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龟羚帕安丸对帕金森病大鼠神经干细胞移植后中脑黑质TH、GDNF、Ptx3表达的影响

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中成药 2018年第8期40卷 1681-1686页

作者：常学辉张良芝黎民河南中医药大学第二临床医学院河南郑州450002 河南中医药大学基础医学院河南郑州450008

目的观察龟羚帕安丸对帕金森病大鼠神经干细胞移植后中脑黑质TH、GDNF、Ptx3表达的影响。方法 6-羟基多巴注射法建立帕金森病模型后,60只造模大鼠随机分为空白对照组,美多芭组,龟羚帕安丸高、中、低剂量组,神经干细胞移植组,各组灌胃给... 详细信息

目的观察龟羚帕安丸对帕金森病大鼠神经干细胞移植后中脑黑质TH、GDNF、Ptx3表达的影响。方法 6-羟基多巴注射法建立帕金森病模型后,60只造模大鼠随机分为空白对照组,美多芭组,龟羚帕安丸高、中、低剂量组,神经干细胞移植组,各组灌胃给药2. d。然后,免疫组化法检测大鼠中脑黑质TH、GDNF、Ptx3蛋白表达,原位杂交法检测TH mRNA表达。结果与神经干细胞移植组比较,美多芭组、龟羚帕安丸组TH、GDNF、Ptx3蛋白及TH mRNA表达均显著增加(P<0.01)。结论龟羚帕安丸可增加帕金森病大鼠中脑黑质TH、GDNF、Ptx3蛋白表达,可能是其治疗帕金森病的作用机制之一。

关键词：龟羚帕安丸帕金森病神经干细胞移植中脑黑质 TH GDNF Ptx3

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大孔树脂富集多舌飞蓬总咖啡酸酯的工艺

精细化工 2017年第2期34卷 186-190,240页

作者：王凯顺袁慕华刘璇赵野张志锋西南民族大学药学院四川成都610041 西南民族大学青藏高原研究院四川成都610041

考察了13种不同极性的大孔吸附树脂对多舌飞蓬中总咖啡酸酯的富集纯化能力,发现极性树脂NKA-2.静态吸附率为92.51%、解吸率为98.51%,明显优于其他树脂。进一步以NKA-2.性树脂对多舌飞蓬总咖啡酸酯进行静态吸附与动态吸附实验,结果表明... 详细信息

考察了13种不同极性的大孔吸附树脂对多舌飞蓬中总咖啡酸酯的富集纯化能力,发现极性树脂NKA-2.静态吸附率为92.51%、解吸率为98.51%,明显优于其他树脂。进一步以NKA-2.性树脂对多舌飞蓬总咖啡酸酯进行静态吸附与动态吸附实验,结果表明,最佳上样质量浓度为300 g/L,最佳上样流速为2.BV/h(BV/h即每小时内,通过床层液体体积的倍数),树脂吸附容量为6 m L/g,即每克NKA-2.脂可以处理1.8 g生药。解吸实验结果表明,用体积分数为60%的乙醇水溶液洗脱,洗脱剂用量为30 m L/g树脂。用上述条件对多舌飞蓬总咖啡酸酯富集纯化,使总咖啡酸酯的纯度由18.09%提高到58.06%,回收率高达94.78%。说明NKA-2.大孔吸附树脂综合性能良好,可用于多舌飞蓬中总咖啡酸酯成分的富集和纯化。

关键词：多舌飞蓬大孔树脂总咖啡酸酯纯化工艺吸附动力学特征

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不同溶质溶液对氢棒产氢速率的影响

军事医学 2017年第10期41卷 835-840页

作者：张苗李志慧张成岗安徽医科大学合肥230032 军事医学科学院放射与辐射医学研究所蛋白质组学国家重点实验室全军军事认知与心理卫生研究中心北京100850

目的比较氢棒在不同溶质溶液中的产氢速率,并明确溶液中氢和含氧量的相关性以及氢与氧化还原电位的关系。方法采用含有金属镁的氢棒与水反应产氢的方法制备富氢溶液,具体分为:NaCl、Na_2.O_3、Na_2.O_4、CH_3COOH和CH_3COONa溶液组,分... 详细信息

目的比较氢棒在不同溶质溶液中的产氢速率,并明确溶液中氢和含氧量的相关性以及氢与氧化还原电位的关系。方法采用含有金属镁的氢棒与水反应产氢的方法制备富氢溶液,具体分为:NaCl、Na_2.O_3、Na_2.O_4、CH_3COOH和CH_3COONa溶液组,分别配制0%、0.2.、0.9%和3%的不同浓度上述溶液,并依次分别在0、2.4、6、8、10h后测定各溶液的含氢量、含氧量、氧化还原电位和pH值。结果在制备时间相同时,NaCl溶液浓度越高其产氢速率越高。溶液中氢气与氧气的含量呈显著负相关(R^2.0.9306),含氢量越高含氧量越低;溶液中随含氢量的增加氧化还原电位逐渐降低,而pH值则逐渐升高。在不同溶质溶液中,氢棒的产氢速率顺序为Na_2.O_3>NaCl>Na_2.O_4(P<0.05或P<0.01)。在乙酸溶液中,与钠盐溶液相比,其氢棒的产氢速率显著高于钠盐溶液(P<0.05),含氢量随时间延长而逐渐增加;氧浓度显著低于钠盐溶液(P<0.05),含氧量随时间增加逐渐减少。结论溶液中溶质的种类和浓度以及溶液的含氧量和酸碱度对氢棒的产氢速率具有显著影响,提示可通过调整溶液中溶质的种类和浓度,制备所需要的不同氢浓度含量的富氢溶液,为氢棒制氢在临床以及日常生活中的应用提供参考依据。

关键词：氢棒溶质溶液产氢速率含氢量含氧量氢浓度氧化还原

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秦艽多糖体外抗肿瘤的量效与时效关系研究

安徽科技学院学报 2017年第3期31卷 43-47页

作者：黄虹芝肖平南京瑞东医院江苏南京210033 南京中医药大学江苏南京210023

目的:研究秦艽多糖的体外抗肿瘤活性。方法:采用MTT法研究秦艽多糖在不同浓度和时间条件下,对人肝癌细胞SMMC7402.人胃癌细胞BGC-803、人肺癌细胞A549、人肾癌细胞HEK2.3的抑制作用。结果:秦艽多糖对人肝癌细胞SMMC7402.人肺癌细胞A54... 详细信息

目的:研究秦艽多糖的体外抗肿瘤活性。方法:采用MTT法研究秦艽多糖在不同浓度和时间条件下,对人肝癌细胞SMMC7402.人胃癌细胞BGC-803、人肺癌细胞A549、人肾癌细胞HEK2.3的抑制作用。结果:秦艽多糖对人肝癌细胞SMMC7402.人肺癌细胞A549抑制作用明显,但对人胃癌细胞BGC-803、人肾癌细胞HEK2.3的抑制作用较弱;秦艽多糖对4种肿瘤细胞的抑制作用表现出一定的量效关系及时效关系。结论:秦艽多糖具有较好的体外抗肿瘤活性。

关键词：秦艽多糖抗肿瘤活性量效关系时效关系

Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： zhi-Hua ZHOU zhi-Hao TAN National Key Laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/*** research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in *** prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon *** article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

Graphdiyne(C_(n)H_(2.-2.)as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2.S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li Jing-zhi Wang zhi-Liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2.inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2.,which increases the number of active *** ternary composite catalyst 2.%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2.(2.-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2.,*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for2. h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

P-symmetric Subharmonic Solutions for Nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： Duan zhi ZHANG zhi Hao ZHAO School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a *** the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2. are geometrically distinct for k_(1)/k_(2.≥(2.+1)m+1;and xk_(1),xk_(2. are geometrically distinct for k_(1)/k_(2.≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear

Enhanced memristor performance via coupling effect of oxygen vacancy and ferroelectric polarization

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Journal of Materials Science & Technology 2024年第4期171卷 139-146页

作者： zhi Yun Yue zhi Dong Zhang Zhan Jie Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

As a new type of nonvolatile memory,the resistive memristor has broad application prospects in in-formation storage and neural computing based on its excellent resistive switching(RS)*** present,it is still a great challenge to improve both ferroelectric polarization and leakage current to achieve a high RS on/offratio of ferroelectric ***,epitaxial Pb(Zr_(0.40)Ti_(0.60))O_(3)(PZT)thin films with low content Ca doping were deposited on the Nb:SrTiO_(3)substrate to prepare PCZT/NSTO het-erostructures and their RS behaviors were *** research findings show that compared with pure PZT film,the ferroelectric polarization of 1-mol%-Ca-doped PZT film is slightly improved,while the leak-age current is increased by three orders of ***,the RS on/offratio reaches 2.5×10^(5),about three orders of magnitude higher than pure PZT *** theoretical analysis reveals that the RS behavior of PCZT/NSTO heterostructures is controlled by the PCZT/NSTO interfacial barrier and the space charge-limited current *** results demonstrate that the ferroelectricity and electricity of ferroelectric thin films can be improved simultaneously by doping low-content Ca ions to increase the RS performance,which provides a good reference for the development of high-performance ferroelectric memristor devices.

关键词： Ferroelectric memristor Ca-doped PZT Ferroelectric polarization Oxygen vacancies Resistive switching

Mixed Dead-time Effect Suppression Strategy for Modular Multilevel Converters

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1075-1084页

作者： zhi Geng Minxiao Han School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China IEEE

Dead time is necessary for the coupled power switches to prevent shoot-through,especially in the modular multilevel converters(MMCs)with a large number of power *** paper proposes a dead-time effect suppression strategy for MMCs with nearest level *** operational principles of MMCs are first *** to the operational features of MMCs,the method that removes a switching signal from the coupled switches and the reduced switching frequency voltage balancing algorithms(RSFVBAs)are mixed in the proposed *** the intervals that are furthest away from the zerocrossing points(ZCP)of arm currents,the single switching signal method can completely eliminate the dead-time effect(DTE).Alternatively,the DTE is suppressed by the RSFVBA in intervals that are close to the *** the combination of the two methods,the dependence of the DTE suppression method on currents is reduced and the influences of ZCP are also released without degrading the normal operation performance of ***,the output performance of MMCs is improved and the voltage stress on the arm inductor dramatically ***,the validation of the method is verified by the simulation results with the professional tool Matlab/Simulink.

关键词： Dead-time effect modular multilevel converters switching frequency voltage balancing algorithm