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金果榄质量HPLC评价研究

中国新药杂志 2024年第4期33卷 400-406页

作者：陈帅袁崇均罗森汤依娜向缅周先建王笳杨玉霞四川省中医药科学院成都610041 中药材品质及创新中药研究四川省重点实验室成都610041

目的:建立同时测定金果榄药材中古伦宾、蜕皮激素和生物碱类成分的含量的方法,并寻找金果榄药材中的质量差异标志物。方法:采用HPLC法同时测定古伦宾、蜕皮激素、非洲防己碱、药根碱和巴马丁的含量,并以检测出的含量为指标,结合聚类分... 详细信息

目的:建立同时测定金果榄药材中古伦宾、蜕皮激素和生物碱类成分的含量的方法,并寻找金果榄药材中的质量差异标志物。方法:采用HPLC法同时测定古伦宾、蜕皮激素、非洲防己碱、药根碱和巴马丁的含量,并以检测出的含量为指标,结合聚类分析和偏最小二乘判别分析进一步确定金果榄药材中的质量差异标志物。结果:测定方法精密度、稳定性和重复性良好,聚类分析和偏最小二乘判别分析结果均显示20批样品可分为三大类,变量权重结果证实非洲防己碱、古伦宾、巴马汀为金果榄药材主要质量差异标志物。结论:所建方法利用DAD检测器特性,同时监测多个波长,方便快捷,能显著提高药材质量控制效率;聚类分析和偏最小二乘判别分析结果也可为金果榄药材种植、栽培提供依据。

关键词：金果榄古伦宾蜕皮激素非洲防己碱药根碱巴马丁聚类分析偏最小二乘判别分析

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微生物产胞外多糖研究进展

粮油食品科技 2024年第5期32卷 169-176页

作者：李佳欣杨玉霞陶然崔进喜毛鹏赵秀红沈阳师范大学粮食学院辽宁沈阳110034 沈阳师范大学校园安全与管理处辽宁沈阳110034

近年来,微生物产胞外多糖(EPS)因能改善食品质量、调节肠道菌群、抗氧化、抗肿瘤、免疫预防及防治心脑血管疾病的功能特性而受到关注,并通过研究者的逐渐深入研究和各种方法修饰EPS结构,以增强其功能。目前,国内对微生物EPS的研究仍处... 详细信息

近年来,微生物产胞外多糖(EPS)因能改善食品质量、调节肠道菌群、抗氧化、抗肿瘤、免疫预防及防治心脑血管疾病的功能特性而受到关注,并通过研究者的逐渐深入研究和各种方法修饰EPS结构,以增强其功能。目前,国内对微生物EPS的研究仍处于初级阶段,仍需进一步探索。综述了国内外微生物产EPS的分类、生物合成、结构修饰、功能特性及其应用方面的最新进展,分析了不同种类EPS的生物合成途径和结构特点,以及通过物理、化学和生物方法对其进行功能性修饰的策略,为相关领域的研发提供新的参考,促进EPS在食品、医药及工业领域的应用和产业化发展。

关键词：微生物胞外多糖生物合成结构修饰功能特性

Synthesis and anti-HBV activity of S-substituted 7-mercapto-4-methylcoumarin analogs

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Chinese Chemical Letters 2008年第8期19卷 925-927页

作者： Ying Chen Jin Zhou Hai Wang Yi xia Zheng yu yang Peng xia Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China

Twelve S-substituted 7-mercapto-4-methylcoumarin analogs were synthesized and evaluated for the inhibition to HBV in HepG2 2.***.1.5 cell. Among them, ten compounds exhibited potent inhibition to HBsAg and/or HBeAg with the IC50 values of sub μmol/L level. The ICso of anti-HBsAg activities of 5c and 5j reached 0.01 μmol/L respectively which were 16 fold more potent than that of 3TC. Compounds 3, 5e, 5g, 5h and 5i showed admirable inhibitory activity to both HBsAg and HBeAg. The bioassay results indicated the S-substituted 7-mercapto-4-methylcoumarin analogs merit attention as novel anti-HBV agents.

关键词： Synthesis S-Substituted 7-mercapto-4-methylcoumarin Anti-HBV

Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.

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南方农业学报 2024年第8期55卷 2386-2395页

作者： LIANG Xue-lian CHEN Wei JIANG Wen-yan LIAO Jie yang yu-xia WANG Hai-jun LI Hui-ling LU Wei-fan WANG Tian-shun XIE Hong-zhao Agro-products Quality Safety and Testing Technology Research Institute Guangxi Academy of Agricultural SciencesNanningGuangxi 530007China Institute of Agro-products Processing Science and Technology Guangxi Academy of Agricultural SciencesNanningGuangxi 530007China Guangxi Association for Standardization NanningGuangxi 530009China

【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 *** 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),*** *** 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 *** *** root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of *** *** 130.74,78.69 and 56.62 mg/kg(fresh matter),*** of Cd stored in the cell wall and the soluble fractions of the root and leaf of *** Michx.,with only a smaller portion Cd in organelle *** 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 *** concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms *** and protein integrated-Cd was the main chemical forms Cd in the root and leaf of *** Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,*** 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 *** *** strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and

关键词： Aster subulatus Michx. cadmium bioaccumulation chemical form subcellular distribution

Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： yu-Zhao yang Cheng Xu Li-xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

Osthole attenuates pulmonary arterial hypertension by the regulation of sphingosine 1-phosphate in rats

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Chinese Journal of Natural Medicines 2020年第4期18卷 308-320页

作者： YAO Li yang yu-xia CAO Hui REN Huan-Huan NIU Zheng SHI Ling Department of Medicinal Chemistry and Natural Medicine Chemistry Department of PharmacognosyCollege of PharmacyHarbin Medical UniversityHarbin 150081China State-Province Key Laboratory of Biomedicine-Pharmaceutics of China Harbin Medical UniversityHarbin 150081China Department of Pharmacology College of PharmacyHarbin Medical UniversityHarbin 150081China

Osthole is observed to have the capacity to treat pulmonary arterial hypertension(PAH) in rats, but molecular mechanism is still unknown. The present study aims to discover therapeutic targets and explore therapeutic mechanism of osthole against PAH from metabolic perspective. A rat model with PAH was successfully established with MCT, following osthole administration, then untargeted metabolomics assay was performed using UPLC-Q-TOF-MS to identify differential metabolites and associated metabolic pathways, at last mechanism investigation was done by qRT-PCR, Western blot and ELISA. Differential metabolites characterized in rats with PAH were mostly assigned to sphingolipid metabolism, synthesis of unsaturated fatty acids, glycolysis, nucleotide metabolism, steroid hormone biosynthesis. Furthermore, osthole reversed high level of S1 P by modulating metabolic enzyme Sphk1 in rats with PAH. In addition, osthole inhibited the expression of Sphk1 by downregulating microRNA-21, phosphorylation of Akt, phosphorylation of mTOR in vivo and in vitro. These results demonstrated that metabolomics is a promising approach to discover potential drug target for PAH treatment. Importantly, our findings further elucidated therapeutic mechanism of osthole, a natural product, having a role of metabolic regulator to potentially treat PAH by targeting inhibition of Sphk1/S1 P via microRNA-21-PI3 K/Akt/mTOR signal pathway. Altogether, this discovery paves a critical foundation for enabling osthole to be a candidate compound to treat PAH.

关键词： Pulmonary arterial hypertension Osthole Metabolomics Sphk1/S1P MicroRNA-21-PI3K/Akt/mTOR Therapeutic mechanism

A porous Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3) light color adjustable phosphor:Luminescent property and application of warm white LED

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Journal of Rare Earths 2024年第8期42卷 1421-1428,I0001页

作者： yunxiao Ma Chao Linghu Ming yang Hui yu xiangting Dong Long xia School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun130022China School of Materials Science and Engineering Harbin Institute of Technology(Weihai)Weihai264209China

Light emitting diode(LED) is the fourth generation lighting source,but it has some shortcomings such as complex chip packaging process and the unbalanced light color of phosphor in long-time *** this study,a kind of Eu-terephthalic acid/Tb-sulfosalicylate/ZrO_(2)/ZnZrO_(3)(Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3))phosphor with warm white light emission properties was prepared,and the warm white light LED(wWLEDs) was successfully prepared by encapsulating Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3) phosphors together with 270 nm *** ZrO_(2)/ZnZrO_(3),Tb-SSA/ZrO_(2)/ZnZrO_(3) and Eu-PTA/ZrO_(2)/ZnZrO_(3) samples show blue emission,green emission and red emission under deep ultraviolet(UV,270 nm) excitation,*** Tb-SSA and Eu-PTA are co-doped into ZrO_(2)/ZnZrO_(3) matrix with blue emission to achieve the warm white light emission,and the light color can be adjusted by controlling the doping amount of Eu^(3+)-and Tb^(3+).Through the excitation method of single-component phosphor by the single chip,the complex chip packaging process of w-LED can be *** doping rare earth organic complexes into porous ZrO_(2)/ZnZrO_(3) matrix,the problems of the light color unbalanced of phosphor and the low luminescence intensity of rare earth doped metal oxides composites can be solved.

关键词： Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3) Luminescence material Light color adjustable phosphor Warm white emission W-WLEDs Rare earths

Indirect strategies in language learning and teaching

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Sino-US English Teaching 2008年第9期5卷 11-16,33页

作者： yang yu-xia English Department of Social Sciences and Humanities Xi ＂an University of Technology Xi＇an 710048 China

How to learn foreign language effectively is an extremely important topic for both teachers and learners. Learning strategies may play a crucial role in helping learning process What＇s more, indirect learning strategies such as arranging, planning, evaluating, etc. are in some parts quite helpful. This paper provides some indirect learning strategies to both teachers and learners, which aims at arousing teachers and learners＇ attention for their importance and usefulness.

关键词： language learning strategies indirect language learning strategies

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-Jie xia yu Fu Wei Cao Jun Li yang-Gang Wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom