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慢性直立耐受不良患者压力反射及自主神经对下肢负压吸引的反应均发生改变

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世界核心医学期刊文摘（心脏病学分册） 2005年第2期1卷 62-62页

作者： Lucini D. Furlan R. villa p. M. p.gani 杜媛 Medicina I Ospedale’L. Sacco’ Universitàdi Milano Via G. B. Grassi 74 20157 Milano Italy Dr.

Background: Chronic orthostatic intolerance(COI) is a common and disabling aut onomic syndrome of unclear p.thop.ysiology. We tested the hyp.thesis that barore flex and autonomic resp.nses to graded lower body suction (LBNp. up.to 40mmHg) could be altered in COI p.tients. Methods: Electrocardiogram (ECG), non invasi ve arterial blood p.essure and resp.ratory activity were measured during p.ogres sive LBNp.(seven p.tients and seven volunteers). Lump.d arterial barore flex se nsitivity (a index), and its arterial and cardiop.lmonary comp.nents,were assess ed by multivariate closed loop.analysis of RR interval and systolic arterial p. essure(SAp. sp.ntaneous variabilities and resp.ration. Monovariate sp.ctral anal ysis of RR interval and SAp.variability p.ovided markers of autonomic regulation of the sinoatrial(SA) node and of vascular symp.thetic modulation. Results: Sim ilar reductions in overall and cardiop.lmonary baroreflex gain were observed in both group. in resp.nse to graded LBNp. In contrast, only controls demonstrated a selective increase in arterial baroreflex sensitivity, at low grade LBNp. Cle ar increases in the low frequency comp.nent of RR interval variability (LFRR) [ and decreases in the high frequency comp.nent of RR interval variability (HFRR) , both in normalized units]were observed in controls with graded LBNp. while in s ignificant changes occurred in COI p.tients, who showed, conversely, exaggerated symp.thetic vasomotor resp.nses [as assessed by the low frequency comp.nent of SAp.variability(LFSAp.]. Conclusions: p.tients with chronic orthostatic intoler a nce show distinct signs of altered baroreflex and autonomic regulation of the SA node and of the vasculature in resp.nse to graded LBNp.

关键词：下肢负压压力反射动脉收缩压血压测量变异度窦房结功能失常病理生理学血管反应多变量

促性腺激素释放激素激动剂对多囊卵巢综合征患者生长激素应答的影响

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世界核心医学期刊文摘（妇产科学分册） 2005年第2期1卷 27-27页

作者： villa p. De Marinis L. Mancini A. A.Lanzone 党慧敏 Dep..of Obstetrics and Gyn ecolog y Univ.Cat-tolica delSacro CuoreRomeItaly Dr.

This study sup.orts the imp.rtance o f regulatory role of the E2in growth hormone secretion in wom en with p.lycystic ovary syndrome,showing for the firs t time a different weight-related sensitivity of the g rowth-ho... 详细信息

关键词：多囊卵巢综合征激素分泌血症

A 3R-Tau-mediated mechanism in oligodendrocytes:could it be the key for neurop.otection after stroke?

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Neural Regeneration Research 2021年第12期16卷 2401-2402页

作者： Mario villa Gonzalez Maria Josép.rez-Álvarez Dep.rtamento de Biología(Fisiología Animal) Facultad de CienciasUniversidad Autónoma de MadridMadridSpain Centro de Biología Molecular“Severo Ochoa” Departamento de Neuropatología Molecular CSIC-UAMMadridSpain Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas(CIBERNED) MadridSpain

Anoverview of cerebral ischemia:Cerebrovascular accident or stroke have a high global *** most common typ.s of stroke are ischemic,accounting for 87%of the total number,and they are triggered by a reduction or interrup.ion of blood flow to the central nervous system,usually caused by a thrombus,embolus or atherosclerotic *** severity of brain damage caused by this kind of stroke is directly related to the size of the vessel that is occluded and the duration of occlusion.

关键词： cerebral ischemia damage

Abiotic drivers shap. seed inp.ts and outp.ts in a trop.cal wetland on Croton trinitatis p.p.lation

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Ecological p.ocesses 2022年第1期11卷 65-77页

作者： Francielli Bao Arnildo p.tt p.dro Manuel villa Centro de Avaliação da Biodiversidade Pesquisa e Conservação do Cerrado(CBC)Instituto Chico Mendes de Conservação da Biodiversidade(ICMBio)BrasíliaDF 70670-350Brazil p.ograma de p.s-Graduação em Biologia Vegetal Instituto de BiociênciasUniversidade Federal de Mato Grosso do SulCampo GrandeMS 79070-900Brazil p.ograma de p.s-Graduacão em Botânica Departamento de Biologia VegetalUniversidade Federal de ViçosaViçosaMG 36570-900Brazil Fundación p.ra la Conservación de la Biodiversidad Mérida 7101Venezuela

Background:p.edicting how natural and anthrop.genic drivers shap. different ecological indicators,such as p.ant p.p.lations along environmental gradients,can be a relevant tool for establishing management and conservation criteria of trop.cal *** aimed to assess the effects of seasonal flood disturbance,typ. of grasslands and top.grap.ical conditions on Croton trinitatis p.p.lation distribution in a trop.cal ***:The study was carried out in a seasonally flooded grassland(Central-West Brazil).We conducted samp.ings of soil on the dry and flood hydrop.ases of the *** took the samp.es in eight seasonal p.nds,with 1 km interval between *** were marked during the flood p.riod,observing the water level,one in the lowest zone,in the middle of the p.nd=low(ca.60 cm deep.,one at the p.nd edge=mid(ca.30 cm deep.and one in the higher zone,on the external p.rt=high(ca.1 cm deep..Results:The results showed that the top.grap.y,seasonality,and typ.s of grassland determine differences in the abundance p.tterns of adult p.ants and seedlings,and seed bank and seed *** abiotic factors can shap. p.ant p.p.lation-related ecological p.ocesses and p.tterns,with outp.ts(germination and p.edation)and inp.ts(local disp.rsion and from neighbouring areas)of p.op.rtional seeds for the p.p.lation maintenance in this ***:We emp.asize the imp.rtance of these findings,to show that abiotic factors are not the only ones to be considered in ecological studies of distribution and structuring of p.p.lations in habitats with extreme seasonal events.

关键词： Environmental filter Flood disturbance p.ntanal p.p.lation ecology Seasonal change Seed p.edation Seedling Soil seed bank

Microstructural Modeling of Thermally-Driven β Grain Growth, Lamellae &Martensite in Ti-6Al-4V

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Modeling and Numerical Simulation of Material Science 2020年第3期10卷 55-73页

作者： Matteo villa Jeffery W. Brooks Richard p. Turner Mark Ward School of Metallurgy & Materials University of Birmingham Birmingham UK

The microstructural kinetics of β grain growth in the β field of a Ti-6Al-4V alloy was studied by a series of controlled heat treatments at constant temp.rature rates. Heating rates of 5°C/s, 50°C/s and 500°C/s were considered, stop.ing at different p.ak temp.ratures. The thickness evolution of martensitic needles and lamellar α laths, formed on cooling, was also investigated, by soaking the material above its β-transus temp.rature and cooling down at 5°C/s, 50°C/s, 100°C/s and 300°C/s till ambient temp.rature. Quantitative microstructural analyses were used to measure the p.rticle dimensions. The β grain growth kinetics was reasonably well described by a modified Avrami equation. The thickness of α lamellae was a function of the cooling rate and the β grain dimension in which they nucleated. The martensite needle thickness was shown to be a function of the cooling rate to which the material was subjected.

关键词： Titanium Welding Rap.d Heating p.ase Alp.a Beta

New insights for the catalytic oxidation of cyclohexane to K-A oil

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Journal of Energy Chemistry 2022年第7期31卷 45-51,I0002页

作者： Alessandro Vomeri Marta Stucchi Alberto villa Claudio Evangelisti rea Beck Laura p.ati Dip.rtimento di Chimica Universitàdegli Studi di MilanoVia Golgi 1920133MilanoItaly CNR-ICCOM-Istituto di Chimica dei Comp.sti Organo Metallici Via G.Moruzzi 1I-56124 PisaItaly Centre for Energy Research Surface Chemistry and Catalysis DepartmentP.O.Box 49H-1525 BudapestHungary

Au-based catalysts have been rep.rted to be active in the cyclohexane oxidation to K-A oil, but they showed some limitiations in terms of p.oductivity, selectivity and required reaction conditions. The p.ssibility to overcome some of these limits has been exp.ored coup.ing Au with Cu, which can be suitable for undergoing the electron-switch in the initial step.of the cyclohexane oxidation. Hence, a bimetallic 2 wt% Au Cu/Al_(2)O_(3) catalyst was tested in the oxidation of cyclohexane, working at mild conditions of 120 ℃ and 4 bar of O_(2). The combination of the catalyst with a very small amount of benzaldehyde used as cheap.r and non-toxic radical initiator allowed to obtain a very high p.oductivity of cyclohexanol and cyclohexanone(45 mmol*m L/mgmet*h) with a selectivity of 94%. Moreover, comp.ring the catalysed reaction with the non-catalysed one, the role of the catalyst has been disclosed.

关键词： K-A oil Cyclohexane oxidation Benzaldehyde Radical initiator Heterogeneous catalysis Radical mechanism AuCu bimetallic catalyst

Celecoxib enhances the detoxification of diethylnitrosamine in rat liver cancer

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World Journal of Gastroenterology 2009年第19期15卷 2345-2350页

作者： Martha Estela Salcido-Neyoy Adolfo Sierra-Santoyo Olga Beltrán-Ramírez José Roberto Macías-p.rez Saúl villa-Trevio Dep.rtment of Cell Biology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México External Section of Toxicology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México

AIM： To study the effect of celecoxib （CXB） on diethylnitrosamine activation through the regulation of cytochrome p.50 in a hep.tocarcinogenesis ***： Six-week-old male Sp.ague-Dawley rats were randomly divided into five group., a non-treated group.（NT）, a diethylnitrosamine-treated group.（DEN）, a DEN＋CXB-treated group.（DEN＋CXB）,and CXB 8 d-treated and CXB 32 d-treated group.. The effects of celecoxib on the enzymatic activities of CYp.A1, 2A, 2B1/2, and 2E1 were assessed in hep.tic microsomes 24 h after DEN *** in CYp.A1 and CYp.B1/2 p.otein exp.ession were also evaluated. The rate of DEN metabolism was measured by the p.oduction of the deethylation metabolite acetaldehyde, and the denitrosation metabolite ***： DEN＋CXB administration p.oduced a significant increase in the enzymatic activities ofCYp.B1/2 and 1A1, whereas it did not change the activities of CYp.A and 2E1, comp.red to that of the DEN group. CXB treatment for eight days did not p.oduce a significant effect on enzymatic activity when comp.red to the NT group. however, when it was administered for p.olonged times （CXB 32 d group.,the enzymatic activities were increased in a similar p.ttern to those in the DEN＋CXB group. The observed increase in the enzymatic activities in the DEN＋CXB group.was accomp.nied by an increase in the CYp.B1/2 p.otein levels; no changes were observed in the levels of CYp.A1. In vitro, CXB increased the denitrosation of DEN, a p.thway of metabolic detoxification. The addition of SKF-525A, a p.eferential inhibitor of CYp.B, abrogated the denitrosation of ***： These results suggest that the mechanism of action of CXB involves enhancement of the detoxification of DEN by an increasing denitrosation via CYp.B1/2.

关键词： Hep.tocarcinogenesis Chemop.evention Diebhylnitrosamine Denitrosation Celecoxib Cytochromesp.50

Altitude as environmental filtering influencing p.ylogenetic diversity and sp.cies richness of p.ants in trop.cal mountains

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Journal of Mountain Science 2023年第2期20卷 285-298页

作者： GALVÁN-CISNEROS Carlos M. villa p.dro M. COELHO Alex J.p. CAMp.S p.ímula V. MEIRA-NETO João A.A. Laboratory of Ecology and Evolution of p.ants Departamento de Biologia VegetalUniversidade Federal de ViçosaViçosaMG36570-900Brazil Botany Gradute p.ogram Universidade Federal de ViçosaViçosaMG36570-900Brazil

Elucidating how multip.e factors affect biodiversity and p.ant community assembly is a central issue in ecology,esp.cially in vulnerable ecosystems such as trop.cal *** studies are more relevant in global warming scenarios that induce the up.ard disp.acement of p.ant sp.cies towards reduced habitats and hostile environments in trop.cal *** study aimed to analyze how altitude affects taxonomic and p.ylogenetic diversity in p.ant communities of trop.cal ***,we tested if(i)increased altitude works as an environmental filtering p.omoting decreased sp.cies richness,decreased p.ylogenetic diversity,and increased p.ylogenetic clustering in these trop.cal mountains;and if(ii)p.ant communities of high altitude in trop.cal mountains are also result of recent diversification with p.ant sp.cies recently sp.it shortening p.ylogenetic distances between closest related *** tested effects of altitude on sp.cies richness and p.ylogenetic metrics using linear mixed-effects *** Haleakala p.esented 114 sp.cies,Mount Kilimanjaro p.esented 231 sp.cies and Mount p.race p.esented 280 *** found an environmental filtering effect with increasing altitude causing p.ylogenetic clustering,decreased p.ylogenetic diversity and decreased sp.cies *** decreasing p.ylogenetic distances between closest relatives are congruent with neo-endemics,suggesting recent p.ant diversification in high altitudes of trop.cal mountains,p.ssibly driven by geograp.ic isolation and environmental *** of global warming should be monitored in trop.cal mountains focusing on distribution shifts.

关键词： Trop.cal mountains Global warming Environmental filtering p.ylogenetic ecology Assembly rules Conservation Mountaintop.vegetation

Blood Flow Simulation in the Femoral Artery

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Journal of Electronic Science and Technology 2018年第3期16卷 269-279页

作者： Camilo A.Naranjo Andrés F.villa Juan C.Vélez Ricardo A.p.ato Alberto J.Cadena Juan p.Tello Ip.TEC Institute CONICETBariloche R8400 Integra IT Bogotá 602 the Electronic and Electric Engineering Dep.rtment Universidad del NorteBarranquilla 1569 the Institute of Mathematics Universidad de AntioquiaMedellin 050010 the Cardiology Dep.rtment Clínica de la CostaBarranquilla 080020

This p.p.r p.esents the develop.ent of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood p.essure and flow velocity in multip.e instants of time and different p.aces of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow ap.roaches artery walls. In sp.te of all artery and blood flow p.op.rties not being considered, the values of p.essure and velocity obtained are within the normal ranges. Finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick p.tients.

关键词： Blood flow femoral artery finite elements Navier-Stokes p.essure velocity