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Journal of Earth Science 2024年

作者： FLORES Daniel Germán OCA?A Raúl Emmanuel MELIáN Edgardo ORTEG Andrés ESPER ANGILLIERI maría Yanina PITTALUGA maría alejandra CIGEOBIO (CONICET-UNSJ) Av.José I.de la Roza y Meglioli Gabinete de Geología Ambiental， INGEO， Universidad Nacional de San Juan， Av.José I.de la Roza y Meglioli

The Monte Desert is characterized by a great diversity of landforms created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determine whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landforms， and 2: define whether morphometric， soil and surface properties influence vegetation patterns along alluvial landscape. Morphometric data were obtained by processing a 5 m digital elevation model. The coverage of rock fragments， fine sediments and mulch was quantified. Observations and descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegetation properties were calculated using a Point Quadrat Method. The relationship between variables was evaluated through multivariate statistical analysis. The main results show the presence of 45 plant species distributed in 19 families， where shrubs are dominant. The wind effect， topographic wetness and dissection of the landscape are limiting factors of diversity. The coverage of superficial rock fragments influence vegetation coverage through the distribution and availability of rainwater. Furthermore， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and development of vegetation in the early stages of growth.

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Effects of Phytoremediation on Soil Contaminated with Pb and Cd in Tolerant Bacterial Populations

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Journal of Environmental Science and Engineering(A) 2024年第4期13卷 122-127页

作者： alejandra Vásquez maría Montes Melissa Cervantes maría Alvarado Pedro García Victor Aguilar Department of Environmental Engineering Institute for EngineeringUniversity of VeracruzBoca del RioVer.94294Mexico Department Chemical Engineering Faculty of Chemical SciencesUniversity of VeracruzBoca del RíoVer.94294Mexico Faculty of Environmental Engineering Popular Autonomous University of the State of PueblaBarrio de Santiago 72410PueblaPueMexico Department of Administration Open Education SystemUniversity of VeracruzBoca del RioVer.94294Mexico

Bacterial populations isolated from treated soil,artificially contaminated with lead(Pb)and cadmium(Cd)and undergoing a phytoremediation process were studied to determine their potential application in soil *** physicochemical parameters evaluated in the soil varied *** bacterial strains were selected from each polluted soil to test tolerance and growth in contaminated *** concentrations of heavy metals tested were 1,000 ppm for lead and 850 ppm for *** strains were morphologically identified through Gram *** strains showing the most significant growth in both contaminants were then selected to verify their tolerance to different concentrations of heavy *** results demonstrated that the selected bacteria have high tolerance to Pb,resisting inhibition up to 2,000 *** contrast,strains exposed to cadmium tended to slow their growth as the concentration increased.

关键词： Lead cadmium soil bacteria remediation

From liver to hormones:The endocrine consequences of cirrhosis

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World Journal of Gastroenterology 2024年第9期30卷 1073-1095页

作者： Juan Eduardo Quiroz-Aldave Elman Rolando Gamarra-Osorio maría del Carmen Durand-Vásquez Luciana del Pilar Rafael-Robles Jhean Gabriel Gonzáles-Yovera maría alejandra Quispe-Flores Luis Alberto Concepción-Urteaga Alejandro Román-González José Paz-Ibarra marcio José Concepción-Zavaleta Non-communicable Diseases Endocrinology Research LineHospital de Apoyo ChepénChepén 13871Peru Department of Endocrinology Hospital Víctor Lazarte EchegarayTrujillo 13006Peru Department of Endocrinology Clínica Javier PradoLima 15046Peru Department of Gastroenterology Hospital Nacional Guillermo Almenara IrigoyénLima 15018Peru Department of Endocrinology Hospital de Emergencias GrauLima 15001Peru Internal Medicine Hospital Regional Docente de TrujilloTrujillo 13011Peru Department of Endocrinology Hospital Universitario de San Vicente FundaciónMedellin 050010Colombia Internal Medicine Universidad de AntioquiaMedellín 050010Colombia School of Medicine Universidad Nacional Mayor de San MarcosLima 15081Peru Department of Endocrinology Hospital Nacional Edgardo Rebagliati MartinsLima 15072Peru Carrera de Medicina Humana Universidad Científica del SurLima 15067Peru

Hepatocrinology explores the intricate relationship between liver function and the endocrine *** liver diseases such as liver cirrhosis can cause endocrine disorders due to toxin accumulation and protein synthesis *** its importance,assessing endocrine issues in cirrhotic patients is frequently *** article provides a comprehensive review of the epidemiology,pathophysiology,diagnosis,and treatment of endocrine disturbances in liver *** review was conducted using the PubMed/Medline,EMBASE,and Scielo databases,encompassing 172 *** cirrhosis is associated with endocrine disturbances,including diabetes,hypoglycemia,sarcopenia,thyroid dysfunction,hypogonadotropic hypogonadism,bone disease,adrenal insufficiency,growth hormone dysfunction,and secondary *** optimal tools for diagnosing diabetes and detecting hypoglycemia are the oral glucose tolerance test and continuous glucose monitoring system,*** can be assessed through imaging and functional tests,while other endocrine disorders are evaluated using hormonal assays and imaging *** options include metformin,glucagon-like peptide-1 analogs,sodium-glucose co-transporter-2 inhibitors,and insulin,which are effective and safe for diabetes *** standards are followed for managing hypoglycemia,and hormone replacement therapy is often necessary for other endocrine *** transplantation can address some of these problems.

关键词： Diabetes mellitus Hypoglycemia Thyroid diseases Hypogonadism Metabolic bone diseases Liver cirrhosis

The Iberian Roma Population Variant Server(IRPVS)

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Journal of Genetics and Genomics 2024年第7期51卷 769-773页

作者： Fabiola Mavillard Javier Perez-Florido Francisco M.Ortuño Amador Valladares Miren L.Álvarez-Villegas Gema Roldán Rosario Carmona Manuel Soriano Santiago Susarte Pilar Fuentes Daniel López-López Ana maría Nuñez-Negrillo alejandra Carvajal Yolanda Morgado Daniel Arteaga Rosa Ufano Pablo Mir Juan F.Gamella Joaquín Dopazo Carmen Paradas Macarena Cabrera-Serrano Instituto de Biomedicina de Sevilla(IBiS) Hospital Universitario Virgen del Rocío/CSIC/Universidad de SevillaSevillaSpain Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas(CIBERNED) Instituto de Salud CarlosⅢSevillaSpain Plataforma Andaluza de Medicina Computacional Fundación Progreso y Salud(FPS)Hospital Virgen del RocíoSevillaSpain Grupo de medicina computacional de sistemas Instituto de Biomedicina de Sevilla(IBiS)Hospital Virgen del RocíoSevillaSpain Nodo de Genómica Funcional (INB-ELIXIR-es)Fundación Progreso y Salud(FPS)Hospital Virgen del RocíoSevilla 41013Spain Bioinformática en Enfermedades raras(BiER) Centro de Investigación Biomédica en Red de Enfermedades Raras(CIBERER)Instituto de salud CarlosⅢSevillaSpain Departamento de Ingeniería de Computadores Automática y RobóticaUniversidad de GranadaGranadaSpain Servicio de Urgencias de Atención Primaria Distrito SevillaSevillaSpain Centro de Servicios Sociales Negociado de Servicios EspecializadosAyuntamiento de SevillaSevillaSpain Departamento de Enfermería Facultad de Ciencias de la SaludUniversidad de GranadaGranadaSpain Departamento de Neurología Hospital Virgen de las NievesGranadaSpain Departamento de Neurología Hospital Virgen de ValmeSevillaSpain Centro de Salud Utrera Sur SevillaSpain Centro de Salud Polígono Sur SevillaSpain Unidad de Trastornos del Movimiento Servicio de Neurología y Neurofisiología ClínicaHospital Universitario Virgen del RocíoSevillaSpain Departamento de Medicina Facultad de MedicinaUniversidad de SevillaSevilleSpain Departamento de Antropología Social Universidad de GranadaSpain Unidad Enfermedades Neuromusculares Servicio de Neurología y Neurofisiología ClínicaHospital Universitario Virgen del RocíoSevillaSpain

In recent years,the number of known disease genes has exponentially grown due to the widespread adoption of cost-effective massive parallel *** identify new disease variants,especially in monogenic disorders,a frequen... 详细信息

关键词： Server filtering massive

Comparison of Apigenin,Quercetin and Kaempferol Accumulation and Total Flavonoid Content in Leaves,Embryogenic Cultures and Cell Suspension Cultures of Parsley(Petroselinum crispum)

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国际实验植物学杂志(英文) 2023年第10期92卷 2807-2823页

作者： Laura Isabel Arias-Rodríguez martha Alicia Rodríguez-Mendiola Carlos Arias-Castro Federico Antonio Gutiérrez Miceli Diana Reséndez Pérez maría Celina Luján Hidalgo Juan JoséVillalobos Maldonado norma alejandra mancilla mar.alli Analytical Laboratory National Technological Institute of MexicoTuxtla Gutierrez CampusTuxtla GutierrezMexico Plant Biotechnology Laboratory Instrumental Analysis LaboratoryPlant Biochemistry LaboratoryNational Technological Institute of MexicoTlajomulco de ZunigaMexico Department of Cellular Biology and Genetics Faculty of Biological SciencesAutonomous University of Nuevo LeonSan Nicolas delos GarzaMexico

In recent years,there has been a growing interest in exploring alternative treatments for bone *** tissue engineering has turned its attention to plant extracts containing osteogenic flavonoids as potential promoters of bone *** our study,we specifically investigated the extract of Petroselinum crispum,a plant known for its abundance of osteogenic flavonoids such as apigenin,quercetin,and *** objective was to compare the total flavonoid content(TFC)and their accumulation in different *** obtained hydrolyzed aqueous extracts from the leaves of parsley plants(grown for 12 weeks in the field),weekly embryogenic cultures,and suspension cell *** TFC,measured in mg quercetin equivalent per gram of dry weight(QE mg/g dw),was found to be 53.81±0.97 for 52 g dw of leaves(1 kg plant fw),31.10±1.52 for 420 g dw of embryogenic cultures,and 11.80±0.76 for 210 g dw of cell ***,only the leaves and embryogenic cultures showed significant accumulation of osteogenic flavonoids,with apigenin levels of 1.8±0.3 and 0.32±0.02 mg/g dw,and kaempferol levels of 1.0±0.18 and 0.2±0.01 mg/g dw,*** findings indicate that embryogenic cultures have the potential to produce up to 40%more apigenin in 12 weeks compared to 1 kg of parsley plant,thanks to their superior biomass reproductive *** results present a promising biotechnological approach for generating extracts enriched with bioactive compounds,which can be further utilized in in vitro osteogenic testing.

关键词： Parsley(Petroselinum crispum)cultures osteogenic flavonoids bone regeneration aqueous extracts

Senescent mesenchymal stem/stromal cells in pre-metastatic bone marrow of untreated advanced breast cancer patients

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Oncology Research 2023年第3期31卷 361-374页

作者： FRANCISCO RAÚL BORZONE marÍA BELÉN GIORELLO LEANDRO marCELO marTINEZ marÍA CECILIA SANmarTIN LEONARDO FELDMAN FEDERICO DIMASE EMILIO BATAGELJ GUSTAVO YANNARELLI norma alejandra CHASSEING Laboratorio de Inmunohematología Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Buenos AiresArgentina Division of Hematology and Medical Oncology Department of MedicineWeill Cornell Medical CollegeNew YorkUSA Laboratorio de Regulación Génica y Células Madre Instituto de Medicina TraslacionalTrasplante y Bioingeniería(IMeTTyB)Universidad Favaloro-CONICETBuenos AiresArgentina Facultad de Ciencias de la Salud Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPB)TandilBuenos AiresArgentina Servicio de Hematología Hospital Militar CentralBuenos AiresArgentina Servicio de Oncología Hospital Militar CentralBuenos AiresArgentina

Breast cancer is the predominant form of carcinoma among women worldwide,with 70%of advanced patients developing bone metastases,with a high mortality *** this sense,the bone marrow(BM)mesenchymal stem/stromal cells(MSCs)are critical for BM/bone homeostasis,and failures in their functionality,transform the BM into a premetastatic niche(PMN).We previously found that BM-MSCs from advanced breast cancer patients(BCPs,infiltrative ductal carcinoma,stage III-B)have an abnormal *** work aims to study some of the metabolic and molecular mechanisms underlying MSCs shift from a normal to an abnormal profile in this group of patients.A comparative analysis was undertaken,which included self-renewal capacity,morphology,proliferation capacity,cell cycle,reactive oxygen species(ROS)levels,and senescence-associatedβ‑galactosidase(SA‑β‑gal)staining of BMderived MSCs isolated from 14 BCPs and 9 healthy volunteers(HVs).Additionally,the expression and activity of the telomerase subunit TERT,as well as telomere length,were *** levels of pluripotency,osteogenic,and osteoclastogenic genes(OCT-4,SOX-2,M-CAM,RUNX-2,BMP-2,CCL-2,M-CSF,and IL-6)were also *** results showed that MSCs from BCPs had reduced,self-renewal and proliferation *** cells also exhibited inhibited cell cycle progression and phenotypic changes,such as an enlarged and flattened ***,there was an increase in ROS and senescence levels and a decrease in the functional capacity of TERT to preserve telomere *** also found an increase in pro-inflammatory/pro-osteoclastogenic gene expression and a decrease in pluripotency gene *** conclude that these changes could be responsible for the abnormal functional profile that MSCs show in this group of patients.

关键词： Mesenchymal stem/stromal cells Senescence Breast cancer Bone marrow Pre-metastatic niche Bone metastasis

The largest dengue outbreak in Argentina and spatial analyses of dengue cases in relation to a control program in a district with sylvan and urban environments

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Asian Pacific Journal of Tropical Medicine 2018年第3期11卷 227-234页

作者： Aníbal E Carbajo alejandra Rubio maría J Viani maría R Colombo Laboratorio de Eoclogía de Enfermedades Transmitidas por Vectores Instituto de Investigación e Ingeniería AmbientalUniversidad Nacional de General San Martín Consejo Nacional de Investigaciones Científicas y Técnicas Secretaria de Política Sanitaria y Desarrollo Humano Municipio de Tigre

Objective: To analyze the largest outbreak of dengue in Argentina in the municipality of Tigre during 2016, through detailed spatial analyses of the occurrence of cases in relation to demographic factors and vector control actions. Methods: Detailed and georreferenced data on dengue cases with laboratory results(NS1 or IgM) were analyzed. The occurrences of imported and autochthonous cases by census tract were modeled using demographic variables(population by age class, proportion of foreigners, proportion with university grade, proportion of males), dwelling variables(number of homes, proportion of dwellings with latrine, number of dwellings, proportion of houses, proportion of flats, proportion of slums) and census tract area as explanatory variables. The probability of occurrence of autochthonous and imported cases was modeled separately. The spatio-temporal occurrence of cases was studied in relation to focal and perifocal control actions(involving education campaigns, removal of Aedes aegypti breeding sites and exhaustive insecticide spraying) to assess the efficiency in stopping autochthonous cases spreading. Results: All autochthonous cases occurred in the urban environment with no sylvan cases. The majority of the imported cases registered came from Paraguay and Northeastern Argentina. The age structure of imported and autochthonous cases did not differ from the age structure of the municipality, while that of the negative cases *** studied spatially, the occurrence of imported cases by census tract was mildly associated with a higher proportion of foreign population and more people at active age, while occurrence of autochthonous cases was not significantly associated with any of the studied *** census tracts with laboratory confirmed results, the models showed higher probability of autochthonous cases related to higher population density and population age structure. The clustering of autochthonous cases was generally mild, with prevailing i

关键词： Aedes aegypti Vector-borne diseases Vector control Dengue epidemic

Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan Gaitán Matías Mastrangelo marcelo Nosetto Pablo E.Villagra Ezequiel Balducci martín Pinazo Roxana P.Eclesia alejandra Von Wallis Sebastián Villarino Francisco Alaggia marina González Polo Silvina Manrique Pablo A.Meglioli Julián Rodríguez-Souilla martín Mónaco Jimena E.Chaves Ariel Medina Ignacio Gasparri Eugenio Alvarez Arnesi maría Paula Barral Axel von Müller Norberto M.Pahr Josefina Uribe Echevarria Pedro Fernández marina Morsucci Dardo López Juan Manuel Cellini Leandro Alvarez Ignacio Barberis Hernán Colomb Ludmila La Manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar Guillermo martínez Pastur Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía No Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección Nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Universidad Nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Administración de Parques Nacionales (APN) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally determined contribution（NDC） presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United Nations Framework Conven-tion on Climate Change（UNFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability due to a lack of information. The objectives of this study were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covari-ates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity Native forest Climate change mitigation Modelling Resilience

Portal Venous Thrombosis and Splenic Hemangioma, Secondary to Acute Pancreatitis: Case Report

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Open Journal of Gastroenterology 2024年第1期14卷 11-17页

作者： Gustavo Adolfo Hernández Valdez Harvey Yair Zamora Veliz Estefany Gilberty Mendoza Verdin Quitzia Mayanim Rentería Fonseca Itzel Velázquez Viniegra Janette alejandra Gamiño Gutierrez Diana Rita Velázquez Jimenez Florencio Favian Andrade Luis Fernando Baez Bustos Jorge Morales Rojas maría Jacqueline martínez Tejeda Graciela Gaddy Robles martínez Juan Antonio Contreras Escamilla Departamento de Medicina Interna ISSSTE Tepic General Hospital APP Tepic Nayarit México General Surgery Department ISSSTE Tepic General Hospital APP Tepic Nayarit México Hospital Civil Fray Antonio Alcalde Guadalajara Jalisco México

We present an unusual case of portal vein thrombosis with a splanchnic hemangioma secondary to acute biliary pancreatitis. We report a 45-year-old patient, who has systemic arterial hypertension in treatment, was admitted for abdominal pain in the epigastrium, with irradiation to the right hypochondrium, accompanied by nausea and vomiting of 10 occasions of bile content, physical examination with pain in the right hypochondrium, Murphy positive. We have laboratory studies with a lipase of 788, so a diagnosis of pancreatitis is made with an etiology to be determined. The laboratories suggestive of acute biliary pancreatitis (lipase 788.71);an imaging study was subsequently performed (ultrasonography) with the result of stone in the common bile duct. A laparoscopy was performed with relative improvement, so he was discharged and returned 20 days after surgery due to abdominal pain of the same intensity in the left hypochondrium. Ending his hospitalization with a splenectomy for splenic hemangioma with portal vein thrombosis.

关键词： Pancreatitis Esplenic Hemangioma Esplenectomy Portal Vein Thrombosis Surgery

Powder metallurgy with space holder for porous titanium implants:A review

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Journal of Materials Science & Technology 2021年第17期76卷 129-149页

作者： alejandra Rodriguez-Contreras Miquel Punset JoséA.Calero Francisco Javier Gil Elisa Ruperez Josémaría Manero Biomaterials Biomechanics and Tissue Engineering Group(BBT)Department of Materials Science and EngineeringUniversitat Politecnica de Catalunya(UPC)Av.Edurad Maristany 1608019BarcelonaSpain Barcelona Research Centre in Multiscale Science and Engineering Technical University of Catalonia(UPC)Av.Eduard Maristany 10-1408019BarcelonaSpain UPC Innovation and Technology Center(CIT-UPC).Technical University of Catalonia(UPC) C.Jordi Girona 3-108034Barcelona.Spain AMES GROUP SA.Carretera Nacional 340 Pol.Ind."Les Fallulles"08620Sant Vicenc dels HortsBarcelonaSpain Bioengineering Institute for Technology Universitat Intemacional de Catalunyac/Josep Trueta s/n08195BarcelonaSpain

One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical *** stress shielding phenomenon provokes bone resorption and the consequent adverse effects on prosthesis ***,it can be inhibited by adapting the stiffness of the implant *** the use of titanium(Ti)porous structures is a great alternative not only to inhibit this effect but also to improve the osteointegration of orthopedic and dental implants,a brief description of the techniques used for their manufacturing and a review of the current commercialized implants produced from porous Ti assemblies are compiled in this *** powder metallurgy(PM)with space holder(SH)is a powerful technology used to produce porous Ti structures,it is here discussed its potential for the fabrication of medical devices from the perspectives of both design and *** most important parameters of the technique such as the size and shape of the initial metallic particles,the SH and binder type of materials,the compaction pressure of the green form,and in the sintering stage,the temperature,atmosphere,and time are reviewed according to the bibliography ***,the importance of the porosity and its types together with the influence of the mentioned parameters in the final porosity and,consequently,in the ultimate mechanical properties of the structure are ***,a few examples of the PM-SH application for the manufacturing of orthopedic implants are presented.

关键词： Powder metallurgy Space holder method Porous titanium structures Medical devices Stress shielding effect Porous materials permeability Interconnected porosity Porous bone substitute materials Open-cell titanium foams Sintering-dissolution technique