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Effects of Copper and Manganese on Hemocyte Apoptosis and Antagonism of Iron and Zinc in Oreochromis niloticus 被引量:1
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作者 白丽蓉 赵志英 《Agricultural Science & Technology》 CAS 2016年第3期684-689,共6页
This study aimed to investigate the effects of copper and manganese on hemocyte apoptosis and the antagonism of iron and zinc in Oreochromis niloticus The heavy metal contents in fish blood and feed were determined by... This study aimed to investigate the effects of copper and manganese on hemocyte apoptosis and the antagonism of iron and zinc in Oreochromis niloticus The heavy metal contents in fish blood and feed were determined by atomic absorption spectrophotometry, and the hemocyte apoptosis was determined by flow cytometry. A total of 360 tilapias were selected, and they were divided randomly and evenly into 12 groups. In the challenge groups, the tilapias were fed with con stant-level copper sulfate(0, 200 mg/kg) and manganese sulfate(0, 120 mg/kg); in the antagonism groups, the tilapias were fed with constant-level zinc sulfate(20320 mg/kg) and iron sulfate(150, 350 mg/kg). After 20-week aquaculture, the hemocyte apoptosis rates in the copper and manganese groups were significantly increased; with the increased addition levels of iron and zinc, the hemocyte apopto sis rates in the iron and zinc groups were significantly reduced, but they were stil higher than that in the control group. In conclusion, excessive copper and manganese can cause apoptosis in hemocytes of O. niloticus. However, the toxic effects of copper and manganese can be antagonized by iron and zinc. 展开更多
关键词 Oreochromis niloticus APOPTOSIS copper manganese iron zinc
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Annual changes of iron, manganese, zinc and copper concentrations in both types of citrus fruit 被引量:2
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作者 XIAO Jia-Xin PENG Shu-An 《广西植物》 CAS CSCD 北大核心 2008年第2期237-241,共5页
关键词 柑橘 果实 含量测定 年周期变化 结实类型
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Iron, Zinc, and Copper Malnutrition among Primary School Children in Lagos, Niagara
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作者 Ifeoma A. Akeredolu Babatunde E. Oguntona +1 位作者 Chinwe Okafor Olufemi J. Osisanya 《Food and Nutrition Sciences》 2011年第10期1063-1070,共8页
This study assessed the iron, zinc and copper status of primary school-attending children in Lagos. A sample of 200 primary School-attending children was randomly selected using a stratified 2 – stage sampling techni... This study assessed the iron, zinc and copper status of primary school-attending children in Lagos. A sample of 200 primary School-attending children was randomly selected using a stratified 2 – stage sampling technique. Data was collected in the 2 major seasons in Nigeria;Dry and Rainy seasons using dietary intake (24 hr dietary recall protocol) venipuncture blood samples, and a self-administered questionnaire. The data were analyzed using descriptive and inferential statistics. Among ages 5 - 8 years, the main dietary intake for iron was 10.66 ± 12.44 mg/d (106% of DRI), for zinc, 7.30 ± 7.39 mg/d (92% of DRI) and for copper, 1.55 ± 1.31 mg/d (390% of DRI). For ages 9 - 13 yrs, the mean intake of micronutrients showed that iron was 11.03 ± 12.72 mg/d (138% of DRI), 3inc was 8.44 ± 7.7 mg/d (105% of DRI) and copper was 3.75 ± 15.17 mg/d (536% of DRI). Biochemical results indicated that 19.8% of the subjects had inadequate serum iron, 21% and 32.1% were zinc and copper deficient respectively prevalence of anemia was 38.1% while iron deficiency anemia was 13.06% and iron deficiency was 34.6%. Dietary intakes did not provide right amounts of micronutrients to meet body requirements. There is the need to formulate and implement nutrition education programs to correct micronutrient deficiency among primary school-attending children in Lagos, Nigeria. 展开更多
关键词 MICRONUTRIENT Status iron zinc copper Primary School Children Nigeria
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Concentrations of copper, zinc and manganese in Tree Sparrow (Passer montanus) at Jixi, Heilongjiang Province, China 被引量:1
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作者 Gong Qian-qian Jin Zhi-min Zou Hong-fei 《Journal of Forestry Research》 CAS CSCD 2012年第2期319-322,共4页
Concentrations of copper (Cu), zinc (Zn) and manganese (Mn) were measured in four tissues of Tree Sparrow (Passer montanus) from three sites in Heilongjiang province, China, during four seasons. Among the four... Concentrations of copper (Cu), zinc (Zn) and manganese (Mn) were measured in four tissues of Tree Sparrow (Passer montanus) from three sites in Heilongjiang province, China, during four seasons. Among the four measured tissues (primary feathers, liver, heart, and pectoral muscle), the highest concentrations were found in feathers (Zn) or liver (Cu and Mn), and the lowest concentrations were in muscle, except Cu. For Mn, mean concentrations of the birds from the three study sites were, in decreasing order: Didao mining area (DMA) 〉 urban district of Jixi (UDJ) 〉 Phoenix Mountain national nature reserve (PMR, the reference site), but not for Zn and Cu. There were significant differences between metal concentrations at the three sites, but differences were not significant for Mn (in muscle and feathers) and Cu (in feathers). For most elements, the mean concentrations were greatest in summer. 展开更多
关键词 copper manganese mining tree sparrow zinc Jixi
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Spectrophotometric Simultaneous Determination of Zinc(II), Manganese(II) and Iron(II) in Pharmaceutical Preparations Using OSC-PLS
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作者 Ali NIAZI zadeh YAZDANIPOUR +2 位作者 ohammad GOODARZI amidreza KAMKAR Ali RAFINEJAD 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第10期1347-1350,共4页
This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All... This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All the factors affecting on the sensitivity were optimized and the linear dynamic range for determination of these metals was found. The PLS modeling was used for the multivariate calibration of the spectrophotometric data. The OSC was used for preprocessing of data matrices and the prediction results of model. The experimental calibration matrix was designed by measuring the absorbance over the range 450-570 nm for 21 samples of 0.05-1.05, 0.10-1.10 and 0.05-1.05μg·mL^-1 of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ), respectively. The RMSEP for zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) using OSC-PLS were 0.0164, 0.0132, 0.0146, respectively. The proposed method was successfully applied the determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparations. 展开更多
关键词 zinc(Ⅱ) manganese(Ⅱ) iron(Ⅱ) SPECTROPHOTOMETRIC OSC-PLS PHARMACEUTICAL
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Trace metals and animal health: Interplay of the gut microbiota with iron, manganese, zinc, and copper 被引量:8
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作者 Edward Alain B.Pajarillo Eunsook Lee Dae-Kyung Kang 《Animal Nutrition》 SCIE CSCD 2021年第3期750-761,共12页
Metals such as iron,manganese,copper,and zinc are recognized as essential trace elements.These trace metals play critical roles in development,growth,and metabolism,participating in various metabolic processes by acti... Metals such as iron,manganese,copper,and zinc are recognized as essential trace elements.These trace metals play critical roles in development,growth,and metabolism,participating in various metabolic processes by acting as cofactors of enzymes or providing structural support to proteins.Deficiency or toxicity of these metals can impact human and animal health,giving rise to a number of metabolic and neurological disorders.Proper breakdown,absorption,and elimination of these trace metals is a tightly regulated process that requires crosstalk between the host and these micronutrients.The gut is a complex system that serves as the interface between these components,but other factors that contribute to this delicate interaction are not well understood.The gut is home to trillions of microorganisms and microbial genes(the gut microbiome)that can regulate the metabolism and transport of micronutrients and contribute to the bioavailability of trace metals through their assimilation from food sources or by competing with the host.Furthermore,deficiency or toxicity of these metals can modulate the gut microenvironment,including microbiota,nutrient availability,stress,and immunity.Thus,understanding the role of the gut microbiota in the metabolism of manganese,iron,copper,and zinc,as well as in heavy metal deficiencies and toxicities,and vice versa,may provide insight into developing improved or alternative therapeutic strategies to address emerging health concerns.This review describes the current understanding of how the gut microbiome and trace metals interact and affect host health,particularly in pigs. 展开更多
关键词 Gut microbiota Microbiome iron manganese zinc copper
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STRENGTHENING CAST IRON MATRIX BY ALLOYINGELEMENTS WITH POSITIVE AND NEGATIVESEGREGATION
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作者 Fan, Z.K. Wang, Y.Q. +1 位作者 Liang, S.H. Huang, H.S. 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第4期329-332,共4页
The combinational use of alloying elements with positive and negative segregation has been shown to be very effective in strengthening the matrix of cast iron. Negative segregation alloying elements, Cu and Si, make t... The combinational use of alloying elements with positive and negative segregation has been shown to be very effective in strengthening the matrix of cast iron. Negative segregation alloying elements, Cu and Si, make the inner parts of dendritic austenites and eutectic cells get good hardenability. On the contrary, positive segregation alloying elements Cr and Mn make the outer parts of dendrites have higher microhardness. Appropriate combination of the above two types of alloying elements can produce a uniform microhardness and high strength in gray cast irons. 展开更多
关键词 Cast iron CHROMIUM copper HARDNESS manganese Segregation (metallography) Silicon Strengthening (metal)
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A barrier to metal movement: Synchrotron study of iron plaque on roots of wetland plants
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作者 Iris Koch Michelle M.Nearing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第6期1-3,共3页
A wetland with attractive plants hosting birds and other wildlife is an esthetically pleasing prospect that is gaining popularity as a way of stabilizing or remediating metalcontaminated soils and sediment(Weber and ... A wetland with attractive plants hosting birds and other wildlife is an esthetically pleasing prospect that is gaining popularity as a way of stabilizing or remediating metalcontaminated soils and sediment(Weber and Gagnon,2014; 展开更多
关键词 Wetland plants Metal contamination Urban brownfield sites X-ray microtomography and microfluorescence copper iron Lead zinc
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Seminal concentrations of trace elements in various animalsand their correlations 被引量:5
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作者 P.Massányi J.Trandzik +3 位作者 P.Nad R.Toman M.Skalická B.Koréneková 《Asian Journal of Andrology》 SCIE CAS CSCD 2003年第2期101-104,共4页
Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and ... Aim: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. Results: The seminal copper concentration was significantly higher in ram [(2.49±0.18) mg/kg] and fox [(2.16±0.53) mg/kg] than that in bull [(1.64±0.21) mg/kg], boar [(1.64±0.28) mg/kg] and stallion (0.86 mg/kg). In boar a significantly higher seminal zinc concentration (171.74±65.72) mg/kg] was found in comparison with stallion [(86.20±45.88) mg/kg], bull [(83.15±61.61) mg/kg], ram [( 60.46±35.37) mg/kg] and fox (13.09±5.22) mg/kg]. The iron concentration in semen was significantly higher in ram [(40.32±10.81) mg/kg), bull [(38.04±22.07) mg/kg] and fox [(33.16±24.36) mg/kg] than that in boar [(16.14±10.35) mg/kg] and stallion (12.68 mg/kg). The seminal cadmium concentration was relatively low [(0.05-0.12) mg/kg] in all studied species. The seminal lead concentration was the highest in ram [(0.35±0.68) mg/kg], which was much higher than in fox [(0.08±0.06) mg/kg], bull [(0.06±0.04) mg/kg], stallion [(0.05±0.05) mg/kg] and boar [0.02±0.03) mg/kg]. The level of seminal nickel was significantly higher in fox [(0.35±0.24) mg/kg] and ram [(0.31±0.19) mg/ kg] in comparison with bull [(0.12±0.07) mg/kg] and boar [(0.06±0.08) mg/kg]. The concentration of nickel in the semen of stallion was (0.20±0.24) mg/kg. There was a high positive correlation between seminal iron and zinc in bull (r=0.723) and stallion (r=0.723), between cadmium and lead in ram (r=0.976) and boar (r=0.973) and between iron and cadmium (r=0.783) and iron and lead (r=0.791) in boar. A high negative correlation between seminal nickel and copper in ram (r=-0.709) and between seminal copper and lead in fox (r=-0.854) was found. Conclusion: There are significant differences in the concentrations of seminal elements in different animals. There is a high concentration of seminal copper in ram and fox, a high zinc level in boar, a high iron level in bull, ram and fox and a high nickel level in ram and fox. 展开更多
关键词 SEMEN copper zinc iron CADMIUM lead nickel
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火焰原子吸收光谱法测定配合饲料中铜、铁和锰含量的不确定度评定
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作者 朱叶萌 黎雄才 王刚 《饲料工业》 CAS 北大核心 2024年第9期115-120,共6页
研究旨在建立火焰原子吸收光谱法测定配合饲料中铜、铁和锰含量的不确定度评定方法,真实反映测量的置信度和准确性。首先分析测定过程中的不确定度来源,对不确定度分量进行量化,然后通过数学模型计算出饲料中铜、铁和锰含量,合成扩展不... 研究旨在建立火焰原子吸收光谱法测定配合饲料中铜、铁和锰含量的不确定度评定方法,真实反映测量的置信度和准确性。首先分析测定过程中的不确定度来源,对不确定度分量进行量化,然后通过数学模型计算出饲料中铜、铁和锰含量,合成扩展不确定度。结果显示:饲料中铜、铁和锰的含量分别为(11±2)、(214±10)、(92±4)mg/kg,不确定度为扩展不确定度,包含因子为2,对应的置信水平是95%。本研究发现样品消解、样品溶液浓度测定和含量重复性测量是影响饲料中铜、铁、锰含量测量中不确定度的主要因素,应特别关注样品的前处理过程、标准工作液的配制,并使待测样品的浓度落在曲线的中间位置,以提高检测准确性。 展开更多
关键词 不确定度 原子吸收光谱法
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Efficacy of Essential Trace Elements Supplementation on Mineral Composition,Sperm Characteristics,Antioxidant Status,and Genotoxicity in Testis of Tebuconazole-treated Rats
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作者 Hajer BEN SAAD Fatma BEN ABDALLAH +4 位作者 Intidhar BKHAIRIA Ons BOUDAWARA Moncef NASRI Ahmed HAKIM Ibtissem BEN AMARA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第10期760-770,共11页
Objective This research was performed to evaluate the effect of tebuconazole(TBZ)on reproductive organs of male rats and to assess the protective role of combined essential trace elements in alleviating the detrimenta... Objective This research was performed to evaluate the effect of tebuconazole(TBZ)on reproductive organs of male rats and to assess the protective role of combined essential trace elements in alleviating the detrimental effect of TBZ on male reproductive function.Methods For this purpose,48 rats were exposed to 100 mg/kg TBZ,TBZ supplemented with zinc(Zn),selenium(Se),copper(Cu),and iron(Fe),TBZ+(Se+Zn);TBZ+Cu;or TBZ+Fe.The experiment was conducted for 30 consecutive days.Results TBZ caused a significant perturbation in mineral levels and reduction in reproductive organs weights,plasma testosterone level,and testicular antioxidant enzyme activities.The TBZ-treated group also showed a significant increase in sperm abnormalities(count,motility,and viability percent),plasma follicle-stimulating hormone and luteinizing hormone concentrations,lipid peroxidation,protein oxidation,and severe DNA degradation in comparison with the controls.Histopathologically,TBZ caused testis impairments.Conversely,treatment with trace elements,in combination or alone,improved the reproductive organ weights,sperm characteristics,TBZ-induced toxicity,and histopathological modifications in testis.Conclusion TBZ exerts significant harmful effects on male reproductive system.The concurrent administration of trace elements reduces testis dysfunction,fertility,and toxicity induced by TBZ. 展开更多
关键词 zinc SELENIUM iron copper Testicular toxicity
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Level of Macronutrients and Microelements of Blood Plasma in Different Forms of Pulmonary Tuberculosis
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作者 Larisa Obukhova Elena Erlykina +4 位作者 Amir Aliyev Rafig Chobanov Vladimir Pimenov Ilya Evdokimov Aliyar Sarvarov 《Journal of Biosciences and Medicines》 2017年第12期81-87,共7页
By the method of atomic emission spectrometry with inductively coupled plasma, the content of macro and microelements in the blood plasma of 35 practically healthy people living in the Northern region of Azerbaijan an... By the method of atomic emission spectrometry with inductively coupled plasma, the content of macro and microelements in the blood plasma of 35 practically healthy people living in the Northern region of Azerbaijan and in the Nizhny Novgorod region of the Russian Federation was studied as well as of 23 patients with pulmonary tuberculosis with different phases of the disease. The elemental homeostasis of the blood plasma did not significantly differ depending on the region of residence, except for the potassium level (by 1.3 times greater for Russians) and strontium (by 10 times higher among the inhabitants of the Northern region of Azerbaijan). In patients with focal pulmonary tuberculosis, there were no significant differences in the content of elements in the blood plasma. With pulmonary tuberculosis, accompanied by decomposition processes, the content of calcium, copper, zinc and iron in blood plasma significantly increases in comparison with healthy people. Analysis of the level of these macro- and microelements can be used to determine the transition of the early form of pulmonary tuberculosis to infiltrative and/or cavernous forms, in which the patient becomes epidemiologically dangerous to others. 展开更多
关键词 Pulmonary Tuberculosis FOCAL FORM CAVERNOUS FORM MACROELEMENTS MICROELEMENTS Calcium copper zinc iron
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Effects of Heavy Metal Ions (Fe<sup>3+</sup>, Cu<sup>2+</sup>, Zn<sup>2+</sup>and Cr<sup>3+</sup>) on the Productivity of Biogas and Biomethane Production
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作者 N. B. Golub A. V. Shynkarchuk +1 位作者 O. A. Kozlovets M. V. Kozlovets 《Advances in Bioscience and Biotechnology》 2022年第1期1-14,共14页
It was shown that the concentration of heavy metal ions Fe<sup>3+</sup>, Cu<sup>2+</sup>, Cr<sup>3+</sup> and Zn<sup>2+</sup>, which are contained in the fermentation me... It was shown that the concentration of heavy metal ions Fe<sup>3+</sup>, Cu<sup>2+</sup>, Cr<sup>3+</sup> and Zn<sup>2+</sup>, which are contained in the fermentation medium, affects the process of biogas production. The aim of this paper was to establish the concentration of ions, which makes it possible to increase the yield of biogas and the methane content in it. The total yield of biogas per unit of dry organic matter, methane and the kinetics of changes in the yield of biogas during fermentation of cattle manure in the presence of different concentrations of metal ions in the anaerobic environment. It was established that the content of Fe<sup>3+</sup>, Cu<sup>2+</sup> is up to 80 mg/dm<sup>3</sup>, Cr<sup>3+</sup> and Zn<sup>2+</sup> is up to 50 mg/dm<sup>3</sup> in the medium lead to increased methane production by anaerobic association of microorganisms due to the <span>effect on the activity of enzyme systems in comparison with the sample</span> without the addition of metal ions. It was found that the rational concentrations to increase the methane yield in the biogas obtained by fermentation of cattle manure are: Fe<sup>3+</sup>-20 - 40 mg/dm<sup>3</sup>, Cu<sup>2+</sup>-40 - 60 mg/dm<sup>3</sup>, Cr<sup>3+</sup>-10 mg/dm<sup>3</sup>. The increase in the concentration of metal ions above rational values leads to a decrease in the methane content in biogas. It was shown that zinc ions have a positive effect on methane production, but reduce the total biogas <span>yield and, accordingly, the degree of conversion of organic raw materials. </span>Therefore, the rational concentration of Zn<sup>2+</sup> in the fermentation medium is 10 mg/dm<sup>3</sup>. 展开更多
关键词 Heavy Metal iron zinc copper Сhromium BIOGAS BIOMETHANE
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Gene Expression and Activities of SOD in Cucumber Seedlings Were Related with Concentrations of Mn^(2+),Cu^(2+),or Zn^(2+) Under Low Temperature Stress 被引量:17
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作者 GAO Jun-jie LI Tao YU Xian-chang 《Agricultural Sciences in China》 CAS CSCD 2009年第6期678-684,共7页
Effects of increasing Mn^2+, Cu^2+, or Zn^2+ on SOD expressions were studied in cucumber seedlings under low temperature stress. Both gene expressions and activities of Cu/Zn-SOD and Mn-SOD in cucumber seedling lea... Effects of increasing Mn^2+, Cu^2+, or Zn^2+ on SOD expressions were studied in cucumber seedlings under low temperature stress. Both gene expressions and activities of Cu/Zn-SOD and Mn-SOD in cucumber seedling leaves were induced by increasing Mn^2+, Cu^2+, or Zn^2+ under low temperature stress, especially 48 h afterwards. The activities of Cu/Zn-SOD and Mn-SOD at 0 and 48 h after treatment were in accordance with their gene expression levels, which implied that the transcriptional regulation plays key roles in regulating their activities at the early stage of low temperature stress. Gene expressions of Cu/Zn-SOD and Mn-SOD declined at 96 h, but Cu/Zn-SOD and Mn-SOD activities still remain high, which suggested that Cu/Zn-SOD and Mn-SOD activities might be regulated by other factors after transcription at the later stage of low temperature stress. Therefore, we concluded that the increasing Mn^2+, Cu^2+, or Zn^2+ could increase the capacity of scavenging ROS in cucumber seedlings under low temperature stress by inducing gene expressions of Cu/ Zn-SOD and Mn-SOD, elevating activities of Cu/Zn-SOD, Mn-SOD, or regulating other factors after transcription. 展开更多
关键词 real-time quantitative PCR cucumber seedlings SOD low temperature stress manganese copper zinc
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锂电三元前驱体工艺设计要点控制研究 被引量:2
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作者 陈刚 《化工设计通讯》 CAS 2024年第6期105-108,共4页
锂电池材料分为正极材料、负极材料、隔膜、电解液等,正极材料是锂电池材料的关键性材料之一,三元前驱体是生产三元正极材料的重要上游材料。在三元前驱体工艺设计中,关注重点工艺控制条件、废水处理工艺设计、铜铁锌等异物引入的防护... 锂电池材料分为正极材料、负极材料、隔膜、电解液等,正极材料是锂电池材料的关键性材料之一,三元前驱体是生产三元正极材料的重要上游材料。在三元前驱体工艺设计中,关注重点工艺控制条件、废水处理工艺设计、铜铁锌等异物引入的防护措施、工艺智能化设计,优化设计提升产品的竞争力,推动锂电池行业的发展。 展开更多
关键词 锂电三元前驱体 重点工艺控制条件 废水处理工艺 铜铁锌等异物 智能化
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西昆仑晚古生代盆地演化与成矿作用
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作者 张羽佳 李溪遥 +2 位作者 吴承泉 徐进鸿 张正伟 《矿物学报》 CAS CSCD 北大核心 2024年第4期478-492,共15页
在西昆仑北部地区,由于古特提斯洋汇聚作用,导致形成弧后伸展构造带以及一系列晚古生代沉积盆地。本文着重综述以下几个问题:1)位于塔里木地块南缘上的塔木-卡兰古盆地带,由于坳陷作用连续沉积了中泥盆统-上二叠统地层,其构造位置相当... 在西昆仑北部地区,由于古特提斯洋汇聚作用,导致形成弧后伸展构造带以及一系列晚古生代沉积盆地。本文着重综述以下几个问题:1)位于塔里木地块南缘上的塔木-卡兰古盆地带,由于坳陷作用连续沉积了中泥盆统-上二叠统地层,其构造位置相当于远域大陆弧后环境盆地;位于西昆仑地块北缘的奥依塔格-库尔良弧后盆地带,由于裂陷作用断续地沉积了中泥盆统-上二叠统地层,其构造位置相当于弧后盆地。虽然这两个盆地带之间被铁克里克断隆带所分隔,但它们的演化过程具有同时性。2)盆地中主要有两期岩浆岩活动,一是与盆地扩张期同生的“双峰式”岩浆岩(339~291 Ma),二是与盆地闭合有关的中酸性岩浆岩(265~206 Ma);3)在盆地演化过程中,中泥盆世-早二叠世是盆地扩张期,在局部坳陷的封闭盆地和缺氧环境下形成同生沉积矿床,主要包括海相砂岩型铜矿床、喷流沉积型铅锌矿床、沉积锰矿床以及VMS型铜矿床;中二叠世-早三叠世是盆地闭合期,由于盆-山转换作用导致沉积基底褶皱和岩浆活动,并形成了构造-热液和岩浆热液成矿作用。总之,晚古生代区域伸展构造环境受制于古特提斯汇聚作用,在这些盆地扩张到闭合的演化过程中,形成沉积型矿床、岩浆热液型矿床和构造-热液型矿床。 展开更多
关键词 晚古生代盆地 弧后伸展环境 铅-锌-铜-锰矿床 西昆仑
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乳糜泻与微量元素相关性研究进展
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作者 凯丽比努尔·努尔麦麦提 李婷 高峰 《胃肠病学》 2024年第2期114-118,共5页
乳糜泻是一种由遗传易感个体摄入麸质引起的自身免疫病,主要累及小肠,引起小肠绒毛萎缩。许多乳糜泻患者因肠道炎症出现各种营养素吸收障碍,导致体内营养失衡,包括各种微量元素失衡。虽然微量元素在人体中含量很少,但因其特殊生理功能,... 乳糜泻是一种由遗传易感个体摄入麸质引起的自身免疫病,主要累及小肠,引起小肠绒毛萎缩。许多乳糜泻患者因肠道炎症出现各种营养素吸收障碍,导致体内营养失衡,包括各种微量元素失衡。虽然微量元素在人体中含量很少,但因其特殊生理功能,对人体健康具有重要作用。部分乳糜泻相关并发症与不同微量元素失衡有关。此外,研究发现多种微量元素在乳糜泻发生、发展中发挥作用。本文就乳糜泻患者中一些重要微量元素水平,以及近年各种微量元素在乳糜泻发病机制、病情评估和治疗中作用的研究进展作一综述。 展开更多
关键词 乳糜泻 微量元素 膳食 无麸质
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生物活性离子改性透钙磷石骨水泥的生物和理化性能
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作者 曾诚 于欢欢 +3 位作者 龚玉康 王晨浩 张印恩 高文山 《中国组织工程研究》 CAS 北大核心 2024年第22期3561-3568,共8页
背景:透钙磷石骨水泥作为一种骨替代和骨填充材料,因其具有良好的生物相容性、骨传导性等优点,尤其是相比于其他磷酸钙类骨水泥具有更好的生物降解能力,在骨修复方面有重要应用价值,但也因其存在机械性能不足、固化反应快及注射性能差... 背景:透钙磷石骨水泥作为一种骨替代和骨填充材料,因其具有良好的生物相容性、骨传导性等优点,尤其是相比于其他磷酸钙类骨水泥具有更好的生物降解能力,在骨修复方面有重要应用价值,但也因其存在机械性能不足、固化反应快及注射性能差等问题的限制,目前一般只能用于非负重区骨的修复。目的:探讨生物活性离子(金属离子和非金属离子)改性透钙磷石骨水泥,以期拓展使用范围。方法:利用Pub Med、Science Direct和中国知网、万方数据库检索2018-2023年发表的文献,中文检索词为“金属离子,铁,铜,锶,镁,锌,非金属离子,改性,骨,透钙磷石骨水泥”;英文检索词为“metal ion,iron,Fe,copper,Cu,strontium,Sr,magnesium,Mg,zinc,Zn,non-metal ion,modification,bone,Brushite Cements”。通过阅读标题、摘要对所得文献进行初筛,排除重复及内容不相关文献,最终纳入64篇文献进行综述。结果与结论:(1)生物活性离子影响透钙磷石骨水泥水化反应过程,不同离子以离子取代的方式掺入透钙磷石骨水泥晶体结构中,改变了骨水泥晶体形态,引起凝固时间、注射性、抗压强度等理化性能改变。(2)离子改性的透钙磷石骨水泥因不同的晶体结构而产生不同的离子释放效应,不同类型离子具有如促血管生成/成骨、抗菌及抗肿瘤等特性而发挥作用,此外,透钙磷石骨水泥具有良好的生物降解性,这对于各离子性能的发挥具有极大优势。(3)不同离子改性透钙磷石骨水泥理化性能影响如下:铁、铜、锶、镁、锌、银、钴可延长凝固时间;锶、镁可提高注射性能;铜、锶、镁、银、硅可增强抗压强度;能同时改善透钙磷石骨水泥以上3种理化性能的离子有锶、镁;良好的理化性能是临床应用的前提,故离子改善透钙磷石骨水泥的凝固时间、注射性及抗压强度等性能对骨水泥的研究应用具有重要意义。(4)不同离子改性透钙磷石骨水泥生物性能影响如下:铜、锶、镁、锌、钴、锂、硅、硒具有促血管生成/成骨效应;铁、铜、镁、锌、银具有抗菌特性;镁离子具有抗炎特性;铜、硒具有抗肿瘤性。(5)综上所述,镁离子能改善透钙磷石骨水泥凝固时间、注射性和抗压强度,同时具有促新生血管生成/成骨及抗菌性,对合并感染的骨缺损治疗具有良好应用前景;此外,铜还具有抗肿瘤特性,因此铜离子在感染、肿瘤引起的骨缺损治疗方面有巨大潜力;只是目前相关研究仍处于基础研究阶段,不同离子掺杂浓度和合成条件等对透钙磷石骨水泥理化性能的影响需进一步探索,同时对于生物性能影响也需更长期的研究观察。 展开更多
关键词 金属离子 非金属离子 改性 透钙磷石骨水泥
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Mn-SOD and CuZn-SOD polymorphisms and interactions with risk factors in gastric cancer 被引量:12
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作者 Jian-Feng Yi Shi-Liang Kang +6 位作者 Xiang-Ting Zeng Yu-Min Li Tao Liu Jun-Qiang Zhang Wen-Ting He Xun Li Wen-Ce Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第37期4738-4746,共9页
AIM: To investigate the effects of superoxide dismutase (SOD) polymorphisms (rs4998557 , rs4880), Helicobacter pylori (H. pylori ) infection and environmental factors in gastric cancer (GC) and malignant potential of ... AIM: To investigate the effects of superoxide dismutase (SOD) polymorphisms (rs4998557 , rs4880), Helicobacter pylori (H. pylori ) infection and environmental factors in gastric cancer (GC) and malignant potential of gastric precancerous lesions (GPL). METHODS: Copper-zinc superoxide dismutase (SOD1, CuZn-SOD)-G7958A (rs4998557 ) and manganese superoxide dismutase (SOD2, Mn-SOD)-Val16Ala (rs4880 ) polymorphisms were genotyped by SNaPshot multiplex polymerase chain reaction (PCR) in 145 patients with GPL (87 cases of gastric ulcer, 33 cases of gastric polyps and 25 cases of atrophic gastritis), 140 patients with GC and 147 healthy controls. H. pylori infection was detected by immunoblotting analysis. RESULTS: The SOD1-7958A allele was associated with a higher risk of gastric cancer [odds ratio (OR) = 3.01, 95% confidence intervals (95% CI): 1.83-4.95]. SOD216Ala/Val genotype was a risk factor for malignant potential of GPL (OR = 2.04, 95% CI: 1.19-3.49). SOD216Ala/genotype increased the risk of gastric cancer (OR = 2.85, 95% CI: 1.66-4.89). SOD1-7958A/genotype, SOD2-16Ala/genotype, alcohol drinking, positive family history and type Ⅰ H. pylori infection were associated with risk of gastric cancer, and there were additive interactions between the two genotypes and the other three risk factors. SOD2-16Ala/Val genotype and positive family history were associated with malignant potential of GPL and jointly contributed to a higher risk for malignant potential of GPL (OR = 7.71, 95% CI: 2.10-28.22). SOD1-7958A/genotype and SOD2-16Ala/genotype jointly contributed to a higher risk for gastric cancer (OR = 6.43, 95% CI: 3.20-12.91). CONCLUSION: SOD1-7958A/and SOD2-16Ala/-genotypes increase the risk of gastric cancer in Chinese Han population. SOD2-16Ala/-genotype is associated with malignant potential of GPL. 展开更多
关键词 copper-zinc superoxide dismutase manganese superoxide dismutase Gastric cancer Gastric precancerous lesions Gene polymorphisms Interaction
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满洲里-克鲁伦成矿带铁锰铅锌等多金属矿成矿规律 被引量:1
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作者 丁小燕 王婷婷 +1 位作者 张六虎 潘勤梅 《中国锰业》 2024年第4期53-60,共8页
满洲里-克鲁伦成矿带于东北亚地区,是重要的多金属矿产资源集中区。通过对成矿带的地理位置和矿产资源的分布状况进行介绍,详细分析了成矿时代的3个主要阶段:新太古代-古元古代、晚古生代和中生代。其中中生代的成矿作用最为强烈。同时... 满洲里-克鲁伦成矿带于东北亚地区,是重要的多金属矿产资源集中区。通过对成矿带的地理位置和矿产资源的分布状况进行介绍,详细分析了成矿时代的3个主要阶段:新太古代-古元古代、晚古生代和中生代。其中中生代的成矿作用最为强烈。同时,通过探讨成矿带的地质构造特征,包括含矿建造特征、区域构造控矿作用、中生代火山构造以及岩浆侵入活动的控矿作用,总结了区域成矿模式,指出成矿带的金属成矿主要集中于中生代,并且成矿作用表现出多期次、多阶段性的特点。研究结果为理解该地区的成矿作用提供了新的视角,并对未来的地质找矿资源勘查工作提供了科学依据。 展开更多
关键词 兴蒙造山带 铁锰铅锌 多金属矿 矿化成矿期 成矿规律
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