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Perfil ecocardiográfico convencional e por strain em pacientes com mucopolissacaridose na Bahia-Brasil. [manuscrito] / Mirela Frederico de Almeida AndradeAndrade, Mirela Frederico de Almeida 15 December 2016 (has links)
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MIRELA FREDERICO DE ALMEIDA ANDRADE.pdf: 2535683 bytes, checksum: ca06f1174b8e7c24e2fc0cea813113d8 (MD5) / INTRODUÇÃO: A mucopolissacaridose é uma doença genética caracterizada por
depósito intralisossômico de glicosaminoglicanos por deficiência enzimática
específica. Afeta diversos órgãos e sistemas do organismo, sendo o
comprometimento cardiovascular frequente e importante causa de morbimortalidade,
caracterizando-se principalmente por lesões valvares esquerdas e hipertrofia do
ventrículo esquerdo. Os sinais e sintomas cardiovasculares são subvalorizados pelo
acometimento concomitante da doença em outros sistemas, como o respiratório e
ósseo. A terapia de reposição enzimática pode ser utilizada em pacientes com essa
enfermidade, nos seus tipos I, II, IV e VI. Os efeitos na doença cardiovascular ainda
estão sendo avaliados. Diante desse panorama, torna-se relevante o conhecimento
da aplicação de novas ferramentas da ecocardiografia convencional e avançada, a
fim de melhorar a assistência cardiológica nessa população. OBJETIVO: Descrever
o perfil ecocardiográfico de pacientes com mucopolissacaridose, por meio da
ecocardiografia convencional e medida de strain dos ventrículos esquerdo e direito,
por meio da técnica speckle-tracking da ecocardiografia bidimensional. MÉTODOS:
Trata-se de um estudo seccional descritivo, de base ambulatorial, sem grupo de
comparação, com pacientes portadores de mucopolissacaridose, acompanhados no
ambulatório de genética do Hospital Universitário Professor Edgard Santos, da
Faculdade de Medicina, da Universidade Federal da Bahia. Os pacientes foram
submetidos à avaliação ecocardiográfica convencional e por strain, no período de
janeiro a junho de 2016. RESULTADOS: Avaliaram-se 16 pacientes com idade
mediana de 14,2 anos (desvio de 5,2 anos), sendo 12 (75%) do sexo masculino. O
tipo mais frequente foi a mucopolissacaridose VI (8 pacientes - 50%), seguido da II
(4 pacientes - 25%), da I (3 pacientes - 18,8%) e apenas um paciente com III (6,2%).
Entre os pacientes com os tipos I, II e VI, apenas um paciente não estava em uso de
terapia de reposição enzimática. A mediana de idade para início da terapia de
reposição enzimática foi de 8 anos (desvio de 4,5 anos). Lesão valvar esquerda foi
encontrada em 15 pacientes (93,3%) com maior prevalência da lesão mitral,
presente em 13 pacientes (81,2%) sendo que todos estes apresentaram
insuficiência valvar. Apenas dois pacientes apresentaram concomitantemente
estenose mitral. Oito (50%) pacientes apresentaram insuficiência aórtica e nenhum
apresentou estenose aórtica. Nenhum paciente apresentou lesão valvar direita.
Hipertrofia do ventrículo esquerdo foi encontrada em dois pacientes, sendo um
paciente com hipertrofia concêntrica e outro com hipertrofia excêntrica, ambos
portadores de mucopolissacaridose II. Doze (75%) pacientes apresentaram
remodelamento concêntrico do ventrículo esquerdo. Todos os pacientes
apresentaram função sistólica do ventrículo esquerdo preservada pelos métodos de
Simpson e Teichholz. Três (18,8%) pacientes tiveram índice de performance
miocárdica do ventrículo esquerdo alterado. Apenas três (18,8%) pacientes
apresentaram disfunção diastólica do ventrículo esquerdo. Um paciente apresentou
redução do fractional area change do ventrículo direito e três (18,8%) tiveram
disfunção diastólica do ventrículo direito. Nenhum paciente apresentou alteração em
tricuspid annular plane systolic excursion ou onda S’ do anel tricuspídeo. Nove
(56,2%) pacientes apresentaram alteração no strain global longitudinal do ventrículo
esquerdo e quatro (25%) apresentaram a mesma alteração do ventrículo direito. O
estudo demonstrou associação positiva entre massa e alteração do índice de
performance miocárdica do ventrículo esquerdo e strain global longitudinal do
ventrículo esquerdo e tempo de início da terapia de reposição enzimática e índice de
performance miocárdica do ventrículo esquerdo e strain global longitudinal ventrículo
esquerdo. CONCLUSÃO: As alterações ecocardiográficas em pacientes com
mucopolissacaridose são frequentes, principalmente as alterações valvares
esquerdas, mudança na geometria ventricular esquerda e disfunção subclínica do
ventrículo esquerdo, diagnosticada pelo strain. As alterações cardíacas são
significativas, fundamentando a importância do acompanhamento cardiológico
regular nessa população. O uso das novas ferramentas da ecocardiografia
convencional e avançada pode aprimorar este acompanhamento, aprimorando,
assim, o seguimento do paciente com mucopolissacaridose.
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EFFECTS OF ADDITION OF LARGE PERCENTAGES OF FLY ASH ON LIQUEFACTION BEHAVIOR OF SAND.Regmi, Gaurav 01 August 2014 (has links)
The liquefaction resistance of a saturated medium sand with varying amount of non-plastic type F fly ash was evaluated by conducting cyclic triaxial tests. The test results were used to evaluate the effect of addition of various percentages of fly ash on the liquefaction resistance of Ottawa sand. The effect of cyclic shear stress and confining pressure on liquefaction resistance of the sand-fly ash mixtures was the main scope of this research. In addition, the Young's Modulus and Damping Ratio for sand-fly ash mixtures were also determined. A comprehensive experimental program was conducted in which 50 stress controlled cyclic triaxial tests were performed on a clean sand, sand containing 25%, 30%, 50% and 70% fly ash at a constant relative density of 50%. The results show that sand containing 25% fly ash has the highest liquefaction resistance under cyclic loading in comparison to clean sand and sand containing 30%, 50% and 70% fly ash. The cyclic resistance goes on decreasing as the fly ash content further increases. The test result also shows that the liquefaction resistance of the clean sand and sand containing 70% fly ii ash is almost same. The test results were also examined in terms of the conceptual framework of Thevanayagam (2000). The effects on liquefaction resistance were also measured in terms of pore water pressure generation and deformation of the sample. As the confining pressure increases, shear stress required to cause initial liquefaction of the sample also increases. Modulus of Elasticity was seen to increase with increase in confining pressure and decrease with increase in axial strain for all cases of sand-fly ash mixtures used in these tests. The damping ratio of the sample increases with the increase in axial strain upto about 1% and then it either decreases or remains constant thereafter. There was no clear correlation of damping ratio with confining pressure.
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Weak Commitment to School, Deviant Peers, and Cyberbullying Victimization-Strain in Adolescent CyberbullyingLee, Charern 01 May 2017 (has links)
Cyberbullying is a relatively new area of research which has developed over the last decade. Although its popularity has taken off recently, more research is needed to discern cyberbullying behavior. This dissertation seeks to address whether weak commitment to school, deviant peers, and cyberbullying victimization-strain variables can explain cyberbullying offending. In addition, it attempts to explain the mediation effects among weak commitment to school, deviant peers, cyberbullying victimization-strain, and cyberbullying offending variables. Using data from two middle schools in the United States, the findings suggest that weak commitment to school, deviant peers, and cyberbullying victimization-strain variables were able to predict cyberbullying offending. The findings also show that deviant peers and cyberbullying victimization-strain mediated, at least partly, the effect of weak commitment to school on cyberbullying offending. Overall, this dissertation indicates weak to moderate support for the commitment to school concept of social bonding theory and moderate to strong support for both the differential association and strain concepts of social learning and general strain theories. Theory and research implications are discussed.
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Digital Laser Speckle Image CorrelationMosayebi, Mahshad 01 May 2017 (has links)
This thesis examines the feasibility of combining Digital Image Correlation (DIC) with laser speckle based methods to form a new hybrid deformation measurement method called Digital Laser Speckle Image Correlation (DilSIC). Consequently, this method does not require any sample preparation and allows for the measurement of displacement of micro structures in addition to large displacements. In this technique, a coherent 30mW-632nm laser beam is expanded with 40X lens and then illuminated on the target surface to produce a fine, homogenous laser speckle pattern. Images were captured before and after deformation due to external load and the whole field displacement and strain were determined by the DIC method. This technique could measure displacement less than 30-μm with high accuracy when a 120mm × 80mm area of the surface was inspected. Up to 10% strain was measured by this technique with high accuracy during the whole range. Eventually the sub-surface crack was located successfully, which is a revolutionary achievement in NDT optical methods. This method was tested in different material, with different roughness. Aluminum sheet and rubber material were used mostly. This method could broaden the capability of displacement measurement and subsurface crack detection in wide range of materials.
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Highly Sensitive in-Plane Strain Mapping Using a Laser Scanning TechniqueJanuary 2014 (has links)
abstract: In this work, a highly sensitive strain sensing technique is developed to realize in-plane strain mapping for microelectronic packages or emerging flexible or foldable devices, where mechanical or thermal strain is a major concern that could affect the performance of the working devices or even lead to the failure of the devices. Therefore strain sensing techniques to create a contour of the strain distribution is desired.
The developed highly sensitive micro-strain sensing technique differs from the existing strain mapping techniques, such as digital image correlation (DIC)/micro-Moiré techniques, in terms of working mechanism, by filling a technology gap that requires high spatial resolution while simultaneously maintaining a large field-of-view. The strain sensing mechanism relies on the scanning of a tightly focused laser beam onto the grating that is on the sample surface to detect the change in the diffracted beam angle as a result of the strain. Gratings are fabricated on the target substrates to serve as strain sensors, which carries the strain information in the form of variations in the grating period. The geometric structure of the optical system inherently ensures the high sensitivity for the strain sensing, where the nanoscale change of the grating period is amplified by almost six orders into a diffraction peak shift on the order of several hundred micrometers. It significantly amplifies the small signal measurements so that the desired sensitivity and accuracy can be achieved.
The important features, such as strain sensitivity and spatial resolution, for the strain sensing technique are investigated to evaluate the technique. The strain sensitivity has been validated by measurements on homogenous materials with well known reference values of CTE (coefficient of thermal expansion). 10 micro-strain has been successfully resolved from the silicon CTE extraction measurements. Furthermore, the spatial resolution has been studied on predefined grating patterns, which are assembled to mimic the uneven strain distribution across the sample surface. A resolvable feature size of 10 µm has been achieved with an incident laser spot size of 50 µm in diameter.
In addition, the strain sensing technique has been applied to a composite sample made of SU8 and silicon, as well as the microelectronic packages for thermal strain mappings. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2014
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Characterization of the Dynamic Strength of Aluminium at Extreme Strain Rates and PressuresJanuary 2017 (has links)
abstract: The study of response of various materials to intense dynamic loading events,
such as shock loading due to high-velocity impacts, is extremely important in a wide
variety of military and industrial applications. Shock loading triggers extreme states,
leading to high pressures and strain rates, and neglecting strength is a typical
approximation under such conditions. However, recent results have shown that strength
effects are larger than expected, so they must be taken into account. Recently,
hydrodynamic instabilities, the most common being the Rayleigh-Taylor (RTI) and
Richtmyer-Meshkov (RMI) instabilities, have been used to infer the dynamic strength of
materials at high pressure conditions. In our experiments and simulations, a novel RMI
approach is used, in which periodic surface perturbations are made on high purity
aluminium target, which was laser ablated to create a rippled shock front. Due to the
slow linear growth rate of RMI, the evolution of the perturbations on the back surface of
the sample as a result of the rippled shock can be measured via Transient Imaging
Displacement Interferometry (TIDI). The velocity history at the free surface was
recorded by spatially resolved laser velocimetry. These measurements were compared
with the results from the simulations, which were implemented using rate independent
and rate dependent material models, to characterize the dynamic strength of the
material. Simulations using the elastic-perfectly plastic model, which is rate
independent, failed to provide a value of dynamic yield strength that would match
experimental measurements of perturbation amplitudes. The Preston-Tonks-Wallace
(PTW) model, which is rate dependent model, worked well for aluminium. This model
was, in turn, used as a reference for calibrating the rate dependent Steinberg-Lund
model and the results from simulations using the calibration models were also compared
to experimental measurements. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2017
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La tension psychique, précurseur des conduites violentes en détention : étude théorico-praxéologique des dynamiques agressives et suicidaires auprès des détenus / Strain as a precursor of violent behaviors during incarcerationChamayou, Jérôme 04 June 2013 (has links)
La violence est un phénomène fréquent dans les prisons. D'après la théorie générale de la tension (Agnew, 1992, 2002), l'agressivité (Blevins et al., 2010) ou le suicide (Zhang et al., 2008) seraient le fruit de tensions éprouvées par les détenus. Notre recherche s'appuie sur le modèle d'Agnew pour créer et tester une échelle standardisée appliquée aux détenus. Les analyses en composantes principales et confirmatoires montrent des résultats satisfaisants, avec des indices de cohérence interne significatifs. Notre échelle est donc une première ébauche pour mesurer la tension en détention. Nos résultats montrent que les comportements agressifs et suicidaires peuvent être prédits de façon significative par la mesure de la tension. Toutefois, la tension en tant que variable indépendante et les stratégies de régulation émotionnelle et/ou de coping comme variables médiatrices ne permettent pas de mettre en évidence des modèles significatifs. Cela signifie que la tension doit être appréhendée comme une variable proximale. De même, nous testons les effets modérateurs des variables personnelles et judiciaires. Nos analyses infirment l'effet modérateur supposé des facteurs personnels et situationnels, même si la dépression et le stress ont un effet significatif. Enfin, nos analyses de médiations modérées ne sont pas significatives, que ce soit pour les comportements agressifs ou suicidaires. Pour conclure, la tension serait la variable la plus proximale pour prédire la violence en prison, alors que la régulation émotionnelle ou les stratégies de coping auraient un effet plus distal. Comme les variables modératrices n'ont pas d'effet significatif, nous proposons de les considérer comme des formes implicites de tension. La théorie de la tension appliquée aux détenus est un modèle prometteur mais récent, qui n'a pas été testé empiriquement. Ainsi, au travers de cette recherche, nous avons essayé de mesurer la tension, afin de tester ce modèle et d'identifier ses limites. / Violence is common and frequent in most prisons. According to the general strain theory (Agnew, 1992, 2002), aggression (Blevins et al., 2010) or suicidality (Zhang et al., 2008) are caused by strains experienced by inmates. Our study intends to rely on Agnew's general strain theory in order to create and test a standardized scale applied to inmates, since no psychometric instrument evaluating Agnew's model exists. Principal component analyses and confirmatory analyses applied to our psychometric data show satisfying results, with significant internal consistency indices. Our scale is thus a first attempt to measure strain for inmates. In a second step, this research aims at understanding the effect of strains on inmates' violent behaviors. Our results show that aggressive and suicidal behaviors can significantly be predicted by the strain measure. The strains due to daily-life in jail have a direct effect (indirect for Agnew) on inmates' externalizing violent outcomes. Then, we test the mediating effects of coping skills and emotion regulation strategies. The model depicted by our analyses is not fully consistent with the general strain theory. Analyses considering strain as an independant variable and coping skills and emotion regulation strategies as mediating variables are not significant. This implies that strain measure could be seen as a proximal variable. This conclusion does not totally support Agnew's model, which considers strain as a distal variable. In a next step, we test the moderating effects of personal and judicial variables. Our analyzes invalidate the supposed moderating effect of such factors, even if depression and stress are significant moderating variables. Finally, our moderated mediating analyses are not significant, whether on aggressive or suicidal behaviors. As a conclusion, according to our results, strain would be a proximal variable to predict violence in prison, whereas emotion regulation or coping strategies would be more distal. As the moderating variables are not significant, we suggest to consider them as indirect forms of strains. The general strain theory, especially applied to inmates, is a promising but recent model which has not been empirically tested. Therefore, through this research, we tried to measure strain, in order to test this model and identify its limits.
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Uma abordagem da vida em fadiga em barra estabilizadora automotiva considerando defeito superficial fisicamente pequenoCOLOSIO, MARCO A. 09 October 2014 (has links)
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09601.pdf: 14581150 bytes, checksum: 039930ea0467d8cb98d0f2a68ecb3072 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Extensometria : avaliação de implantes de sextavado externo posicionados na configuração linear e compensada (offset), sob carregamento axial /Kojima, Alberto Noriyuki. January 2008 (has links)
Orientador: Renato Sussumu Nishioka / Banca: Wirley Gonçalves Assunção / Banca: Alysson Noriyuki Kajishima Konno / Banca: Eduardo Shigueyuki Uemura / Banca: Osvaldo Daniel Andreatta Filho / Resumo: O objetivo deste estudo foi avaliar, por meio da extensometria, a distribuição de tensões ao redor de implantes em função dos diferentes locais para carregamento, tipo de coifa (plástica ou usinada) e configuração (linear e compensada). Para tanto, em um bloco de poliuretano, foram posicionados paralelos entre si e com uma configuração linear, implantes auto-rosqueáveis de hexágono externo, com dimensões de 3,75 X 13mm, a uma distancia de 7mm, de centro a centro. Em um outro bloco a fixação do meio foi deslocada em 2mm para gerar uma configuração compensada (offset). Pilares protéticos Micro-unit, com 3mm de cinta foram instalados sobre as fixações. Com duas matrizes em aço inoxidável foram confeccionados 10 enceramentos para cada bloco, distribuídos da seguinte forma: 5 para coifa plástica e 5 para coifas usinadas (n=5). A seguir esses padrões foram fundidos com uma liga de Co-Cr. Quatro extensômetros (strain gauges) foram colados na superfície superior de cada bloco tangenciando a plataforma de cada fixação. Um carregamento de 30kg durante 10s foi feito em cinco posições (A, B, C, D, E), sendo repetido três vezes para aquisição dos dados (em με) pela aparelho condicionador de sinais. Os dados obtidos foram submetidos a análise de variância (ANOVA) e teste de Tukey (p<0,05). Como conclusão da análise dos resultados obtidos pudemos observar que não houve diferença na utilização de coifas plásticas e usinadas, que não houve diferença entre as configurações linear e compensada; havendo diferença estatisticamente significante para os locais de carregamento / Abstract: The aim of this study was to evaluate, using strain gauge, the load distribution surround the implants according differents loading sites, coping types (plastic and machined) and configuration (linear and offset). In one polyurethane block, three cylindrical implants with external hexagon (3.75mm x 13mm) were fixed parallel with 7mm between their centers in a linear configuration. In another block the midle implant was positioned in a 2mm offset. Micro-units abutments with 3mm of metallic neck were fixed. With two metallics matrix, it was manufactured 10 wax patterns for each block, distributed in the following form: 5 for plastic copings and 5 for machined copings (n=5). After, patterns were casted in cobalt-chromium alloy. Four strain gauges were positioned on the upper surface of each polyurethane model around the implants. An axial load of 30kg within 10 seconds in five positions (A, B, C, D, E), with three repetead measurements for data aquisition (in με) by the multichanel bridge machine. The datas were submitted to ANOVA and Tukey test (p<0.05). Such as conclusion from the obtained data treatment: there was no difference between the plastic and machined copings, there was no difference between the linear and offset configuration; there was statiscal significance only with the differents loading sites. / Doutor
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Avaliação ecocardiográfica da função do ventrículo direito de cães da raça Boxer com cardiomiopatia arritmogênica do ventrículo direito: estudo caso-controle / Echocardiographic assessment of right ventricular function in Boxer dogs with arrhythmogenic right ventricular cardiomyopathy: case-control studyFenerich, Michelli 12 April 2018 (has links)
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Previous issue date: 2018-04-12 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A cardiomiopatia arritmogênica do ventrículo direito (CAVD) é uma doença de origem genética, muito prevalente em cães da raça Boxer. Histologicamente ocorre atrofia dos cardiomiócitos do ventrículo direito (VD) e consequente infiltração fibroadiposa, levando ao aparecimento de arritmias ventriculares. Mesmo sendo as alterações miocárdicas microscópicas em sua maioria, estudos recentes têm identificado disfunção contrátil do ventrículo direito, mesmo em estágios iniciais da doença em humanos, tanto por técnicas convencionais de ecocardiografia quanto por técnicas mais avançadas, como no caso do speckle tracking. Por isso, o objetivo deste estudo foi avaliar se há disfunção miocárdica de VD detectável pela ecocardiografia convencional e pela técnica de speckle tracking bidimensional em cães da raça Boxer portadores da CAVD. Para tanto, utilizou-se cães da raça Boxer com idade superior a quatro anos, distribuídos em dois grupos de acordo com o resultado da avaliação Holter (GC: < 50 EVs/24h, n=11 e GD: > 100 EVs/24h, n=11). Os animais foram submetidos a ecocardiografia e avaliou-se diâmetro e comprimento interno do VD em sístole e diástole, encurtamento fracional da área do VD (FAC), excursão sistólica do plano anular da tricúspide (TAPSE), velocidade miocárdica sistólica do ânulo lateral da tricúspide derivada do Doppler tecidual (S’) e deformação (strain) e taxa de deformação (strain rate) longitudinal global da parede livre do VD, derivados da análise por speckle tracking. As variáveis foram comparadas entre os grupos pelo teste t de Student e de Mann-Whitney e a correlação entre variáveis ecocardiográficas convencionais e de speckle tracking e o número e severidade das arritmias pelo teste de correlação de Pearson, com nível de significância de 5%. Os grupos não foram estatisticamente diferentes e não houve correlação entre os dados. Os resultados da pesquisa demonstraram que a ecocardiografia, tanto na avaliação do VD por índices sistólicos convencionais quanto por aqueles derivados da técnica de speckle tracking não foram capazes de detectar disfunção miocárdica do VD em Boxers portadores de CAVD. / Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disease with a high prevalence in Boxer dogs. Histologically, right ventricle (RV) cardiomyocytes’ atrophy occurs, and thus fibrofatty infiltration, triggering ventricular arrhythmias. Although the myocardial changes are mostly microscopic, recent studies in human beings have identified right ventricular systolic dysfunction even in the early stages of ARVC, both by conventional echocardiographic techniques and advanced methods, such as speckle tracking. Therefore, the aim of this study was to investigate if RV myocardial dysfunction is present in Boxers affected by ARVC, evaluated by conventional echocardiography and bidimensional speckle tracking technique. For this purpose, Boxers older than four years were recruited, and based on 24-hour Holter recording were divided in groups: GC:< 50 VPC/24h (n=11), or GD: > 100 VPC/24h (n=11). The following echocardiographic parameters were analyzed: RV internal dimension during systole and diastole; RV fractional area change (FAC); tricuspid annular plane systolic excursion (TAPSE); myocardial systolic velocity of lateral tricuspid annulus (S’), and global longitudinal strain and strain rate. Groups were compared by Student’ t-test or Mann-Whitney test according distribution, and correlation between conventional and speckle tracking echocardiographic variables, as well as number and severity of the ventricular arrhythmias were accomplished by the Pearson test, assuming a level of significance at 5%. Groups were considered similar, and there was no correlation among the evaluated parameters. Our findings suggesting that the echocardiographic evaluation of RV, either by conventional and speckle tracking techniques, were not able to detect systolic myocardial dysfunction in Boxers affected by ARVC. / FAPESP: 16/14800-7
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