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Chemical Modification of Tryptophan Residues in Superoxide Dismutase from Camellia Pollen and Its Fluorescence Spectrum

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Chemical Research in Chinese Universities 2005年第5期21卷 562-565页

作者： HE Xiao-hong WU Min LI Shan-yu chu yu-zhuo CHEN Jia LIU Lan-ying College of Life Science Jilin University Changchun 130023 P. R. China

The amino acid composition of the superoxide dismutase（SOD） from camellia pollen was measured and the tryptophan（Trp） residues were modified by using N-bromosuccinimide（NBS）. The results show that there are 21 Trp residues in an SOD molecule and seven of which are located on the surface of the enzyme. By researching the fluorescence spectra of the native SOD and the modified SOD, we have found that the emission wavelength of Trp is at 335 nm and the fluorescence intensity will decrease when the enzyme is modified. The results also show that potassium iodide（KI） can significantly quench the fluorescence of the native SOD, but it has a less pronounced effect on the modified enzyme. Glycerin as a surface activation reagent can stabilize the fluorescence of the modified enzyme.

关键词： Superoxide dismutase Tryptophan residue Chemical modification Fluorescence spectrum

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透明质酸酶的色氨酸残基修饰与荧光光谱研究

高等学校化学学报 2005年第9期26卷 1662-1664页

作者：滕利荣初宇卓张晓萍王静韩松于笑坤刘兰英吉林大学生命科学学院长春130023

Tryptophan residues in Hyaluronidase(HAase) were modified by N-bromosuccinimide(NBS). The results indicated that there were eleven tryptophan residues in HAase and one of them was exposed, which was proved to be essential for the activity of the enzyme. The study on fluorescence quenching of HAase showed that KI could not quench all of the fluorescence from Trp residues in HAase . Acrylamide(Acr), a polarized quencher without electronic charge, could quench almost all of the fluorescence from Trp residues in HAase . The collisional quenching constants(K-D) of HAase at different concentrations of Acr were calculated in terms of Stern-Volmer equation. The results implied that some of Trp residues were buried in the interior of HAase, and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.

关键词：透明质酸酶色氨酸残基化学修饰荧光猝灭

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi Song Ruixin Li Xiaolei chu Qi Li Ruihua Li Qingwen Li Kai-yu Tong Xiaosong Gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe Laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach

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刺五加多糖的提取及其抗氧化性

吉林大学学报（理学版） 2005年第5期43卷 683-686页

作者：孟庆繁于笑坤徐睦芸李明亮高智慧范豪初宇卓滕利荣吉林大学生命科学学院长春130012

用热水浸提法提取刺五加多糖,用乙醇对其分级沉淀,当乙醇的体积为提取液的1倍时,多糖沉淀量最大,随着乙醇用量增加,各级产物减少,其多糖的总收率为原刺五加质量的0.54%.用邻苯三酚法及fenton体系测定各分级产物对O2-和.OH的抑制作用,随... 详细信息

用热水浸提法提取刺五加多糖,用乙醇对其分级沉淀,当乙醇的体积为提取液的1倍时,多糖沉淀量最大,随着乙醇用量增加,各级产物减少,其多糖的总收率为原刺五加质量的0.54%.用邻苯三酚法及fenton体系测定各分级产物对O2-和.OH的抑制作用,随着乙醇用量增加,其产物的抗氧化能力增强,当乙醇用量是提取液体积的6倍时,其产物对O2-的清除率最大可达47.7%;当乙醇用量达4倍时,其产物对.OH的清除率最大达68.2%.刺五加多糖对红细胞膜脂质过氧化的抑制作用随糖浓度的增加而加大,当多糖浓度在0.4 g/L以上时,不仅H2O2对红细胞膜的氧化作用完全被抑制,而且对红细胞膜产生还原作用.

关键词：刺五加多糖提取生物活性

Controllable Synthesis of CaCO_3 Micro/Nanocrystals with Different Morphologies in Microemulsion

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Chemical Research in Chinese Universities 2010年第5期26卷 678-682页

作者： yu Dong chu Ying DONG Li-hong zhuo yu-jiang Department of Chemistry Northeast Normal University Changchun 130024 P. R. China Elementary Normal College Dalian University Dalian 116300 P. R. China

Lens-like vaterite CaCO3 microrings composed of CaCO3 nanoparticles were synthesized via a microemulsion-mediated route at room temperature with ethanol and n-hexanol as co-surfactant. This process did not demand any additional energy such as heating or continuous agitation. It was the first time to use ethanol as co-surfactant in the synthesis of micro or nanomaterials. And the ethanol was believed to play an important role in the aggregation fashion of CaCO3 nanoparticles. Moreover, shuttle-shaped nanorods, hexagonal nanoplates, and rice-like nanoparticles were also fabricated by modulating the growth parameters. Additionally, the introduce of ethanol into microemulsions as co-surfactant may be generalized as a novel green route to control the structure of other functional materials.

关键词： CaCO3 Microring Cosurfactant

Maximum Principle of Optimal Stochastic Control with Terminal State Constraint and Its Application in Finance

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Journal of Systems Science & Complexity 2018年第4期31卷 907-926页

作者： zhuo yu Department of Finance and Control Sciences School of Mathematical Sciences Fudan University

This paper considers the optimal control problem for a general stochastic system with general terminal state constraint. Both the drift and the diffusion coefficients can contain the control variable and the state constraint here is of non-functional type. The author puts forward two ways to understand the target set and the variation set. Then under two kinds of finite-codimensional conditions, the stochastic maximum principles are established, respectively. The main results are proved in two different ways. For the former, separating hyperplane method is used; for the latter, Ekeland＇s variational principle is applied. At last, the author takes the mean-variance portfolio selection with the box-constraint on strategies as an example to show the application in finance.

关键词： Finite-codimensional condition mean-variance portfolio selection problem stochastic maximum principle terminal state constraint.

Nanomedicine-based multimodal therapies:Recent progress and perspectives in colon cancer

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World Journal of Gastroenterology 2023年第4期29卷 670-681页

作者： yu-chu He Zi-Ning Hao zhuo Li Da-Wei Gao State Key Laboratory of Metastable Materials Science and Technology Nano-Biotechnology Key Laboratory of Hebei ProvinceApplying Chemistry Key Laboratory of Hebei ProvinceYanshan UniversityQinhuangdao 066000Hebei ProvinceChina

Colon cancer has attracted much attention due to its annually increasing *** chemotherapeutic drugs are unsatisfactory in clinical application because of their lack of targeting and severe toxic side *** the past decade,nanomedicines with multimodal therapeutic strategies have shown potential for colon cancer because of their enhanced permeability and retention,high accumulation at tumor sites,co-loading with different drugs,and combination of various *** review summarizes the advances in research on various nanomedicine-based therapeutic strategies including chemotherapy,radiotherapy,phototherapy(photothermal therapy and photodynamic therapy),chemodynamic therapy,gas therapy,and ***,the therapeutic mechanisms,limitations,improvements,and future of the above therapies are discussed.

关键词： Colon cancer Nanomedicine Drug permeability Drug retention Multimodal therapies Therapeutic mechanism

Powell dynamic identification of displacement parameters of indeterminate thin-walled curve box based on FCSE theory

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Acta Mechanica Sinica 2011年第3期27卷 452-460页

作者： Jian Zhang chu-Wei Zhou Jia-Shou zhuo College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics 210016 Nanjing China College of Mechanics and Material Hohai University 210098 Nanjing China

The FCSE controlling equation of pinned thinwalled curve box was derived and the indeterminate problem of continuous thin-walled curve box with diaphragm was solved based on flexibility theory. With Bayesian statistical theory,dynamic Bayesian error function of displacement parameters of indeterminate curve box was founded. The corresponding formulas of dynamic Bayesian expectation and variance were deduced. Combined with one-dimensional Fibonacci automatic search scheme of optimal step size,the Powell optimization theory was utilized to research the stochastic identification of displacement parameters of indeterminate thin-walled curve box. Then the identification steps were presented in detail and the corresponding calculation procedure was compiled. Through some classic examples,it is obtained that stochastic performances of systematic parameters and systematic responses are simultaneously deliberated in dynamic Bayesian error function. The one-dimensional optimization problem of the optimal step size is solved by adopting Fibonacci search method. And the Powell identification of displacement parameters of indeterminate thin-walled curve box has satisfied numerical stability and convergence,which demonstrates that the presented method and the compiled procedure are correct and *** parameters鈥？iterative processes,the Powell theory is irrelevant with the calculation of finite curve strip element（FCSE） partial differentiation,which proves high computation effciency of the studied method.

关键词： Powell theory - Indeterminate curve box . Displacement parameters - Fibonacci search method.Flexibility theory

Relative Broken Family Sensitivity

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2297-2306页

作者： zhuo Wei LIU Tao yu Department of Mathematics Shantou UniversityShantou 515063P.R.China

Letπ:(X,T)→(Y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of *** introduce the notion of relative broken *** Fs(***,Finf)be the families consisting of all syndetic subsets(*** upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(Y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not *** a factor mapπ:(X,T)→(Y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor.

关键词： Relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor