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脑铁代谢紊乱为阿尔茨海默病的治疗提供新靶点
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作者 徐永 张雅婷 +4 位作者 李洁 洪钏 张欣韦 高国粉 常彦忠 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2019年第9期858-868,共11页
脑铁稳态对于维持脑的正常发育和控制细胞氧化应激水平具有重要作用.大量研究已显示,脑铁稳态的失衡与阿尔茨海默病(Alzheimer’s disease,AD)的发病存在密切关系,但其机理尚需深入研究.本文结合本实验室的研究结果,总结了脑铁代谢失衡... 脑铁稳态对于维持脑的正常发育和控制细胞氧化应激水平具有重要作用.大量研究已显示,脑铁稳态的失衡与阿尔茨海默病(Alzheimer’s disease,AD)的发病存在密切关系,但其机理尚需深入研究.本文结合本实验室的研究结果,总结了脑铁代谢失衡参与AD病变的研究进展,重点讨论了脑铁增高与AD症状及细胞损伤的关系,及负责铁摄入、储存、释放和调控的几种铁代谢关键分子在AD中的表达变化,并展望了改善脑铁水平、调节铁代谢相关分子平衡、降低氧化应激等方法作为AD治疗策略的前景.本文旨在为今后深入研究脑铁代谢及相关分子在AD病理过程中的作用,开发预防和治疗AD新药物提供参考. 展开更多
关键词 阿尔茨海默病 脑铁代谢 Β-淀粉样蛋白 铁螯合剂
Serum ferritin in neonatal cholestasis:A specific and active molecule or a non-specific bystander marker? 预览
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作者 Behairy El-Sayed Behairy Hatem Abd-Alsattar Konswa +3 位作者 Hanaa Talaat Ahmed Dina Shehata El-Azab Nermin Mohamed Adawy Ahmad Mohamed Sira 《国际肝胆胰疾病杂志:英文版》 SCIE CAS CSCD 2019年第2期173-180,共8页
Background:Serum ferritin(SF)and consequently hepatic iron have long been considered important in liver fibrosis progression.They have been studied in different liver diseases with no previous reports in neonatal chol... Background:Serum ferritin(SF)and consequently hepatic iron have long been considered important in liver fibrosis progression.They have been studied in different liver diseases with no previous reports in neonatal cholestasis(NC).This study aimed to measure SF in different etiologies of NC and investigate its relation to hepatic iron and fibrosis.Methods:SF was measured in 75 infants,including 50 with NC and 25 with sepsis.SF was compared between these two groups.Biochemical parameters,hepatic iron grades,and liver fibrosis and other histopathological characteristics and correlated with SF were assessed in NC group.Finally,a comparison between intrahepatic cholestasis and obstructive etiology was performed.Results:SF was elevated in NC(1598±2405 ng/mL)with no significant difference from those with sepsis(P=0.445).NC and sepsis constituted augmenting factors leading to more elevation of SF(2589±3511 ng/mL).SF was significantly correlated with hepatic iron grades(r=0.536,P<0.0001)and a cut-off value of 803.5 ng/mL can predict higher grades(≥grade 3)of iron deposition with sensitivity of 100%,specificity of 70%and accuracy of 85%.Moreover,SF was significantly higher(P<0.0001)in those with intrahepatic cholestasis(2602±3154 ng/mL)and their prevalent pathological findings of giant cell transformation(P=0.009)and hepatocyte swelling(P=0.023)than those with obstructive etiology(672±566 ng/mL)and their prevalent pathological findings of ductular proliferation(P=0.003)and bile plugs(P=0.002).SF was unrelated to the grade of liver fibrosis(P=0.058).Conclusions:SF is non-specifically elevated in NC,with positive correlation to hepatic iron grades.SF≥803.5 ng/mL can predict higher grades(≥grade 3)of hepatic iron.However,an active role of increased SF and hepatic iron in disease progression remains questionable. 展开更多
关键词 Biliary ATRESIA Liver fibrosis Hepatic IRON grade INTRAHEPATIC CHOLESTASIS IRON
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Using trace elements of magnetite to constrain the origin of the Pingchuan hydrothermal low-Ti magnetite deposit in the Panxi area, SW China
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作者 Yanjun Wang Weiguang Zhu +3 位作者 Hong Zhong Zhongjie Bai Junhua Yao Chong Xu 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第3期376-390,共15页
The Pingchuan iron deposit, located in the Yanyuan region of Sichuan Province, SW China, has an ore reserve of 40 Mt with ~60 wt% Fe. Its genesis is still poorly understood. The Pingchuan iron deposit has a parageneti... The Pingchuan iron deposit, located in the Yanyuan region of Sichuan Province, SW China, has an ore reserve of 40 Mt with ~60 wt% Fe. Its genesis is still poorly understood. The Pingchuan iron deposit has a paragenetic sequence of an early Fe-oxide–Pyrite stage(Ⅰ) and a late Fe-oxide–pyrrhotite stage(Ⅱ). Stage Ⅰ magnetite grains are generally fragmented, euhedral–subhedral, largesized crystals accompanying with slightly postdated pyrite.Stage Ⅱ magnetite grains are mostly unfragmented, anhedral, relatively small-sized grains that co-exist with pyrrhotite. Combined with micro-textural features and previously-obtained geochronological data, we consider that these two stages of iron mineralization in the Pingchuan deposit correspond to the Permian ELIP magmatism and Cenozoic fault activity event. Both the Stage Ⅰ and Ⅱ magnetites are characterized with overall lower contents of trace elements(including Cr, Ti, V, and Ni) than the ELIP magmatic magnetite, which suggests a hydrothermal origin for them.‘‘Skarn-like’’ enrichment in Sn, Mn, and Zn in the Stage Ⅰ magnetite grains indicate significant material contributions from carbonate wall-rocks due to water–rock interaction in ore-forming processes. Stage Ⅱ magnetite grains contain higher Mn concentrations than Stage Ⅰ magnetite grains, which possibly implies more contribution from carbonate rocks. In multiple-element diagrams, the Stage Ⅰ magnetite shows systematic similarities to Kiruna-type magnetite rather than those from other types of deposits. Combined with geological features and previous studies on oxygen isotopes, we conclude that hydrothermal fluids have played a key role in the generation of the Pingchuan low-Ti iron deposit. 展开更多
关键词 SW China Pingchuan IRON DEPOSIT Low-Ti IRON DEPOSIT HYDROTHERMAL MAGNETITE
铁过载及铁死亡在心脏疾病中的研究进展
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作者 方学贤 蔡昭贤 +2 位作者 王浩 闵军霞 王福俤 《科学通报》 EI CAS CSCD 北大核心 2019年第28期2974-2987,共14页
铁作为生命必需的营养元素,在机体组织中的代谢平衡对维持正常的生理功能至关重要.人群流行病学研究和动物实验表明,铁过载在心脏疾病的发生发展过程中发挥重要作用,祛铁可有效缓解心脏疾病进展,但机制尚不清楚.近年来,心脏铁稳态代谢... 铁作为生命必需的营养元素,在机体组织中的代谢平衡对维持正常的生理功能至关重要.人群流行病学研究和动物实验表明,铁过载在心脏疾病的发生发展过程中发挥重要作用,祛铁可有效缓解心脏疾病进展,但机制尚不清楚.近年来,心脏铁稳态代谢及其分子调控机制获得系列重大进展;铁依赖的新型细胞死亡方式——铁死亡(ferroptosis)概念的提出,为深入理解铁过载与心脏疾病间的关联带来了重要契机.近期,作者团队在国际上率先揭示靶向铁死亡是防控心脏疾病有效措施.本综述系统总结了国内外铁过载与铁死亡对心脏疾病发病的影响及作用机制的最新研究进展,并对未来研究方向进行展望与讨论,旨在为心脏疾病预防和治疗提供新思路与新策略. 展开更多
关键词 铁过载 铁死亡 心脏疾病
铁调素及其相关调节药物的研究进展
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作者 陈莹莹 王丽红 郝长来 《国际输血及血液学杂志》 CAS 2019年第1期85-89,共5页
铁是机体内最基本元素,参与机体氧运输、细胞呼吸、DNA复制等,铁代谢紊乱与多种疾病相关,包括贫血性疾病(缺铁性贫血、慢性贫血)和铁过载相关疾病(血色素沉着症)等。铁调素是由肝合成的小分子多肽类激素,对机体铁代谢起负向调控作用,对... 铁是机体内最基本元素,参与机体氧运输、细胞呼吸、DNA复制等,铁代谢紊乱与多种疾病相关,包括贫血性疾病(缺铁性贫血、慢性贫血)和铁过载相关疾病(血色素沉着症)等。铁调素是由肝合成的小分子多肽类激素,对机体铁代谢起负向调控作用,对维持机体铁稳态尤为重要。铁调素由Hamp基因编码,其表达由BMP、STAT等多条信号通路调控,白细胞介素(IL)-6、跨膜丝氨酸蛋白酶(TMPRSS)6等信号分子亦在铁调素的调节中发挥重要作用。笔者现就铁调素的分子结构、作用,以及目前针对铁调素、Hamp基因及其相关信号通路的调节药物的研究进展进行综述。 展开更多
关键词 铁代谢障碍 血色素沉着症 白细胞介素6 铁调素 Hamp基因
Association between iron deficiency and prevalence of thyroid autoimmunity in pregnant and non-pregnant women of childbearing age: a cross-sectional study
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作者 Han-Yi Zhang Xiao-Chun Teng +7 位作者 Zhong-Yan Shan Zhao-Jun Wang Chen-Yan Li Xiao-Hui Yu Jin-Yuan Mao Wei-Wei Wang Xiao-Chen Xie Wei-Ping Teng 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第18期2143-2149,共7页
Background: Thyroid autoimmunity (TAI) is prevalent among women of reproductive age and associated with adverse pregnancy outcomes. This study aimed to investigate the association between iron nutritional status and t... Background: Thyroid autoimmunity (TAI) is prevalent among women of reproductive age and associated with adverse pregnancy outcomes. This study aimed to investigate the association between iron nutritional status and the prevalence of TAI in women during the first trimester of pregnancy and in non-pregnant women of childbearing age. Methods: Cross-sectional analysis of 7463 pregnant women during the first trimester of pregnancy and 2185 non-pregnant women of childbearing age nested within the sub-clinical hypothyroid in early pregnancy study, a prospective collection of pregnant and non-pregnant women’s data, was conducted in Liaoning province of China between 2012 and 2015. Serum thyrotropin, free thyroxine, thyroid peroxidase antibodies (TPOAbs), thyroglobulin antibodies (TgAbs), serum ferritin, and urinary iodine were measured. Iron deficiency (ID) was defined as serum ferritin <15 μg/L and iron overload (IO) was defined as ferritin >150 μg/L. TPOAb-positive was defined as >34 U/mL and TgAb-positive was defined as >115 U/mL. Multilevel logistic regression was conducted to examine the association between TAI and different iron nutritional status after adjusting for potential confounders. Results: The prevalence of isolated TPOAb-positive was markedly higher in women with ID than those without ID, in both pregnant and non-pregnant women (6.28% vs. 3.23%,χ^2 = 10.264, P = 0.002;6.25% vs. 3.70%,χ^2 = 3,791, P = 0.044;respectively). After adjusting for confounders and the cluster effect of hospitals, ID remained associated with TPOAb-positive in pregnant and non-pregnant women (odds ratio [OR]: 2.111, 95% confidence interval [CI]: 1.241–3.591, P = 0.006;and OR: 1.822, 95% CI: 1.011–3.282, P = 0.046, respectively). Conclusion: ID was associated with a higher prevalence of isolated TPOAbs-positive, but not with isolated TgAb-positive, in both pregnant women during the first trimester of pregnancy and non-pregnant women of childbearing age, while IO was not associated with either isolated TPOAb-positive or is 展开更多
关键词 IRON deficiency IRON overload Thyroid AUTOIMMUNITY CROSS-SECTIONAL study PREGNANT CHILDBEARING age
Fe^3+及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响
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作者 李彧钰 朱葛菁 +4 位作者 徐芳依 杨媛媛 徐一 毛丽萍 郑美琴 《中华眼视光学与视觉科学杂志》 CAS CSCD 2019年第2期86-91,共6页
目的:探讨Fe^3+及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响。方法:实验研究。收集2011年6月至2017年2月温州医科大学附属眼视光医院外伤性蜡样芽胞杆菌性眼内炎患者26例并分离出蜡样芽胞杆菌26株。根据患者治疗后有无光感将菌株... 目的:探讨Fe^3+及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响。方法:实验研究。收集2011年6月至2017年2月温州医科大学附属眼视光医院外伤性蜡样芽胞杆菌性眼内炎患者26例并分离出蜡样芽胞杆菌26株。根据患者治疗后有无光感将菌株分为有光感(LP)组和无光感(NLP)组,以蜡样芽胞杆菌模式菌株ATCC14579作为对照组,检测不同菌株在缺铁环境、不同Fe^3+浓度环境、富含Hb环境中生长的光密度(OD)值。采用独立样本t检验对数据进行统计分析。结果:26株眼部来源的蜡样芽胞杆菌在缺铁环境中生长的OD值小于模式菌株ATCC14579(t=54.098,P<0.001)。在一定范围内(0~500μmol/L)增加Fe3+浓度,菌株生长的OD值随之逐渐增加,当Fe^3+浓度高于1000μmol/L时,细菌生长的OD值开始下降。在Fe^3+或血红蛋白铁为主要铁资源的环境中,NLP组菌株生长的OD值均高于LP组(t=2.618,P=0.015;t=2.202,P=0.037)。结论:眼源性蜡样芽胞杆菌的生长对Fe^3+具有较强的依赖性;在Fe^3+或血红蛋白铁为主的铁资源环境中生长较快的菌株感染患者,其临床预后较差。 展开更多
关键词 蜡样芽胞杆菌 血红蛋白铁 眼内炎
Selection of raw materials and control of trace elements for production of high-quality SG iron
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作者 Jia-xin Bai 《中国铸造:英文版》 SCIE 2019年第2期79-87,共9页
During the production of SG iron, the selection of raw materials and control of chemical composition are most important. From the very early days of SG iron production, the effects of trace elements on graphite form a... During the production of SG iron, the selection of raw materials and control of chemical composition are most important. From the very early days of SG iron production, the effects of trace elements on graphite form and matrix structure have been studied, and the allowable concentration limits for their detrimental influence has been decreased year by year, during the last fifty years. This paper has reviewed some of the suggested SG iron trace elements in the literature and in several Chinese foundries. It was found that for most SG iron castings, rare earth elements are still required to neutralize the harmful effects of trace elements and improve SG iron quality. It also found that the use of high purity and ultra-high purity base iron melts enabled integrated, safety-critical and complicated SG iron castings of varying thickness, and heavy-section, to be produced successfully. These SG iron castings have surprisingly good structures, and their mechanical and dynamic properties are vastly superior to those specified in current international SG iron standards. Further study is required on the effects of using high purity and ultra-high purity base melts on the structure and properties of SG iron. 展开更多
关键词 trace elements anti-nodulizing and PEARLITE factors chunky graphite HIGH and ultra-high purity pig IRON HIGH quality SG IRON
Comprehensive evaluation of sintering basic characteristics of iron ore based on grey relational analysis
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作者 Dong-hui Liu Jun-hua Li +3 位作者 Yue Peng Jian-liang Zhang Guang-wei Wang Xun Xue 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第7期691-696,共6页
Sintering basic characteristics of fourteen iron ores were comprehensively evaluated using micro-sinter and grey relational analysis methods. The results show that magnetite has a low assimilability, high bonding phas... Sintering basic characteristics of fourteen iron ores were comprehensively evaluated using micro-sinter and grey relational analysis methods. The results show that magnetite has a low assimilability, high bonding phase strength, and high crystal strength. Hematite presents a good assimilability, while limonite exhibits a strong assimilability, but the bonding phase strength and crystal strength of these two kinds of iron ores are comparatively low. Great difference in liquid flowability exists for the same kind of iron ores. When the assimilation temperature of the sinter mixture is too high, limonite can be added;when the bonding phase strength or crystal strength of the sinter mixture is too low, magnetite can be added. The liquid fluidity of the sinter mixture can be adjusted according to the ratios of corresponding iron ores. Grey relational analysis is an effective method to evaluate the comprehensive sintering characteristics of iron ores, which can provide theoretical basis for the purchasing department of the steel enterprises. 展开更多
关键词 IRON ORE Basic characteristics SINTER GREY RELATIONAL analysis IRON ORE PURCHASING ORE proportioning optimization
Effects of Phosphorus and Iron on Microstructures and Mechanical Properties in NiCrFe-Based Alloys
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作者 Xin-Tong Lian Wen-Ru Sun +2 位作者 Fang Liu Dan-Dan Zheng Xin Xin 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第5期659-667,共9页
The microstructures and mechanical properties, especially creep properties, of the NiCrFe-based alloys with various contents of phosphorus and iron were investigated. The results showed that the tensile yield strength... The microstructures and mechanical properties, especially creep properties, of the NiCrFe-based alloys with various contents of phosphorus and iron were investigated. The results showed that the tensile yield strength decreased with increasing iron contents while had no obvious change with the addition of phosphorus. For creep properties, the alloy with15.8 wt% iron and 0.09 wt% phosphorus possessed the longest creep life(679 h) among all alloys. Only M23C6 was formed in the alloys with low phosphorus contents, while both intergranular M3P and M23C6 precipitated with the increment of phosphorus, which enhanced the strength of grain boundary by hindering the movements of dislocations during creep tests. The reasons for the enhancement of creep life were mainly related to the solid solution strengthening effect of phosphorus and optimization of grain boundary precipitations by phosphorus. 展开更多
关键词 NiCrFe-based alloys PHOSPHORUS IRON MICROSTRUCTURES CREEP properties
辐射剂量和机型对瞬时kVp切换单源双能CT物质分离技术肝脏铁与脂肪定量评估的影响 预览
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作者 谢婷婷 曾建奇 +4 位作者 石桥 黄嵘 冯飞 成官迅 郭金 《放射学实践》 北大核心 2019年第6期597-602,共6页
目的:探讨辐射剂量、机型对瞬时kVp切换单源双能CT肝脏铁和脂肪沉积定量评估的影响。方法:制作肝脏铁沉积体模(铁浓度分别为50.000、25.000、12.500、6.250、3.125、0mg/mL大鼠肝脏匀浆液)、脂肪沉积体模(脂肪体积百分比分别为100%、60%... 目的:探讨辐射剂量、机型对瞬时kVp切换单源双能CT肝脏铁和脂肪沉积定量评估的影响。方法:制作肝脏铁沉积体模(铁浓度分别为50.000、25.000、12.500、6.250、3.125、0mg/mL大鼠肝脏匀浆液)、脂肪沉积体模(脂肪体积百分比分别为100%、60%、30%、10%、0%大鼠肝脏匀浆液):①应用256-MDCT分别以管电流200、320、485mA扫描体模,管电压80、140kVp瞬时切换,相应CTDIvol分别为4.88,8.21,12.64mGy;②应用64-MDCT扫描体模,管电流为375mA、CTDIvol为12.92mGy。以标准算法分别重建铁(水)、脂肪(水)基物质图像,将图像传至ADW4.6工作站,利用GSI分析软件(GSIViewer)分析,于体模内每个试管横断面中心放置3个直径为6mm、面积为28.26mm2圆形感兴趣区(ROI),然后记录其平均值为各ROI虚拟铁浓度值(VIC)、虚拟脂肪浓度值(VFC),先对256-MDCT3组辐射剂量下的VIC、VFC分别进行单因素方差(ANOVA)分析;再分析256-MDCT辐射剂量为12.64mGy下、64-MDCT辐射剂量为12.92mGy下,VIC与肝脏铁浓度(LIC)相关性,VFC与肝实际脂肪浓度(LFC)的相关性。结果:①ANOVA分析显示3组CTDIvol下肝铁沉积模型VIC组间差异P=0.993(F=0.007),组间差异无统计学意义;三组CTDIvol下肝脂肪沉积模型VFC组间差异P=0.976(F=0.024),组间差异无统计学意义;即不同辐射剂量下测得的3组VIC、VFC组间差异均无统计学差异。②256-MDCT组CTDIvol为12.64mGy下与64-MDCT组CTDIvol为12.92mGy下,两组铁沉积模型VIC与LIC均呈高度正相关,相关系数r=0.998(P=0.000),256-MDCT组12.64mGy下拟合铁的线性方程为y=2.179x-2.923(y为LIC,x为VIC,R^2=0.996),64-MDCT组12.92mGy下拟合铁的线性方程为y=2.714x+16.971(R^2=0.996);两组脂肪沉积模型VFC与LFC均呈高度正相关,相关系数r=1.000(P=0.000);256-MDCT组12.64mGy下Fat线性方程:y=0.064x+23.44(y为LFC,x为VFC,R^2=0.868);64-MDCT组375mA下Fat线性方程:y=0.09x-60.442(R^2=0.994)。结论:辐射剂量对双能量CT物质分离技术定量评估肝脏铁、� 展开更多
关键词 双能量CT 辐射剂量 脂肪
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电渣精炼去除工业纯铝中杂质Fe的研究
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作者 陈冲 李红菊 《特种铸造及有色合金》 CAS 北大核心 2019年第4期446-449,共4页
研究了添加Na2B4O7的KCl-NaCl-Na3AlF6混合渣剂电渣精炼去除工业纯铝中杂质Fe的效果。研究发现,工业纯铝中的Fe含量随着电渣重熔速率的降低而不断减少,当重熔速率为180g·min-1时,电渣精炼除Fe效果最好,Fe含量从电渣精炼前的0.42%... 研究了添加Na2B4O7的KCl-NaCl-Na3AlF6混合渣剂电渣精炼去除工业纯铝中杂质Fe的效果。研究发现,工业纯铝中的Fe含量随着电渣重熔速率的降低而不断减少,当重熔速率为180g·min-1时,电渣精炼除Fe效果最好,Fe含量从电渣精炼前的0.42%减少到0.20%,杂质Fe的去除率超过50%。Fe含量的降低是因为熔融渣剂捕获了Al熔体与熔融渣剂反应生成的富Fe中间化合物Fe2B。电渣精炼除Fe反应的热力学计算表明渣剂中的Na2B4O7能与Al熔体中的杂质Fe自发反应生成中间化合物Fe2B。电渣精炼除Fe后工业纯铝的抗拉强度和伸长率随着Fe含量的降低得到明显改善。 展开更多
关键词 电渣精炼 AL FE 净化
高炉瓦斯泥的综合利用 预览
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作者 郑虹雨 孙艳 +1 位作者 张树立 王权福 《中国资源综合利用》 2019年第7期79-82,共4页
高炉瓦斯泥中含量很高的组分有碳、铁和一些有色金属,瓦斯泥是一种非常有价值的可再生资源,如果不能对其有效地加以利用,不仅会造成资源的不合理配置,还会使大气环境恶化。本文对瓦斯泥的特点、组成及回收方法进行了概述,剖析了瓦斯泥... 高炉瓦斯泥中含量很高的组分有碳、铁和一些有色金属,瓦斯泥是一种非常有价值的可再生资源,如果不能对其有效地加以利用,不仅会造成资源的不合理配置,还会使大气环境恶化。本文对瓦斯泥的特点、组成及回收方法进行了概述,剖析了瓦斯泥的基本特性,综述了瓦斯泥中有利用价值成分综合利用的常见方法,如矿选、化学浸出和直接还原,以促进资源的循环利用,最大限度地利用资源。 展开更多
关键词 高炉瓦斯泥 综合利用 有色金属
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阿尔茨海默病患者血清微量元素同型半胱氨酸水平与认知功能的相关性研究
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作者 陈黎明 胡龙 《中国基层医药》 CAS 2019年第18期2209-2214,共6页
观察老年阿尔茨海默病患者血清微量元素、同型半胱氨酸(Hcy)水平与认知功能相关性.方法选择2017年1月至2018年12月在温州市第七人民医院内科诊疗的阿尔茨海默病患者65例作为研究组,并选择同期在该院体检中心体检结果健康人50例作为对照... 观察老年阿尔茨海默病患者血清微量元素、同型半胱氨酸(Hcy)水平与认知功能相关性.方法选择2017年1月至2018年12月在温州市第七人民医院内科诊疗的阿尔茨海默病患者65例作为研究组,并选择同期在该院体检中心体检结果健康人50例作为对照组.使用MMSE量表(简易智力状态检查,Mini-mental State Examination,MMSE)对患者的认知情况进行测评,得分为27~30 分属于认知功能正常,得分<27分为认知功能障碍,得分为21~26分为轻度认知功能障碍,得分10~20分为中度认知功能障碍,得分0~9分为重度认知功能障碍.检测分析所有研究对象的同型半胱氨酸、同型半胱氨酸以及血清铜、铁、锌水平.铜的正常值为7.12~33.8 μmol/L,锌的正常值为67.72~111.30 μmol/L,铁的正常值为7.27~9.85 μmol/L.结果对照组血清铜水平明显低于中度、重度患者;轻度患者的血清铜水平明显低于中度、重度患者;差异有统计学意义(F=12.796,P=0.003).对照组血清铁水平明显高于轻度、中度和重度患者,差异有统计学意义(F=3.332,P=0.021).对照组的血清锌水平明显高于轻、中、重度患者,差异有统计学意义(F=123.618,P=0.000).轻度患者与中度、重度患者之间血清锌浓度差异有统计学意义( F=26.367,P=0.000),而中度患者的血清锌浓度明显低于重度患者(F=12.375,P=0.009).研究组轻度、中度以及重度的患者同型半胱氨酸与水平均显著高于对照组,差异有统计学意义(F=6.549,P=0.020).患者血清铜浓度与患者的MMSE量表评分互为正相关关系(r=10.100,P=0.000),患者血清铜浓度越高患者的MMSE量表得分越高,即患者的认知功能障碍程度越严重;患者血清锌、铁浓度与患者的MMSE量表评分互为负相关关系(r=6.039,P=0.037),患者血清锌浓度越低时患者的MMSE量表得分越高,即患者的认知功能障碍程度越轻.结论阿尔茨海默病患者血清铁、锌、铜浓度的改变与认知功能有较为密切的 展开更多
关键词 阿尔茨海默病 同型半胱氨酸 认知
赞比亚某硫化镍精矿氧压酸浸研究 预览
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作者 谢铿 刘三平 王海北 《有色金属:冶炼部分》 CAS 北大核心 2019年第10期6-10,共5页
以赞比亚某铜镍矿浮选得到的硫化镍精矿为研究对象,采用加压湿法冶金工艺处理,研究镍、铜、铁的浸出行为,考察了浸出温度、硫酸用量、氧分压、液固比、反应时间等因素的影响。在200℃、硫酸用量每吨精矿100 kg、氧分压0.5 MPa、液固比4... 以赞比亚某铜镍矿浮选得到的硫化镍精矿为研究对象,采用加压湿法冶金工艺处理,研究镍、铜、铁的浸出行为,考察了浸出温度、硫酸用量、氧分压、液固比、反应时间等因素的影响。在200℃、硫酸用量每吨精矿100 kg、氧分压0.5 MPa、液固比4∶1、反应时间3 h的优化条件下进行浸出,镍和铜的浸出率均大于99.5%。高温和高氧分压条件利于镍的浸出,镍浸出速度更快。维持上述条件不变,将氧分压增大到0.8 MPa时,仅需浸出1.5 h,镍的浸出率就可达到99%左右。 展开更多
关键词 硫化镍精矿 氧压酸浸
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全国地下水质分布及变化特征 预览
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作者 李圣品 李文鹏 +1 位作者 殷秀兰 金爱芳 《水文地质工程地质》 CAS CSCD 北大核心 2019年第6期1-8,共8页
以2013—2017年地下水监测站点水质监测数据为基础,统计地下水质监测指标的变化特征,筛查影响地下水质的主要指标,研究地下水质变化规律。选取2013—2017年具备连续监测数据的地下水监测井,对常规20项监测指标进行分析。研究发现:就监... 以2013—2017年地下水监测站点水质监测数据为基础,统计地下水质监测指标的变化特征,筛查影响地下水质的主要指标,研究地下水质变化规律。选取2013—2017年具备连续监测数据的地下水监测井,对常规20项监测指标进行分析。研究发现:就监测站点水质指标而言,总硬度、铁、锰、“三氮”等超标率均达到了10%及以上,是导致地下水水质恶化的主要指标。总硬度超标集中在华北、东北、西南和西北地区的监测井,超标率在各省市间差别较大。氨氮超标率在各省市地区的监测井中差别较大,超标较为严重的省份是黑龙江、江苏、广东和宁夏。硝酸盐氮超标率年际变化稳定,华北、东北和西北地区的监测井中硝酸盐氮超标较为严重。亚硝酸盐氮超标在华北、东北和西北,以及上海、江苏、湖北、广西和贵州的监测井中较为严重。铁、锰超标主要集中在华北、华东、中南地区的监测井中,东三省、安徽、湖北、四川、宁夏等省份尤其严重。基于地下水监测井统计数据,在全国尺度上对地下水质量进行了综合分析评价,总结出了地下水监测中需要着重关注的指标,如“三氮”总硬度,铁、锰等。 展开更多
关键词 总硬度 氨氮 硝酸盐氮 亚硝酸盐氮 地下水水质 监测
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电感耦合等离子体原子发射光谱法测定辛酸铑催化剂中铂钯铅铁铜铝镍 预览
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作者 王应进 李秋莹 +3 位作者 李玉萍 徐光 马媛 杨晓滔 《冶金分析》 CAS 北大核心 2019年第6期24-28,共5页
准确测定辛酸铑催化剂中杂质元素含量,是判定产品是否合格的重要指标之一。以往常采用直流电弧发射光谱法(摄谱法)进行检测,但测定周期长,且重复性较差。用电感耦合等离子体原子发射光谱法(ICP-AES)测定辛酸铑催化剂中微量杂质元素时,... 准确测定辛酸铑催化剂中杂质元素含量,是判定产品是否合格的重要指标之一。以往常采用直流电弧发射光谱法(摄谱法)进行检测,但测定周期长,且重复性较差。用电感耦合等离子体原子发射光谱法(ICP-AES)测定辛酸铑催化剂中微量杂质元素时,辛酸铑催化剂样品中含有的大量有机组分和铑基体会对测定有严重干扰。实验采用反复滴加硝酸消解样品中有机组分,再用王水溶解盐类,选用合适背景点扣除的方式消除铑基体的干扰,建立了使用ICP-AES测定辛酸铑催化剂中0.001%~0.1%(质量分数)Pt、Pd、Pb、Fe、Cu、Al、Ni等7种微量杂质元素的方法。各元素在0.10~10.00μg/mL范围内与其发射强度呈线性关系,相关系数均大于0.999 9;方法检出限(μg/mL)为0.075(Pt)、0.003 3(Pd)、0.015(Pb)、0.003 6(Fe)、0.010(Cu)、0.001(Al)、0.012(Ni)。实验方法用于测定辛酸铑催化剂样品中Pt、Pd、Pb、Fe、Cu、Al、Ni,结果的相对标准偏差为(RSD,n=7)为1.4%~9.6%。按照实验方法测定辛酸铑催化剂中Pt、Pd、Pb、Fe、Cu、Al、Ni,并与直流电弧发射光谱法的测定结果进行比对,结果相一致。 展开更多
关键词 电感耦合等离子体原子发射光谱法(ICP-AES) 辛酸铑催化剂
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Optimization of Chelation Process for Complex Microelement Iron Supplement Derived from Pig Blood by Response Surface Methodology 预览
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作者 Jingjing HUANG Yan YAN +3 位作者 Fusheng ZHANG Junfeng YIN Yingqin ZHOU Ningning XIE 《农业生物技术:英文版》 CAS 2019年第1期235-240,共6页
[Objectives]This study aimed to optimize the chelation process for complex microelement iron supplement derived from pig blood by response surface methodology.[Methods]On the basis of single-factor test,pH value,conce... [Objectives]This study aimed to optimize the chelation process for complex microelement iron supplement derived from pig blood by response surface methodology.[Methods]On the basis of single-factor test,pH value,concentration of polypeptide solution and volume ratio of polypeptide solution to FeCl 2 solution were selected as influencing factors with Fe(II)chelation rate as the indicator for Box-Behnken central composite experimental design with three factors and three levels.The effects of three factors on the response value were analyzed by response surface methodology.[Results]The optimized chelation process for complex microelement iron supplement derived from pig blood by response surface methodology was as follows:pH 5.40,polypeptide solution concentration 2.27%,volume ratio of polypeptide solution to FeCl 2 solution 2.16∶1.Under this condition,the predictive Fe(II)chelation rate of iron supplement was 79.37%,while the actual value was 79.41%.[Conclusions]The optimized process may provide new thoughts for the development and utilization of complex microelement iron supplement derived from pig blood. 展开更多
关键词 Response surface METHODOLOGY PIG BLOOD protein Iron SUPPLEMENT Fe(II)chelation rate
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Pyrolyzed Iron Phthalocyanine-Modified Multi-Walled Carbon Nanotubes as Composite Anode in Marine Sediment Microbial Fuel Cells and Its Electrochemical Performance 预览
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作者 ZAI Xuerong DUAN Zhiwei +2 位作者 CHEN Wei YU Jian FU Yubin 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第6期1395-1401,共7页
Improving the performance of anode is a crucial step for increasing output power of marine sediment microbial fuel cells(MSMFCs)to drive marine monitor to work for a long term on the ocean floor.A pyrolyzed iron phtha... Improving the performance of anode is a crucial step for increasing output power of marine sediment microbial fuel cells(MSMFCs)to drive marine monitor to work for a long term on the ocean floor.A pyrolyzed iron phthalocyanine modified multi-walled carbon nanotubes composite(FePc/MWCNTs)has been utilized as a novel nodified anode in the MSMFC.Its structure of the composite modified anode and electrochemical performance have been investigated respectively in the paper.There is a substantial improvement in electron-transfer efficiency from the bacteria biofilm to the modified anode via the pyrolyzed FePc/MWCNTs composite based on their cyclic voltammetry(CV)and Tafel curves.The electron transfer kinetic activity of the FePc/MWCNTs-modified anode is 1.86 times higher than of the unmodified anode.The maximum power density of the modified MSMFC was 572.3±14 m W m^-2,which is 2.6 times larger than the unmodified one(218.3±11 m W m^-2).The anodic structure and cell scale would be greatly minimized to obtain the same output power by the modified MSMFC,so that it will make the MSMFC to be easily deployed on the remote ocean floor.Therefore,it would have a great significance for us to design a novel and renewable long term power source.Finally,a novel molecular synergetic mechanism is proposed to elucidate its excellent electrochemical performance. 展开更多
关键词 marine sediment microbial fuel cells iron phthalocyanine/multi-walled carbon nanotube composite modified anode electrochemical kinetics power density
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Nanoscale zero-valent iron supported on biochar for the highly efficient removal of nitrobenzene
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作者 Gaoling Wei Jinhua Zhang +4 位作者 Jinqiu Luo Huajian Xue Deyin Huang Zhiyang Cheng Xinbai Jiang 《环境科学与工程前沿(英文)》 SCIE EI CAS CSCD 2019年第4期167-177,共11页
The application of nanoscale zero-valent iron (nZVI) in the remediation of contaminated groundwater or wastewater is limited due to its lack of stability, easy aggregation and iron leaching. To address this issue, nZV... The application of nanoscale zero-valent iron (nZVI) in the remediation of contaminated groundwater or wastewater is limited due to its lack of stability, easy aggregation and iron leaching. To address this issue, nZVI was distributed on oak sawdust-derived biochar (BC) to obtain the nZVI/BC composite for the highly efficient reduction of nitrobenzene (NB). nZVI, BC and nZVI/BC were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). For nZVI/BC, nZVI particles were uniformly dispersed on BC. nZVI/BC exhibited higher removal efficiency for NB than the simple summation of bare nZVI and BC. The removal mechanism was investigated through the analyses of UV-Visible spectra, mass balance and XPS. NB was quickly adsorbed on the surface of nZVI/BC, and then gradually reduced to aniline (AN), accompanied by the oxidation of nZVI to magnetite. The effects of several reaction parameters, e.g., NB concentration, reaction pH and nZVI/BC aging time, on the removal of NB were also studied. In addition to high reactivity, the loading of nZVI on biochar significantly alleviated Fe leaching and enhanced the durability of nZVI. 展开更多
关键词 BIOCHAR NANOSCALE zero-valent iron NITROBENZENE Reduction Adsorption SYNERGISTIC effec
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