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前边缘皮质神经元自噬功能受损是神经病理性疼痛中焦虑共病的基础

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中国疼痛医学杂志 2024年第5期30卷 370-370页

作者： Fu S Sun hj Wang jX 付苏(译) 刘风雨(校) 不详北京大学神经科学研究所

内侧前额叶皮质(medial prefrontal cortex,mPFC)在慢性疼痛的预测、发展和调控过程中发挥重要作用。其神经可塑性适应不良是慢性神经病理性疼痛与焦虑共病的基础,但其分子和神经元机制尚未阐明。该研究以大鼠坐骨神经分支选择结扎切断(... 详细信息

内侧前额叶皮质(medial prefrontal cortex,mPFC)在慢性疼痛的预测、发展和调控过程中发挥重要作用。其神经可塑性适应不良是慢性神经病理性疼痛与焦虑共病的基础,但其分子和神经元机制尚未阐明。该研究以大鼠坐骨神经分支选择结扎切断(spared nerve injury,SNI)神经病理性疼痛模型为研究对象,观察大鼠在以焦虑样行为为特征的神经病理性疼痛的特定阶段,mPFC的一个核心亚区,前边缘皮质(prelimbic cortex,PrL)的作用。研究者首先发现,在慢性神经病理性疼痛晚期,大鼠出现焦虑样行为并伴有PrL神经元自噬损伤。随后通过带有神经元特异性启动子的腺相关病毒(adeno-associated viral vector,AAV),特异性下调(模拟自噬损伤)及上调PrL神经元内自噬水平(挽救自噬损伤),研究神经元自噬与慢性痛诱发的焦虑样行为的关系。

关键词：神经元自噬神经病理性疼痛慢性痛神经可塑性共病慢性疼痛腺相关病毒大鼠

Luminescence properties of sol-gel derived silica gels doped and undoped with RE-complexes(RE=Eu,Tb)

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Chinese journal of Chemistry 1997年第4期15卷 327-335页

作者： Lin, j Li, B Zhang, hj CHINESE ACAD SCI CHANGCHUN INST APPL CHEMRARE EARTH CHEM & PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The luminescence properties of silica gels and silica gels doped with two rare earth complexes, Eu(TTA)(3) and Tb(o-CBA)(3) (TTA=thenoyltriffuocetate, o-CBA=o-chlorobenzoic acid) are reported and discussed. Pure silica gels show a blue luminescence, and the maximum excitation and emission wavelengths depend strongly on the solvents used. Both of the studied rare earth complexes exhibit the characteristic emissions of the rare earth ions in silica gels, i.e., Eu3+5D0-->F-7(j)(j=0,1,2,3,4), Tb3+5D4-->F-7(j)(j=3,4,5,6) transitions. Compared with the pure RE-complexes powder, the silica gels doped with RE-complexes show fewer emission lines of the rare earth ions. Furthermore the rare earth ion (Tb3+) presents a longer lifetime (1346 mu s) in silica gel doped with Tb(o-CBA)3 than in pure Tb((o-CBA)(3) powder (744 mu s). The reasons responsible for these results are discussed in the context.

关键词： sol-gel method luminescence silica gel rare earth complexes

Heteroaggregation between porphyrin and phthalocyanine bearing oppositely charged substituents

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Chinese journal of Chemistry 1995年第3期13卷 223-230页

作者： MAO, HF TIAN, hj XU, hj CHINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Heteroaggregates composed of cationic porphyrin, meso-tetra(p-trimethylamino)porphyrin iodide, its sine complex and anionic phthalocyanine sodium hydroxygallium 4,4',4 '',4 ''-tetrasulfonated phthalocyanine have been investigated by absorption and fluorescence spectroscopy. It has been found that both free base cationic porphyrin and its zinc complex can form very stable heterodimers with anionic phthalocyanine in water, methanol and dimethylformamide. The stability of the aggregate depends on the polarity as well as the ligation ability of the solvent. No evidence of higher aggregates was detected. Besides axial coordination, steric hindrance which influences the relative orientation of the macrocycles are considered.

关键词： PORPHYRIN PHTHALOCYANINE HETEROAGGREGATION

Solvent effects on competitive intramolecular electron transfer and energy transfer in a covalently linked porphyrin-phthalocyanine heterodimer

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Chinese journal of Chemistry 1996年第5期14卷 412-420页

作者： Tian, hj Zhou, QF Shen, SY Xu, hj ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Photophysical properties of a porphyrin-phthalocyanine heterodimer covalently linked with a dipentoxy chain have been studied. Absorption spectra show that there is weak exciton coupling between the two chromophores in the ground state. Fluorescence spectra show that intramolecular energy transfer from porphyrin to phthalocyanine moiety occurs in competition with electron transfer. The efficiency of these two processes depends upon the mutual orientation of the two chromophores. The effect of solvent, polarity on the intramolecular processes is also discussed.

关键词： solvent effects electron transfer energy transfer porphyrin phthalocyanine

Five New Compounds from Clerodendrum Indicum

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Chinese Chemical Letters 1997年第2期8卷 129-132页

作者： Tian, j Zhao, QS Zhang, hj Lin, ZW Sun, HD ACAD SINICA KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA

From the aerial parts of Clerodendrum indicum, bye new compounds, cleroindicins B-F (1-5) were isolated and their structures identified by spectral method.

关键词： HZ Five New Compounds from Clerodendrum Indicum

Glycine-nitrate auto-combustion synthesis and magnetic properties of nanocrystalline NdAl_(x)Fe_(1-x)O_(3) perovskites

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journal of Rare Earths 2023年第1期41卷 108-115页

作者： E.A.Nforna hj.M.Ngantchou j.N.Ghogomu Department of Fundamental Science Higher Technical Teacher Training CollegeUniversity of BamendaP.O.Box 39BambiliCameroon Department of Chemistry Faculty of SciencesUniversity of DoualaP.O.Box 24157DoualaCameroon Department of Chemistry The University of BamendaP.O.Box 39BambiliCameroon Department of Chemistry University of DschangP.O.Box 67DschangCameroon

The effect of substitution of Fe^(3+) by Al^(3+) on the structure and magnetic properties of NdAl_(x)Fe_(1-x)O_(3) perovskite nano-powders(x=0.0,0.1,0.2,0.3,0.4,and 0.5) prepared by the glycine-nitrate auto-combustion method was *** samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),and energy dispersive X-ray spectroscopy(EDX).The magnetic properties of the samples were investigated using a vibrating sample magnetometer(VSM).The X-ray results for all samples reveal the formation of an orthorhombic perovskite phase(space group Pbnm) with no secondary *** crystallite sizes of the nanoparticles are found to decrease with increasing Al content,and are in the range of 53-38 *** images show spherical nanoparticles with *** FT-IR spectra confirm the presence of metal oxygen *** M-H loop of the pristine NdFeO_(3) sample is antiferromagnetic in the a b plane with weak ferromagnetism in the *** AI inclusions in the pristine polycrystal thereby creating magnetic vacancies is seen to influence the magnetic *** magnetic dilution results in enhanced magnetisation at low Al content;x=0.1,0.2(saturation magnetisation being 2.08 and 2.05 emu/g,respectively) compared to the pristine sample with a saturation magnetisation of 1.43 emu/g due to increased exchange *** dilution with nonmagnetic dopant induces the phase transition from weak ferromagnetic to paramagnetic depending on the impurity *** coercive field for NdFeO_(3) is found to be equal to 1950 Oe and decreases with *** findings lay a ground work for research in tuning magnetic properties and in spintronics with potential applications in data storage,switches and electronic devices.

关键词： Anti-ferromagnetism Weak ferromagnetism Orthorhombic NdAl_(x)Fe_(1-x)O_(3) Perovskite nanopowders Magnetic dilution

Nonlinear Effect of Wave Propagation in Shallow Water

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China Ocean Engineering 1999年第1期14卷 109-114页

作者： Li, Rj Wang, hj Ocean Univ Qingdao Qingdao 266003 Peoples R China

In this paper, a nonlinear model is presented to describe wave transformation in shallow water with the zero- vorticity equation of wave- number vector and energy conservation equation. The nonlinear effect due to an empirical dispersion relation (by Hedges) is compared with that of Dalrymple's dispersion relation. The model is tested against the laboratory measurements for the case of a submerged elliptical shoal on a slope beach, where both refraction and diffraction are significant. The computation results, compared with those obtained through linear dispersion relation, show that the nonlinear effect of wave transformation in shallow water is important. And the empirical dispersion relation is suitable for researching the nonlinearity of wave in shallow water.

关键词： wave propagation shallow water nonlinearity refraction and diffraction empirical dispersion relation

Synthesis of Bis(macrocyclic) Polyamines Containing Rigid Bridging Groups

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Chinese Chemical Letters 1997年第3期8卷 209-212页

作者： Wang, hj Wu, CT WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

This paper deals with the synthesis of three new symmetrical bis (macrocylic) polyamines and their dinuclear copper(I) complexes. All these compounds were identified by elemental analysis and spectral analysis(IR,H-1 ... 详细信息

关键词： HCl Synthesis of Bis macrocyclic Polyamines Containing Rigid Bridging Groups HNMR

Five New Glycosides, Ligurobustosides E, F, I, j and K from Ligustrum Robustum

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Chinese Chemical Letters 1997年第2期8卷 125-128页

作者： Tian, j Zhang, hj Sun, HD Pan, LT Yao, P Chen, DY KUNMING INST BOT LAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA GUIZHO INST TRADIT CHINESE MED GUIYANG 550002PEOPLES R CHINA

Five new monoterpenoid glycosides named ligurobustosides E (1), F (2), I (3), j (4) and K (5) were isolated from the leaves of Ligustrum robustum. Their structures were established by spectroscopic and chemical methods.

关键词： jASONIA-MONTANA