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基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II决策方法
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作者 杨威 李静 《工程数学学报》 CSCD 北大核心 2024年第3期525-539,共15页
针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测... 针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测度。然后基于区间毕达哥拉斯犹豫模糊数的模糊因子、直觉因子和幅度因子,给出熵和交叉熵公式,并证明其性质,提出了基于熵和交叉熵确定属性权重的方法。最后提出了区间毕达哥拉斯犹豫模糊环境下的改进的ELECTRE II法,利用综合优势值对方案进行排序,并通过算例和比较分析验证了该方法的可行性和有效性。 展开更多
关键词 多属性决策 区间毕达哥拉斯犹豫模糊集 交叉熵 ELECTRE ii
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融合NSGA-II和CSA的多目标车间调度
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作者 杨青 席珍珍 +2 位作者 葛亮 林星宇 邢志超 《计算机工程与应用》 CSCD 北大核心 2024年第4期315-323,共9页
针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-do... 针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-dominated sorting genetic algorithms)和克隆选择(clonal selection algorithm,CSA)的改进算法INGCSA来解决此类问题。采用工件、加工机台和AGV三部分编码;引入非支配排序和目标函数值大小排序后总得分进行种群分层,从而有效地保留优秀个体;针对克隆后的种群,对不同等级的种群采取不同的变异概率,并对染色体进行内部交换与均匀交叉混合交换的基因重组,有效地提高了种群的多样性与防止陷入局部最优。通过三组对比实验,验证了该算法在探索最优解时,具有运行时间短、稳定性高和收敛性好等优点。 展开更多
关键词 NSGA-ii 克隆选择算法 任务调度 运输调度 自动引导车(AGV)
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基于改进NSGA-II的轨道交通接驳公交线路优化
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作者 裴玉龙 姜封帅 +1 位作者 王婉佼 何庆龄 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期54-63,共10页
为解决接驳公交线路规划不合理和时间安排不完善的问题,提出了基于改进NSGA-II算法的环形接驳公交线路优化方法。首先,结合双层规划理论,以乘客出行时间成本最小化、公交企业运营收益和接驳公交服务率最大化为目标函数,以接驳公交线路... 为解决接驳公交线路规划不合理和时间安排不完善的问题,提出了基于改进NSGA-II算法的环形接驳公交线路优化方法。首先,结合双层规划理论,以乘客出行时间成本最小化、公交企业运营收益和接驳公交服务率最大化为目标函数,以接驳公交线路站点数、线路长度和发车频率作为约束条件构建上层模型,采用Logit模型构建了下层接驳客流分配模型;其次,运用Floyd算法对NSGA-II算法的初始化种群进行了优化,针对所提出的模型设计了模型求解流程;最后,以哈尔滨市轨道交通1号线医大一院轨道交通站为案例,运用笔者提出的多目标双层规划模型和算法进行求解,并与原NSGA-II算法和基于Logistic混沌映射的NSGA-II算法进行对比。研究结果表明:基于Floyd算法改进的NSGA-II算法在多目标双层规划模型求解时,收敛速度更快效果更好,求解结果可以在Pareto前沿得到多个相互非支配的最优解;不同解集对应目标函数值不同,但可以达到接驳公交网络整体效益最优,采用折衷最优解集表述求解结果。 展开更多
关键词 交通工程 城市公交 多目标优化 双层规划 NSGA-ii
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营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II水平和心功能的影响
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作者 王静 李燕妮 《临床医学进展》 2024年第1期1135-1140,共6页
目的:观察营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II (AngII)水平和心功能的影响。方法:将128例患者分为两组,对照组64例,治疗组64例。对照组予常规治疗,治疗组患者在此基础上加用营心宁胶囊治疗,每次4粒,每日3次。治疗前及... 目的:观察营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II (AngII)水平和心功能的影响。方法:将128例患者分为两组,对照组64例,治疗组64例。对照组予常规治疗,治疗组患者在此基础上加用营心宁胶囊治疗,每次4粒,每日3次。治疗前及治疗8周后检测血浆AngII、脑钠肽(BNP),并行心脏彩色多普勒超声心动图测定左室射血分数(LVEF)、左室舒张末期内径(LVEDD)和每搏输出量(SV)。结果:治疗组和对照组总有效率分别为92.2%和89.1% (P > 0.01);显效率分别为43.8%,32.8% (P < 0.01)。两组治疗后患者的AngII、BNP、LVEF、LVEDD和SV均较治疗前明显改善(P < 0.01或P < 0.05),且治疗组患者的改善水平优于对照组(P < 0.01)。结论:营心宁胶囊能有效降低患者AngII水平,并对心功能有改善作用。 展开更多
关键词 营心宁 冠状动脉粥样硬化性心脏病心力衰竭 血管紧张肽ii 心功能
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血管紧张素II对脓毒症休克大鼠心脏功能的影响
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作者 安辉 姜檀 李晓伟 《中文科技期刊数据库(文摘版)医药卫生》 2024年第4期0182-0185,共4页
本研究拟通过盲肠结扎穿孔制备大鼠脓毒症模型,观察血管紧张素II对脓毒症休克(sepsis-shock)大鼠心脏功能的影响。方法 48只(Sprague-Dawley,SD)雄性大鼠随机分为6组(n=8):对照(control)组、假手术(sham)组、脓毒症休克(SS)组、去甲肾... 本研究拟通过盲肠结扎穿孔制备大鼠脓毒症模型,观察血管紧张素II对脓毒症休克(sepsis-shock)大鼠心脏功能的影响。方法 48只(Sprague-Dawley,SD)雄性大鼠随机分为6组(n=8):对照(control)组、假手术(sham)组、脓毒症休克(SS)组、去甲肾上腺素(NE)治疗组、血管紧张素II (ANGII)治疗组。采用盲肠结扎穿孔制备脓毒症休克动物模型。监测大鼠心率、血压变化。监测过程中大鼠如出现平均动脉压下降至65mmHg以下,立即给予0.9%生理盐水进行液体复苏,观察10分钟后如效果不佳,按照分组给予不同血管活性药物泵入。分别在造模后6,12,18,24小时抽血行心肌酶学指标检测,同时在该时段行超声观察大鼠心脏超声检查。于术后24小时留取心脏组织进行氧化因子指标测定,并进行心脏组织病理学观察。结果 与对照组和假手术组对比,脓毒症休克、去甲肾上腺素组、血管紧张素组平均动脉压下降明显,液体复苏效果欠佳,需要血管活性药物干预。与对照组和假手术组对比,脓毒症休克、去甲肾上腺素组、血管紧张素II组炎症反应、乳酸指标明显升高,具有统计学差异(P<0.05)。脓毒症休克组与对照组、假手术组相比,心脏左室射血分数(LVEF)明显下降,具有统计学差异(P<0.05),应用血管活性药物后,左室射血分数明显提高,血管紧张素II组射血分数提高与脓毒症组相比,具有显著统计学差异(P<0.01)。脓毒症休克组与对照组、假手术组相比,心肌酶学指标明显升高,应用去甲肾上腺素或血管紧张素II干预后,心肌酶学指标下降,与脓毒症组相比,具有统计学差异(P<0.05),血管紧张素II组改善更为明显(P<0.01)。结论 血管紧张素II可改善脓毒症休克对大鼠的心肌损害,对脓毒症休克大鼠心肌有一定的保护作用。 展开更多
关键词 脓毒症休克 去甲肾上腺素 血管紧张素ii 心脏功能
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表达Strep-tag II的重组塞内卡病毒的构建与鉴定
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作者 史家宝 蒙靓 +4 位作者 肖培宇 范峻豪 安同庆 王海伟 于力 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第2期140-146,共7页
为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测... 为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测序鉴定正确后,将p SVA-Strep转染BHK-21细胞拯救重组病毒,收集病变细胞上清,并将含有病毒的细胞上清和野生型SVA(SVA-WT)分别感染BHK-21细胞,以未感染病毒的BHK-21细胞作为阴性对照,感染后24 h分别以鼠源SVA VP2蛋白单克隆抗体(MAb)5D10(1∶1000)、鼠源Strep-tag II MAb(1∶2000)作为一抗,以FITC标记的山羊抗小鼠Ig G(1∶2000)为二抗,采用间接免疫荧光试验(IFA)对重组病毒鉴定。IFA结果显示,以鼠源SVA VP2蛋白MAb 5D10为一抗,SVA-WT和重组病毒感染的细胞均出现绿色荧光,以Strep-tag II MAb作为一抗时,仅有重组病毒感染的细胞出现绿色荧光,经SVA-WT感染的BHK-21细胞及阴性对照细胞均无绿色荧光,表明拯救了Strep-tag II标记的重组病毒,并将其命名为r SVA-Strep。将r SVA-Strep在BHK-21细胞中连续传10代,每隔2代采用引物VP1-F/R经PCR鉴定并对第10代重组病毒的VP1基因测序以鉴定r SVA-Strep的遗传稳定性。结果显示,每隔两代的重组病毒经PCR扩增后均出现约780 bp的目的条带,第10代重组病毒扩增的VP1基因测序结果显示Strep-tag II基因仍在重组病毒中,且无基因突变,表明r SVA-Strep的遗传稳定性较强;将SVA-WT和r SVA-Strep分别以MOI 0.01感染BHK-21细胞,在感染后4 h、8 h、12 h、24 h、36 h、48 h和72 h收获病毒测定病毒滴度并绘制生长曲线,结果显示在病毒感染36 h内r SVA-Strep和SVA-WT生长动力学基本一致,表明Strep-tag II的引入在病毒感染36 h内对SVA的复制基本无影响。采用0.2%甲醛充分灭活r SVA-Strep,并利用Strep-TactinRXT Purification纯化试剂盒纯化该灭活病毒,将r SVA-Strep灭活病毒上清加至Strep-Tactin亲和层析柱,分别用不同体积洗脱缓冲液依次洗脱病毒并通过western blot鉴定病毒的纯化效果。对纯化过程中不同洗脱液洗脱病毒的western blot结果显示,不同体积的洗脱液中E1、E2和E3均出现VP0和VP2两条带,且E1和E2的条带最明显,表明洗脱缓冲液的最佳洗脱体积约为2.2 CV;以上结果表明r SVA-Strep可通过Strep-Tactin亲和层析柱一步法纯化。本研究在SVA中插入Strep-tag II标签,为SVA灭活疫苗的快速纯化提供技术手段,也为其他病原的快速纯化方法的建立提供参考。 展开更多
关键词 塞内卡病毒 Strep-tag ii 感染性克隆 抗原纯化
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基于NSGA-II遗传算法的定轴注射模具成型工艺参数优化
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作者 陈超 高全杰 《农业装备与车辆工程》 2024年第8期153-157,共5页
为解决注射成型过程中铸件的质量和铸造效率低等问题,提出一种NSGA-II算法和TOPSIS方法与响应面法相结合的新型注射工艺参数优化筛选方法。以定轴为研究对象,采用Box-Behnken设计,以熔体温度、模具温度、注射时间、保压压力为变量,以翘... 为解决注射成型过程中铸件的质量和铸造效率低等问题,提出一种NSGA-II算法和TOPSIS方法与响应面法相结合的新型注射工艺参数优化筛选方法。以定轴为研究对象,采用Box-Behnken设计,以熔体温度、模具温度、注射时间、保压压力为变量,以翘曲变形量和体积收缩率为响应变量,采用NSGA-II遗传算法对2个响应的目标函数执行优化,用TOPSIS方法求解优化得到的Pareto前沿解集,找到最优解。仿真结果表明,当注射时间为40.71s、模具温度为131℃、熔体温度为180.07℃、保压压力为65 MPa时,翘曲变形降低了10.92%、体积收缩率降低了11.19%。优化后的注射工艺参数可有效消除铸件内部收缩松动和缩孔缺陷,形成性能良好的致密铸件,提高了产品质量。 展开更多
关键词 注射成型 多目标优化 BOX-BEHNKEN设计 NSGA-ii遗传算法
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Fe(II)改性蒙脱石对土壤汞的吸附固定机理探究
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作者 周细霞 刘朝淑 孙荣国 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第4期63-74,共12页
为明确Fe-MMT对土壤汞离子(Hg^(2+))的吸附、解吸特性及潜在作用机理,采用FeSO_(4)·7H_(2)O改性钠基蒙脱土(Na-MMT),合成了Fe(II)基蒙脱石(Fe-MMT),并探究了不同pH值、吸附剂用量、Hg^(2+)初始浓度和反应时间等条件下,Fe-MMT对土壤... 为明确Fe-MMT对土壤汞离子(Hg^(2+))的吸附、解吸特性及潜在作用机理,采用FeSO_(4)·7H_(2)O改性钠基蒙脱土(Na-MMT),合成了Fe(II)基蒙脱石(Fe-MMT),并探究了不同pH值、吸附剂用量、Hg^(2+)初始浓度和反应时间等条件下,Fe-MMT对土壤Hg^(2+)的吸附解吸特性、吸附动力学和等温吸附模型。结果发现:在pH=5、吸附剂用量为0.5 g、Hg^(2+)初始浓度为170 mg/L、反应时间为0.5 h的条件下,Fe-MMT对土壤Hg^(2+)的去除率高达76.8%;Fe-MMT对Hg^(2+)+的吸附过程符合Langmuir等温吸附模型,伪二阶动力学模型可较好地拟合吸附动力学行为,表明该吸附过程主要为单分子层吸附,且主要发生在吸附剂表面的均相反应位点上;结合微观结构表征,发现Fe-MMT对土壤Hg^(2+)的吸附主要通过-S^(2-)、-SH和-OH与Hg^(2+)进行络合,以及Fe^(2+)与Hg^(2+)的原位共沉淀络合引起的;Fe-MMT在水-土混合体系中的解吸率为9.7%,表明Fe-MMT对土壤Hg^(2+)具有较强的固定作用。可见,Fe-MMT具有修复Hg污染土壤的潜力。 展开更多
关键词 吸附 水土混合 解吸 Fe(ii)改性蒙脱石(Fe-MMT)
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Causal Analysis Between Rice Growth and Cadmium Accumulation and Transfer under Arbuscular Mycorrhizal Inoculation 被引量:2
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作者 ZHAO Ting WANG Li +1 位作者 YANG Jixian MA Fang 《Rice science》 SCIE CSCD 2024年第2期226-236,共11页
Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The r... Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF. 展开更多
关键词 cadmium transfer dilution effect heavy metal immobilization mycorrhizal effect path analysis phenotypic plasticity
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成人低角型安氏II类1分类与安氏II类2分类错合畸形矫治前唇颏形态差异性研究
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作者 吴金枝 姜荻 +1 位作者 蒋均红 刘新庆 《中文科技期刊数据库(文摘版)医药卫生》 2024年第10期0116-0119,共4页
通过对比成人低角型安氏II类1分类和安氏II类2分类错合畸形患者的面部形态特点及唇颏形态,为临床制定矫治方案和临床治疗工作提供思路。方法 分别选取低角型安氏I类1分类和安氏II类2分类错合畸形患者40例,男女比例为1:1,年龄:18-25岁.... 通过对比成人低角型安氏II类1分类和安氏II类2分类错合畸形患者的面部形态特点及唇颏形态,为临床制定矫治方案和临床治疗工作提供思路。方法 分别选取低角型安氏I类1分类和安氏II类2分类错合畸形患者40例,男女比例为1:1,年龄:18-25岁.通过将侧貌X线片和面部90°面相重合,对测量面部软组织21项指标进行测量。结果 上唇突点—E线距离,下唇突点—E线距离,上唇倾角,下唇倾角,上唇厚度,上下唇面积对比均有统计学意义(P<0.05)。结论 低角型安氏II类1分类与安氏II类2分类相比,上下唇均呈前突状,上唇面积,安氏II类1分类较安氏II类2分类小,下唇面积,安氏II类1分类较安氏II类2分类大。 展开更多
关键词 低角型 安氏ii类1分类 安氏ii类2分类 唇颏形态
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青霜露暴露治疗II度烧烫伤临床观察
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作者 陈建彬 丁祖章 +3 位作者 陈骏 宋红梅 刘莹莹 胡娟 《外科(汉斯)》 2024年第3期55-61,共7页
目的:观察青霜露暴露治疗烧烫伤的临床效果。方法:门诊II度烧烫伤患者100例,其中浅II度67例,深II度33例。以暴露疗法在烧烫伤创面青霜露局部用药,每日1~3次,直至愈合。结果:67例浅II度烧烫伤创面经青霜露治疗全部愈合,愈合时间最短6天,... 目的:观察青霜露暴露治疗烧烫伤的临床效果。方法:门诊II度烧烫伤患者100例,其中浅II度67例,深II度33例。以暴露疗法在烧烫伤创面青霜露局部用药,每日1~3次,直至愈合。结果:67例浅II度烧烫伤创面经青霜露治疗全部愈合,愈合时间最短6天,最长30天;33例深II度烧烫伤创面经青霜露治疗30天痊愈31例,显效2例,愈合时间最短14天。所有创面愈合良好,局部疼痛消失和无明显增生性瘢痕。结论:青霜露治疗烧烫伤促进创面愈合,疗效确切;本方法简单方便,值得临床推广应用。 展开更多
关键词 青霜露 暴露疗法 ii度烧烫伤 临床观察
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Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature 被引量:1
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作者 Tong Lu Li Mei +2 位作者 Bao-Chao Li Zi-Wei Huang Huang Li 《World Journal of Clinical Cases》 SCIE 2024年第2期431-442,共12页
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or... BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases. 展开更多
关键词 Temporomandibular disorder Skeletal class ii Deep overbite Dual bite Invisible mandibular advancement appliance Case report
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血管活性药物评分联合APACHE II评分对血流感染后脓毒性休克患者预后的预测价值
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作者 王佳权 姚莉 赵晶晶 《临床医学进展》 2024年第2期3114-3121,共8页
目的:探讨血管活性药物评分(vasoactive inotropic score, VIS)联合急性生理与慢性健康评分(APACHE II)对血流感染后脓毒性休克患者结局的预测价值,为临床提供参考。方法:采用回顾性研究方法,通过收集2020年1月至2022年12月安徽医科大... 目的:探讨血管活性药物评分(vasoactive inotropic score, VIS)联合急性生理与慢性健康评分(APACHE II)对血流感染后脓毒性休克患者结局的预测价值,为临床提供参考。方法:采用回顾性研究方法,通过收集2020年1月至2022年12月安徽医科大学附属合肥医院重症医学科收治的185例脓毒性休克患者的临床资料,根据28 d转归情况,分为存活组95例和死亡组90例,记录所有患者性别、年龄、相关血液检测指标、SOFA评分、24小时内急性生理与慢性健康评分(APACHE II)及24小时内最大血管活性药物评分(VISmax24)等信息,采用单因素分析筛选脓毒性休克患者的相关危险因素,多因素logistic回归分析影响脓毒性休克患者预后的独立危险因素,采用受试者工作特征(receiver op-erating characteristic, ROC)曲线下面积(area under curve, AUC)分析各指标的诊断价值。结果:单因素分析结果表明:死亡组的APACHE II评分(24.30 ± 5.157)、VISmax24 [100.0 (53.5, 121.0)]明显高于存活组(P max24联合APACHE II评分(AUC = 0.848, 95% CI: 0.792~0.905),较单一的APACHE II评分(AUC = 0.729, 95% CI: 0.655~0.802)、VISmax24 (AUC = 0.783, 95% CI: 0.709~0.856)、乳酸(AUC = 0.665, 95% CI: 0.587~0.743)、SOFA (AUC = 0.680, 95% CI: 0.602~0.758)预测价值更高。结论:VISmax24联合APACHE II评分能更有效预测血流感染后脓毒性休克患者的预后。 展开更多
关键词 血管活性药物评分 脓毒性休克 APACHE ii评分 病死率 预测价值
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Putrescine Modulates Cadmium Fixation Ability of Cell Wall to Decrease Cadmium Accumulation in Rice,a Process Might Depend on Nitric Oxide
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作者 WANG Haoyu LI Su +4 位作者 YANG Jibo HUANG Jing ZHU Xiaofang SHEN Renfang ZENG Dali 《Rice science》 SCIE CSCD 2024年第3期237-240,I0002-I0007,共10页
Although putrescine(PUT)has been linked to plants'responses to cadmium(Cd)stress,the exact mechanism is still elusive.In the current investigation,the endogenous PUT concentration in rice roots was enhanced by Cd ... Although putrescine(PUT)has been linked to plants'responses to cadmium(Cd)stress,the exact mechanism is still elusive.In the current investigation,the endogenous PUT concentration in rice roots was enhanced by Cd stress.Exogenous PUT increased root cell wall hemicellulose levels,which in turn increased its Cd binding capacity,concurrently decreasing the transcription level of genes such as OsNRAMP1 and OsCd1 that are responsible for root Cd absorption.As a result。 展开更多
关键词 absorption ROOTS cadmium
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Metallothionein 1E Alleviates Cadmium-induced Renal Cytotoxicity through Promoting Mitochondrial Functional Recovery
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作者 WEN Si Hui LI Lu Bei +2 位作者 HUANG Hui Dan XIE Ying LUO Lei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第1期117-121,共5页
The pervasive utilization of industrial substances has escalated human exposure to cadmium(Cd),a metal associated with long-term negative health outcomes such as renal dysfunction,neurological disorders,and various ca... The pervasive utilization of industrial substances has escalated human exposure to cadmium(Cd),a metal associated with long-term negative health outcomes such as renal dysfunction,neurological disorders,and various cancers^([1]).Once ingested by humans,Cd interacts with cysteine-rich metallothioneins(MTs)which have metal-binding and antioxidant properties and is subsequently transported to the kidney^([2]). 展开更多
关键词 RENAL KIDNEY cadmium
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Combined Effect of Temperature and Cadmium on Molecular Responses of Hsp70 and P-gp Genes in Crassostrea gigas
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作者 HU Fanguang SUN Ming +3 位作者 LIU Guangbin JING Yuanyuan CHEN Qun ZHANG Tianwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1115-1120,共6页
To evaluate the combined effect of temperature and cadmium on the molecular responses of heat shock protein 70(hsp70)and P-glycoprotein(P-gp)in mantle,digestive gland and gills of Crassostrea gigas,oysters were expose... To evaluate the combined effect of temperature and cadmium on the molecular responses of heat shock protein 70(hsp70)and P-glycoprotein(P-gp)in mantle,digestive gland and gills of Crassostrea gigas,oysters were exposed to combinations of five temperature levels(10,15,20,25,and 30℃)and 10μg L^(-1)cadmium for 21 days.Oysters were sampled for mRNA quantification by qPCR,and the results showed that the P-gp gene expression changed significantly after treatment at different temperatures and different treatment times.The P-gp gene expression was the highest in the digestive gland.Compared with the control group,the P-gp gene expression in cadmium treatment groups at all the different temperatures were significantly higher than the control group.The control oysters(kept at 10℃during the whole experiment without cadmium)expressed low levels of hsp70,but the groups treated with cadmium displayed somewhat higher levels.The present study demonstrated hsp70 and P-gp played an important role in the detoxification of Cd in C.gigas,and confirmed temperature should be considered for the assessment of Cd-induced toxicity in oysters. 展开更多
关键词 temperature cadmium P-GP HSP70 Crassostrea gigas
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Appropriate Supply of Ammonium Nitrogen and Ammonium Nitrate Reduces Cadmium Content in Rice Seedlings by Inhibiting Cadmium Uptake and Transport
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作者 HU Yunchao YAN Tiancai +13 位作者 GAO Zhenyu WANG Tiankang LU Xueli YANG Long SHEN Lan ZHANG Qiang HU Jiang REN Deyong ZHANG Guangheng ZHU Li LI Li ZENG Dali QIAN Qian LI Qing 《Rice science》 SCIE CSCD 2024年第5期587-602,I0062-I0064,共19页
Reasonable nitrogen(N) application is a promising strategy for reducing crop cadmium(Cd) toxicity. However, the specific form of N and the required amount that affect Cd tolerance and accumulation in rice remain uncle... Reasonable nitrogen(N) application is a promising strategy for reducing crop cadmium(Cd) toxicity. However, the specific form of N and the required amount that affect Cd tolerance and accumulation in rice remain unclear. This study explored the influence of different N-fertilizer forms(NH_(4)NO_(3), NH_4Cl, and KNO_(3)) and dosages on Cd tolerance and uptake in Cd-stressed N-sensitive and N-insensitive indica rice accessions. The results indicated that the Cd tolerance of N-sensitive indica accessions is more robust than that of N-insensitive ones. Furthermore, the shoot Cd content and Cd translocation rate in both N-sensitive and N-insensitive indica accessions decreased with an appropriate supply of NH_(4)NO_(3) and NH_4Cl, whereas they were comparable or slightly increased with increased KNO_(3). Unfortunately, we did not find significant and regular differences in Cd accumulation or translocation between N-sensitive and N-insensitive rice accessions. Consistent with the reduction of shoot Cd content, the addition of NH_(4)NO_(3) and NH_4Cl also inhibited the instantaneous root Cd^(2+) uptake. The expression changes of Cd transport-related genes under different N forms and dosages suggested that the decreased shoot Cd content, caused by the increased supply of NH_(4)NO_(3) and NH_4Cl, is likely achieved by reducing the transcription of OsNRAMP1 and OsIRT1. In summary, our findings reveal that an appropriate supply of NH_(4)NO_(3) and NH_4Cl could reduce Cd uptake and transport in rice seedlings, suggesting that rational N management could reduce the Cd risk in rice production. 展开更多
关键词 Oryza sativa cadmium nitrogen ammonium nitrate ammonium chloride
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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 Yong Yang Yan Deng Yizhong Yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution cadmium Spodoptera exigua tissue distribution REPRODUCTION
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2-萘甲酸/1,10-菲啰啉共同构筑Mn(II)配合物的合成及固态发光
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作者 任娜娜 江旭滢 +3 位作者 宋合兴 史福林 王雅茹 孙赞 《人工晶体学报》 CAS 北大核心 2024年第10期1776-1783,共8页
在溶剂热条件下,以2-萘甲酸(HL)与1,10-菲啰啉(phen)为配体、碳酸锰为金属源合成了一例双核锰配合物[Mn_(2)(L)_(4)(phen)_(2)(H_(2)O)_(2)](1)。通过单晶X射线衍射、元素分析、傅里叶变换红外光谱、粉末X射线衍射和热重分析等对配合物... 在溶剂热条件下,以2-萘甲酸(HL)与1,10-菲啰啉(phen)为配体、碳酸锰为金属源合成了一例双核锰配合物[Mn_(2)(L)_(4)(phen)_(2)(H_(2)O)_(2)](1)。通过单晶X射线衍射、元素分析、傅里叶变换红外光谱、粉末X射线衍射和热重分析等对配合物1进行结构表征。单晶衍射分析表明配合物1属于三斜晶系,P1空间群,晶胞参数为a=0.76989(5)nm,b=1.17586(5)nm,c=1.66830(9)nm,α=107.074(5)°,β=96.167(5)°,γ=106.901(5)°。不对称单元由一个锰离子、两个2-萘甲酸根、一个1,10-菲啰啉和一个水分子组成,Mn(II)呈扭曲的八面体构型。两个不对称单元之间通过羧基氧原子桥接形成双核分子,双核结构之间通过π…π堆积作用形成2D超分子结构。荧光光谱分析结果表明:配合物1具有良好的荧光性能,最大发射波长为416 nm(λ_(ex)=302 nm)。热重分析表明配合物1能够稳定到117℃,之后开始失水(失水量为3.18%),脱水之后的结构能稳定到223℃,之后有机骨架开始坍塌。Hirshfeld表面分析研究了分子间的相互作用。 展开更多
关键词 双核Mn(ii)配合物 溶剂热合成 晶体结构 2-萘甲酸 荧光性质 表面分析
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Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.
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作者 LIANG Xue-lian CHEN Wei +7 位作者 JIANG Wen-yan LIAO Jie YANG Yu-xia WANG Hai-jun LI Hui-ling LU Wei-fan WANG Tian-shun XIE Hong-zhao 《南方农业学报》 CAS CSCD 北大核心 2024年第8期2386-2395,共10页
【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechan... 【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechanism of A.subulatus Michx.【Method】After cultured for 24 d under the action of Hoagland nutrient solution and gradient Cd concentrations(0,30,60 and 90 mg/L),A.subulatus Michx.were harvested,and its leaf,stem and root were treated by differential centrifugation,chemical reagent extraction,and digested with graphite digester,respectively,then the Cd content in the root,stem and leaf were determined by atomic absorption spectroscopy.【Result】The experimental results indicated that the bioaccumulation capacity of Cd in A.subulatus Michx.was root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of A.subulatus Michx.were 130.74,78.69 and 56.62 mg/kg(fresh matter),respectively.Most of Cd stored in the cell wall and the soluble fractions of the root and leaf of A.subulatus Michx.,with only a smaller portion Cd in organelle fraction.Analysis result of subcellular Cd content showed that 52.27%-58.61%of Cd for root was mainly stored in the soluble fraction,but 42.10%-63.28%of Cd for leaf was mainly stored in the cell wall fraction.The concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms Cd.Pectates and protein integrated-Cd was the main chemical forms Cd in the root and leaf of A.subulatus Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,respectively.Cd treatment could significantly increase the proportion of water-soluble organic acid Cd from 13.64%to 22.72%in root and undissolved phosphate Cd from 10.02%to 32.78%in leaf with increasing Cd concentration in the culture medium.【Conclusion】The root,stem and leaf of A.subulatus Michx.has strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and less toxic pectates and protein integrated-Cd is the main chemical forms Cd in the root and leaf of A.subulatus Michx.,this might be the main mechanism of Cd tolerance in A.subulatus Michx. 展开更多
关键词 Aster subulatus Michx. cadmium BIOACCUMULATION chemical form subcellular distribution
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