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中国有色金属学会会刊：英文版 2010年第S3期20卷 837-841页

作者： E.P.MASUKU H.MLLER U.A.CURLE P.C.PISTORIUS Materials Science and Manufacturing Council for Scientific Industrial ResearchPretoriaSouth Africa department of Materials Science and Engineering Carnegie Mellon UniversityPittsburghUSA

The corrosion behavior(in chloride medium) of the surface layer of SSM-HPDC plates of alloys 7075-T6 and 2024-T6 was compared with that of the wrought alloys 7075-T6 and *** testing was performed in deaerated 3.5%NaCl *** separate tests,the open-circuit potential was monitored in aerated 3.5% NaCl for 30 min after *** electrochemical tests show that there is no significant difference in the pitting potential of the wrought alloys and that of the Cu-enriched surfaces of the SSM-HPDC alloys.

关键词： semi-solid metal(SSM) forming wrought aluminium alloys alloy 7075 alloy 2024 corrosion surface liquid segregation

Chemical composition and antioxidant activity of certain Morus species

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 973-980页

作者： Mohammad IMRAN Hamayun KHAN Mohibullah SHAH Rasool KHAN Faridullah KHAN Institute of Chemical Sciences University of Peshawar department of Chemistry Islamia College University Pakistan council of Scientific & Industrial Research (PCSIR) Laboratories Complex

In the present work,the fruits of four Morus species,namely Morus alba (white mulberry),Morus nigra (black mulberry),Morus laevigata (large white fruit),and Morus laevigata (large black fruit),were analyzed for proximate composition,essential minerals,and antioxidant *** this purpose,the ripe fruits were collected from the northern regions of *** major nutritional components moisture,ash,lipids,proteins,fibres,carbohydrates,and total sugar) were found to be in the suitable range along with good computed *** dry weight,pH,and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g,(3.20±0.07)–(4.78±0.15),and (0.84±0.40)%–(2.00±0.08)%,*** riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits,while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW).The mulberry fruits were rich with regard to the total phenol and alkaloid contents,having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW,*** quantities of essential macro-(K,Ca,Mg,and Na) and micro-(Fe,Zn,and Ni) elements were found in all the fruits.K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g,while Ca,Na,and Mg contents were (440±3.21)–(576±7.37),(260±3.86)–(280±3.50),and (240±3.51)–(360±4.20) mg/100 g,*** decreasing order of micro-minerals was Fe>Zn>*** radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective *** on the results obtained,mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.

关键词： Mulberry fruits Chemical composition 2 2-diphenyl-l-picrylhydrazyl (DPPH) radical scavenging activity Nutritional value. Pakistan

Nature-derived compounds modulating Wnt/β-catenin pathway:a preventive and therapeutic opportunity in neoplastic diseases

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Acta Pharmaceutica Sinica B 2020年第10期10卷 1814-1834页

作者： Gianluca Sferrazza Marco Corti Gloria Brusotti Pasquale Pierimarchi Caterina Temporini Annalucia Serafino Enrica Calleri department of Drug Sciences University of PaviaPavia 27100Italy Institute of Translational Pharmacology National Research Council of ItalyRome 03018Italy

The Wnt/β-catenin signaling is a conserved pathway that has a crucial role in embryonic and adult *** of the Wnt/β-catenin pathway has been associated with diseases including cancer,and components of the sisnaling have been proposed as innovative therapeutic targets,mainly for cancer *** attention of the worldwide researchers paid to this issue is increasing,also in view of the therapeutic potential of these agents in diseases,such as Parkinson’s disease(PD),for which no cure is existing *** evidence indicates that abnormal Wnt/β-catenin signaling is involved in tumor immunology and the targeting of Wnt/β-catenin pathway has been also proposed as an attractive strategy to potentiate cancer *** the last decade,several products,including naturally occurring dietary agents as well as a wide variety of products from plant sources,including curcumin,quercetin,berberin,and ginsenosides,have been identified as potent modulators of the Wnt/β-catenin signaling and have gained interest as promising candidates for the development of chemopreventive or therapeutic drugs for *** this review we make an overview of the nature-derived compounds reported to have antitumor activity by modulating the Wnt/β-catenin signaling,also focusing on extraction methods,chemical features,and bio-activity assays used for the screening of these compounds.

关键词： Wnt/β-catenin pathway Nature-derived compounds Anticancer therapy Cancer prevention

Propulsion tests on ultra-high-temperature ceramic matrix composites for reusable rocket nozzles

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Journal of Advanced Ceramics 2023年第7期12卷 1345-1360页

作者： Diletta Sciti Antonio Vinci Luca Zoli Pietro Galizia Simone Failla Stefano Mungiguerra Giuseppe D.Di Martino Anselmo Cecere Raffaele Savino Institute of Science Technology and Sustainability for Ceramics-National Research CouncilFaenza 48018Italy department of Industrial Engineering University of Naples Federico IINaples 80125Italy

Ultra-high-temperature ceramic matrix composites(UHTCMCs)based on a ZrB_(2)/SiC matrix have been investigated for the fabrication of reusable nozzles for *** de Laval nozzle prototypes,obtained by sintering with either hot pressing(HP)or spark plasma sintering(SPS),were tested 2-3 times in a hybrid rocket motor for proving *** were extracted after oxidation tests to study the microstructural changes and oxidative and thermomechanical stresses induced by the repeated *** to a reference graphite nozzle,no measurable erosion was observed for the UHTCMC-based *** oxidation mechanism consisted in the formation of a ZrO_(2)intermediate layer,with a liquid silicon oxide(SiO_(2))layer on the surface that was displaced by the action of the gas flux towards the divergent part of the nozzle,protecting it from further *** specimens obtained by HP and SPS displayed similar performance,with very slight differences,which were attributed to small changes in *** tests demonstrated the capability of complex-shaped prototypes made of the developed UHTCMCs to survive repeated exposure to environments representative of a realistic space propulsion application,for overall operating time up to 30 s,without any failure nor measurable erosion,making a promising step towards the development of reusable rocket components.

关键词： ultra-high-temperature ceramics(UHTCs) ceramic matrix composites(CMCs) propulsion oxidation resistance nozzle prototypes

Effect of snow on mountain river regimes： an example from the Pyrenees

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Frontiers of Earth Science 2017年第3期11卷 515-530页

作者： Alba SANMIGUEL-VALLELADO Enrique MORAN-TEJEDA Esteban ALONSO-GONZALEZ Juan Ignacio LOPEZ-MORENO Pyrenean Institute of Ecology CSIC (Spanish Research Council) Zaragoza Spain department of Geography University of the Balearic Islands Palma de Mallorca Spain

The purpose of this study was to characterize mountain river regimes in the Spanish Pyrenees and to assess the importance of snow accumulation and snowmelt on the timing of river flows. Daily streamflow data from 9 gauging stations in the Pyrenees were used to characterize river regimes. These data were analyzed by hydrological indices, with a focus on periods when snow accumulation and snowmelt occurred. These results were combined with data on Snow Water Equivalent （SWE）（from measure- ments of depth and density of snow in the main river basins and also simulated by a process-based hydrological model）, snowmelting （simulated by a process-based hydrological model）, precipitation （from observations）, and temperature （from observations）. Longitude. and elevation gradients in the Pyrenees explain the transition of river regimes from those that mostly had low nival signals （in the west and at low elevations） to those that mostly had high nival signals （low winter runoff and late spring peakflow, in the east and at high elevations）. Although trend analyses indicated no statistically signifi- cant changes, there was a trend of decreased nival signal over time in most of the analyzed rivers. Our results also demonstrated that snow processes cannot explain all of the interannual variability of river regimes, because the temporal distribution of liquid precipitation and tempera- ture play key roles in hydrography.

关键词： river regime precipitation snow indices,Spanish Pyrenees streamflow

Repurposing drugs to target nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2019年第15期25卷 1783-1796页

作者： Silvia Sookoian Carlos J Pirola department of Clinical and Molecular Hepatology National Scientific and Technical Research Council (CONICET) University of Buenos Aires Institute of Medical Research (IDIM) department of Molecular Genetics and Biology of Complex Diseases National Scientific and Technical Research Council (CONICET) University of Buenos Aires Institute of Medical Research (IDIM)

Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological *** is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.

关键词： Drug discovery Drug repositioning Fibrosis Genetics Treatment Systems biology

Mouse models in male fertility research

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Asian Journal of Andrology 2011年第1期13卷 139-151页

作者： Duangporn Jamsai Moira K O＇Bryan department of Anatomy and Developmental Biology The Australian Research Council （ARC） Centre of Excellence in Biotechnology and Development Monash University Melbourne Victoria 3800 Australia

Limited knowledge of the genetic causes of male infertility has resulted in few treatment and targeted therapeutic options. Although the ideal approach to identify infertility causing mutations is to conduct studies in the human population, this approach has progressed slowly due to the limitations described herein. Given the complexity of male fertility, the entire process cannot be modeled in vitro. As such, animal models, in particular mouse models, provide a valuable alternative for gene identification and experimentation. Since the introduction of molecular biology and recent advances in animal model production, there has been a substantial acceleration in the identification and characterization of genes associated with many diseases, including infertility. Three major types of mouse models are commonly used in biomedical research, including knockoutJknockin/gene-trapped, transgenic and chemical-induced point mutant mice. Using these mouse models, over 400 genes essential for male fertility have been revealed. It has, however, been estimated that thousands of genes are involved in the regulation of the complex process of male fertility, as many such genes remain to be characterized. The current review is by no means a comprehensive list of these mouse models, rather it contains examples of how mouse models have advanced our knowledge of post-natal germ cell development and male fertility regulation.

关键词： infertility male fertility mouse models spermatogenesis

ABCB1 and ABCB19 auxin transporters have synergistic effects on early and late Arabidopsis anther development

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Journal of Integrative Plant Biology 2015年第12期57卷 1089-1098页

作者： Valentina Cecchetti Patrizia Brunetti Nadia Napoli Laura Fattorini Maria Maddalena Altamura Paolo Costantino Maura Cardarelli IBPM-CNR Institute of Molecular Biology and Pathology National Research Council Sapienza University of Rome department of Biology and Biotechnology Sapienza University of Rome department of Environmental Biology Sapienza University of Rome

Arabidopsis abcbl abcb19 double mutants defective in the auxin transporters ABCB1/PGP1 and ABCB19/PGP19 are altered in stamen elongation, anther dehiscence and pollen maturation. To assess the contribution of these transporters to stamen development we performed phenotypic, histological analyses, and in situ hybridizations on abcbl and abcbl9 single mutant flowers. We found that pollen maturation and anther dehiscence are precocious in the abcbl but not in the abcb19 mutant. Accordingly, endothecium ligniflcation is altered only in abcbl anthers. Both abcbl and abcb1 abcb19 stamens also show altered early development, with asynchronous anther Iocules and a multilayer tapetum. DAPI staining showed that the timing of meiosis is asynchronous in abcbl abcb19 anther Iocules, while only a small percentage of pollen grains are non- viable according to Alexander＇s staining. In agreement, TAM （TARDY ASYNCHRONOUS MEIOSIS）, as well as BAM2 （BARELY ANY MERISTEM）involved in tapetal cell development--areoverexpressed in abcbl abcb19 young flower buds. Corre- spondingly, ABCB1 and ABCB19 mRNA localization supports the observed phenotypes of abcbl and abcbl abcb19 mutant anthers. In conclusion, we provide evidence that auxin transport plays a significant role both in early and late stamen development： ABCB1 plays a major role during anther development, while ABCB19 has a synergistic role.

关键词： Anther development Arabidopsis auxin transport endothecium lignification tapetum differentiation

Conventional, but not remote ischemic preconditioning, reduces iNOS transcription in liver ischemia/reperfusion

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World Journal of Gastroenterology 2014年第28期20卷 9506-9512页

作者： Bergthor Bjornsson Anders Winbladh Linda Bojmar Tommy Sundqvist Per Gullstrand Per Sandstrom department of Surgery County Council of Ostergotland58185 Linkoping Sweden department of Clinical and Experimental Medicine Faculty of Health SciencesLinkping University58185 Linkoping Sweden

AIM:To study the effects of preconditioning on inducible nitric oxide synthase(iNOS)and interleukin 1(IL-1)receptor transcription in rat liver ischemia/reperfusion injury(IRI).METHODS:Seventy-two male rats were randomized into 3 groups:the one-hour segmental ischemia(IRI,n=24)group,the ischemic preconditioning(IPC,n=24)group or the remote ischemic preconditioning(RIPC,n=24)*** IPC and R-IPC were performed as 10 min of ischemia and 10 min of *** iNOS and the IL-1 receptor mRNA in the liver tissue was analyzed with real time *** total Nitrite and Nitrate(NOx)in continuously sampled microdialysate(MD)from the liver was *** addition,the NOx levels in the serum were ***:After 4 h of reperfusion,the iNOS mRNA was significantly higher in the R-IPC(ΔCt:3.44±0.57)group than in the IPC(ΔCt:5.86±0.82)group(P=0.025).The IL-1 receptor transcription activity was reduced in the IPC group(ΔCt:1.88±0.53 to 4.81±0.21),but not in the R-IPC group,during reperfusion(P=0.027).In the MD,a significant drop in the NOx levels was noted in the R-IPC group(12.3±2.2 to 4.7±1.2μmol/L)at the end of ischemia compared with the levels in early ischemia(P=0.008).A similar trend was observed in the IPC group(11.8±2.1 to 6.4±1.5μmol/L),although this difference was not statistically *** levels of NOx rose quickly during reperfusion in both ***:IPC,but not R-IPC,reduces iNOS and IL-1 receptor transcription during early reperfusion,indicating a lower inflammatory *** is consumed in the ischemic liver lobe.

关键词： Ischemia-reperfusion injury Preconditioning Remote preconditioning Liver ischemia Liver surgery Microdialysis Nitric oxide Inducible nitric oxide synthase Interleukin-1 receptor

Comparative studies of elemental composition in leaves and flowers of Catharanthus roseus growing in Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2016年第1期6卷 50-54页

作者： Shahin Aziz Koushik Saha Nasim Sultana Husna Parvin Nur Md.Aminul Ahsan Shamim Ahmed Md.Kamal Hossain Chemical Research Division BCSIR department of Chemistry Jahangirnagar University Bangladesh council of Scientific and Industrial Research (BCSIR) Laboratories

Objective:To investigate the elemental composition of the leaves and flowers of Catharanthus roseus(***) due to the plant's wide application in the indigenous medicinal system and its chemical constituents' ***:The atomic absorption spectrophotometer was used for quantitative analysis of various ***:Total 13 important elements were analyzed in leaves and flowers of *** indicated the presence of Na,K,Ca,Mg,Cr,Fe,Zn,Al,Cu,Ni,Pb,Cd and Mn in both leaves and *** most important finding of the work was that,leaves of *** showed high concentration of all elements except K and Zn while flowers of *** showed higher concentration of K and ***:The elemental composition in both leaves and flowers of *** were found to be ***,different parts of this medicinal plant are enriched in some micro and macro nutrients like Fe,Ca,Na,K,Zn,which are very important for biological metabolic system as well as human health.

关键词： Bangladesh Catharanthus roseus Indigenous medicinal systems Atomic absorption spectrophotometer Elemental composition