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protective effect of ascorbic acid in experimental gastric cancer: reduction of oxidative stress

World Journal of gastroenterology 2003年第3期9卷 446-448页

作者： Claudia p.M.S.Oliveira paulo Kassab Fabio p.Lopasso Heraldo p.Souza Mariano Janiszewski Francisco R.M.Laurindo Kioshi Iriya Antonio A.Laudanna Department of gastroenterology of Medical School of University of So paulo (USp) So PauloBrazil Department of Emergency Medicine of Mcdical School of University of So paulo (USp) So PauloBrazil Heart Institute of Medical School of University of So paulo (USp) So PauloBrazil Depatment of pathology of Medical School of University of So paulo (USp) So PauloBrazil

AIM;Oxidative stress participates in the cell carcinogenesis by inducing DNA *** aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing ROS(Reactive Oxygen Species)generation in experimental gastric carcinoma in a rat model. METHODS:Experimental gastric cancer was induced in twelve Wistar male rats(weighting 250-350 g)by profound duodeno-gastric reflux throught split *** rats were allocated to the following groups:group Ⅰ(n=6) was the control;group Ⅱ(n=6)which was mantained with daily intake of tape water with Vitamin C(30 mg/Kg).After 6 or 12 months,samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups. Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with *** histopathologic confirmation of adenocarcinoma was made by eosin- hemathoxilin method. RESULTS:The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰ whereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of *** cancers were located in the anastomosis in all *** luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/×10~6(mean±SD)and 14.9±4.0 count per minute/mg/×10~6,respectively,in group Ⅰ and Ⅱ animals(p g in tumor tissues but not in non neoplasic mucosa. CONCLUSION:Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric *** reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic ***,it may have a role in the prevention of gastric carcinoma. Oliveira CpMS Kassab p Lopasso Fp Souza Hp Janiszewski M Laurindo FRM Iriya K Laudanna *** effect of ascorbic acid in experimental gastric cancer:reduction of oxidative *** J g

关键词： Animals Antioxidants Ascorbic Acid Male Oxidative Stress Rats Rats, Wistar Stomach Neoplasms control

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Energy spectrum of cosmic protons and helium nuclei by a hybrid measurement at 4300 m a.s.l.

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Chinese physics C 2014年第4期38卷 25-31页

作者： B.Bartoli p.Bernardini 毕效军 I.Bolognino p.Branchini A.Budano A.K.Calabrese Melcarne p.Camarri 曹臻 R.Cardarelli S.Catalanotti 陈松战陈天禄 p.Creti 崔树旺戴木忠 A.D'Amone 单增罗布 I.De Mitri B.D'Ettorre piazzoli T.Di girolamo g.Di Sciascio 冯存峰冯朝阳冯振勇苟全补郭义庆何会海胡海兵胡红波 M.Iacovacci R.Iuppa 贾焕玉拉巴次仁厉海金 g.Liguori 刘成刘俊刘茂元卢红马玲玲马欣华 g.Mancarella S.M.Mari g.Marsella D.Martello S.Mastroianni p.Montini C.C.Ning M.panareo B.panico L.perrone p.pistilli F.Ruggieri p.Salvini R.Santonico S.N.Sbano 沈培若盛向东石峰 A.Surdo 谭有恒 p.Vallania S.Vernetto C.Vigorito 王辉吴超勇吴含荣薛良杨群羽杨先楚姚志国袁爱芳查敏张慧敏张力张学尧张勇赵静扎西次仁扎西桑珠周勋秀祝凤荣朱清棋 g.Zizzi 白云翔陈明君陈垚冯少辉高博顾旻皓侯超李晓晓刘佳刘加丽王旭肖刚张丙开张寿山周斌左雄 Dipartimento di Fisica dell’Università di Napoli "Federico II" Complesso Universitario di Monte Sant’Angelovia Cinthia Istituto Nazionale di Fisica Nucleare Sezione di Napoli Complesso Universitario di Monte Sant’Angelovia Cinthia Dipartimento di Matematica e Fisica "Ennio De giorgi" Università del Salento via per Arnesano Istituto Nazionale di Fisica Nucleare Sezione di Lecce via per Arnesano Key Laboratory of particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Dipartimento di Fisica dell’Università di pavia via Bassi 627100 Pavia Italy Istituto Nazionale di Fisica Nucleare Sezione di Pavia via Bassi 627100 Pavia Italy Istituto Nazionale di Fisica Nucleare Sezione di Roma Tre via della Vasca Navale 8400146 Roma Italy Istituto Nazionale di Fisica Nucleare-CNAF Viale Berti-Pichat 6/240127 Bologna Italy Dipartimento di Fisica dell’Università di Roma "Tor Vergata" via della Ricerca Scientifica Istituto Nazionale di Fisica Nucleare Sezione di Roma Tor Vergata via della Ricerca Scientifica Tibet University Hebei Normal University Yunnan University Shandong University Southwest Jiaotong University Dipartimento di Fisica dell’Università "Roma Tre" via della Vasca Navale 8400146 Roma Italy Osservatorio Astrofisico di Torino dell’Istituto Nazionale di Astrofisica via P.Giuria 110125 Torino Italy Istituto Nazionale di Fisica Nucleare Sezione di Torino via P.Giuria 110125 Torino Italy Dipartimento di Fisica dell’Università di Torino via P.Giuria 110125 Torino Italy physics Department Kunming University Normal College of Fuyang

The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called ＂knee＂ by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive plate Chamber （RpC） array of the ARgO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic ray components by using a multi-parameter technique. A highly uniform energy resolution of about 25% is achieved throughout the whole energy range （100-700 TeV）. The observed energy spectrum is compatible with a single power law with index γ=-2.63±0.06.

关键词： Cherenkov telescope ARgO-YBJ energy spectrum hybrid measurement composition

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贡嘎山东坡的鸟类多样性和区系

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四川动物 2017年第6期36卷 601-615页

作者：吴永杰何兴成 Shane g.DuBay Andrew Hart Reeve per Alstrom 周华明和梅香雍凡张文文雷富民冉江洪四川大学生命科学学院生物资源与生态环境教育部重点实验室成都610065 Department of Ecology and Evolution University of ChicagoChicago 60637USA Committee on Evolutionary Biology University of ChicagoChicago 60637USA Life Sciences Section Integrative Research CenterField Museum of Natural HistoryChicago 60605USA Biosystematics Section at the Natural History Museum of Denmark University of CopenhagenCopenhagen DK-2100Denmark Department of Ecology and genetics Animal EcologyEvolutionary Biology CentreUppsala UniversityNorbyv?gen 18DSE-752 36 UppsalaSweden 中国科学院动物研究所动物进化与系统学院重点实验室北京100101 甘孜藏族自治州林业科学研究所四川康定626001 环境保护部南京环境科学研究所国家环境保护生物安全重点实验室南京210042

经过7年5次野外系统调查并综合有关文献,贡嘎山东坡分布有鸟类336种,其中,留鸟204种(60.7%),夏候鸟89种(26.5%),冬候鸟18种(5.4%),旅鸟25种(7.4%);东洋界物种205种(61.0%),古北界物种105种(31.3%),广布种26种(7.7%);雀形目passeriformes鸟类245种(72.9%);繁殖鸟类293种(87.2%)。本地区有国家Ⅰ级重点保护鸟类3种,国家Ⅱ级重点保护鸟类29种;横断山-喜马拉雅地区特有鸟类53种;CITES附录Ⅰ鸟类3种,附录Ⅱ鸟类25种;世界自然保护联盟濒危物种红色名录濒危鸟类1种,易危鸟类2种。研究发现,东洋界物种的海拔分布下限平均、上限平均、中点平均和海拔跨度平均都低于古北界物种,但仅海拔分布中点平均和上限平均差异有统计学意义(p<0.05),体现了东洋界和古北界物种对高海拔环境适应能力的不同可能与其不同的生物地理演化历史有关;东洋界占优势的特有种(51/53)海拔分布下限平均、中点平均和上限平均显著高于非特有物种,体现出东洋界特有种对高山环境的适应也许与其特有化过程有关。贡嘎山东坡鸟类丰富度在中海拔1 800~2 800 m的落叶阔叶混交林和针阔叶混交林中最高,在高海拔和低海拔物种丰富度较低,物种丰富度呈中峰模式,鸟类生态群落随植物群落结构变化而呈现一定的垂直生态替代规律。

关键词：鸟类区系生物多样性横断山海螺沟海拔调查

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Allometric prediction of above-ground biomass of eleven woody tree species in the Sudanian savanna-woodland of West Africa

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Journal of Forestry Research 2010年第4期21卷 475-481,524页

作者： Louis Sawadogo patrice Savadogo Daniel Tiveau Sidzabda Djibril Dayamba Didier Zida Yves Nouvellet per Christer Oden Sita guinko Institut de l'Environnement et de Recherches Agricoles Département Productions Forestières Swedish University of Agricultural Sciences Faculty of Forest SciencesSouthern Swedish Forest Research Centre Ambassade de Suède 93Avenue Roi BaudouinKinshasa-GombeRépublique Démocratique du Congo Consulat général de France à pointe Noire (Congo) Valise Diplomatique 128 bis rue de l'Université 75351 paris 07 Sp France Université de Ouagadougou Unité de Formation et Recherche en Sciences de la Vie et de la Terre

Allometric models are necessary for estimating biomass in terrestrial ecosystems. generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We developed species-specific allometric models to predict aboveground biomass for 11 native tree species of the Sudanian savanna- woodlands. Diameters at the base and at breast height, with species means ranging respectively from 11 to 28 cm and 9 to 19 cm, and the height of the trees were used as predictor variables. Sampled trees spanned a wide range of sizes including the largest sizes these species can reach. As a response variable, the biomass of the trees was obtained through destructive sampling of 4 754 trees during wood harvesting. We used a stepwise multiple regression analysis with backward elimination procedure to develop models separately predicting, total biomass of the trees, stem biomass, and biomass of branches and twigs. All species- specific regression models relating biomass with measured tree dimen- sions were highly significant （p 〈 0.001）. The biomass of branches and twigs was less predictable compared to stem biomass and total biomass, although their models required fewer predictors and predictor interac- tions. The best-fit equations for total above-ground biomass and stem biomass bad R2 〉 0.70, except for the Acacia species; for branches including twig biomass, R2-values varied from 0.749 for Anogeissus leiocarpa to 0.183 for Acacia macrostachya. The use of these equations in estimating available biomass will avoid destructive sampling, and aid in planning for sustainable use of these species.

关键词： allometry above-ground biomass indigenous woody species linear regression site specific equation

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Catabolic Response profiles, Catabolic Uniformity and Richness as Microbiological Indicators in a Soil of pergamino, Buenos Aires province, with and without previous Application of glyphosate

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Journal of Agricultural Chemistry and Environment 2016年第2期5卷 85-91页

作者： Ruth p. Ríos Lidia giuffré Romina I. Romaniuk Mónica g. pérez Eduardo A. pagano School of Agriculture University of Buenos Aires Buenos Aires Argentina

Incubation assay in trays was performed with two soils with different application histories of glyphosate: no application, and previous application. The soils used were Typic Argiudolls of pergamino, province of Buenos Aires, and the treatments were: control (no application), and 20, 200 and 2000 mg of active ingredient per kg of soil. Sampling was performed at the beginning (T0) and 45 days after (T45). Catabolic response profiles (CRp), catabolic richness and catabolic uniformity were determined according to the methodology based on measuring the differences in respiration induced by substrate in a short time (4 hours). The substrates used in this study were 20, namely, two amines, 5 aminoacids, two carbohydrates, and 11 carboxylic acids. The objective of this work was to compare soils with different histories of application of glyphosate, measuring its effect on catabolic response profiles, catabolic uniformity and catabolic richness. In this study, no differences were observed between catabolic richness among the different sampling times and doses of glyphosate applied. glyphosate application affected the structure of the soil microbial communities. At the end of the test, soils with all doses of previous herbicide application showed greater catabolic uniformity than soils without previous application.

关键词： glyphosate Catabolic Response profiles Catabolic Uniformity and Richness

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Development and Validation of a Method for Simultaneous Determination of Metformin and Saxagliptin in a Formulation by Rp-HpLC

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American Journal of Analytical Chemistry 2015年第11期6卷 841-850页

作者： p. B. N. prasad K. Satyanaryana g. Krishnamohan Central Drugs Testing Laboratory CDSCO Hyderabad India NATCO pharma R&D Hyderabad India Deparment of pharmacy JNTUH Hyderabad India

A simple, specific, sensitive, precise and accurate reverse phase high performance liquid chromatographic method (Rp-HpLC) was developed for the simultaneous analysis of Metformin and Saxagliptin in active pharmaceutical ingredients (ApIs) as well as in marketed tablet (combination) dosage forms. The method was achieved on Enable C18 g (250 × 4.6 mm;5 μm particle size) column using 0.05 M KH2pO4 buffer (pH 4.5):Methanol:Acetonitrile (60:20:20 %v/v) as a mobile phase at a flow rate of 0.6 mL/min and by employing UV detection at 220 nm wavelength. The retention time of Metformin and Saxagliptin were found to be 4.38 min and 6.92 min, respectively. The method was validated as per ICH guidelines. The limit of detection (LOD) and limit of quantification (LOQ) of Metformin were found to be 0.112 μg/mL and 0.373 μg/mL, respectively, while those of Saxagliptin were found to be 0.029 μg/mL and 0.096 μg/mL, respectively. The method was found to be rapid, sensitive, linear, specific, accurate, precise and economic for the quality control and stability assays of Metformin and Saxagliptin in marketed tablet dosage forms.

关键词： Metformin Saxagliptin Simultaneous Analysis Rp-HpLC Stress Induced Degradation

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Surface properties of Fe_4N Compounds Layer on AISI 4340 Steel Modified by pulsed plasma Nitriding

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Journal of Materials Science & Technology 2013年第3期29卷 287-290页

作者： J.C.Díaz-guillén g.Vargas-gutiérrez E.E.granda-gutiérrez J.S.Zamarripa-pia S.I.pérez-Aguilar J.Candelas-Ramírez L.lvarez-Contreras Centro de Investigacin en Materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investigacin en Materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investigacin y Estudios Avanzados del IpN Unidad SaltilloCarretera Saltillo Monterrey km 13Apdo.Postal 663C.P.25000 SaltilloCoahuilaMexico

In this work, the effect of nitriding current density on hardness, crystalline phase composition, layer thickness and corrosion rate of AlSl 4340 steel has been studied. X-ray diffraction analysis shows that thin layers formed during nitriding process are constituted of 7-Fe4N for samples processed between 1 and 2.5 mA/cm2. Thickness of nitrided layer increases proportionally to current density （0 μm for 0.5 mA/cm2 to 15 pm for 2.5 mA/cm2）. plasma nitriding increased the surface hardness from 300 HV50g for untreated sample, to around 800HV5og for nitrided samples at 1 mA/cm2. While the untreated samples exhibited a corrosion rate of 0.153 mm per year, the corrosion performance was improved up to 0.03 mm per year at current densities above 1 mA/cm2, which is about one fifth of the corrosion rate of the untreated sample.

关键词： plasma nitriding Current density Hardness Corrosion

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Utilization of over matured fruit waste of Spine gourd(Momordica dioca Roxb.)as a source of anthelmintic bioactive constituents

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Food Bioscience 2022年第3期47卷 1007-1015页

作者： H.B.Rashmi p.S.Negi Fruit and Vegetable Technology CSIR-Central Food Technological Research InstituteMysore570 020India

To study the difference in the accumulation of bioactive constituents in Spine gourd(Momordica dioica Roxb.),the changes in its phenolic compounds at mature green(fruit utilized)and ripe red(fruit wasted)stages were analysed,and it was correlated with their antioxidant and anthelmintic *** highest total phenolic content was observed in ripe peel ethyl acetate(RpEA),tannins in ripe seed hexane(RSH)and flavonoid in ripe peel ethanol(RpE)***–MS analysis identified 15 phenolic compounds in the *** highest antioxidant potential was shown by RSH in DppH(IC_(50)1.47 mg/ml),RpEA in ABTS(IC_(50)2.40 mg/ml),and mature peel water(MpeW)extract in FRAp assays(0.58μg trolox equivalent per g dw).RpE induced the highest anthelmintic activity against Caenorhabditis elegans in egg hatch assay(LC_(50)-0.02 mg/ml),and adult worm mortality assay(LC_(50)-1.44 mg/ml),as well as 100%death of infective juveniles in Heterorhabditis indica(50 mg/ml).Correlation studies and principal Component Analysis(pCA)indicated the relationship of catechins,quercetin,kaempferol,rutin,and gallic acid to anthelmintic *** study showed that the ripe stage of Spine gourd,which gets disposed of as postharvest waste,had better anthelmintic activity,and it can be utilized for the development of food formulations with anthelmintic potential.

关键词： Anthelmintic Antioxidant Caenorhabditis elegans Heterorhabditis indica phenolics

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A Cilia-inspired Closed-loop Sensor-actuator Array

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Journal of Bionic Engineering 2018年第3期15卷 526-532页

作者： James g. H. Whiting Richard Mayne Chris Melhuish Andrew Adamatzky Unconventional Computing Centre and Bristol Robotics Laboratory University of the West of England Bristol UK

Cilia are finger-like cell-surface organelles that are used by certain varieties of aquatic unicellular organisms for motility, sensing and obj ect manipulation. Initiated by internal generators and external mechanical and chemical stimuli, coordinated undulations of cilia lead to the motion of a fluid surrounding the organism. This motion transports micro-particles towards an oral cavity and provides motile force. Inspired by the emergent properties of cilia possessed by the pond organism p. caudatum, we propose a novel smart surface with closed-loop control using sensor-actuators pairings that can manipulate objects. Each vibrating motor actuator is controlled by a localised microcontroller which utilises proximity sensor information to initiate actuation. The circuit boards are designed to be plug-and-play and are infinitely up-scalable and reconfigurable. The smart surface is capable of moving objects at a speed of 7.2 millimetres per second in forward or reverse direction. Further development of this platform will include more anatomically similar biomimetic cilia and control.

关键词： bioinspiration artificial cilia object manipulation sorting platforms

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Quantification of hookworm ova from wastewater matrices using quantitative pCR

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Journal of Environmental Sciences 2017年第7期29卷 231-237页

作者： pradip gyawali Warish Ahmed Jatinder p.Sidhu paul Jagals Simon Toze CSIRO Land and Water Ecosciences Precinct School of public Health The University of Queensland

A quantitative pCR（q pCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge *** estimated the average gene copy numbers for a single ovum using a mixed population of *** average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in *** seeded and unseeded wastewater and sludge *** newly developed qp CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated *** qp CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,*** further application of the q pCR assay for the quantification of *** ova was determined by seeding a known numbers of ova into the wastewater *** qp CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of *** gene *** conversion of the q pCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,*** result of this study indicated that qp CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qp CR generated data for health risk assessment.

关键词： Wastewater matrices Quantitative pCR Hookworm ova Health risks

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