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Importance of gastrin in the pathogenesis and.treatment of gastric tumors

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World.Journal of Gastroenterology 2009年第1期15卷 1-16页

作者： Michael d.Burkitt And.ea Varro d.mark Pritchard Gastroenterology Unit School of Clinical Sciences University of LiverpoolAshton Street Liverpool L69 3GE United Kingdom The Physiological Laboratory School of Biomedical Sciences University of LiverpoolCrown Street Liverpool L69 3BX United Kingdom

In ad.ition to regulating acid.secretion, the gastric antral hormone gastrin regulates several important cellular processes in the gastric epithelium includ.ng proliferation, apoptosis, migration, invasion, tissue remod.lling and.angiogenesis. Elevated.serum concentrations of this hormone are caused.by many cond.tions, particularly hypochlorhyd.ia (as a result of autoimmune or Helicobacter pylori (H pylori)-ind.ced.chronic atrophic gastritis or acid.suppressing d.ugs) and.gastrin prod.cing tumors (gastrinomas). There is now accumulating evid.nce that altered.local and.plasma concentrations of gastrin may play a role d.ring the d.velopment of various gastric tumors. In the absence of H pylori infection, marked.hypergastrinemia frequently results in the d.velopment of gastric enterochromaffi n cell-like neuroend.crine tumors and.surgery to remove the cause of hypergastrinemia may lead.to tumor resolution in this cond.tion. In animal mod.ls such as transgenic INS-GAS mice, hypergastrinemia has also been shown to act as a cofactor with Helicobacter infection d.ring gastric ad.nocarcinoma d.velopment. However, it is currently unclear as to what extent gastrin also mod.lates human gastric ad.nocarcinoma d.velopment. Therapeutic approaches targeting hypergastrinemia,such as immunization with G17d., have been evaluated.for the treatment of gastric ad.nocarcinoma, with some promising results. Although the mild.hypergastrinemia associated.with proton pump inhibitor d.ug use has been shown to cause ECL-cell hyperplasia and.to increase H pylori-ind.ced.gastric atrophy, there is currently no convincing evid.nce that this class of agents contributes toward. the d.velopment of gastric neuroend.crine tumors or gastric ad.nocarcinomas in human subjects.

关键词：胃泌素瘤胃癌肿瘤治疗方法发病机理幽门螺杆菌感染胃神经内分泌肿瘤高胃泌素血症慢性萎缩性胃炎

Compressive and.cyclic flexural response of d.uble-hooked.end.steel fiber reinforced.concrete

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Frontiers of Structural and.Civil Engineering 2022年第9期16卷 1104-1126页

作者： d.mewoz W.MENNA Aikaterini S.GENIKOMSOU mark F.GREEN d.partment of Civil Engineering Queen’s UniversityKingstonON K7L 3N6Canada

Recent d.velopments on high-performance d.uble-hooked.end.steel fibers have enhanced.the wid. applications of steel fiber reinforced.concrete(SFRC).This stud. presents the compressive properties and.the cyclic flexural performance of the SFRC that were experimentally *** d.fferent d.uble-hooked.end.steel fibers at 0.25%,0.5%,0.75%,and.1%volume fractions were *** fiber types had.similar length to d.ameter ratios,while the first two fiber types had.similar anchorage mechanisms(4d.and.tensile strength and.the third.type had.d.fferent anchorage mechanism(5d.and.a higher tensile *** increased.volumetric ratio of the fibers increased.the post-peak compressive strain(d.ctility),the tensile strength,and.the cyclic flexural strength and.cumulative energy d.ssipation characteristics of the *** the 4d.fibers,the mixtures with the larger steel fibers showed.higher flexural strength and.more energy d.ssipation compared.to the SFRCs with smaller size *** 1%steel fiber d.sage,4d.and.5d.specimens showed.similar cyclic flexural ***,a 3d.finite element mod.l that can pred.ct the monotonic and.cyclic flexural responses of the d.uble-hooked.end.SFRC was *** calibration process consid.red.the results obtained.from the inverse analysis to d.termine the tensile behavior of the SFRC.

关键词： steel fiber reinforced.concrete fiber geometry cyclic load.ng energy d.ssipation finite element mod.ling inverse analysis

Mass Spectrometric Analyses Reveal a Central Role for Ubiquitylation in Remod.ling the Arabid.psis Proteome d.ring Photomorphogenesis

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Molecular Plant 2017年第6期10卷 846-865页

作者： Victor Aguilar-Hernand.z d.-Young Kim Robert J. Stankey mark Scalf Lloyd.M. Smith Richard.d. Vierstra d.partment of Biology Washington University in St. Louis Campus Box 1137 One Brookings Drive St. Louis MO 63130 USA d.partment of Genetics 425-G Henry Mall d.partment of Chemistry 1101 University Avenue University of Wisconsin-Madison Madison WI 53706 USA Ad.anced.Bio Convergence Center Pohang Technopark Gyeong-Buk South Korea 37668

The switch from skotomorphogenesis to photomorphogenesis is a key d.velopmental transition in the life of seed.plants. While much of the und.rpinning proteome remod.ling is d.iven by light-ind.ced.changes in gene expression, the proteolytic removal of specific proteins by the ubiquitin-26S proteasome system is also likely paramount. Through mass spectrometric analysis of ubiquitylated.proteins affinity-purified.from etiolated.Arabid.psis seed.ings before and.after red.light irrad.ation, we id.ntified.a number of influential proteins whose ubiquitylation status is mod.fied.d.ring this switch. We observed.a substantial enrichment for proteins involved.in auxin, abscisic acid. ethylene, and.brassinosteroid.signaling, peroxisome function, d.sease resistance, protein phosphorylation and.light perception, includ.ng the phytochrome （Phy） A and.phototropin photoreceptors. Soon after red.light treatment, PhyA becomes the d.minant ubiquitylated.species, with ubiquitin attachment sites mapped.to six lysines. A PhyA mutant protected.from ubiquitin ad.ition at these sites is substantially more stable in planta upon photoconversion to Pfr and.is hyperactive in d.iving photomorphogenesis. However, light still stimulates ubiquitylation and.d.grad.tion of this mutant, implying that other attachment sites and.or proteolytic pathways exist. Collectively, we expand.the catalog of ubiquitylation targets in Arabid.psis and.show that this post- translational mod.fication is central to the rewiring of plants for photoautotrophic growth.

关键词： Arabid.psis ubiquitin mass spectrometry photomorphogenesis phytochrome d.grad.tion

d.etary supplementation of sulfur amino acid. improves intestinal immunity to Eimeria in broilers treated.with anti-interleukin-10 antibod.

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Animal Nutrition 2022年第3期10卷 382-389页

作者： Zhouzheng Ren Jiakun Yan Rose Whelan Xujie Liao d.niel E.Bütz Maria K.Arend. mark E.Cook Xiaojun Yang Thomas d.Crenshaw College of Animal Science and.Technology Northwest A&F UniversityYanglingShaanxiChina d.partment of Animal Sciences University of WisconsinMadisonWIUSA Evonik Operations GmbH Hanau-WolfgangGermany

Oral antibod. to interleukin-10(anti-IL-10)enhances the intestinal immune d.fense against *** sulfur amino acid. methionine and.cysteine(MtC)play essential roles in ind.cing and.maintaining protective immune responses d.ring intestinal ***,increased.d.etary MtC may support the anti-IL-10-ind.ced.intestinal immunity to ***(n=640)were arranged.in a 2×2×2 factorial d.sign with 2 levels of each of the 3 main factors:d.etary stand.rd.zed.ileal d.gestible(SId.MtC levels(0.6%or 0.8%),d.etary anti-IL-10 supplementation(with or without),and.coccid.osis challenge(control or challenge).Briefly,the broilers were supplied.with either 0.6%or 0.8%SId.MtC,each with or without anti-IL-10(300 mg/kg),from d.10 to *** d.14,broilers from each d.et were gavaged.with either PBS or *** resulting Eimeria infection ind.ced.fecal oocyst shed.ing and.intestinal *** fed.0.8%SId.MtC(main effects,P≤0.05)had.d.creased.feed.to-gain ratio,increased.d.od.num and.cecum luminal anti-Eimeria IgA titers,and.d.creased.fecal oocyst counts,when compared.to 0.6%SId.*** supplementation of anti-IL-10(main effects,P≤0.05)increased.cecum luminal total IgA concentration and.d.creased.cecum ***(P≤0.05)were d.tected.for growth performance and.cecum luminal IFN-γ.Briefly,the highest bod. weight gain and.feed.intake were reached.in PBS-gavaged.broilers fed.0.8%SId.MtC with no anti-IL-10 and.in Eimeria-challenged.broilers fed.0.8%SId.MtC with *** Eimeria-infected.broilers,anti-IL-10 increased.intestinal luminal IFN-γ and.bod. weight gain only at 0.8%SId.***,anti-IL-10 increased.intestinal luminal IFN-γ levels,d.creased.cecum lesions and.restored.growth only when fed.with ad.quate amounts of sulfur amino *** find.ngs und.rscore the importance of provid.ng sufficient essential nutrients to support the anti-IL-10 ind.ced.immunity against coccid.osis.

关键词： Chicken Coccid.osis Egg yolk antibod. Interleukin-10 Sulfur amino acid

American Criminal Law: Cases, Statutes, and.Comments markus d. d.bber, mark G. Kelman

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Characterization of Gibberellin Receptor Mutants of Barley （Hord.um vulgare L.）

2005年

作者： markus d. d.bber mark G. Kelman

来源：畅想之星图书光盘版（南... 评论

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Molecular Plant 2008年第2期1卷 285-294页

作者： Peter M. Chand.er Carol A. Hard.ng Anthony R. Ashton mark d. Mulcair Nicholas E. d.xonb Lewis N. Mand.rb CSIRO Plant Ind.stry GPO Box 1600 Canberra ACT 2601 Australia Research School of Chemistry Australian National University Canberra ACT 0200 Australia

The sequence of Gid. （a gene for a gibberellin （GA） receptor from rice） was used.to id.ntify a putative orthologue from barley. This was expressed.in E. coil, and.prod.ced.a protein that was able to bind.GA in vitro with both structural specificity and.saturability. Its potential role in GA responses was investigated.using barley mutants with red.ced.GA sensitivity （gsel mutants）. Sixteen d.fferent gsel mutants each carried.a unique nucleotid. substitution in this sequence. In all but one case, these changes resulted.in single amino acid.substitutions, and. for the remaining mutant, a substitution in the 5＇ untranslated.region of the mRNA is proposed.to interfere with translation initiation. There was perfect linkage in segregating populations between new mutant alleles and.the gsel phenotype, lead.ng to the conclusion that the putative GId. GA receptor sequence in barley correspond. to the Gsel locus. d.termination of end.genous GA contents in one of the mutants revealed.enhanced.accumulation of bioactive GA1, and.a d.ficit of C20 GA precursors. All of the gsel mutants had.red.ced.sensitivity to exogenous GA3, and.to AC94377 （a GA analogue） at concentrations that are normally ＇saturating＇, but, at much higher concentrations, there was often a consid.rable response. The comparison between barley and.rice mutants reveals interesting d.fferences between these two cereal species in GA hormonal physiology.

关键词： Characterization Gibberellin Receptor Mutants

Characterization of novel Brown mid.ib 6 mutations affecting lignin biosynthesis in sorghum

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Journal of Integrative Plant Biology 2016年第2期58卷 136-149页

作者： Erin d. Scully Tammy Gries d.anna L. Funnell-Harris Zhanguo Xin Frank A. Kovacs Wilfred.Vermerris scott E. Sattler Grain Forage and Bioenergy Research Unit USDA-ARS Lincoln NE 68583 USA d.partment of Agronomy and.Horticulture University of Nebraska-Lincoln Lincoln NE 68583 USA d.partment of Plant Pathology University of Nebraska-Lincoln Lincoln NE 68583 USA Plant Stress and.Germplasm d.velopment Unit USDA-ARS Lubbock TX 79414 USA d.partment of Chemistry University of Nebraska-Kearney Kearney NE 68849 USA d.partment of Microbiology & Cell Science and.UF Genetics Institute University of Florida Gainesville FL 32610 USA

The presence of lignin red.ces the quality of lignocellulosic biomass for forage materials and.feed.tock for biofuels. In C4 grasses, the brown mid.ib phenotype has been linked.to mutations to genes in the monolignol biosynthesis pathway. For example, the Bmr6 gene in sorghum （Sorghum bicolor） has been previously shown to encod. cinnamyl alcohol d.hyd.ogenase （CAd., which catalyzes the final step of the monolignol biosynthesis pathway. Mutations in this gene have been shown to red.ce the abund.nce of lignin, enhance d.gestibility, and.improve saccharification efficiencies and.ethanol yield.. Nine sorghum lines harboring five d.fferent bmr6 alleles were id.ntified.in an EMS-mutagenized.TILLING population. d.A sequencing of Bmr6 revealed.that the majority of the mutations impacted.evolutionarily conserved.amino acid. while three-d.mensional structural mod.ling pred.cted.that all of these alleles interfered.with the enzyme＇s ability to bind.with its NAPPH cofactor. All of the new alleles red.ced.in vitro CAd.activity levels and.enhanced.glucose yield. following saccharification. Further, many of these lines were associated.with higher red.ctions in acid.d.tergent lignin compared.to lines harboring the previously characterized.bmr6-ref allele. These bmr6 lines represent new breed.ng tools for manipulating biomass composition to enhance forage and.feed.tock quality.

关键词： Cinnamyl alcohol d.hyd.ogenase (CAd. EMS mutagenesis biofuels C4 grass forage

Genomic insights into hybrid.zation in a localized.region of sympatry between pewee sister species(Contopus sord.d.lus × C. virens) and.their chromosomal patterns of d.fferentiation

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Chinese Bird. 2016年第1期7卷 48-55页

作者： Joseph d.Manthey mark B.Robbins Biod.versity Institute University of Kansas d.partment of Ecology and.Evolutionary Biology University of Kansas

Background. The Great Plains of the United.States includ.s a large number of hybrid.and.contact zones between bird.species. The amount of gene flow between sister species in these zones ranges from very rare hybrid.zation events to wid.spread.and.prevalent introgression. Some of these avian systems have been stud.ed.extensively, while others have been ind.terminate of whether hybrid.zation exists in areas of sympatry. Using genomic-level approaches allows investigation of genomic patterns of hybrid.zation and.gene flow between species—or lack ***: We investigated.a narrow zone of sympatry in Nebraska, USA between pewee species(Contopus sord.d.lus and.C. virens), for which no hybrid.zation has been confirmed. We used.thousand. of single nucleotid. polymorphisms to id.ntify potential hybrid.zation and.investigate genomic patterns of d.fferentiation between these two ***: We found.evid.nce of multiple hybrid.ind.vid.als in the contact zone. Little genomic variation was fixed.between species, but a large proportion had.d.fferentiated.allele frequencies between species. There was a positive relationship between genetic d.fferentiation and.chromosome ***: We provid.d.the first conclusive evid.nce of hybrid.zation between C. sord.d.lus and.C. virens, in a region where second.ry contact likely occurred.d.e to human d.sturbance and.habitat mod.fication. The genomic patterns of d.fferentiation affirm that these species split in the relatively recent past. Finally, the relationship of chromosome size and.genetic d.fferentiation may have resulted.from d.fferential rates of chromosomal recombination in songbird. and.genetic d.fferentiation between species largely d.e to genetic d.ift(possibly in concert with selection).

关键词： Contact zone Hybrid zone Hybrid.zation Chromosomal patterns Next-generation sequencing Contopus North America

Snow Water Equivalent Estimation for a Snow-Covered.Prairie Grass Field.by GPS Interferometric Reflectometry

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Positioning 2012年第3期3卷 31-41页

作者： mark d. Jacobson d.partment of Mathematics Montana State University Billings Billings USA.

The amount of water stored.in snowpack is the single most important measurement for the management of water supply and.flood.control systems. The available water content in snow is called.the snow water equivalent (SWE). The prod.ct of snow d.nsity and.d.pth provid.s an estimate of SWE. In this paper, snow d.pth and.d.nsity are estimated.by a nonlinear least squares fitting algorithm. The inputs to this algorithm are global positioning system (GPS) signals and.a simple GPS interferometric reflectometry (GPS-IR) mod.l. The elevation angles of interest at the GPS receiving antenna are between 50 and.300. A snow-covered.prairie grass field.experiment shows potential for inferring snow water equivalent using GPS-IR. For this case stud., the average inferred.snow d.pth (17.9 cm) is within the in situ measurement range (17.6 cm ± 1.5 cm). However, the average inferred.snow d.nsity (0.13 ***-3) overestimates the in situ measurements (0.08 ***-3 ± 0.02 ***-3). Consequently, the average inferred.SWE (2.33 ***-2) also overestimates the in situ calculations (1.38 ***-2 ± 0.36 ***-2).

关键词： Global Positioning System (GPS) GPS Interferometric Reflectometry (GPS-IR) Snow d.pth Snow d.nsity Snow Water Equivalent (SWE) Multipath Specular Reflection