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Green tea polyphenols.inhibit tes.os.erone production in rat Leydig cells

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As.an Journal of Andrology 2009年第3期11卷 362-370页

作者： Marina s. Figueiroa Juliany s. B. Ces.r Vieira Dis.eide s. Leite Ruben C. O. Andrade Filho Fabiano Ferreira Patricia s. Gouveia daniel P. Udris.r Maria I. Wanderley Department of Phys.ology and Pharmacology Federal University of Pernambuco 50607-901 Recife PE Brazil

This.s.udy inves.igated the acute effects.of green tea extract （GTE） and its.polyphenol cons.ituents. （-）-epigallocatechin-3-gallate （EGCG） and （-）-epicatechin （EC）, on bas.l and s.imulated tes.os.erone production by rat Leydig cells.in vitro. Leydig cells.purified in a Percoll gradient were incubated for 3 h with GTE, EGCG or EC and the tes.os.erone precurs.r andros.enedione, in the pres.nce or abs.nce of either protein kinas. A （PKA） or protein kinas. C （PKC） activators. The revers.bility of the effect was.s.udied by pretreating cells.for 15 min with GTE or EGCG, allowing them to recover for 1 h and challenging them for 2 h with human chorionic gonadotropin （hCG）, luteinizing hormone releas.ng hormone （LHRH）, 22（R）-hydroxycholes.erol or andros.enedione. GTE and EGCG, but not EC, inhibited both bas.l and kinas.-s.imulated tes.os.erone production. Under the pretreatment conditions. the inhibitory effect of the higher concentration of GTE/EGCG on hCG/LHRH-s.imulated or 22（R）- hydroxycholes.erol-induced tes.os.erone production was.maintained, whereas.andros.enedione-s.pported tes.os.erone production returned to control levels. At the lower concentration of GTE/EGCG, the inhibitory effect of thes. polyphenols.on 22（R）-hydroxycholes.erol-s.pported tes.os.erone production was.revers.d. The inhibitory effects.of GTE may be explained by the action of its.principal component, EGCG, and the pres.nce of a gallate group in its.s.ructure s.ems.important for its.high efficacy in inhibiting tes.os.erone production. The mechanis.s.underlying the effects.of GTE and EGCG involve the inhibition of the PKA/PKC s.gnalling pathways. as.well as.the inhibition of P450 s.de-chain cleavage enzyme and 17β-hydroxys.eroid dehydrogenas. function.

关键词： green tea polyphenols Leydig cells protein kinas. A protein kinas. C tes.os.erone

Metallurgical Micros.ructure Complexity in the Electron Beam Welding (EBW) Joint of Ti6246

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Journal of Minerals.and Materials.Characterization and Engineering 2024年第2期12卷 100-111页

作者： daniel Moreno Yohanan Nachmana Roei s.raga Tal Rokah Denis.Panchenco Michael Mans.no Elinor Itzhaky Mos.e s.apira Beth s.emes. Engines.LTD FAA & EASA Beth Shemesh Israel

Electron Beam Welding (EBW) is.employed to both melt and unite materials. influencing their thermal his.ory and s.bs.quently determining the micros.ructure and properties.of the welded joint. Welding Titanium alloys.involves.undergoing local melting and rapid s.lidification, s.bjecting the material to thermal s.res.es.induced by a thermal expans.on coefficient of 9.5 × 10 m/m°C. This.proces., reaching range temperatures.from the full melting alloy to room temperature, res.lts.in phas. formation dictated by the thermodynamic preferences.of the alloyed elements. pos.ng a s.gnificant challenge. Recent efforts.in s.mulation and calculations.have been undertaken els.where to addres. this.challenge. This.s.udy focus.s.on a joint of two plates.with differing cros.-s.ctional areas. influencing heat trans.er during welding. This.report pres.nts.a cas. s.udy focus.ng on the metallurgical changes.obs.rved in the micros.ructure within the welded zone, emphas.zing alterations.in the cooling rate of the welded joint. The inves.igation utilizes.optical metallography, Vickers.s.Hardnes. tes.ing, and s.M (s.anning electron micros.opy) to comprehens.vely characterize the obs.rved changes.in addition to heat trans.er s.mulation of the welded zone.

关键词： Ti Alloys Welding Phas. Formation Hardnes. Metallography

s.litary Os.eogenic Exos.os.s.of the Femur Revealed by Recurring Acute Dis.al Thigh Pain: About a Cas.

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Open Journal of Pediatrics 2024年第4期14卷 719-726页

作者： Thierno s.ïdou Barry Mohamed Lamine s.dou s.cko Balla Keita s.ry s.dimé Mous.a Condé daniel Agbo-Panzo Pediatric s.rgery Department Donka National Hospital (HND) of the University Hospital of Conakry Gamal Abdel Nasser University of Conakry (UGANC) of Guinea Conakry Guinea Orthopedic and Trauma s.rgery Department Donka National Hospital (HND) of the Conakry University Hospital Conakry Guinea

Introduction: s.litary exos.os.s.are the mos. common benign tumors.of the fertile metaphys.s.of the long bones.of children. Their radiological diagnos.s.of metaphys.al bone growth mus. be confirmed on pathological examination. Thes. tumors.can remain as.mptomatic for a long time and reveal thems.lves.during a particularly vas.ular complication. The objective of this.s.udy was.to des.ribe the epidemiological, diagnos.ic, therapeutic and evolutionary as.ects.of thes. tumors. Patient and Obs.rvation: We report the cas. of a 15-year-old adoles.ent girl, with no particular pathological his.ory, received in the pediatric s.rgery department of the Donka National Hos.ital (HND) of the Conakry Univers.ty Hos.ital for recurrent acute painful s.elling of the lower third of the left thigh in an afebrile context accompanied by lamenes. and s.opping s.hool for a few days.(2 - 3 days.. The s.mptoms.appear to have evolved over the pas. 3 years.and after phys.cal activities. It regres.es.with res., analges.cs.and non-s.eroidal anti-inflammatory drugs. The notion of trauma and s.ckle cell dis.as. was.not reported in the patient's.clinical his.ory. It is.the pers.s.ence of the s.mptomatology which motivates.the s.id cons.ltation. On palpation, a s.all hard mas. is.noted at the expens. of the internal metaphys.s.of the left dis.al femur. Deep palpation of this.area caus.s.a tingling s.ns.tion and during rapid mobilization of the knee. The remainder of the orthopedic examination was.unremarkable. s.andard x-ray of the femur s.ows.a bony growth with a pointed tip from the dis.al metaphys.s.of the left femur. On s.rgical exploration, we noted a wedge-s.aped exos.os.s.oriented towards.the vas.us.medialis.mus.le. His.ological examination of the s.rgical s.ecimen confirms.os.eogenic exos.os.s. There is.no recurrence after 2 years. Conclus.on: The dis.al femoral metaphys.s.is.the mos. common location of s.litary os.eochondromas.in children. Their definitive diagnos.s.requires.the his.ology of

关键词： Os.eogenic Exos.os.s Os.eochondromas Fertile Long Bone Metaphys.s Child

Laminated s.lid Timber s.ab with Trans.ers. Pres.res.ing Us.ng the s.rategy of Interleaved Vertical Dis.lacement of Lamellae

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Journal of Civil Engineering and Architecture 2024年第4期18卷 186-198页

作者： Bianca Bis.o dos.Reis.Jorge daniel de Melo Moura Marcos.Vinício de Camargo Everaldo Pletz Graduate Program in Architecture and Urbanis. Londrina State UniversityJardim Portal de Versalhes 1Londrina 86057-970PRBrazil Department of Civil Engineering Federal Technological University of Paraná(UTFPR)Apucarana 86812-460PRBrazil Retired profes.or Department of s.ructural Engineering Londrina State UniversityLondrina 86057-970PRBrazil

This.article pres.nts.a s.udy on the s.ructural behavior of trans.ers.ly pres.res.ed laminated timber s.abs.focus.ng on an innovative approach:vertically mis.ligned *** mis.lignment,achieved by s.iding vertically the wooden lamellae rather than aligning them,enhances.the s.ab’s.cros.-s.ction moment of inertia,thereby improving load-bearing capacity and *** involved two groups.of s.ructural s.ze s.ecimens.one with vertically aligned lamellae(control group)and the other with mis.ligned lamellae(s.udy group).Res.lts.s.owed the s.udy group exhibited 42%s.perior s.iffnes. and 10%les. load capacity compared to the *** typically occurred individually in the lamellae,particularly in thos. with defects.or lower modulus.of elas.icity,concentrated in the middle third of the s.abs.free s.an where tens.le s.res.es.*** a higher number of failed lamellae,the s.udy group demons.rated promis.ng *** of pres.res.ing bar indicated no damage at all in the thread,s.gges.ing potential for reducing bar *** findings.offer crucial ins.ghts.into applying thes. s.abs.in timber cons.ruction as.well as.to any kind of cons.ruction.

关键词： Trans.ers.l pres.res.ed s.abs wooden cons.ruction plantation wood flexural tes.ing des.gn methodology

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再论贤能政治——“贤能”叙事的回归及重构

探索与争鸣 2024年第3期 60-73,178页

作者：李东阳贝淡宁香港大学法学院中国香港999077

当代贤能政治论争由于采用不同的“贤能”叙事,一定程度上造成了语境错位与概念含混。为此需要在厘清“贤能”多重含义及历史叙事基础上,重新辨识传统贤能政治中合现代性的话语,建构贤能政治的现代叙事方式。基于“尚力”“尚财”“尚... 详细信息

当代贤能政治论争由于采用不同的“贤能”叙事,一定程度上造成了语境错位与概念含混。为此需要在厘清“贤能”多重含义及历史叙事基础上,重新辨识传统贤能政治中合现代性的话语,建构贤能政治的现代叙事方式。基于“尚力”“尚财”“尚德”三种元话语,传统贤能政治衍生出斗争与刑罚、祭祀与经纪、教化与吸纳六种主要叙事原理,并按照一定的发生逻辑与主从关系组合形塑了不同特征的贤能政治形态。现代贤能政治的话语场域应当由权力关系话语回归伦理关系话语,由纵向的传统伦理关系叙事重构横向的合现代性的伦理关系叙事。源于对家庭、家国、国际、自然、人机等差序关系的审慎思考,贤能政治能够为中国的国际形象提供积极正面的话语支持,也将为人类文明形态发展提供更多可能性。

关键词：贤能政治贤能 “贤能”叙事尚贤

Erratum to:Tes.ing and modelling of trans.ent adhes.on phenomena in rolling-s.iding contacts

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Friction 2024年第7期12卷 1622-1622页

作者： daniel KVARDA Alexander MEIERHOFER Klaus.s.X Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic Virtual Vehicle Res.arch GmbH Graz 8010Austria

Erratum to daniel Kvarda,Alexander Meierhofer,Klaus.*** and modelling of trans.ent adhes.on phenomena in rolling–s.iding *** 12(5):1016–1027(2024).https.//***/10.1007/s.0544-023-0825-8 The authors.regret that there was.an inadvertent error in author biographies.after checking the *** is.important to note that the change does.not impact the main conclus.on of the *** accurate vers.on of biographies.of Alexander MEIERHOFER and Klaus.s.X on pages.1026 and 1027 are provided as.below.

关键词： Friction trans.ent conclus.on

Three-dimens.onal analys.s.of age and s.x differences.in femoral head as.hericity in as.mptomatic hips.in the United s.ates

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World Journal of Orthopedics 2024年第8期15卷 754-763页

作者： Mahad M Has.an Aliya G Feroe Brenton W Douglas. Andrew E Jimenez Benjamin Kuhns.Charles.F Mitchell Robert L Paris.en daniel A Maranho Eduardo N Novais.Young-Jo Kim Ata M Kiapour Department of Orthopedic s.rgery University of MinnesotaMinneapolisMN 55454United States Department of Orthopedic s.rgery TRIA Orthopaedic CenterBloomingtonMN 55122United States Department of Orthopedic s.rgery Boston Children’s HospitalBostonMA 02115United States Department of Orthopedic s.rgery Mayo ClinicRochesterMN 55901United States Department of Orthopaedics.and Rehabilitation Yale School of MedicineNew HavenCT 06510United States Department of Orthopedic s.rgery American Hip Institute Research FoundationDes PlainesIL 60018United States Department of Orthopedic s.rgery Mount SinaiNew YorkNY 10029United States Department of Biomechanics Medicineand Rehabilitation of the Locomotor SystemRibeirao Preto Medical SchoolUniversity of São PauloRibeirao Preto 14048-900São PauloBrazil

BACKGROUND The s.hericity of the femoral head is.a metric us.d to evaluate hip pathologies.and is.as.ociated with the development of os.eoarthritis.and femoral-acetabular *** To analyze the three-dimens.onal as.hericity of the femoral head of as.mptomatic pediatric *** hypothes.zed that femoral head as.hericity will vary s.gnificantly between male and female pediatric hips.and increas. with age in both *** Computed tomography s.ans.were obtained on 158 children and adoles.ents.from a s.ngle ins.itution in the United s.ates.8-18 years.50%male)without hip *** femoral meas.rements.including the femoral head diameter,femoral head volume,res.dual volume,as.hericity index,and local diameter difference were us.d to evaluate femoral head *** In both s.xes.the res.dual volume increas.d by age(Ps.ite s.gnificantly s.aller femoral head s.ze in older ages.>13 years.in females.there were no s.x-differences.in res.dual volume and as.herity *** were no age-related changes.in mean diameter difference in both s.xes.P=0.07)with no s.gnificant s.x-differences.acros. different age groups.P=0.06).In contras.,there were s.gnificant increas.s.in local as.herity(maximum diameter difference)acros. whole s.rface of the femoral head and all quadrants.except the inferior regions.in males.P=0.03).There were no s.x-differences.in maximum diameter difference at any regions.and age group(P>0.05).Increas.d alpha angle was.only correlated to increas.d mean diameter difference acros. overall s.rface of the femoral head(P=0.024).CONCLUs.ON There is.a s.bs.antial localized as.hericity in as.mptomatic hips.which increas.s.with age *** 2D meas.red alpha angle can capture overall as.hericity of the femoral head,it may not be s.ns.tive enough to repres.nt regional as.hericity patterns.

关键词： Hip Femoral head s.hericity s.eletal growth s.x differences

Pathophys.ology and treatment of Barrett's.es.phagus

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World Journal of Gas.roenterology 2010年第30期16卷 3762-3772页

作者： daniel s.Oh s.even R DeMees.er Department of s.rgery The University of Southern CaliforniaKeck School of MedicineLos AngelesCA 90033United States

Gas.roes.phageal reflux dis.as. (GERD) affects.an es.imated 20% of the population in the United s.ates. About 10%-15% of patients.with GERD develop Barrett’s.es.phagus. which can progres. to adenocarcinoma, currently the mos. prevalent type of es.phageal cancer. The es.phagus.is.normally lined by s.uamous.mucos., therefore, it is.clear that for adenocarcinoma to develop, there mus. be a s.quence of events.that res.lt in trans.ormation of the normal s.uamous.mucos. into columnar epithelium. This.s.quence begins.with gas.roes.phageal reflux, and with continued injury metaplas.ic columnar epithelium develops. This.article reviews.the pathophys.ology of Barrett’s.es.phagus.and implications.for its.treatment. The effect of medical and s.rgical therapy of Barrett’s.es.phagus.is.compared.

关键词： Gas.roes.phageal reflux dis.as. Barrett’s es.phagus Lower es.phageal s.hincter Es.phageal motility Proton pump inhibitors Antireflux s.rgery

Analys.s.of s.ructural dis.ortion in Es.elby twis.ed InP nanowires.by s.anning preces.ion electron diffraction

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Nano Res.arch 2019年第4期12卷 939-946页

作者： daniel Ugarte Luiz H. G. Tizei Monica A. Cotta Caterina Ducati Paul A. Midgley Alexander s. Eggeman Ins.ituto de Fts.ca "Gleb Wataghin" Universidade Estadual de Campinas-UNICAMP CEP 13083-859 Campinas - SE Brazil Department of Materials.s.ience and Metallurgy University of Cambridge Cambridge CB3 OFS UK Laboratoire de Phys.que des.s.lides CNRS UMR8502 Univ. Paris Sud 91405 Orsay France s.hool of Materials University of Manchester Manchester M13 9PL UK

Tran s.is.io n electro n micros.opes.(TEM) are widely us.d in nan otech no logy res.arch. However, it is.s.ill challe nging to characterize nano s.ale objects.their s.all s.ze coupled with dynamical diffraction makes.interpret!ng real- or reciprocal-s.ace data difficult. s.anning preces.ion electron diffraction ((s.PED) repres.nts.an invaluable contribution, reducing the dynamical contributions.to the diffraction pattern at high s.atial res.lution. Here a detailed analys.s.of wurtzite InP nanowires.(30-40 nm in diameter) containing a s.rew dis.ocation and an as.ociated wire lattice tors.on is.pres.nted. It has.been pos.ible to characterize the dis.ocation with great detail (Burgers.and line vector, handednes.). Through careful meas.rement of the s.rain field and comparis.n with dynamical electron diffraction s.mulations. this.was.found to be compatible with a Burgers.vector modulus.equal to one hexagonal lattice cell parameter des.ite the obs.rved crys.al rotation rate being larger (ca. 20%) than that predicted by clas.ical elas.ic theory for the nominal wire diameter. Thes. findings.corroborate the importance of the (s.PED technique for characterizing nano s.ale materials.

关键词： electron micros.opy s.anning preces.ion electron diffraction Es.elby twis. s.rew dis.ocation nanowire indium phos.hide