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畜禽肠道菌群耐药基因的研究进展 被引量:1
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作者 赵树生 和世春 +5 位作者 戴思凡 王梓蓓 吴东旺 余催 李清 毛华明 《饲料工业》 北大核心 2025年第4期154-160,共7页
当前,抗生素耐药性的出现和传播威胁着人类和动物的健康。动物微生物群中的耐药性细菌是抗生素抗性基因的重要贮存库,且这些病原菌可以通过水平基因转移或质粒交换将抗生素抗性基因转移到肠道菌群中,从而使肠道菌群携带抗生素抗性基因,... 当前,抗生素耐药性的出现和传播威胁着人类和动物的健康。动物微生物群中的耐药性细菌是抗生素抗性基因的重要贮存库,且这些病原菌可以通过水平基因转移或质粒交换将抗生素抗性基因转移到肠道菌群中,从而使肠道菌群携带抗生素抗性基因,严重威胁畜禽健康养殖。文章主要对影响肠道菌群抗生素耐药基因的因素及抗生素耐药基因的作用机制进行综述,以期推进畜禽肠道微生物耐药基因的相关研究。 展开更多
关键词 畜禽养殖业 抗生素 耐药基因 肠道菌群 耐药性
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MMTV-PyMT乳腺癌小鼠不同周龄肿瘤微环境中免疫细胞的组成变化
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作者 林晓晨 龚丽红 +6 位作者 郭迎雪 金璐 陈梦芸 王鹏皓 余翠 傅惠英 寿旗扬 《中国实验动物学报》 北大核心 2025年第7期935-946,共12页
目的研究不同周龄MMTV-PyMT乳腺癌转基因小鼠的致瘤特性及肿瘤微环境中免疫细胞的组成变化。方法准备8组在4、6、8、10、12、14、16、18周龄的MMTV-PyMT雌性小鼠(以FVB小鼠为背景)以及1组8周龄FVB雌性小鼠,对其血常规进行检测,通过组织... 目的研究不同周龄MMTV-PyMT乳腺癌转基因小鼠的致瘤特性及肿瘤微环境中免疫细胞的组成变化。方法准备8组在4、6、8、10、12、14、16、18周龄的MMTV-PyMT雌性小鼠(以FVB小鼠为背景)以及1组8周龄FVB雌性小鼠,对其血常规进行检测,通过组织病理学切片观察乳腺的病理变化及肺转移情况,通过流式细胞术分析血液、脾、肿瘤中的免疫细胞。结果MMTV-PyMT小鼠4~6周龄时乳腺导管出现腺管样病变,8~9周龄时导管部分长至生长边界,此后逐渐突破腺体边界,在8~12周龄时形成早期乳腺癌,在10~14周龄时出现晚期乳腺癌的特征。在12周龄时部分小鼠肺部分出现可见转移病灶,14周龄肺部转移灶明显增多;随着周龄增长,小鼠血液中白细胞、中性粒细胞、血小板逐渐增多,而淋巴细胞、红细胞则呈逐渐下降趋势;流式细胞术提示随着周龄增长,小鼠脾、肿瘤中T细胞比例逐渐下降,血液、脾、肿瘤中MDSCs逐渐增加,肿瘤中NK细胞也逐渐增加。结论本研究对不同周龄MMTV-PyMT小鼠模型的血常规、病理及组织中的免疫细胞进行分析,为乳腺癌恶性进展过程中肿瘤免疫微环境的动态变化提供新视角。 展开更多
关键词 MMTV-PyMT转基因小鼠 乳腺癌 肺转移 肿瘤微环境
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Clinical Experience of Professor Wei Gunzheng in Treating Pulmonary Heart Disea
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作者 yu cui Gunzheng WEI 《Medicinal Plant》 2025年第3期66-68,共3页
Chronic pulmonary heart disease is a common and frequently occurring condition in the respiratory system.Professor Wei Gunzheng advocates a treatment approach that integrates disease management with syndrome different... Chronic pulmonary heart disease is a common and frequently occurring condition in the respiratory system.Professor Wei Gunzheng advocates a treatment approach that integrates disease management with syndrome differentiation,combining methods to eliminate pathogenic factors and reinforce healthy qi.During acute episodes,the focus should be on expelling pathogenic excess while simultaneously consolidating the root and supporting healthy qi.During remission,the priority shifts to reinforcing the body's vital energy.For effective treatment,it is essential to both tonify deficiency and purge excess,ensuring the elimination of pathogenic factors and the restoration of healthy qi. 展开更多
关键词 Chronic PULMONARY HEART disease SWELLING CONSOLIDATING the root and supporting healthy qi PROFESSOR WEI Gunzhen
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Extraction properties of diglycolamide for rare earth:Contribution of N-substituents
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作者 Xiujing Peng Miaomiao Zhang +5 位作者 Jingjing Yin Heng Zhao Jianhui Su yu cui Xuchuan Jiang Guoxin Sun 《Journal of Rare Earths》 2025年第4期815-821,I0006,共8页
A successful extraction process relies heavily on an excellent extractant structure.The theory of extractant structure and extraction performance is still insufficient to guide the design of new extractants,despite ex... A successful extraction process relies heavily on an excellent extractant structure.The theory of extractant structure and extraction performance is still insufficient to guide the design of new extractants,despite extensive research into extractants.However,diglycolamide extractants have demonstrated certain advantages in nuclear fuel reprocessing and rare earth extraction and separation.This paper focuses on the synthesis of 13 structurally serially changed extractants.There is a good connection between the extraction performance and the energy consumption of the carbonyl conformation torsion of the extractant with symmetrical straight-chain alkyl substituents.The extraction capacity of extractant decreases with the increase of alkyl chain length.The methyl substituent extractant shows higher extractability than the other.The steric effect of the alkyl chain with more than two carbons is not significantly different.The relationship between the structure and performance of extractants was systematically studied by the combination of theoretical calculations and experimental data to investigate the effects of symmetric,asymmetric and branched N-substituents on extraction performance. 展开更多
关键词 N-substituents Structure and performance Diglycolamide extractants EXTRACTION Rare earths
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A strategy for selective extraction of lanthanides based on self-assembly with MPyEDChDGA from nitric acid solution
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作者 Miaomiao Zhang Zhen Yang +5 位作者 Heng Zhao Chengjin Xu Xiaolei Liu Guoxin Sun Xiujing Peng yu cui 《Journal of Rare Earths》 2025年第9期1955-1963,共9页
The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycola... The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements. 展开更多
关键词 Rare earths EXTRACTION SELF-ASSEMBLY SEPARATION HNO_(3)
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利用多重RT-PCR检测进境粮谷中的4种病毒
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作者 张海鹏 黄艳 +6 位作者 于翠 闫晓东 田沂民 华丽 黄铭浩 洪菁 冯黎霞 《植物检疫》 2025年第3期6-14,共9页
本研究旨在建立1种有效而灵敏的方法来同时检测粮谷中玉米褪绿斑驳病毒、小麦线条花叶病毒、玉米矮花叶病毒、高原小麦花叶病毒。选取WSMV L2/R2、MDMV 482F/R、MCMV 384F/R、HPWMoV283F/R分别作为检测小麦线条花叶病毒、玉米矮花叶病... 本研究旨在建立1种有效而灵敏的方法来同时检测粮谷中玉米褪绿斑驳病毒、小麦线条花叶病毒、玉米矮花叶病毒、高原小麦花叶病毒。选取WSMV L2/R2、MDMV 482F/R、MCMV 384F/R、HPWMoV283F/R分别作为检测小麦线条花叶病毒、玉米矮花叶病毒、玉米褪绿斑驳病毒、高原小麦花叶病毒的引物。当退火温度为59℃,延伸温度为66℃,反应体系中玉米褪绿斑驳病毒、小麦线条花叶病毒、玉米矮花叶病毒、高原小麦花叶病毒引物终浓度分别为0.2μmol/L、0.2μmol/L、0.2μmol/L、0.32μmol/L时,达到最好扩增效果。以4种混合阳性病毒质粒为模板开展灵敏度检测,发现其检测限可达1 fg/μL。选取103个测试样品进行检测,检出1种及以上病毒的样品有42个,实现单反应管有效、准确检测4种检疫性病毒,为田间、口岸实验室快速检测鉴定检疫性病毒提供便利。 展开更多
关键词 小麦线条花叶病毒 玉米矮花叶病毒 玉米褪绿斑驳病毒 高原小麦花叶病毒 多重RT-PCR
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High extraction efficiency of N,N,N′,N′-tetracyclohexyldiglycolamide for Sr(Ⅱ):An experimental and crystal structure study
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作者 Xiujing Peng Ling Li +6 位作者 Haiyin yu Riming Hu Jianhui Su Miaomiao Zhang yu cui Xuchuan Jiang Guoxin Sun 《Chinese Journal of Chemical Engineering》 2025年第1期1-9,共9页
To improve the ability of diglycolamide extractants for the extraction of Sr(Ⅱ)from high-level waste liquid,N,N,N′,N′-tetracyclohexyldiglycolamide(TCHDGA)was proposed and studied to extract Sr(Ⅱ)from nitrate media... To improve the ability of diglycolamide extractants for the extraction of Sr(Ⅱ)from high-level waste liquid,N,N,N′,N′-tetracyclohexyldiglycolamide(TCHDGA)was proposed and studied to extract Sr(Ⅱ)from nitrate media.TCHDGA was prepared and characterized by 1H nuclear magnetic resonance spectroscopy(NMR),^(13)C NMR,and fourier transform infrared spectroscopy(FT-IR).Various factors affecting extraction were studied systematically.In just 20 s,the extraction rate can reach approximately 98.2%.The extraction capacity of cyclohexyl-substituted extractant TCHDGA is tens of times higher than that with linear or branched chain alkyl.The chemical structure of the complex has been demonstrated to be[Sr3TCHDGA]·(NO_(3))_(2),based on FT-IR,X-ray photoelectron spectroscopy(XPS),and crystal structure analysis.The crystal belongs to the monoclinic system,space group P21,and a strontium ion coordinates with nine oxygen atoms,all of which contribute from TCHDGA.The stripping rate can reach over 99%when using distilled water or 0.50 mol·L^(-1)oxalic acid as stripping agents. 展开更多
关键词 STRONTIUM TCHDGA extractant EXTRACTION Crystal structure
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Site occupation of Al doping in Lu_(2)SiO_(5):The role of ionic radius versus chemical valence
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作者 Xuejiao Sun yu cui +5 位作者 Feng Gao Zhongjun Xue Shuwen Zhao Dongzhou Ding Fan Yang Yi-Yang Sun 《Chinese Physics B》 2025年第9期344-349,共6页
Lu_(2)SiO_(5):Ce(LSO:Ce)serving as a core material for radiation detectors,plays a crucial role in the design and development of positron emission tomography(PET)devices.Experiment has confirmed that low concentration... Lu_(2)SiO_(5):Ce(LSO:Ce)serving as a core material for radiation detectors,plays a crucial role in the design and development of positron emission tomography(PET)devices.Experiment has confirmed that low concentration of Al doping can significantly enhance the light yield,decay time,rise time,energy resolution,and afterglow level of the LSO:Ce crystals.The mechanisms regarding the lattice site occupancy of Al in LSO,while closely associated with the performance improvements,are not yet fully understood.Particularly,it is unclear either the ionic radius or the chemical valence plays a more critical role in determining the site occupancy.In this study,we utilized first-principles calculations based on density functional theory(DFT)to study the lattice site occupancy of Al in LSO crystals and to explore their impact on the electronic structure.Our results indicate that with changes in the growth environment,as reflected by the atomic chemical potentials,Al can occupy either the Si sites or the Lu_(2)sites,and it is not inclined to occupy the Lu_(1) sites.The doping of Al at the Si site introduces a shallow acceptor level,which may contribute to the suppression of trap concentration and affect the ratio of Ce^(3+)to Ce^(4+)within the crystal,thereby influencing its scintillation properties. 展开更多
关键词 sincitillation materials SILICATES DEFECTS first-principles calculations
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SiC基GaN上多晶金刚石散热膜生长及其影响 被引量:1
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作者 盛百城 刘庆彬 +3 位作者 何泽召 李鹏雨 蔚翠 冯志红 《半导体技术》 CAS 北大核心 2024年第5期455-460,共6页
通过微波等离子体化学气相沉积(MPCVD)法,在SiC基GaN高电子迁移率晶体管(HEMT)异质结构材料上生长多晶金刚石散热膜,采用光学显微镜(OM)、拉曼光谱、非接触霍尔测试系统、X射线衍射(XRD)和扫描电子显微镜(SEM)对生长样品进行表征,研究... 通过微波等离子体化学气相沉积(MPCVD)法,在SiC基GaN高电子迁移率晶体管(HEMT)异质结构材料上生长多晶金刚石散热膜,采用光学显微镜(OM)、拉曼光谱、非接触霍尔测试系统、X射线衍射(XRD)和扫描电子显微镜(SEM)对生长样品进行表征,研究了生长温度、多晶金刚石散热膜厚度对GaN HEMT异质结构材料性能的影响。测试结果表明,当多晶金刚石生长温度为625℃,散热膜厚度为20μm时,GaN材料载流子迁移率降低9.8%,载流子浓度上升5.3%,(002)衍射峰半高宽增加40%。生长温度越高,金刚石散热膜的生长速率越快。当金刚石散热膜厚度相差不大时,生长温度越高,GaN所受拉应力越大,材料电特性衰退越明显。多晶金刚石高温生长过程中,金刚石引入的应力未对GaN结构产生破坏作用,GaN材料中没有出现孔洞等缺陷。 展开更多
关键词 多晶金刚石 散热膜 氮化镓 微波等离子体化学气相沉积(MPCVD)法 电性能 应力 孔洞缺陷
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三维非均匀磁场分布下低场峰产生时的波传播和能量沉积特性分析
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作者 杜丹 胡少雄 +5 位作者 尹陈艳 黄子文 喻翠 杨文军 周华 龚学余 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第12期2462-2477,共16页
考虑粒子碰撞、化学反应和热效应,本文建立了右旋螺旋天线与柱状等离子体相互作用的三维模型,采用有限元法研究了3种三维非均匀磁场分布下右旋螺旋天线放电时的低场峰现象,并分析了密度峰产生时的波传播和功率沉积特性。主要模拟结果表... 考虑粒子碰撞、化学反应和热效应,本文建立了右旋螺旋天线与柱状等离子体相互作用的三维模型,采用有限元法研究了3种三维非均匀磁场分布下右旋螺旋天线放电时的低场峰现象,并分析了密度峰产生时的波传播和功率沉积特性。主要模拟结果表明:在一定磁场大小范围内,随着最大磁场强度增加均存在密度峰现象,低于某阈值(B_(max)<120 G),低场峰产生时多普勒回旋阻尼和异常多普勒回旋阻尼致使的功率沉积占主导地位,且功率沉积峰值分布在螺旋波驻波附近;高于阈值时(B_(max)≥120 G),低场峰产生时碰撞阻尼致使的功率沉积占主导地位。螺旋波左、右旋极化电场同时在等离子体中传播,控制磁场分布,可控制低场峰产生时螺旋波极化电场的幅值、传播性质(行波、驻波、半驻波半行波)、功率沉积、密度和电子温度分布,螺旋波产生的驻波和功率沉积主要分布在磁场强度大的区域。相关研究结果对揭示螺旋波等离子体低场峰机制有一定指导意义。 展开更多
关键词 螺旋波等离子体 低场峰 驻波 功率沉积
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桑树代谢组学研究进展
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作者 张凤 于翠 +3 位作者 董朝霞 朱志贤 胡兴明 张成 《蚕业科学》 CSCD 北大核心 2024年第6期567-576,共10页
代谢组学作为系统生物学的重要组成部分,是继基因组学、转录组学和蛋白组学之后新兴的一门学科,旨在研究生物体生长发育过程中代谢产物的变化规律,揭示机体生命活动代谢的本质,在植物学研究中得到广泛关注。桑树是重要的经济树种,适应... 代谢组学作为系统生物学的重要组成部分,是继基因组学、转录组学和蛋白组学之后新兴的一门学科,旨在研究生物体生长发育过程中代谢产物的变化规律,揭示机体生命活动代谢的本质,在植物学研究中得到广泛关注。桑树是重要的经济树种,适应区域广泛。桑叶、桑椹、桑枝等含有丰富的天然活性代谢产物,具有重要的药理和营养价值。代谢组学为研究桑树不同组织中天然活性代谢产物的积累、桑树适应逆境胁迫的物质基础以及天然活性代谢产物的开发提供了重要的技术方法。本文简要介绍了植物代谢组学研究方法的进展,重点概述了桑树不同组织中代谢组的研究、逆境胁迫下桑树代谢组的研究以及桑树代谢组数据库的研究进展,并展望了桑树代谢组学的应用前景,为桑树天然活性代谢产物的综合利用以及抗逆桑树品种的选育提供参考。 展开更多
关键词 代谢组学 桑树 逆境胁迫 多组学分析
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金刚石固态微波功率器件研究进展和展望
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作者 蔚翠 冯志红 +6 位作者 何泽召 周闯杰 郭建超 马孟宇 余浩 刘庆彬 李鹏雨 《真空电子技术》 2024年第5期47-53,共7页
被誉为终极半导体材料的金刚石具有超宽的禁带宽度、超高击穿电场、高的载流子漂移速率、极高的热导率、极强的抗辐射能力等特性,在微波功率器件领域具有很好的应用前景。金刚石微波功率器件的研究近几年引起了广泛关注,文章总结了金刚... 被誉为终极半导体材料的金刚石具有超宽的禁带宽度、超高击穿电场、高的载流子漂移速率、极高的热导率、极强的抗辐射能力等特性,在微波功率器件领域具有很好的应用前景。金刚石微波功率器件的研究近几年引起了广泛关注,文章总结了金刚石微波功率器件的研究进展,重点分析了目前主流的氢终端金刚石、表面氧化物终端金刚石和掺杂金刚石实现的微波功率器件的研究进展、面临问题和发展展望。 展开更多
关键词 金刚石 晶体管 电性能 功率 表面终端
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The Path Analysis of Farmers' Income Structure in Yunnan Province
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作者 Yongtian XIAO yu cui Lijia HU 《Asian Agricultural Research》 2015年第2期47-49,共3页
The problem of farmers' income growth is the key of issues concerning agriculture,countryside and farmers,so the farmers' income growth is the fundamental starting point for agricultural and rural economic dev... The problem of farmers' income growth is the key of issues concerning agriculture,countryside and farmers,so the farmers' income growth is the fundamental starting point for agricultural and rural economic development. In this paper,we use the statistics concerning farmers' income in Yunnan Province from 1995 to 2012,to perform the path analysis of components of farmers' income in Yunnan Province,study the path of influence of components of farmers' income on farmers' net income,and then set forth the policy recommendations for increasing farmers' income in Yunnan Province. 展开更多
关键词 YUNNAN Province Farmers’ INCOME STRUCTURE Path ANA
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氢终端金刚石薄膜生长及其表面结构 被引量:2
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作者 马孟宇 蔚翠 +3 位作者 何泽召 郭建超 刘庆彬 冯志红 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第8期323-328,共6页
氢终端金刚石的导电性问题是目前限制其在器件领域应用的关键因素.传统的氢终端金刚石制备工艺由于金刚石中含有杂质元素以及表面的加工损伤的存在,限制了氢终端金刚石的电特性.在金刚石衬底上直接外延一层高纯、表面平整的氢终端金刚... 氢终端金刚石的导电性问题是目前限制其在器件领域应用的关键因素.传统的氢终端金刚石制备工艺由于金刚石中含有杂质元素以及表面的加工损伤的存在,限制了氢终端金刚石的电特性.在金刚石衬底上直接外延一层高纯、表面平整的氢终端金刚石薄膜成为一种可行方案,但该方案仍存在薄膜质量表征困难,表面粗糙度较大等问题.本文采用微波等离子体化学气相沉积(CVD)技术,在含氮CVD金刚石衬底上外延一层亚微米级厚度金刚石薄膜,并研究分析了不同甲烷浓度对金刚石薄膜生长以及导电性能的影响.测试结果显示:金刚石薄膜生长厚度为230—810 nm,且外延层氮浓度含量低于1×10^(16) atom/cm^(3),不同的甲烷浓度生长时,金刚石外延层表面出现了三种生长模式,这主要与金刚石的生长和刻蚀作用相关.经过短时间生长后的金刚石薄膜表面为氢终端(2×1:H)结构,而氧、氮元素在其中的占比极低,这使得生长后的金刚石薄膜具有P型导电特性.霍尔测试结果显示,甲烷浓度为4%条件下生长的氢终端金刚石薄膜导电性最好,其方块电阻为4981Ω/square,空穴迁移率为207 cm^(2)/(V·s),有效地提升了氢终端金刚石电特性,为推进大功率金刚石器件发展应用起到支撑作用. 展开更多
关键词 氢终端金刚石 甲烷浓度 生长模式 电性能
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局部制冷降温技术在井下长距离掘进中的应用 被引量:1
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作者 郭忠磊 崔嵛 王春龙 《黄金科学技术》 CSCD 北大核心 2024年第5期916-925,共10页
为解决玲珑金矿深部长距离掘进巷道的高温问题,结合井下低温涌水条件,通过对输冷方式和换热方式进行分析,制定了以水源热泵技术为基础的局部制冷降温技术方案,采用理论计算和模拟仿真方法,模拟不同供风温度和供风量条件下巷道的温度场... 为解决玲珑金矿深部长距离掘进巷道的高温问题,结合井下低温涌水条件,通过对输冷方式和换热方式进行分析,制定了以水源热泵技术为基础的局部制冷降温技术方案,采用理论计算和模拟仿真方法,模拟不同供风温度和供风量条件下巷道的温度场变化情况,分析得出了最佳制冷参数,并开展了制冷系统的设备选型和现场应用。结果表明:-750 m中段长距离掘进工作面的制冷最佳温度为10℃,供风量为5.0 m3/s;根据制冷方案和制冷参数分析结果对局部制冷降温技术进行了应用,有效解决了系统供水不足和供风沿途冷损大等难题,掘进工作面温度由37.0℃降至26.2℃,降幅达10.8℃,距工作面50 m范围内运输巷道温度平均降幅分别为8.9℃和2.9℃,掘进巷高温环境得到明显改善。该局部制冷通风降温技术的应用对类似矿山的深部热害治理具有技术参考价值。 展开更多
关键词 矿业工程 深井 热害 长距离掘进 局部制冷降温技术 玲珑金矿
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进境荷兰风信子种球中Dickeya dadantii subsp.dadantii分离和鉴定 被引量:1
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作者 徐飞 龚静如 +3 位作者 于翠 马丁 张卫东 易建平 《植物检疫》 2024年第3期26-33,共8页
从荷兰进境风信子种球软腐症状组织处分离到一株分离物2018-5,对分离物进行PCR检测、荧光PCR检测、16SrRNA序列分析、多位点序列分析和致病性测试。分离物在NA平板上菌落淡黄褐色,扁平,圆形,边缘不规则。测试结果表明,常规PCR和荧光PCR... 从荷兰进境风信子种球软腐症状组织处分离到一株分离物2018-5,对分离物进行PCR检测、荧光PCR检测、16SrRNA序列分析、多位点序列分析和致病性测试。分离物在NA平板上菌落淡黄褐色,扁平,圆形,边缘不规则。测试结果表明,常规PCR和荧光PCR检测均为阳性;16SrRNA、rpoS、rplB、recA、purA、gapA、gyrA、fusA、dnaX序列和达旦提狄克氏菌达旦提亚种(Dickeya dadantii subsp.dadantii)菌株NCPPB898(CP023467)的序列相似性分别为99.93%,99.55%,100%,95.68%,99.35%,99.34%,99.37%,99.86%,99.59%;基于8个看家基因(rpoS、rplB、recA、purA、gapA、gyrA、fusA和dnaX)的系统发育树显示,分离物2108-5与Dickeya dadantii subsp.dadantii处于同一分支;人工接种风信子叶片和甘薯幼茎都能引起腐烂反应。根据试验结果将分离物2018-5鉴定为达旦提狄克氏菌达旦提亚种(Dickeya dadantii subsp.dadantii)。 展开更多
关键词 风信子 种球 Dickeya dadantii subsp.dadantii 鉴定
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Corrosion Behavior of Pre-oxidized GH4169 Alloy with Solid NaCI Deposited in a Wet Oxygen Flow at 600 ℃
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作者 Weidong Zhang yu cui +4 位作者 Li Liu Wenquan Wang Wenzheng Chen Rui Li Fuhui Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第7期1249-1264,共16页
The corrosion behavior of the pre-oxidized GH4169 alloy was studied after 20 h of exposure under a solid NaCl deposit film in a wet O_(2) environment at 600℃ by mass-gain measurements,X-ray diffraction,scanning elect... The corrosion behavior of the pre-oxidized GH4169 alloy was studied after 20 h of exposure under a solid NaCl deposit film in a wet O_(2) environment at 600℃ by mass-gain measurements,X-ray diffraction,scanning electron microscopy,transmission electron microscopy methods.The results indicate that the pre-oxidized GH4169 alloy undergoes serious corrosion in the corrosive condition.The preformed Cr_(2)O_(3) layer is gradually destroyed by deposit NaCl,and the inner Nb2O5 layer beneath the complete outer Cr_(2)O_(3) layer also reacts with NaCl to form NaNbO_(3).The electrochemical test results testified the existence of electrochemical reactions during this corrosion process.The corrosion behavior of pre-oxidized GH4169 under a solid NaCl deposit film in a wet O_(2) environment at 600℃has been discussed in detail. 展开更多
关键词 PRE-OXIDATION Solid NaCl Wet O2 Electrochemical corrosion
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Strategies for improving extraction capacity through preorganization structure:A novel 5,6-bicyclicmalonamide extractant(THPPD)
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作者 Miaomiao Zhang Zhen Yang +7 位作者 yuhua cui Jianhui Su Heng Zhao Chengjin Xu Xiaolei Liu Guoxin Sun Xiujing Peng yu cui 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第4期768-774,共7页
Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing challenge.Herein,a new strategy was proposed to improve the stability of the che... Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing challenge.Herein,a new strategy was proposed to improve the stability of the chelating structure formed by malonamide and REEs.The stability of the chelating structure is greatly improved by using a double-ring framework structure which makes the two carbonyl groups of malonamide unable to rotate freely and both of them point to the metal ion position.Three benzyl groups were used to construct the hydrophobicity of the extractant and the organic shell of the extracted species.Tribenzylhexahydro-pyrrolo-pyridine-dione(THPPD)was designed and synthesized.The structure reduces the energy consumed by rotating carbonyl group in the coordination with metal ions and then improves the extraction ability of extractant.The crystal structure was preorganized as expected,with the two carbonyls pointing in a favorable coordination direction to the structural complement of the metal ion.The extraction behaviors of REEs with THPPD in a nitric acid medium were studied.Compared with N,N’-dibenzyl-N,N’-dimethylmalonamide(DBDM-MA)with a chain structure,the extraction capacity of THPPD is 360 times higher than that of DBDM-MA at 5.0 mol/L sodium nitrate.Furthermore,the binding energy and Gibbs free energy were investigated by density functional theory(DFT)in conjunction with the B3LYP.The theoretical results show that THPPD has more effective interaction with Pr(NO_(3))3 than DBDM-MA.The construction of chelating groups conformation is a worthy direction to improve the coordination ability and even selectivity of extractant. 展开更多
关键词 Rare earth elements Extraction separation 5 6-bicyclicdiamide extractant
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Psychological stress impact neurotrophic factor levels in patients with androgenetic alopecia and correlated with disease progression
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作者 Yi Cheng Li-Jing Lv +3 位作者 yu cui Xiao-Mei Han Yan Zhang Cai-Xia Hu 《World Journal of Psychiatry》 SCIE 2024年第10期1437-1447,共11页
BACKGROUND Androgenetic alopecia(AGA)is a common form of hair loss that can be influenced by psychological factors.AIM To investigate the impact of mental stress on neurotrophic factors in patients with AGA and correl... BACKGROUND Androgenetic alopecia(AGA)is a common form of hair loss that can be influenced by psychological factors.AIM To investigate the impact of mental stress on neurotrophic factors in patients with AGA and correlate the findings with the progression of AGA.METHODS A total of 120 patients with AGA were analyzed in this study,which were divided into a non-stress group(n=30)and a stress group(n=90)on the basis of the presence or absence of psychological stress confirmed by Depression Anxiety Stress Scale-21 scale.The baseline demographic characteristics,serum cortisol levels,hair growth parameters,neurotrophic factors,and AGA progression scores between the non-stress and stress groups were compared.Correlation analyses were conducted to assess the relationships among stress,neurotrophic factors,hair loss progression,and AGA progression.RESULTS This study revealed significantly higher cortisol levels throughout the day in the stress group than in the non-stress group.The stress group exhibited lower levels of nerve growth factor,brain-derived neurotrophic factor,and glial cell linederived neurotrophic factor and higher expression levels of neurotrophin(NT)-3 and NT-4 than the non-stress group.Hair parameters indicated lower hair diameter,decreased hair density,and more severe AGA grading in the stress group,whereas follicle count and terminal/vellus hair ratio showed no significant differences between the two groups.After 1 year of treatment with 5%minoxidil,efficacy was observed to be lower but AGA progression was notably more pronounced in the stress group than in the non-stress group.Disease progression was positively correlated with high stress and NT-4 levels.CONCLUSION This study provides compelling evidence of the influence of mental stress on neurotrophic factors and its correlation with the progression of AGA.The findings underscore the need for a comprehensive approach to the management of AGA that considers the physiological and psychosocial aspects.Further research is warranted to validate the findings and explore targeted therapeutic interventions for individuals with stress-related AGA. 展开更多
关键词 Mental stress Neurotrophic factors Androgenetic alopecia PROGRESSION
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进口高粱中3种检疫性病毒的检测
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作者 陈红运 廖富荣 +4 位作者 陈青 叶明辉 冯黎霞 于翠 王秀芬 《植物检疫》 2024年第5期26-30,共5页
本研究以进口高粱为材料,采用一步法RT-PCR检测玉米褪绿斑驳病毒(maize chlorotic mottle virus,MCMV)、玉米矮花叶病毒(maize dwarf mosaic virus,MDMV)和小麦线条花叶病毒(wheat streak mosaic virus,WSMV)。23份高粱样品中,2份检出MC... 本研究以进口高粱为材料,采用一步法RT-PCR检测玉米褪绿斑驳病毒(maize chlorotic mottle virus,MCMV)、玉米矮花叶病毒(maize dwarf mosaic virus,MDMV)和小麦线条花叶病毒(wheat streak mosaic virus,WSMV)。23份高粱样品中,2份检出MCMV,5份检出MDMV,19份样品检出WSMV。1份样品检出MCMV、MDMV和WSMV,4份样品检出MDMV和WSMV。综合前期和本研究结果,建议将MCMV-F7/MCMV-R7、MDMV482F/MDMV482R和WSMV-F3/WSMV-R3作为3种检疫性病毒的首选检测引物,MCMV-2452F/MCMV-3111R、3MDF/1MDR和WSMV-1F/WSMV-3R作为备选,引物3MDF/1MDR用于鉴定MDMV分离物的分支归属。 展开更多
关键词 玉米褪绿斑驳病毒 玉米矮花叶病毒 小麦线条花叶病毒 检测
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