Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
New Phytol ; 242(2): 700-716, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382573

RESUMO

Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis. We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants. The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica. These results alter our understanding of the geographic origin of orchids, previously proposed as Australian, and pinpoint Central America as a region of recent, explosive speciation.


Assuntos
Clima , Orchidaceae , Austrália , Filogenia , Filogeografia , Orchidaceae/genética
2.
PhytoKeys ; 229: 21-46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457384

RESUMO

A checklist of Orchidaceae from Caquetá, Colombia is presented here. We recorded 98 genera and 418 species, exceeding a previous inventory by 276 species. The checklist is conservative in the number of genera and species by including only taxa that were fully and reliably identified and that are either linked to a corresponding herbarium voucher, a living collection specimen or a photo taken in the field and published in iNaturalist by one of the authors or a collaborator. The documented species diversity in the region could dramatically increase in the next few years with additional collecting efforts in the eastern slopes of the Andes nested in Caquetá. About 9% (418/4600) of all Orchidaceae species recorded for Colombia are reported for this area, showing the important contribution to orchid diversity of Andean-Amazonian foothills of Caquetá.

3.
Am J Bot ; 110(2): e16117, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36480380

RESUMO

PREMISE: Recent phylogenetic studies of the Araceae have confirmed the position of the duckweeds nested within the aroids, and the monophyly of a clade containing all the unisexual flowered aroids plus the bisexual-flowered Calla palustris. The main objective of the present study was to better resolve the deep phylogenetic relationships among the main lineages within the family, particularly the relationships between the eight currently recognized subfamilies. We also aimed to confirm the phylogenetic position of the enigmatic genus Calla in relation to the long-debated evolutionary transition between bisexual and unisexual flowers in the family. METHODS: Nuclear DNA sequence data were generated for 128 species across 111 genera (78%) of Araceae using target sequence capture and the Angiosperms 353 universal probe set. RESULTS: The phylogenomic data confirmed the monophyly of the eight Araceae subfamilies, but the phylogenetic position of subfamily Lasioideae remains uncertain. The genus Calla is included in subfamily Aroideae, which has also been expanded to include Zamioculcadoideae. The tribe Aglaonemateae is newly defined to include the genera Aglaonema and Boycea. CONCLUSIONS: Our results strongly suggest that new research on African genera (Callopsis, Nephthytis, and Anubias) and Calla will be important for understanding the early evolution of the Aroideae. Also of particular interest are the phylogenetic positions of the isolated genera Montrichardia, Zantedeschia, and Anchomanes, which remain only moderately supported here.


Assuntos
Araceae , Magnoliopsida , Filogenia , Araceae/genética , Magnoliopsida/genética , Análise de Sequência de DNA
4.
Arq. bras. cardiol ; 118(4): 745-753, Apr. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1374339

RESUMO

Resumo Fundamento A pandemia de COVID-19 interferiu na prestação de atendimento a doenças cardiovasculares na América Latina. No entanto, o efeito da pandemia nos volumes de procedimentos cardíacos diagnósticos ainda não foi quantificado. Objetivo Avaliar (1) o impacto de COVID-19 nos volumes de diagnóstico cardíaco na América Latina e (2) determinar sua relação com a incidência de casos de COVID-19 e as medidas de distanciamento social. Métodos A International Atomic Energy Agency realizou uma pesquisa mundial avaliando mudanças nos volumes diagnósticos cardíacos decorrentes da COVID-19. Foram obtidos os volumes diagnósticos cardíacos dos locais participantes para março e abril de 2020 e comparados com março de 2019. Foram coletados dados de distanciamento social a partir dos Relatórios de mobilidade da comunidade de Google e a incidência de COVID-19 por país a partir de Our World in Data. Resultados Foram realizadas pesquisas em 194 centros que realizam procedimentos diagnósticos cardíacos, em 19 países da América Latina. Em comparação com o mês de março de 2019, os volumes dos procedimentos diagnósticos cardíacos diminuíram 36% em março de 2020 e 82% em abril de 2020.As maiores reduções ocorreram em relação aos testes de estresse ecocardiográfico (91%), testes ergométricos de esteira (88%) e escore de cálcio por tomografia computadorizada (87%), com pequenas variações entre as sub-regiões da América Latina. As mudanças em padrões de distanciamento social (p < 0,001) estavam mais fortemente associadas com a redução do volume do que a incidência de COVID-19 (p = 0,003). Conclusões A COVID-19 foi associada a uma redução significativa de procedimentos diagnósticos cardíacos na América Latina, a qual foi mais relacionada ao distanciamento social do que ao aumento da incidência da COVID-19. São necessários melhor equilíbrio e timing de medidas de distanciamento social e planejamento para manter o acesso ao atendimento médico durante um surto pandêmico, especialmente em regiões com alta mortalidade cardiovascular.


Abstract Background The COVID-19 pandemic has disrupted the delivery of care for cardiovascular diseases in Latin America. However, the effect of the pandemic on the cardiac diagnostic procedure volumes has not been quantified. Objective To assess (1) the impact of COVID-19 on cardiac diagnostic volumes in Latin America and (2) determine its relationship with COVID-19 case incidence and social distancing measures. Methods The International Atomic Energy Agency conducted a worldwide survey assessing changes in cardiac diagnostic volumes resulting from COVID-19. Cardiac diagnostic volumes were obtained from participating sites for March and April 2020 and compared to March 2019. Social distancing data were collected from Google COVID-19 community mobility reports and COVID-19 incidence per country from the Our World in Data. Results Surveys were conducted in 194 centers performing cardiac diagnostic procedures, in 19 countries in Latin America. Procedure volumes decreased 36% from March 2019 to March 2020, and 82% from March 2019 to April 2020. The greatest decreases occurred in echocardiogram stress tests (91%), exercise treadmill tests (88%), and computed tomography calcium scores (87%), with slight variations between sub-regions of Latin America. Changes in social distancing patterns (p < 0.001) were more strongly associated with volume reduction than COVID-19 incidence (p = 0.003). Conclusions COVID-19 was associated with a significant reduction in cardiac diagnostic procedures in Latin America, which was more related to social distancing than to the COVID-19 incidence. Better balance and timing of social distancing measures and planning to maintain access to medical care is warranted during a pandemic surge, especially in regions with high cardiovascular mortality.

5.
Arq Bras Cardiol ; 118(4): 745-753, 2022 04.
Artigo em Inglês, Português | MEDLINE | ID: mdl-35137793

RESUMO

BACKGROUND: The COVID-19 pandemic has disrupted the delivery of care for cardiovascular diseases in Latin America. However, the effect of the pandemic on the cardiac diagnostic procedure volumes has not been quantified. OBJECTIVE: To assess (1) the impact of COVID-19 on cardiac diagnostic volumes in Latin America and (2) determine its relationship with COVID-19 case incidence and social distancing measures. METHODS: The International Atomic Energy Agency conducted a worldwide survey assessing changes in cardiac diagnostic volumes resulting from COVID-19. Cardiac diagnostic volumes were obtained from participating sites for March and April 2020 and compared to March 2019. Social distancing data were collected from Google COVID-19 community mobility reports and COVID-19 incidence per country from the Our World in Data. RESULTS: Surveys were conducted in 194 centers performing cardiac diagnostic procedures, in 19 countries in Latin America. Procedure volumes decreased 36% from March 2019 to March 2020, and 82% from March 2019 to April 2020. The greatest decreases occurred in echocardiogram stress tests (91%), exercise treadmill tests (88%), and computed tomography calcium scores (87%), with slight variations between sub-regions of Latin America. Changes in social distancing patterns (p < 0.001) were more strongly associated with volume reduction than COVID-19 incidence (p = 0.003). CONCLUSIONS: COVID-19 was associated with a significant reduction in cardiac diagnostic procedures in Latin America, which was more related to social distancing than to the COVID-19 incidence. Better balance and timing of social distancing measures and planning to maintain access to medical care is warranted during a pandemic surge, especially in regions with high cardiovascular mortality.


FUNDAMENTO: A pandemia de COVID-19 interferiu na prestação de atendimento a doenças cardiovasculares na América Latina. No entanto, o efeito da pandemia nos volumes de procedimentos cardíacos diagnósticos ainda não foi quantificado. OBJETIVO: Avaliar (1) o impacto de COVID-19 nos volumes de diagnóstico cardíaco na América Latina e (2) determinar sua relação com a incidência de casos de COVID-19 e as medidas de distanciamento social. MÉTODOS: A International Atomic Energy Agency realizou uma pesquisa mundial avaliando mudanças nos volumes diagnósticos cardíacos decorrentes da COVID-19. Foram obtidos os volumes diagnósticos cardíacos dos locais participantes para março e abril de 2020 e comparados com março de 2019. Foram coletados dados de distanciamento social a partir dos Relatórios de mobilidade da comunidade de Google e a incidência de COVID-19 por país a partir de Our World in Data. RESULTADOS: Foram realizadas pesquisas em 194 centros que realizam procedimentos diagnósticos cardíacos, em 19 países da América Latina. Em comparação com o mês de março de 2019, os volumes dos procedimentos diagnósticos cardíacos diminuíram 36% em março de 2020 e 82% em abril de 2020.As maiores reduções ocorreram em relação aos testes de estresse ecocardiográfico (91%), testes ergométricos de esteira (88%) e escore de cálcio por tomografia computadorizada (87%), com pequenas variações entre as sub-regiões da América Latina. As mudanças em padrões de distanciamento social (p < 0,001) estavam mais fortemente associadas com a redução do volume do que a incidência de COVID-19 (p = 0,003). CONCLUSÕES: A COVID-19 foi associada a uma redução significativa de procedimentos diagnósticos cardíacos na América Latina, a qual foi mais relacionada ao distanciamento social do que ao aumento da incidência da COVID-19. São necessários melhor equilíbrio e timing de medidas de distanciamento social e planejamento para manter o acesso ao atendimento médico durante um surto pandêmico, especialmente em regiões com alta mortalidade cardiovascular.


Assuntos
COVID-19 , Cardiopatias , COVID-19/diagnóstico , COVID-19/epidemiologia , Cardiopatias/epidemiologia , Humanos , América Latina/epidemiologia , Pandemias , Inquéritos e Questionários
6.
PhytoKeys ; 162: 71-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117071

RESUMO

A new species of the genus Besleria (Gesneriaceae), endemic to the department of Cauca, Colombia, is described and illustrated here. The new species, Besleria santaclarensis Clavijo & Sánchez-Taborda, was discovered in the Regional Protective Forest Reserve "Serranía El Pinche", Cordillera Occidental of the Colombian Andes. B. santaclarensis is distinguished by the epedunculate inflorescences, usually in the leafless axils near the base, with up to eight orange flowers, and by the magenta calyx that covers 2/3 of the corolla.

7.
Planta ; 251(3): 72, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32112137

RESUMO

MAIN CONCLUSION: This study provides broad insight into the chloroplast genomes of the subfamily Monsteroideae. The identified polymorphic regions may be suitable for designing unique and robust molecular markers for phylogenetic inference. Monsteroideae is the third largest subfamily (comprises 369 species) and one of the early diverging lineages of the monocot plant family Araceae. The phylogeny of this important subfamily is not well resolved at the species level due to scarcity of genomic resources and suitable molecular markers. Here, we report annotated chloroplast genome sequences of four Monsteroideae species: Spathiphyllum patulinervum, Stenospermation multiovulatum, Monstera adansonii, and Rhaphidophora amplissima. The quadripartite chloroplast genomes (size range 163,335-164,751 bp) consist of a pair of inverted repeats (25,270-25,931 bp), separating a small single copy region (21,448-22,346 bp) from a large single copy region (89,714-91,841 bp). The genomes contain 114 unique genes, including four rRNA genes, 80 protein-coding genes, and 30 tRNA genes. Gene features, amino acid frequencies, codon usage, GC contents, oligonucleotide repeats, and inverted repeats dynamics exhibit similarities among the four genomes. Higher rate of synonymous substitutions was observed as compared to non-synonymous substitutions in 76 protein-coding genes. Positive selection was observed in seven protein-coding genes, including psbK, ndhK, ndhD, rbcL, accD, rps8, and ycf2. Our included species of Araceae showed the monophyly in Monsteroideae and other subfamilies. We report 30 suitable polymorphic regions. The polymorphic regions identified here might be suitable for designing unique and robust markers for inferring the phylogeny and phylogeography among closely related species within the genus Spathiphyllum and among distantly related species within the subfamily Monsteroideae. The chloroplast genomes presented here are a valuable contribution towards understanding the molecular evolutionary dynamics in the family Araceae.


Assuntos
Araceae/classificação , Araceae/genética , Evolução Molecular , Genes de Plantas/genética , Genoma de Cloroplastos/genética , Filogenia , Composição de Bases , Sequência de Bases , Cloroplastos/genética , Uso do Códon , DNA de Plantas , Genes de RNAr , Componentes Genômicos , Tamanho do Genoma , Anotação de Sequência Molecular , Fases de Leitura Aberta , Folhas de Planta/genética , Proteínas de Plantas/genética , Polimorfismo Genético , RNA de Transferência/genética
8.
Genomics ; 112(3): 2349-2360, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31945463

RESUMO

Aroideae is the largest and most diverse subfamily of the plant family Araceae. Despite its agricultural and horticultural importance, the genomic resources are sparse for this subfamily. Here, we report de novo assembled and fully annotated chloroplast genomes of 13 Aroideae species. The quadripartite chloroplast genomes (size range of 158,177-170,037 bp) are comprised of a large single copy (LSC; 75,594-94,702 bp), a small single copy (SSC; 12,903-23,981 bp) and a pair of inverted repeats (IRs; 25,266-34,840 bp). Notable gene rearrangements and IRs contraction / expansions were found for Anchomanes hookeri and Zantedeschia aethiopica. Codon usage, amino acid frequencies, oligonucleotide repeats, GC contents, and gene features revealed similarities among the 13 species. The number of oligonucleotide repeats was uncorrelated with genome size or phylogenetic position of the species. Phylogenetic analyses corroborated the monophyly of Aroideae but were unable to resolve the positions of Calla and Schismatoglottis.


Assuntos
Araceae/genética , Evolução Molecular , Genoma de Cloroplastos , Aminoácidos/análise , Araceae/classificação , Uso do Códon , Genes de Cloroplastos , Sequências Repetidas Invertidas , Oligonucleotídeos/química , Filogenia
9.
PhytoKeys ; 135: 21-34, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736629

RESUMO

Two new species of Chlorospatha (section Orientales) from the western slope of the Cordillera Occidental in the departments of Valle del Cauca and Choco (Colombia) are described here. The new species represent the first records of section Orientales for Colombia, which was previously known only from the eastern Andes in Ecuador. The two new species are similar to C. longipoda, C. hannoniae and C. boosii. Chlorospatha minima sp. nov. is differentiated by its small overall size (less than 30 cm tall), blade strongly inequilateral with smooth adaxial surface, and spadix less than 2.2 cm long. Chlorospatha silverstonei sp. nov. is differentiated by its large overall size (30-60 cm tall), 1-3 leaves per plant, and quilted adaxial blade surface.

10.
Am J Bot ; 105(11): 1888-1910, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30368769

RESUMO

PREMISE OF THE STUDY: We present the first plastome phylogeny encompassing all 77 monocot families, estimate branch support, and infer monocot-wide divergence times and rates of species diversification. METHODS: We conducted maximum likelihood analyses of phylogeny and BAMM studies of diversification rates based on 77 plastid genes across 545 monocots and 22 outgroups. We quantified how branch support and ascertainment vary with gene number, branch length, and branch depth. KEY RESULTS: Phylogenomic analyses shift the placement of 16 families in relation to earlier studies based on four plastid genes, add seven families, date the divergence between monocots and eudicots+Ceratophyllum at 136 Mya, successfully place all mycoheterotrophic taxa examined, and support recognizing Taccaceae and Thismiaceae as separate families and Arecales and Dasypogonales as separate orders. Only 45% of interfamilial divergences occurred after the Cretaceous. Net species diversification underwent four large-scale accelerations in PACMAD-BOP Poaceae, Asparagales sister to Doryanthaceae, Orchidoideae-Epidendroideae, and Araceae sister to Lemnoideae, each associated with specific ecological/morphological shifts. Branch ascertainment and support across monocots increase with gene number and branch length, and decrease with relative branch depth. Analysis of entire plastomes in Zingiberales quantifies the importance of non-coding regions in identifying and supporting short, deep branches. CONCLUSIONS: We provide the first resolved, well-supported monocot phylogeny and timeline spanning all families, and quantify the significant contribution of plastome-scale data to resolving short, deep branches. We outline a new functional model for the evolution of monocots and their diagnostic morphological traits from submersed aquatic ancestors, supported by convergent evolution of many of these traits in aquatic Hydatellaceae (Nymphaeales).


Assuntos
Especiação Genética , Genomas de Plastídeos , Magnoliopsida/genética , Filogenia , DNA Intergênico , Zingiberales/genética
12.
Cladistics ; 32(6): 581-605, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34727673

RESUMO

We present the first phylogenomic analysis of relationships among all ten families of Liliales, based on 75 plastid genes from 35 species in 29 genera, and 97 additional plastomes stratified across angiosperm lineages. We used a supermatrix approach to extend our analysis to 58 of 64 genera of Liliales, and calibrated the resulting phylogeny against 17 fossil dates to produce a new timeline for monocot evolution. Liliales diverged from other monocots 124 Mya and began splitting into separate families 113 Mya. Our data support an Australian origin for Liliales, with close relationships between three pairs of lineages (Corsiaceae/Campynemataceae, Philesiaceae/Ripogonaceae, tribes Alstroemerieae/Luzuriageae) in South America and Australia or New Zealand reflecting teleconnections of these areas via Antarctica. Long-distance dispersal (LDD) across the Pacific and Tasman Sea led to re-invasion of New Zealand by two lineages (Luzuriaga, Ripogonum); LDD allowed Campynemanthe to colonize New Caledonia after its submergence until 37 Mya. LDD permitted Colchicaceae to invade East Asia and Africa from Australia, and re-invade Africa from Australia. Periodic desert greening permitted Gloriosa and Iphigenia to colonize Southeast Asia overland from Africa, and Androcymbium-Colchicum to invade the Mediterranean from South Africa. Melanthiaceae and Liliaceae crossed the Bering land-bridge several times from the Miocene to the Pleistocene.

13.
Proc Biol Sci ; 282(1814)2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26311671

RESUMO

Orchids are the most diverse family of angiosperms, with over 25 000 species,more than mammals, birds and reptiles combined. Tests of hypotheses to account for such diversity have been stymied by the lack of a fully resolved broad-scale phylogeny. Here,we provide such a phylogeny, based on 75 chloroplast genes for 39 species representing all orchid subfamilies and 16 of 17 tribes, time-calibrated against 17 angiosperm fossils. Asupermatrix analysis places an additional 144 species based on three plastid genes. Orchids appear to have arisen roughly 112 million years ago (Mya); the subfamilies Orchidoideae and Epidendroideae diverged from each other at the end of the Cretaceous; and the eight tribes and three previously unplaced subtribes of the upper epidendroids diverged rapidly from each other between 37.9 and 30.8 Mya. Orchids appear to have undergone one significant acceleration of net species diversification in the orchidoids, and two accelerations and one deceleration in the upper epidendroids. Consistent with theory, such accelerations were correlated with the evolution of pollinia, the epiphytic habit, CAM photosynthesis, tropical distribution (especially in extensive cordilleras),and pollination via Lepidoptera or euglossine bees. Deceit pollination appears to have elevated the number of orchid species by one-half but not via acceleration of the rate of net diversification. The highest rate of net species diversification within the orchids (0.382 sp sp(-1) My(-1)) is 6.8 times that at the Asparagales crown.


Assuntos
Evolução Biológica , Orchidaceae/classificação , Orchidaceae/genética , Filogenia , Animais , Abelhas , Cloroplastos/genética , Enganação , Genoma de Planta , Lepidópteros , Fotossíntese , Polinização/genética , Fatores de Tempo
14.
Ear Nose Throat J ; 93(8): E22-4, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25181670

RESUMO

Paragangliomas are uncommon tumors that arise from the parasympathetic neuroectodermal ganglionic cells and have been described in numerous anatomic locations, most commonly in the abdomen. Head and neck paragangliomas are classified into carotid body (most common), vagal, and jugulotympanic types. Computed tomography is the initial imaging modality of choice for the preoperative assessment of the extent of paragangliomas. Magnetic resonance imaging and selective angiography provide more detail of the surrounding tissues and vasculature. Surgical resection is the treatment of choice.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Paraganglioma/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
15.
Rev. bras. ecocardiogr. imagem cardiovasc ; 26(1): 52-55, jan.-mar.2013. ilus
Artigo em Português | LILACS | ID: lil-663442

RESUMO

Apresentamos um relato de caso no qual o diagnóstico de ausência congênita do pericárdio (ACP) foi, inicialmente, suspeito na análise ecocardiográfica bidimensional, devido à presença do ápice posterior deslocado na janela das quatro câmaras na direção da linha axilar média. Posteriormente, o diagnóstico foi confirmado por um raio-x do tórax, ressonância magnética e tomografia computadorizada do tórax.


We report a case in which the diagnosis of congenital absence of the pericardium (ACP) was initially suspected in two-dimensional echocardiographic analysis due to the presence of the apex later moved in the window of the four chambers in the direction of the midaxillary line. Subsequently, the diagnosis was confirmed by a chest x-ray, magnetic resonance imaging and computed tomography.


Assuntos
Humanos , Masculino , Adulto , Cardiopatias Congênitas/complicações , Ecocardiografia/métodos , Pericárdio , Taquicardia/complicações
16.
Rev. colomb. radiol ; 17(1): 1868-1887, mar. 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-521537

RESUMO

La cardiotomografía computada (CTC) es una modalidad diagnóstica en constante evolución que incluye un número de exámenes que permiten evaluar la anatomía y la patología de los grandes vasos del tórax, del corazón y del pericardio. En la actualidad, con los equipos de tomografía computarizada multicorte (multidetectores) de última generación —con una mayor cantidad de filas de detectores, colimación más fina, mayor rapidez, habilidad de realizar estudios acoplados al trazo electrocardiográfico y posibilidad de modulación de la dosis de radiación— se puede realizar de una manera confiable, precisa y rápida la evaluación de las arterias coronarias, de la placa arteriosclerótica y de la función cardiaca. Una adecuada selección y preparación de los pacientes son requisitos fundamentales para obtener estudios diagnósticos de la más alta calidad.


Assuntos
Humanos , Vasos Coronários , Coração , Pericárdio , Tomografia
17.
Rev. colomb. radiol ; 13(3): 1179-1188, sept. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-346362

RESUMO

Este artículo de revisión describe la Tomografía Helicoidal sin contraste del árbol urinario o Uro-TAC, analiza susventajas y desventajas y expone el protocolo para su realización. El Uro - TAC Es una modalidad diagnóstica rápida que no requiere preparación antes del examen ni la administración de contraste oral o intravenoso, evitando riesgos y costos inherentes a los mismos. Es efectivo en la identificación de los cálculos ureterales. independiente de su composición proporcionando, información volumétrica, lo que evita artificios de volumen parcial. Es una técnica independiente del operador y no se afecta por la constitución del paciente. El examen en sí tiene una curva de aprendizaje breve , después de la cual, la interpretación de las imágenes es rápida y sencilla. Permite además el diagnóstico de otras patologías diferentes a las litiasis, que pueden ser las causantes de dolor abdominal. Entre sus desventajas se exponen y analizan la dosis de radiación sus costos y la valoración limitada del grado de obstrucción ureteral


Assuntos
Cálculos Urinários/diagnóstico , Tomografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...