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MicroRNA-451 from Human Umbilical Cord-Derived Mesenchymal Stem Cell Exosomes Inhibits Alveolar Macrophage Autophagy via Tuberous Sclerosis Complex 1/Mammalian Target of Rapamycin Pathway to Attenuate Burn-Induced Acute Lung Injury in Rats
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作者 Zhigang Jia Lin Li +5 位作者 Peng Zhao Guo Fei Shuangru Li Qinqin Song Guangpeng Liu Jisong Liu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第9期1030-1043,共14页
Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechan... Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechanisms by which miR-451 in hUC-MSC-Exos reduces ALI by modulating macrophage autophagy.Methods Exosomes were isolated from hUC-MSCs.Severe burn-induced ALI rat models were treated with hUC-MSC-Exos carrying the miR-451 inhibitor.Hematoxylin-eosin staining evaluated inflammatory injury.Enzyme-linked immunosorbnent assay measured lipopolysaccharide(LPS),tumor necrosis factor-α,and interleukin-1βlevels.qRT-PCR detected miR-451 and tuberous sclerosis complex 1(TSC1)expressions.The regulatory role of miR-451 on TSC1 was determined using a dual-luciferase reporter system.Western blotting determined TSC1 and proteins related to the mammalian target of rapamycin(mTOR)pathway and autophagy.Immunofluorescence analysis was conducted to examine exosomes phagocytosis in alveolar macrophages and autophagy level.Results hUC-MSC-Exos with miR-451 inhibitor reduced burn-induced ALI and promoted macrophage autophagy.MiR-451 could be transferred from hUC-MSCs to alveolar macrophages via exosomes and directly targeted TSC1.Inhibiting miR-451 in hUC-MSC-Exos elevated TSC1 expression and inactivated the mTOR pathway in alveolar macrophages.Silencing TSC1 activated mTOR signaling and inhibited autophagy,while TSC1 knockdown reversed the autophagy from the miR-451 inhibitor-induced.Conclusion miR-451 from hUC-MSC exosomes improves ALI by suppressing alveolar macrophage autophagy through modulation of the TSC1/mTOR pathway,providing a potential therapeutic strategy for ALI. 展开更多
关键词 Acute lung injury Human umbilical cord mesenchymal stem cell-derived exosomes MicroRNA-451 Tuberous sclerosis complex 1 Mammalian target of rapamycin pathway AUTOPHAGY
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一种移动感知的太赫兹无线局域网定向MAC协议
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作者 任智 陈春宇 +1 位作者 古金东 姚毅 《电讯技术》 北大核心 2024年第5期725-731,共7页
现有太赫兹无线局域网定向MAC(Medium Access Control)协议中,节点移动情况下PNC(PicoNet)发送beacon帧时存在部分控制字段浪费、CTAP(Channel Time Allocation Period)中PNC与DEV(Device)进行波束赋形开销偏大等问题。为此,提出了一种... 现有太赫兹无线局域网定向MAC(Medium Access Control)协议中,节点移动情况下PNC(PicoNet)发送beacon帧时存在部分控制字段浪费、CTAP(Channel Time Allocation Period)中PNC与DEV(Device)进行波束赋形开销偏大等问题。为此,提出了一种移动感知的太赫兹无线局域网定向MAC(Mobility-aware Directional MAC,MA-MAC)协议。该协议采用基于卡尔曼算法的节点扇区预测机制对移动节点的扇区范围进行迭代预测,采用基于DEV扇区预测的beacon帧内容填充机制对beacon帧中时隙分配字段进行填充,采用基于节点扇区预测的快速波束赋形机制使得PNC与DEV之间波束赋形操作简化。通过仿真验证,与基于IEEE 802.15.3c的太赫兹无线局域网定向MAC协议和现有协议进行对比,MA-MAC协议下网络吞吐量得到了提升,网络平均时延、网络整体控制开销得到了改善。 展开更多
关键词 太赫兹无线局域网 定向通信 mac协议 移动感知
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高效低时延分级多PAN太赫兹无线网络MAC层优化协议
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作者 刘洋 任智 +1 位作者 古金东 周逊 《小型微型计算机系统》 CSCD 北大核心 2024年第8期1966-1971,共6页
针对现有分级多PAN太赫兹无线网络MAC(Medium Access Control)协议中存在的子网形成方案不合理以及私有CTA(Channel Time Allocation)与子网内实际负载不匹配等问题,提出了一种高效低时延的MAC层优化协议.该协议采用基于泛听的按需形成... 针对现有分级多PAN太赫兹无线网络MAC(Medium Access Control)协议中存在的子网形成方案不合理以及私有CTA(Channel Time Allocation)与子网内实际负载不匹配等问题,提出了一种高效低时延的MAC层优化协议.该协议采用基于泛听的按需形成子网机制避免了子网分布不均匀以及因子网形成后没有节点加入而造成的私有CTA资源浪费的问题.在子网形成后,子微微网协调器(Piconet Coordinator,PNC)根据子网内实际负载情况自适应选择私有CTA时隙资源优化机制,让有数据传输需求的节点及时将数据发出.仿真结果表明,所提出的方案能有效地降低数据帧平均接入时延,提高吞吐量以及数据帧的传输成功率. 展开更多
关键词 太赫兹 分级 多PAN 无线网络 媒体访问控制协议 低时延
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Effect of poly(ethylene glycol) modified polyethylenimine polyelectrolyte complex on pharmaceutical characteristics and uptake on breast cancer cell 被引量:1
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作者 刘立婷 齐宪荣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第4期291-296,共6页
Cationic polyethylenimine (PEI) with dextran fluorescein anionic (DFA) or oligodeoxynucleotide (ODN) could form polyelectrolyte complex by self-assembly as a gene delivery vector. This study was designed to inve... Cationic polyethylenimine (PEI) with dextran fluorescein anionic (DFA) or oligodeoxynucleotide (ODN) could form polyelectrolyte complex by self-assembly as a gene delivery vector. This study was designed to investigate the effects on pharmaceutical characteristics and cell uptake PEI after a long-circulation modification with poly(ethylene glycol) (PEG). DFA or ODN reacted with PEI or PEI-PEG to form polyelectrolyte complexes. Surface characters of these complexes and the retardation of ODN by PEI and PEI-PEG were evaluated. The uptake rates of DFA/PEI and DFA/PEI-PEG complexes by MCF-7 cells were evaluated by flow cytometry. Confocal laser scanning microscopy was utilized to visualize the internalization of these complexes. ODN/PEI complex showed the dependence of their size and ξ potential on the N/P ratio. ODN/PEI-PEG complex were much less affected by N/P ratio and their size was around 30 100 nm. PEI and PEI-PEG retarded ODN even at N/P ratio as low as 4, and complete retardation was found at N/P ratio of 8. The uptake rate by MCF-7 cells was direct correlated to the DFA concentration and incubation time, and the uptake rate could exceed 99% under the selected condition. The results in this study showed that PEI self-assembly polyelectrolyte complex after stealth or long circulation modification may increase the ability as a gene vector to delivery genes into cells. 展开更多
关键词 Polyelectrolyte complex POLYETHYLENIMINE Uptake rate SELF-ASSEMBLY Breast cancer cell
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Macular Perfusion Changes and Ganglion Cell Complex Loss in Patients with Silicone Oil-related Visual Loss 被引量:10
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作者 MA Ya ZHU Xiao Qing PENG Xiao Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第3期151-157,共7页
Objective The aim of this study was to investigate macular perfusion changes and ganglion cell complex(GCC)loss in patients with unexplained visual loss following vitrectomy and silicone oil(SO)tamponade,and to evalua... Objective The aim of this study was to investigate macular perfusion changes and ganglion cell complex(GCC)loss in patients with unexplained visual loss following vitrectomy and silicone oil(SO)tamponade,and to evaluate the correlation between retinal blood flow and GCC loss using optical coherence tomography angiography(OCTA)and optical coherence tomography(OCT).Methods This retrospective study included seven eyes(seven patients)with unexpected visual loss after vitrectomy and SO tamponade.OCTA was used to evaluate the alterations in retinal vessel density(VD)in the superficial capillary plexus(SCP),deep capillary plexus(DCP),and radial peripapillary capillary plexus(RPCP).OCT was used to measure the thickness of GCC and retinal nerve fiber layer(RNFL).Medical records of patients were reviewed.Results Quantitative analysis of OCTA images revealed a significant reduction in SCP VD in the affected eyes compared with the controls(all sections P<0.05).No difference was found in GCC thickness,but FLV(focal loss volume)and GLV(global loss volume)were significantly higher in the affected eyes(both P<0.001).SCP VD was inversely correlated with FLV and GLV.Conclusions Silicone oil-related severe visual loss was associated with superficial retinal microvasculature damage and ganglion cell apoptosis. 展开更多
关键词 SILICONE oil Visual LOSS Optical coherence tomography ANGIOGRAPHY GANGLION cell complex
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Heterometallic Trinuclear Ni_2Zn and Ni_2Mn Complexes of Macrocyclic Oxamide: Synthesis and Crystal Structures 被引量:3
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作者 孙亚秋 刘尚远 王菁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期39-44,共6页
Two novel heterometallic trinuclear complexes of macrocyclic oxamide [Mn(NiL)2(HBTC)H2O] (1) and [Zn(NiL)2(HBTC)H2O] (2) (NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien,... Two novel heterometallic trinuclear complexes of macrocyclic oxamide [Mn(NiL)2(HBTC)H2O] (1) and [Zn(NiL)2(HBTC)H2O] (2) (NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H3BTC = 1,3,5-benzenetricarboxylic acid) have been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. For 1, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.3595(5), b = 23.1498(11), c = 17.2558(8) and =101.2530(10)°. For 2, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.5214(8), b = 20.6566(14), c = 18.4126(13) and = 92.6770(10)°. The structures of 1 and 2 have oxamido-bridged trinuclear [NiⅡ2MⅡ] units and consist of two-dimensional supramolecular architectures formed by strong O–H…O intermolecular hydrogen bonds. 展开更多
关键词 macrocyclic oxamide complex solvothermal synthesis heterometallic complex
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Complex formulations, simple techniques: Can 3D printing technology be the Midas touch in pharmaceutical industry? 被引量:6
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作者 Shrawani Lamichhane Santosh Bashyal +6 位作者 Taekwang Keum Gyubin Noh Jo Eun Seo Rakesh Bastola Jaewoong Choi Dong Hwan Sohn Sangkil Lee 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第5期465-479,共15页
3 D printing is a method of rapid prototyping and manufacturing in which materials are deposited onto one another in layers to produce a three-dimensional object. Although 3 D printing was developed in the 1980 s and ... 3 D printing is a method of rapid prototyping and manufacturing in which materials are deposited onto one another in layers to produce a three-dimensional object. Although 3 D printing was developed in the 1980 s and the technology has found widespread industrial applications for production from automotive parts to machine tools,its application in pharmaceutical area is still limited. However,the potential of 3 D printing in the pharmaceutical industry is now being recognized. The ability of 3 D printing to produce medications to exact specifications tailored to the needs of individual patients has indicated the possibility of developing personalized medicines. The technology allows dosage forms to be precisely printed in various shapes,sizes and textures that are difficult to produce using traditional techniques. However,there are various challenges associated with the proper application of3 D printing in the pharmaceutical sector which should be overcome to exploit the scope of this technology. In this review,an overview is provided on the various 3 D printing technologies used in fabrication of complex dosage forms along with their feasibility and limitations. 展开更多
关键词 Three-dimensional PRINTING PERSONALIZED medicine FUSED deposition modeling INKJET PRINTING complex formulations
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Semi-solid moulding:Competition to cast and machine from forging in making automotive complex components 被引量:7
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作者 S.P.MIDSON 《中国有色金属学会会刊:英文版》 CSCD 2010年第S3期1042-1047,共6页
The very latest technique for impeller manufacture is called semi-solid moulding(SSM).Cummins Turbo Technologies Limited,together with Aluminum Complex Components Inc,developed SSM compressor wheels as a way of achiev... The very latest technique for impeller manufacture is called semi-solid moulding(SSM).Cummins Turbo Technologies Limited,together with Aluminum Complex Components Inc,developed SSM compressor wheels as a way of achieving cost and durability performance somewhere between that of cast and machined from solid(MFS) aluminium alloy wheels.Experimental results show SSM material has a superior microstructure and mechanical properties over cast and comparable to MFS materials.Component testing including durability testing,using accelerated speed cycle tests,proves SSM compressor wheels emerge as being significantly more durable than cast equivalents and approaching that of MFS impellers.Further challenges for semi-solid processing in manufacture of other complex components and other materials in automotive industry in terms of both cost and durability are also discussed. 展开更多
关键词 aluminum alloys SEMI-SOLID MOULDING durability automotive complex component TURBOCHARGER COMPRESSOR wheel
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An analytical method for Fe(Ⅱ) and Fe(Ⅲ) determination in pharmaceutical grade iron sucrose complex and sodium ferric gluconate complex 被引量:5
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作者 Daniele Merli Antonella Profumo Carlo Dossi 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第6期450-453,共4页
A robust voltammetric method has been developed and validated for the determination of Fe(Ⅱ) and Fe(Ⅲ) in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concen... A robust voltammetric method has been developed and validated for the determination of Fe(Ⅱ) and Fe(Ⅲ) in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe(Ⅱ) and Fe(Ⅲ) composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex. 展开更多
关键词 Sodium ferric gluconatecomplex Iron sucrose complex Iron polysaccharides VOLTAMMETRY
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Quantitative analysis of cefixime via complexation with palladium(Ⅱ) in pharmaceutical formulations by spectrophotometry 被引量:3
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作者 Syed Najmul Hejaz Azmi Bashir Iqbal +3 位作者 Nada Said Hassan Al-Humaimi Iman Rashid Saif Al-Salmani Noora Ali Saad Al-Ghafri Nafisur Rahman 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第4期248-256,共9页
An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladi... An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution (pH 3) in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer's law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell's sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods. 展开更多
关键词 SPECTROPHOTOMETRY CEFIXIME Palladium ion Pd(II)-cefixime complex
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Catalytic hydrolysis of phosphate diester (BNPP) and plasmid DNA by mononuclear macrocyclic polyamine metal complexes 被引量:3
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作者 Qing Xiang Xiang Li Qun Zhang +1 位作者 Xiao Qi Yu Ru Gang Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期523-526,共4页
The activities of the catalytic hydrolysis of phosphate diester (BNPP) [bis(p-nitrophenyl)phosphate diester] and plasmid DNA (pUC 18) by mononuclear macrocyclic polyamine metal complexes have been investigated i... The activities of the catalytic hydrolysis of phosphate diester (BNPP) [bis(p-nitrophenyl)phosphate diester] and plasmid DNA (pUC 18) by mononuclear macrocyclic polyamine metal complexes have been investigated in this paper. The results showed that the highest activity in hydrolysis of BNPP was obtained with le--Zn(II) complex (composed of lipophilic group) as catalyst. The hydrolysis rate enhancement is up to 3.64 × 10^4 fold. These metal complexes could effectively promote the cleavage of plasmid DNA (pUC18) at physiological conditions. 展开更多
关键词 Catalytic hydrolysis macrocyclic polyamine Zn(II) complex BNPP Plasmid DNA
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Synthesis and Structure of a Novel Macrocyclic Complex [Cd_2(phen)_4(phth)_2]·4H_2O 被引量:2
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作者 SUN Ya-Guang GAO En-Jun +1 位作者 WEI De-Zhou LIU Yi-Nan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1298-1301,共4页
A novel complex [Cd2(phen)4(phth)2]·4H2O has been synthesized by the reaction of Hzphth(phthalic acid) and phen(1,10-phenanthroline) with Cd(Ⅱ) in ethanol-water solution. X-ray crystal structure analys... A novel complex [Cd2(phen)4(phth)2]·4H2O has been synthesized by the reaction of Hzphth(phthalic acid) and phen(1,10-phenanthroline) with Cd(Ⅱ) in ethanol-water solution. X-ray crystal structure analysis shows it crystallizes in triclinic, space group PI- with a = 10.619(3), b = 12.560(4), c = 12.651(4) A, a = 98.775(5), β = 109.035(5),γ = 113-576(5)°, C32H24CdN4O6, Mr= 672.95, V = 1381.7(7)A^3, Rint = 0.0358, Z = 2, Dc= 1.618 g/cm^3,μ = 0.845 mm^-1, -6 ≤h≤13, -15 ≤k ≤13, -15 ≤l≤14, F(000) = 680, S = 1.038, R = 0.0480 and wR = 0.0849 for 3992 observed reflections (1 〉 2σ(Ⅰ)). Phth bridges Cd(Ⅱ) to form a macrocyclic compound, and a 2D supramolecular motif is formed through hydrogen bonds and π-π interaction. 展开更多
关键词 cadmium complex crystal structure hydrogen bonding π-π interaction
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Synthesis and Characterization of Two Binuclear Macrocyclic Zinc(Ⅱ) Complexes by Anion Exchange 被引量:2
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作者 欧光川 黄中文 +2 位作者 潘泽毅 周东来 袁先友 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期903-908,共6页
Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [Z... Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(Ⅱ) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2. 展开更多
关键词 macrocyclic zinc(Ⅱ) complexes BINUCLEAR VANADIUM anion exchange
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A One-dimensional Transition Metal Complex Constructed from 24-Membered Hinge-shaped Macrocycles with Salicylic Acid and 1,3-Bis(4-pyridyl)propane 被引量:2
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作者 陈友存 汪快兵 王彦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1613-1618,共6页
A new 1-D coordination polymer [Cd(Hsal)2(bpp)2] 1 was hydrothermally synthesi- zed by self-assembly of the corresponding metal oxide and salicylic acid (H2sal) with exo-bidentate flexible dipyridyl ligand 1,3-... A new 1-D coordination polymer [Cd(Hsal)2(bpp)2] 1 was hydrothermally synthesi- zed by self-assembly of the corresponding metal oxide and salicylic acid (H2sal) with exo-bidentate flexible dipyridyl ligand 1,3-bis(4-pyridyl)propane (bpp). X-ray crystal structure analysis reveals that complex 1 crystallizes in monoclinic,space group C2/c with a = 18.942(3),b = 12.9309(19),c = 16.504(2) A,β = 120.072(2)°,V = 3498.3(9)A^3,Z = 4,C40H38CdN4O6,Mr = 783.14,Dc = 1.487 g/cm^3,μ = 0.679 mm^-1,F(000) = 1608,R = 0.0619 and wR = 0.1435 for 3153 observed reflections (I 〉 2σ(I)). The most remarkable feature of 1 lies in the 1-D chain by repeating [Cd2(bpp)2] units which consist of a 24-membered macrocyclic ring. The 1-D motifs are further connected by C–H… O hydrogen bonds to generate a 2-D structure. In addition,thermal stability and luminescent property of compound 1 were also documented. 展开更多
关键词 self-assembly cadmium(II) complex 1-D coordination polymer luminescent property
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Chiral Resolution of β-dl-Phenylalanine Using Chiral Macrocyclic Nickel(Ⅱ) Complexes 被引量:2
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作者 欧光川 李治章 +1 位作者 张敏 袁先友 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期707-712,共6页
The reactions of chiral four-coordinated nickel(Ⅱ) complex [Ni(RR-L)](ClO4)2/[Ni(SS- L)](ClO4)2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni(RR-L)(β-d-HPhe)]... The reactions of chiral four-coordinated nickel(Ⅱ) complex [Ni(RR-L)](ClO4)2/[Ni(SS- L)](ClO4)2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni(RR-L)(β-d-HPhe)](ClO4)2(1) and [Ni(SS-L)(β-l-HPhe)](ClO4)2(2), respectively(L = 5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, HPhe = phenylalanine). Single-crystal X-ray diffraction analyses revealed that the nickel(Ⅱ) atom displays a distorted octahedral coordination geometry by coordinating with four nitrogen atoms of L in a folded configuration, and two carboxylate oxygen atoms of β-d/l-HPhe in cis-position in both complexes. The monomers of [Ni(RR-L)(β-d-HPhe)]2+ and [Ni(SS-L)(β-l-HPhe)]2+ are connected through intermolecular hydrogen bonds to generate one-dimensional zigzag chains, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy. 展开更多
关键词 chiral resolution macrocyclic nickel(Ⅱ) complexes β-dl-phenylalanine
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Synthesis and Crystal Structure of a New Dinuclear Manganese(Ⅱ) Manganese(Ⅲ) Complex of a Macrocyclic Ligand 被引量:1
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作者 JIANFang-fang XIAOHai-lian XULiang-zhong PANGLei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期725-728,共4页
A mixed-valence dinuclear manganese complex, [Mn ⅡMn ⅢL](ClO 4)·1/2MeOH, where L is a macrocyclic ligand derived from the cyclocondensation of sodium 2,6-diformyl-4-methylphenolate with N,N-bis(2-aminoethyl)... A mixed-valence dinuclear manganese complex, [Mn ⅡMn ⅢL](ClO 4)·1/2MeOH, where L is a macrocyclic ligand derived from the cyclocondensation of sodium 2,6-diformyl-4-methylphenolate with N,N-bis(2-aminoethyl)-2-hydroxybenzyl amine, was obtained and its structure was determined by X-ray diffraction. The orange crystal is a monoclinic system with space group P2 1/c and lattice parameters a=1.1617(4), b=1.4005(3), c=1.4641(3) nm, β=113.03(2)°, and Z=2. The crystal structure shows that each pendant-arm is bonded in a bidentate fashion to the adjacent metal atom and that both the arms are on the same side of the macrocycle. The two Mn atoms are bridged by two μ 2-phenoxy oxygen atoms of the tetra-imine macrocycle, and each Mn atom, locating in a trigonal prismatic coordination environment(N 3O 3), is six-coordinated by the two imine nitrogen atoms, one tertiary nitrogen atom and a pendant phenol moiety apart from the two oxygen atoms. 展开更多
关键词 Dinuclear manganese complex macrocyclic compound Crystal structure
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Syntheses and Structures of Three Hybrid Materials Using Vanadium Polyoxoanions and Macrocyclic Copper Complex as Building Blocks 被引量:4
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作者 欧光川 廖阳 +2 位作者 向岳峰 袁先友 李治章 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期135-142,共8页
The reactions of the four-coordinated macrocyclic copper complex [CuL](ClO4)2(L = 1,4,8,11-tetraazacyclotetradecane) with NH4VO3 under different conditions gave three inorganic-organic hybrid materials of [CuL][VO... The reactions of the four-coordinated macrocyclic copper complex [CuL](ClO4)2(L = 1,4,8,11-tetraazacyclotetradecane) with NH4VO3 under different conditions gave three inorganic-organic hybrid materials of [CuL][VO3]2·2.33H2O(1), [CuL]3[V(10)O(28)]·8H2O(2) and [Cu L]3[V6O(18)]·8H2O(3). Single-crystal X-ray diffraction analyses reveal that three diverse vanadium polyoxoanions, [V6O(18)]6- ring, [V(10)O(28)]6- cluster, and [V(12)O(35)]^10- ring, were isolated from the same reactant NH4VO3 under different conditions. The [CuL]^2+ bridges the [V10O28]6- clusters to form a two-dimensional sheet in 2, and link the [V6O(18)]^6- rings in 1 and [V(12)O(35)]^10- rings in 3 into three-dimensional frameworks, respectively. 展开更多
关键词 polyoxovanadate macrocyclic copper(Ⅱ) complexes hybrid materials
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Neurochemical mechanism of the gastrointestinal interdigestive migrating motor complex in rats with acute inflammatory stomach ache 被引量:1
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作者 Xiaoli Xu Qin Li +1 位作者 Lv Zhou Liqiang Ru 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第27期2136-2143,共8页
The normal gastrointestinal interdigestive migrating motor complex cycle was interrupted, and paroxysmal contraction appeared after formaldehyde-induced stomach ache. Activities of nitric oxide synthase, acetylcholine... The normal gastrointestinal interdigestive migrating motor complex cycle was interrupted, and paroxysmal contraction appeared after formaldehyde-induced stomach ache. Activities of nitric oxide synthase, acetylcholinesterase and vasoactive intestinal peptide neurons were significantly reduced, whereas activities of calcitonin gene-related peptide neurons were significantly increased in the pyloric sphincter muscular layer, myenteric nerve plexus and submucous nerve plexus. Electroacupuncture at Zusanfi (ST36) suppressed paroxysmal contraction in rats with formaldehyde-induced stomach ache, and neurons in the enteric nervous system were normal. These results indicated that nitrergic neurons, cholinergic neurons, vasoactive intestinal peptide neurons and calcitonin gene-related peptide neurons in the enteric nervous system may be involved in changes to the gastrointestinal interdigestive migrating motor complex following stomach ache, and that electroacupuncture can regulate this process. 展开更多
关键词 pyloric sphincter inflammatory pain interdigestive migrating motor complex enteric nervoussystem ELECTROACUPUNCTURE neural regeneration
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Synthesis and Structure of a New Bicadmium (Ⅱ) Complex with Macrocyclic Hexaaza Bearing Hydroxyethyl Pendants 被引量:1
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作者 高健 陈军 +3 位作者 许兴友 杨绪杰 陆路德 汪信 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1287-1291,共5页
A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space gro... A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space group P1 with a = 15.630(3), b = 15.990(3), c = 16.330(3) ?, α = 89.90(3), β = 68.87(3), γ = 87.94(3)o, V = 3804.1(13) ?3, Mr = 1034.22, Z = 4, F(000) = 2060, Dc = 1.806 g/cm3, T = 293(2) K, μ = 1.468 mm-1 and λ = 0.71073 ?. The structure was refined to R = 0.0779 and wR = 0.1960 for 7034 observed reflections with I > 2σ(I). 展开更多
关键词 crystal structure cadmium (Ⅱ) complex macrocyclic structure hydroxyethyl pendants ES-MS
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EEG epileptic seizure detection and classification based on dual-tree complex wavelet transform and machine learning algorithms 被引量:4
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作者 Itaf Ben Slimen Larbi Boubchir +1 位作者 Zouhair Mbarki Hassene Seddik 《The Journal of Biomedical Research》 CAS CSCD 2020年第3期151-161,共11页
The visual analysis of common neurological disorders such as epileptic seizures in electroencephalography(EEG) is an oversensitive operation and prone to errors,which has motivated the researchers to develop effective... The visual analysis of common neurological disorders such as epileptic seizures in electroencephalography(EEG) is an oversensitive operation and prone to errors,which has motivated the researchers to develop effective automated seizure detection methods.This paper proposes a robust automatic seizure detection method that can establish a veritable diagnosis of these diseases.The proposed method consists of three steps:(i) remove artifact from EEG data using Savitzky-Golay filter and multi-scale principal component analysis(MSPCA),(ii) extract features from EEG signals using signal decomposition representations based on empirical mode decomposition(EMD),discrete wavelet transform(DWT),and dual-tree complex wavelet transform(DTCWT) allowing to overcome the non-linearity and non-stationary of EEG signals,and(iii) allocate the feature vector to the relevant class(i.e.,seizure class "ictal" or free seizure class "interictal") using machine learning techniques such as support vector machine(SVM),k-nearest neighbor(k-NN),and linear discriminant analysis(LDA).The experimental results were based on two EEG datasets generated from the CHB-MIT database with and without overlapping process.The results obtained have shown the effectiveness of the proposed method that allows achieving a higher classification accuracy rate up to 100% and also outperforms similar state-of-the-art methods. 展开更多
关键词 ELECTROENCEPHALOGRAPHY epileptic seizure detection feature extraction dual-tree complex wavelet transform machine learning
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