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Chinese Chemical Letters 2017年第8期28卷 1631-1639页

作者： Jing Liu qi-wei chen Kai Wu College of Chemistry and Chemical Engineering Liaoning Normal University BNLMS College of Chemistry and Molecular Engineering Peking University

Bottom-up approach to constructing low-dimensional nanostructures on surfaces with terminal alkynes has drawn great interest because of its potential applications in fabricating advanced functional nanomaterials. The diversity of the achieved products manifests rich chemistry of terminal alkynes and hence careful linking strategies and proper controlling methodologies are required for selective preparations of high-quality target nanoarchitectures. This review summarizes various on-surface linking strategies for terminal alkynes, including non-bonding interactions as well as organometallic and covalent bonds, and presents examples to show effective control of surface assemblies and reactions of terminal alkynes by variations of the precursor structures, substrates and activation modes. Systematic studies of the on-surface linkage of terminal alkynes may help efficient and predictable preparations of surface nanomaterials and further understanding of surface chemistry.

关键词： Terminal alkynes On-surface reactions Surface assemblies Scanning tunneling microscopy Low-dimensional nanostructures

Efficient synthesis of panaxadiol derivatives using continuous-flow microreactor and evaluation of anti-tumor activity

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Chinese Chemical Letters 2015年第3期26卷 334-338页

作者： Yan Wu wei-qi chen Yu-qing Zhao Hu-Ri Piao Key Laboratory of Natural Resources and Functional Molecules of the Changbai Mountain Affiliated Ministry of EducationYanbian University College of Pharmacy Department of Chemistry Fudan University School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University

An efficient method has been developed for the synthesis of a series of（20R）-panaxadiol derivatives（4a–w） using a continuous-flow *** antitumor activities of the newly synthesized compounds were evaluated in vitro in two human prostate adenocarcinoma tumor cell lines（i.e.,PC-3and LNCa P cells）,and their cytotoxicities were evaluated using a standard MTT *** 4c,4h,4p,4q and 4s exhibited higher antitumor activities toward PC-3 cell line than panaxadiol,which was used as a reference standard.

关键词： antitumor adenocarcinoma toward silica batch shorter spectrometer incubated equiv acetate

Cystamine ameliorates liver fibrosis induced by carbon tetrachloride via inhibition of tissue transglutaminase

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World Journal of Gastroenterology 2007年第32期13卷 4328-4332页

作者： Jiang-Feng qiu Zhi-qi Zhang wei chen Zhi-Yong Wu Department of General Surgery Renji Hospital Shanghai Jiaotong University School of Medicine Shanghai 200127 China

AIM： To investigate the anti-fibrosis effect of the tissue transglutarninase （tTG） specific inhibitor cystarnine on liver fibrosis. METHODS： Sixty-eight male Sprague Dawley rats were divided into three groups： normal control, liver fibrosis control and cystamine-treated group. Liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride （CCl4）, and Cystarnine was administrated by intraperitoneal injection starting 2 d before the first administration of CCl4. Animals in each group were further divided into 2 subgroups according to two time points of 4 wk and 8 wk after treatment. Hepatic function, pathological evaluation （semi-quantitative scoring system, SSS） and liver hydroxyproline （Hyp） content were examined. Real-time PCR was used to detect the expression of tTG, smooth muscle alpha actin （α-SMA）, tissue inhibitor of metalloproteinase 1 （TIMP-1） and collagen-1 mRNA. The expressions of tTG and α-SMA protein were detected by Western Blotting. RESULTS： Eight weeks after treatment, the SSS score of liver was significantly less in the cystamine group than that in the fibrosis control group （P 〈 0.01）. The levels of alanine arninotransferase （ALT） and total bile acid （TBA） at the 4 wk and 8 wk time points were decreased in the cystamine group compared with those in fibrosis controls （P 〈 0.01）. Liver hydroxyproline content at the 4 wk and 8 wk time points showed a substantial reduction in the cystamine group compared to fibrosis controls （P 〈 0.01）. The expression of tTG, α-SMA, collagen-1, TIMP-1 mRNA and tTG, as well as α-SMA protein was downregulated in the cystamine group compared to fibrosis controls. CONCLUSION： Cystamine can ameliorate CCl4 induced liver fibrosis and protect hepatic function. The possible mechanism is related to the reduced synthesis of the extracellular matrix （ECM） caused by the inhibition of hepatic stellate cell activation and decreased expression of TIMP-1.

关键词： Tissue transglutaminase Cystamine Liver fibrosis Cross linking Extracellular matrix

Bilateral congenital uveal coloboma concurrent with retinal detachment

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International Journal of Ophthalmology(English edition) 2022年第2期15卷 364-366页

作者： Zi-Jing Huang Jing-Sheng Yi wei-qi chen Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong Shantou 515041Guangdong ProvinceChina

Dear Editor,We are writing to present a bilateral uveal coloboma concurrent with retinal detachment(RD)in a 16-year-old *** are rare,congenital and potentially blinding malformations caused by incomplete closure of em... 详细信息

关键词： incomplete closure concurrent

Surgical treatment for proliferative diabetic retinopathy with ocular albinism

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International Journal of Ophthalmology(English edition) 2023年第3期16卷 479-482页

作者： Zi-Jing Huang Ding-Guo Huang wei-qi chen Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong Shantou 515041Guangdong ProvinceChina

Dear Editor,We are writing to present an uncommon case of a45-year-old woman with bilateral proliferative diabetic retinopathy (PDR) and ocular albinism (OA).Albinism is a group of inherited disorders of tyrosinase ac... 详细信息

关键词： ocular proliferative diabetic

Visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy surgery

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International Journal of Ophthalmology(English edition) 2014年第5期7卷 860-863页

作者： wei-qi chen Vishal Jhanji Hao-Yu chen Gui-Hua Zhang Ping Hou Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Department of Ophthalmology and Visual Sciences the Chinese University of Hong Kong

AIM:To investigate the visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy ***:In this prospective case series, consecutive patients who underwent combined phacoemulsification and pars plana vitrectomy(PPV) under sub-Tenon anesthesia between October 2008 and September 2009 were enrolled. The patients were asked whether they could see the light of the operating microscope or not between various surgical steps with their contralateral eye being ***:A total of 163 eyes of 163 patients were enrolled in this study. After their contralateral eyes were covered, 152(93.3%) patients said that they could not see any light at least during one of the surgical steps. All eyes recovered to at least light perception on the first postoperative day. The incidence of no light perception during the surgery was not related to demographic factors, including age, gender, or type of ocular ***:The incidence of no light perception during combined phacoemulsification and vitrectomy under sub-Tenon anesthesia was high in our *** should be duly informed about this temporary but potential intraoperative event.

关键词： visual impact sub-Tenon anesthesia phacoemulsification vitrectomy

Pinning-down molecules in their self-assemblies with multiple weak hydrogen bonds of C-H···F and C-H···N

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Chinese Chemical Letters 2017年第3期28卷 525-530页

作者： Xin Jin Jacob R. Cramer qi-wei chen Hai-Lin Liang Jian Shang Xiang Shao wei chen Guo-qin Xu Kurt V. Gothelf Kai Wu BNLMS College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Danish-Chinese Centre for Self-Assembly and Function of Molecular Nanostructures on Surfaces at iNANO Department of Chemistry Aarhus University8000 Aorhus C Denmark Department of Chemical Physics School of Chemistry and Materials Science University of Science and Technology of China Hefei 230026 China Department of Chemistry National University of Singapore117543 Singapore SPURc I CREATE Way #15-01CREATE Tower 138602 Singapore

Two-dimensional self-assemblies of four partially fluorinated molecules, 1,4-bis（2,6-difluoropyridin-4-yl）benzene, 4,4＇-bis（2,6-difluoropyridin-4-yl）-1,1＇-biphenyl, 4,4＇-bis（2,6-difluoropyridin-4-yl）-1,1＇：4＇,1＇-terphenyl and 4,4＇-bis（2,6-difluoropyridin-3-yl）-1,1＇-biphenyl, involving weak intermolecular C-H···F and C-H···N hydrogen bonds were systematically investigated on Au（111） with low-temperature scanning tunneling microscopy. The inter-molecular connecting modes and binding sites were closely related to the backbones of the building blocks, i.e., the molecule length determines its binding sites with neighboring molecules in the assemblies while the attaching positions of the N and F atoms dictate its approaching and docking angles. The experimental results demonstrate that multiple weak hydrogen bonds such as C-H···F and C-H···N can be efficiently applied to tune the molecular orientations and the self-assembly structures accordingly.

关键词： Fluorinated pyridyl molecules Grouped hydrogen bonds Molecular self-assembly Molecular design Scanning tunneling microscopy

Partitioning of nitrogen atoms and its effect on retained austenite content in an ultra-low-carbon Cr-Mn-N stainless steel

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Journal of Iron and Steel Research International 2021年第8期28卷 1030-1036页

作者： Zhe Zhu Wan-tang Fu Rong-bin Li qi-wei chen Ze-an Zhou Zhen-hua Wang Jia-qing Liu Shu-hua Sun State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina Shanghai Engineering Research Center of Hot Manufacturing Shanghai Dianji UniversityShanghai 201306China School of Science Yanshan UniversityQinhuangdao 066004HebeiChina

The partitioning of nitrogen atoms and its effect on the retained austenite content(RAC)during quenching and partitioning(Q&P)process were investigated by dilatometry,X-ray diffraction,and field emission transmission electron microscopy with energy-dispersive spectrometer mapping in a 00Cr13Mn8N *** partitioning by diffusion of N atoms from martensite to austenite occurred at 400℃after quenching.N atoms are enriched in austenite after partitioning,and the stability of these N-rich austenite is improved and retained at room temperature during subsequent *** different quenching temperatures(QTs)result in different phase fractions after *** the increase in QT,RAC first increases and then decreases,and the maximum RAC is 28.5 vol.%after quenching at 80℃.A mathematical model was developed to rapidly and accurately characterize the phase fraction in Q&P process based on the relative length change of the samples partitioned after quenching at different QTs.

关键词： Nitrogen partitioning Quenching and partitioning Retained austenite Energy-dispersive spectrometer mapping Dilatometry Ultra-low-carbon stainless steel

Newly Designed Cr-Mn Alloyed Ultra-high Strength Steel without Boron Addition for Hot-stamping Processing

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Journal of Iron and Steel Research International 2015年第12期22卷 1144-1148页

作者： Guo-hui ZHU Hong-bing ZHOU qin-yi LI qi-wei chen Hai-rong GU Yong-gang LIU Anhui University of Technology Ma'anshan Iron & Steel Company Limited

A newly designed hot-stamping steel alloyed by chromium （Cr） and manganese （Mn） without boron （B） addition was developed for automobile mass reduction. The experimental results showed the Cr-Mn alloyed steel could be quenched to full martensite microstructure when the cooling rate was higher than 14 ℃/s. Yield strength, tensile strength and elongation of the experimental hot stamping part reached 1 180 MPa, 1 645 MPa and 8.4% , respectively. The experimental hot stamping part possessed higher tensile strength and elongation, compared with conventional hot-stamping steel of 22MnB5. Furthermore, excellent processing flexibility would be obtained in this novel hot-stamping steel because of its lower critical cooling rate and phase transformation temperature. The design of the composition and investigations of microstructure, mechanical properties and hot-stamping processing were also studied.

关键词： hot-stamping ultra-high strength steel finite element method mechanical property

Protective effects of upregulated HO-1 gene against the apoptosis of human retinal pigment epithelial cells in vitro

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International Journal of Ophthalmology(English edition) 2021年第5期14卷 649-655页

作者： Yu Hong Yu-Ping Liang wei-qi chen Liu-Xia You qing-Feng Ni Xiu-Yun Gao Xiao-Rong Lin Department of Ophthalmology the Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Department of Clinical Laboratory the Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina

AIM:To investigate the protective effect of heme oxygenase-1(HO-1)against H_(2)O_(2)-induced apoptosis in human ARPE-19 ***:The lentiviral vector expressing HO-1 was prepared and transfected into apoptotic ARPE-19 cells induced by H_(2)O_(2).Functional experiments including cell counting kit-8(CCK-8)assay,flow cytometry(FCM)and mitochondrial membrane potential assay were ***:The ultrastructure of ARPE-19 cells was observed using transmission electron microscope(TEM).It was found that exogenous HO-1 significantly ameliorated H_(2)O_(2)-induced loss of cell viability,apoptosis and intracellular levels of reactive oxygen species(ROS)in ARPE-19 *** overexpression of HO-1 facilitated the transfer of nuclear factor erythroid-2-related factor 2(Nrf2)from cytoplasm to nucleus,which in turn upregualted expressions HO-1 and B-cell lymphoma-2(Bcl-2).Furthermore,HO-1 upregulation further inhibited H_(2)O_(2)-induced release of cysteinyl aspartate specific proteinase-3(caspase-3).CONCLUSION:Exogenous HO-1 protect ARPE-19 cells against H_(2)O_(2)-induced oxidative stress by regulating the expressions of Nrf2,HO-1,Bcl-2,and caspase-3.

关键词： retinitis pigmentosa heme oxygenase-1 ARPE-19 cell mechanism