivity C-reactive protein(hs-CRP) are associated with arteriosclerosis. However, there is no prospective data confirming whether changes in pulsatile stress and inflammatory markers affect the progression of arterial stiffness. The aim of this study was to investigate the relationships over time between the effects of changes in pulsatile stress and hs-CRP, and arterial stiffness progression during a 2-year follow-up. Methods We performed a longitudinal study involving 3978 participants. All participants underwent a physical examination in 2010–2011 and 2012–2013, during which we measured participants’ hs-CRP levels, brachial–ankle pulse wave velocity(ba PWV), and pulsatile stress. Results Baseline hs-CRP was correlated with ba PWV(r = 0.18, P = 0.000);however the correlation was weaker than that with systolic blood pressure(r = 0.65), pulsatile stress(r = 0.57), and rate-pressure product(r = 0.58). Multiple linear regression analysis demonstrated that changes in pulsatile stress, mean arterial pressure, and low-density lipoprotein-C(LDL-C) were positively correlated with changes in ba PWV, with correlation coefficients of 0.27, 0.25, and 0.07, respectively, but not with changes in hs-CRP. Moreover, each 100-a U increase in pulsatile stress, 1 mm Hg increase in mean blood pressure, and 1 mmol/L increase in LDL-C was associated with a 3 cm/s, 4.78 cm/s, and 17.37 cm/s increase in ba PWV, respectively. Conclusions Pulsatile stress increases are associated with arterial stiffness progression, but that changes in hs-CRP had no effect on arterial stiffness progression. Hs-CRP may simply be a marker of inflammation in arterial stiffness and has no association with arterial stiffness progression. 展开更多
关键词 ATHEROSCLEROSIS Blood VESSELS Brachial–ankle index C-reactive protein Pulse wave velocity
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Bonding and Reactivity in RB-AsR Systems (R = H, F, OH, CH3, CMe3, CF3, SiF3, BO): Substituent Effects 被引量:1
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作者 GHARA Manas CHATTARAJ Pratim K. 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第2期201-207,共7页
Density functional theory-based calculations have been carried out to study the bonding and reactivity in RB-As R(R=H,F,OH,CH3,CMe_3,CF_3,SiF_3,BO)systems.Our calculations demonstrated that all the studied systems ado... Density functional theory-based calculations have been carried out to study the bonding and reactivity in RB-As R(R=H,F,OH,CH3,CMe_3,CF_3,SiF_3,BO)systems.Our calculations demonstrated that all the studied systems adopted bent geometry(DR-B-As≈180°andDB-As-R≈90°or less).The reason for this bending was explained with the help of a valence-orbital model.The potential energy surfaces for three possible isomers of RB-As R systems were also generated,indicating that the RB-As R isomer was more stable than R_2B-As R when R=SiF_3,CMe_3,and H.The B-As bond character was analyzed using natural bond orbital(NBO)and Wiberg bond index(WBI)calculations.The WBI values for B-As bonds in F3Si B-As SiF_3 and HB-As H were 2.254 and 2.209,respectively,indicating that this bond has some triple-bond character in these systems.While the B centers prefer nucleophilic attack,the As centers prefer electrophilic attack. 展开更多
关键词 密度泛函理论 自然键轨道 化学分析 ASR系统
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RIS辅助索引调制协作系统的误码率性能分析
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作者 喻诚皓 仇润鹤 《计算机应用》 CSCD 北大核心 2023年第11期3559-3567,共9页
针对中继协作通信在发射机和接收机之间的直接路径信号较弱,且信噪比(SNR)低的场景,提出一种智能反射面(RIS)辅助解码转发(DF)中继的协作索引调制(IM)系统(RIS-DF-IM)。在该系统中,RIS作为智能接入点(AP)充当源节点和中继节点发射机的... 针对中继协作通信在发射机和接收机之间的直接路径信号较弱,且信噪比(SNR)低的场景,提出一种智能反射面(RIS)辅助解码转发(DF)中继的协作索引调制(IM)系统(RIS-DF-IM)。在该系统中,RIS作为智能接入点(AP)充当源节点和中继节点发射机的一部分,根据发射信息对反射信道进行相位补偿,最大化接收天线的SNR,并对中继和目的节点接收机的多天线进行索引调制,提高系统的频谱效率;同时,利用矩母函数(MGF)法求解所提出的双跳系统误码率(BER)的理论联合界。此外,还提出了一种预贪婪的最大似然简化(SPML)检测器,通过预贪婪减少遍历天线索引数量,以及简化最大似然译码准则式,降低计算复杂度。蒙特卡洛仿真结果表明,在RIS元件数取128且采用空间调制时,RIS-DF-IM与RIS在远端不接入发射机的协作空间调制系统相比,BER降低了约10;与传统的预编码空间调制系统相比,BER大幅降低,约20;SPML检测器相较于最大似然(ML)检测器,BER增加了约1.4,但是计算复杂度减少了一半,实现了BER与复杂度之间的有效平衡。 展开更多
关键词 智能反射面 索引调制 协作通信 检测器 信噪比 误码率
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Association between serum uric acid level and endothelial dysfunction in elderly individuals with untreated mild hypertension
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作者 Guo-Hua ZHU Xi-Peng SUN +3 位作者 Jing LI Rong-Kun LIU Zheng YANG Qi HUA 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第5期264-269,共6页
Background Endothelial dysfunction is the initial stage in atherosclerotic formation and progression and is associated with high serum uric acid(SUA)level.We hypothesized that reactive hyperemia index(RHI),which refle... Background Endothelial dysfunction is the initial stage in atherosclerotic formation and progression and is associated with high serum uric acid(SUA)level.We hypothesized that reactive hyperemia index(RHI),which reflects endothelial function,is associated with SUA levels in elderly individuals with untreated mild hypertension.Methods We recruited 123 patients≥60 years with untreated mild hypertension.The association between SUA level and RHI was analyzed using univariate correlation analysis and multiple regression analysis.The receiver operating characteristic(ROC)curve was performed to validate the cutoff value of SUA that can be used to predict endothelial dysfunction.Results The serum uric acid level significantly increased in the RHI<1.67 group,and this result was still observed in the subgroup of men.RHI was inversely associated with SUA level(P=0.006)and the association was still observed after adjusting for factors,such as age,sex,smoking status,and creatinine level(P=0.014).In the subgroup analysis,a positive association was observed only in men.In the ROC curve analysis,the optimal cutoff values of SUA for predicting endothelial dysfunction was 293.5μmol/L in elderly mild hypertension patients and 287.0μmol/L in men.Conclusion A high SUA level was considered an independent predictor of endothelial dysfunction among elderly individuals,particularly men with untreated mild hypertension. 展开更多
关键词 Endothelial dysfunction HYPERTENSION Reactive hyperemia index Uric acid
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