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Induction of Apoptosis by L-NMMA,via FKHRL1/ROCK Pathway in Human Gastric Cancer Cells

Biomedical and Environmental Sciences 2006年第4期19卷 285-291页

作者： YONG-ZHONG wang ZHEN-qing feng Department of Pathology Nanjing Medical University Nanjing 210029 Jiangsu China

Objective To investigate the apoptosis-inducing effect of endogenous nitric oxide （NO） suppression in gastric cancer cells and its mechanisms. Methods Apoptosis of gastric cancer cells was detected by flow cytometry. Expression of phosphorylated FKHRL1 （thr-32, ser-253） and FKHRL1 in gastric cancer cells was analyzed using Western blotting. Immunofluorescence assay was performed to localize the intracellular phosphorylated FKHRL1 （thr-32, ser-253） and FKHRL 1. Transfection of FKHRL1-HA wild type and mutant FKHRL1-HA T32A constructs was performed by lipofectamine plus reagent. NO generation was determined by Griess reaction. Results Gastric cancer cells were significantly apoptotic after treatment with NG-monomethyl-L-arginine （L-NMMA, a nitric oxide synthase inhibitor）, compared with the control （P〈0.01）. The apoptosis of gastric cancer cells induced by L-NMMA was dose-dependent and time-independent. However, the Z-DEVD-fmk, a caspase-3, 6, 7, 8, l0 inhibitor, did not prevent the apoptosis. The immunofluorescence assays showed that FKHRL1 protein was strongly expressed in the nucleu and p-FKHRL1 thr-32 protein was ：strongly expressed in the cytoplasm of SGC-7901 cells when endogenous nitric oxide generation was blocked by L-NMMA, but no change in FKHRL1 ser-253 phosphorylation. Nevertheless, ROCK protein was strongly expressed in p-FKHRL1 thr-32-positive SGC-7901 cells. The wortmannin, an inhibitor of phosphoinositol-3-OH kinase （PI3K）, did not block the phosphorylated FKHRL1 thr-32 protein induced by L-NMMA. However, Y-27632, a specific inhibitor of the protein kinase ROCK, significantly blocked apoptosis induced by phosphorylated FKHRL1 thr-32 （P〈0.01）, which was mediated by L-NMMA. A significant decrease in NO generation （P〈0.01） and a significant increase in apoptosis （P〈0.01） were observed when FKHRL1-HA wild-type cells were transfected, which caused increased FKHRL1 thr-32 phosphorylation. Conclusions L-NMMA triggers gastric carcinoma cell apoptosis, possibly

关键词： Gastric carcinoma Nitric oxide FKHRL1 Apoptosis Signaling

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Are the altitudinal patterns of plant diversity derived from field surveys consistent with those from empirical integrated methods?

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Journal of Mountain Science 2023年第5期20卷 1307-1315页

作者： ZHAN qing-hua FU Zhi-hao ZHOU Ya-dong YAN Xue wang qing-feng School of Life Sciences Nanchang UniversityNanchang 330031China Wuhan Botanical Garden/Core Botanical Gardens Chinese Academy of SciencesWuhan 430074China Sino-Africa Joint Research Center(SAJOREC) Chinese Academy of SciencesWuhan 430074China

Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of ***,few studies have compared the differences between the two methods on the same ***,we addressed and compared the altitudinal patterns of species richness(SR),phylogenetic diversity(PD),the standardized effect size of phylogenetic diversity(PDses)and mean phylogenetic distance(MPDses)of about 580 angiosperms growing on Mount Kenya from two independent datasets:one is based on our several times field surveys in this mountain and another one is based on empirical data integrated from *** found that the altitudinal diversity patterns of field surveys dataset were consistent with the empirical integrated *** SR and PD showed hump-shaped patterns along the altitude,and both PDses and MPDses showed monotonically decreasing patterns along the *** ratio of diversity between field surveys dataset and empirical integrated dataset were gradually increase along the *** research provides new insight for understanding the altitudinal diversity patterns of plants of a tropical mountain.

关键词： Mount Kenya Africa Surveys Interpolation method Taxonomic Phylogenetic

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Effect of Tempering Temperature on Microstructure and Mechanical Properties of Steel Containing Ni of 9%

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Journal of Iron and Steel Research International 2011年第9期18卷 47-51,58页

作者： ZHAO Xi-qing PAN Tao wang qing-feng SU Hang YANG Cai-fu YANG qing-xiang State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Division of Structural Material Research Central Iron and Steel Research InstituteBeijing 100081China

Mechanical properties of quenching,intercritical quenching and tempering （QLT） treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures of steel containing Ni of 9% at different tempering temperatures were observed by optical microscope （OM） and transmission electron microscope （TEM）. The volume fraction of austenite was estimated by XRD. The results show that high strength and cryogenic toughness of steel containing Ni of 9% are obtained when the tempering temperature are between 540 and 580 ℃. The microstructure keeps the dual phase lamellar structure after the intercritical quenching and there is cementite created in the Ni-rich constituents when tempering temperature is 540 ℃. When tempering temperatures are between 560 and 580 ℃,the reversed austenites （γ′） grow up and the dual phase lamellar structure is not clear. The γ′ becomes instable at 600 ℃. When tempered at temperature ranging from 500 to 520 ℃,the increase of dislocation density in the lamellar matrix makes both tensile strength and yield strength decrease. When tempered at 540 ℃ and higher temperature,the yield strength decreases continuously because the C and alloying elements in the matrix are absorbed by the cementite and the γ′,so the yield ratio is decreased by the γ′. There are two toughness mechanisms at different tempering temperatures. One is that the precipitation of cementite absorbs the carbon in the steel which plays a major role in improving cryogenic toughness at lower temperature. Another is that the γ′ and the purified matrix become major role at higher tempering temperature. When the tempering temperature is 600 ℃,the stability of γ′ is decreased quickly,even the transformation takes place at room temperature,which results in a sharp decrease of Charpy-V impact energy at 77 K. The tempering temperature range is enlarged by the special distribution of cementite and the lamellar structure.

关键词： steel containing Ni of 9% tempering temperature cementite reversed austenite cryogenic toughness

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Effect of Niobium on Dynamic Recrystallization Behavior of 5%Ni Steel

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Journal of Iron and Steel Research International 2013年第6期20卷 38-44页

作者： LEI Xiao-rong DING qing-feng CHEN Yuan-yuan RUI Xiao-long LI Shu-rui wang qing-feng State Key Laboratory of Metastable Materials Science and Technology Yanshan University Research and Development Center Wuhan Iron and Steel Company

The single-pass hot compressions of two 5%Ni steels with and without niobium addition at different temperatures of 800-1 150℃and strain rates of 0.01-1s-1 were performed by using a Gleeble-3500 thermal simulator and the effect of niobium on the dynamic recrystallization （ DRX ） behavior was *** results showed that the niobium addition of 0.04% can retard DRX in 5%Ni steel significantly by increasing the activation energy for DRX from 394 to 462kJ / *** critical strain required for starting DRX in 5%Ni steel was increased by 0.04-0.10 with niobium addition when the steel was deformed at a strain rate of 0.01s-1 and temperatures varied from 950 to 1 000℃.The critical temperature required for starting DRX in 5%Ni steel was also increased from 1 000 to 1 050℃ with niobium addition when the steel was deformed at a strain rate of 0.1s-1 .Such a retarded DRX occurring in Nb-added 5%Ni steel can be attributed to the pinning effect of precipitates containing niobium.

关键词： 5%Ni steel dynamic recrystallization niobium precipitation pinning effect

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Interventional treatment for symptomatic acute-subacute portal and superior mesenteric vein thrombosis

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World Journal of Gastroenterology 2009年第40期15卷 5028-5034页

作者： feng-Yong Liu Mao-Qiang wang qing-Sheng Fan feng Duan Zhi-Jun wang Peng Song Department of Interventional Radiology Clinical Division of Internal Medicine Chinese People's Liberation Army General Hospital Beijing 100853 China

AIM: To summarize our methods and experience with interventional treatment for symptomatic acute-sub-acute portal vein and superior mesenteric vein throm-bosis (PV-SMV) thrombosis. METHODS: Forty-six patients (30 males, 16 females, aged 17-68 years) with symptomatic acute-subacute portal and superior mesenteric vein thrombosis were ac-curately diagnosed with Doppler ultrasound scans, com-puted tomography and magnetic resonance imaging. They were treated with interventional therapy, including direct thrombolysis (26 cases through a transjugular intrahepatic portosystemic shunt; 6 through percutane-ous transhepatic portal vein cannulation) and indirect thrombolysis (10 through the femoral artery to superior mesenteric artery catheterization; 4 through the radial artery to superior mesenteric artery catheterization). RESULTS: The blood reperfusion of PV-SMV was achieved completely or partially in 34 patients 3-13 d after thrombolysis. In 11 patients there was no PV-SMV blood reperfusion but the number of collateral vessels increased signif icantly. Symptoms in these 45 patients were improved dramatically without severe operationalcomplications. In 1 patient, the thrombi did not respond to the interventional treatment and resulted in intestinal necrosis, which required surgical treatment. In 3 patients with interventional treatment, thrombi reformed 1, 3 and 4 mo after treatment. In these 3 patients, indirect PV-SMV thrombolysis was performed again and was successful. CONCLUSION: Interventional treatment, including direct or indirect PV-SMV thrombolysis, is a safe and effective method for patients with symptomatic acutesubacute PV-SMV thrombosis.

关键词： Portal thrombosis Superior mesenteric vein thrombosis Thrombolysis Interventional treatment

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Kinetic Model of ε-Cu Particle Dissolution in Welding-Induced HAZ of Copper-Containing Steel

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Journal of Iron and Steel Research International 2008年第5期15卷 66-69页

作者： wang qing-feng CHAI feng CAI Jian-wei PAN Tao SU Hang State Key Laboratory of Metastable Materials Technology and Science Yanshan University Qinhuangdao 066004 Hebei China Division of Structural Material Research Central Iron and Steel Research Institute Beijing 100081 China College of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China

The kinetics of ε-Cu particle dissolution in the matrix of heat affected zone （HAZ） during welding of a copper-containing steel was determined by assembling the welding temperature-time program into a modified Whelan＇s solution. The particle dissolution dependence on the degree of ＂superheating＂ above the equilibrium transformation is demonstrated from the model. In terms of volume fraction of particle dissolution, the HAZ may he classified into three zones, including the undissolving zone, the partially dissolving zone, and the completely dissolving zone, respectively. The numerical solution was in good agreement with the experimental examination finding. The results of model can be used to quantitatively map the ε-Cu dissolution zone dependence on the peak temperature of welding thermal cycles and understand the evolution of this transformation during welding.

关键词： ε-Cu particle dissolution kinetics welding steel

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Phenotypic plasticity of floral traits and pollination adaption in an alpine plant Pedicularis siphonantha D. Don when transplanted from higher to lower elevation in Eastern Himalaya

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Journal of Mountain Science 2017年第10期14卷 1995-2002页

作者： DAI Wen-Kui AMBOKA Grace Mercy KADIORI Edwin Luguba wang qing-feng YANG Chun-feng Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences

Phenotypic plasticity and/or pollinatormediated selection may be responsible for the changes in floral traits of plants when they are forced to live in new conditions. Although the two events could be independent, we hypothesized that phenotypic plasticity in floral traits might help to coordinate plant-pollinator interactions and enhance plant reproductive success in changing habitats. To test this hypothesis, we investigated floral traits and pollination on three natural populations of a lousewort(Pedicularis siphonantha) ranging at different elevations, as well as two downward transplanted populations in Shangeri-La County and Deqin County, northwest Yunnan, China. The results indicated that floral traits, i.e. phenology, longevity,display size, corolla tube length and pollen production differed significantly among populations. Moreover,or the two transplanted populations, floral traits diverged from their original populations, but converged to their host populations. Although the phenotypic plasticity in floral traits might be a rapid response to abiotic factor such as warmer environment, the changes in floral traits were found to be well adapted to pollination environment of the host population. Compared with plants of their original habitats in higher elevation, the transplanted individuals advanced flowering time, shortened flower longevity, reduced floral display size and pollen production, received higher visiting frequency and yielded more seeds. These findings suggested that phenotypic plasticity of floral traits might help plants adjust their resource allocation strategy between preand post-pollination stages in response to harsh or temperate conditions, which might correspondingly meet a pollinator-poor or hyphen rich *** would be beneficial for the widely-distributed species to adapt to various environmental changes.

关键词： Alpine plant Bumble bee Pedicularis siphonantha Phenotypic plasticity in floral traits

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Synthesis and properties of novel calix[4]arene derivatives bearing fluorogenic coumarin units

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Chinese Chemical Letters 2008年第8期19卷 901-903页

作者： He Wen wang Ya qing feng Jin Qiang Xue Chan Xiao School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Four novel calix[4]arene derivatives 5-8 bearing four fluorogenic coumarin units attached via imino group acting also as binding sites at the upper rim have been prepared and characterized by IR, IH NMR and MS. Compounds 5-8 adopt a cone conformation. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy. Compounds 5, 6, 8 show selective recognition to Fe^3＋ and Cr^3＋.

关键词： Calixarenes Coumarin Imino Complexation

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Influence of Iron Ore Characteristics on FeO Formation During Sintering

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Journal of Iron and Steel Research International 2011年第5期18卷 5-10页

作者： WU Sheng-li wang qing-feng BIAN Miao-lian ZHU Juan LONG Fang-yi School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of iron ore characteristics on FeO formation during sintering was examined mainly in terms of chemical composition and the melting characteristics of iron ores. Statistical regression and X-ray diffraction were used to further explain the specific effect of iron ore characteristics on FeO formation. The results indicate that LOI （loss on ignition） in iron ores have a positive influence on FeO formation by promoting the sintering process of Fe2O3 decomposing and reducing. Silica contents in iron ores play a determining role in final content of FeO in sinter. The melting characteristics of iron ores significantly affect FeO formation during sintering.

关键词： iron ore characteristic chemical composition melting characteristic FeO formation

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Responses of bacterial strains isolated from drinking water environments to N-acyI-L-homoserine lactones and their analogs during biofilm formation

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Frontiers of Environmental Science & Engineering 2014年第2期8卷 205-214页

作者： Zhuoying WU1 qing wang, feng GUO Shenghua ZHANG Qipei JIANG Xin YU Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China

Often as a result ofbiofilm formation, drinking water distribution systems （DWDS） are regularly faced with the problem of microbial contamination. Quorum sensing （QS） systems play a marked role in the regulation of microbial biofilm formation; thus, inhibition of QS systems may provide a promising approach to biofilm formation control in DWDS. In the present study, 22 bacterial strains were isolated from drinking water-related environments. The following properties of the strains were investigated： bacterial biofilm formation capacity, QS signal molecule N-acyl-L-homoserine lactones （AHLs） production ability, and responses to AHLs and AHL analogs, 3-chloro-4-（dichloromethyl）-5-hydroxy-2（5H）- furanone （MX） and 2（5H）-furanone. Four AHLs were added to developed biofilms at dosages ranging from 0.1 nmol.L J to 100nmol.L1. As a result, the biofilm growth of more than 1/4 of the isolates, which included AHL producers and non-producers, were significantly promoted. Further, the biofilm biomasses were closely associated with respective AHLs concentrations. These results provided evidence to support the idea that AHLs play a definitive role in biofilm formation in many of the studied bacteria. Meanwhile, two AHLs analogs demon- strated unexpectedly minimal negative effects on biofilm formation. This suggested that, in order to find an applicable QS inhibition approach for biofilm control in DWDS, the testing and analysis of more analogs is needed.

关键词： drinking water distribution systems (DWDS) biofilm quorum sensing (QS) N-acyl-L-homoserine lac- tones (AHLs) (dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) 2(5H)-furanone

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