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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Prédiction de la fracture osseuse du col du fémur : modélisation par éléments finis basée sur la mécanique d’endommagement et validation expérimentale / prediction of proximal femur fracture : finite element modeling based on mechanical damage and experimental validation

Bettamer, Awad 22 November 2013 (has links)
Les fractures causées par l'ostéoporose de l’extrémité supérieure du fémur sont devenues un problème majeur de santé publique. Par conséquent, ce sujet devient un axe de recherche de plus en plus important pour les cliniciens et les chercheurs biomédicaux. Le but de cette étude est de développer une nouvelle approche pour prédire la fracture du col du fémur. Cette étude propose de développer et valider des modèles par éléments finis (EF) en 2D et 3D, basés sur le concept de l’endommagement mécanique des milieux continus, permettant de simuler la fracture de la partie proximale du fémur en tenant compte de l’initiation progressive de fissures et leur progression. Deux configurations ont été utilisées: appui monopodal et chute. L’ensemble des lois de comportements quasi fragile couplées à une loi d’endommagement sont implémentées en langage FORTRAN dans ABAQUS/Standard (sous-programme de type UMAT). La densité minérale osseuse (BMD) a été mesurée par l’absorptiométrie à rayon X en double énergie DXA pour la région d'intérêt. Les modèles ont été développés dans deux variantes (l’une isotrope et l’autre orthotrope) puis validés avec des résultats expérimentaux obtenus sur des essais en appui monopodale réalisés sur des fémurs humain. Durant ces essais, des mesures optiques basées sur la méthode de corrélation d'images numériques (DIC) ont été réalisées afin d’acquérir les différents champs de déplacement et de déformation. Le modèle numérique 3D a réussi à prédire l’ensemble de la courbe force-déplacement ainsi que l'emplacement et l'amorce de la rupture des fémurs. Par ailleurs, Malgré sa robustesse, la variante 3D du modèle numérique reste difficilement exploitable dans l’état pour réaliser un diagnostic préventif dans des délais acceptables pour des cliniciens, car très consommatrice en temps de calcul. Pour pallier à cela, le modèle simplifié en 2D a été préliminairement validé sous les mêmes conditions aux limites et les résultats ont montré une bonne corrélation avec l’expérience. Ces travaux ont souligné le potentiel de la modélisation par éléments finis basée sur l’endommagement quasi-fragile à devenir un outil complémentaire de prédiction du risque de la fracture osseuse. / Femoral fractures caused by the osteoporosis become major problem of public health, and therefore, this subject becomes an increasingly important goal for both clinicians and biomedical researchers. The purpose of this study is to develop a new coupled approach to predict the fracture of neck femoral. The current study proposes a validated 2D and 3D finite element (FE) models based on continuum damage mechanics in order to simulate human proximal femur fracture considering the progressive cracks initiation and propagation. These models are applied and validated under single limb stance and sideways fall configuration. Quasi brittle behavior laws coupled to damage are implemented in FORTRAN and fed into ABAQUS/Standard codes to describe the constitutive behavior (subroutine UMAT). Bone mineral density (BMD) is measured using dual energy X-ray absorptiometry (DXA) for the region of interest. The models have been developed within two variants (one isotropic, the other anisotropic) and validated with experimental results of tests performed on human femur samples under single limb stance configuration. During these tests, optical measurements based on the method of digital image correlation (DIC) were conducted to acquire the various fields of displacement and deformation. To calculate the fracture risk of the femoral head, it is necessary to assign correctly the bone material properties. The 3D FE models were able to predict the overall force-displacement curve, location and initiation of femur fractures. Moreover, despite its robustness, this 3D FE model is still limited to be used, within clinically acceptable time, for diagnostic purposes. To overcome this, the model was simplified into 2D model which has been preliminarily validated under identical boundary conditions and the results showed a good correlation with experiments. These studies have highlighted the potential of the finite element model based on quasi-brittle damage to become a complementary tool for predicting the risk of bone fracture.
132

Etude de la variabilité en fonction du sexe, de l'âge et de l'origine géographique de l'extrémité distale du fémur / Study of the sex, age and geography based variability in the distal femur

Cavaignac, Étienne 10 November 2017 (has links)
La morphologie des os humains varie en fonction du sexe, de l'âge et de l'ethnie. Cette variabilité de l'anatomie humaine peut aider à déterminer le sexe, l'âge et l'ethnie. Les outils utilisés pour de telles analyses sont classiquement des méthodes ostéométriques (longueur, angle, rapport de longueur) qui peuvent être sujettes à des biais d'analyse ou d'interprétation. L'analyse morphométrique géométrique 3D (MG) permet de limiter ces biais. Elle étudie et compare la forme d'un ou plusieurs objets en éliminant les effets liés à la taille de celui-ci. Nous n'avons pas retrouvé d'analyse du dimorphisme sexuel, ethnique et lié à l'âge de l'extrémité distale du fémur à l'aide de cette méthode. Le fémur est pourtant un des plus gros os du corps et il est souvent bien conservé dans les restes humains. L'objectif de ce travail était de montrer qu'il existe une différence de forme du fémur distal en fonction de l'âge, du sexe et de l'ethnie visualisable grâce à MG. Nous avons réalisé une MG de 482 scanners d'extrémité distale de fémur de sujets vivant dans le sud de la France et dans la région de Chongqing (chine). Les sujets présentant une pathologie osseuse ou articulaires ont été exclus. Dix landmarks ont été positionnés sur des reconstructions tridimentionelles. Nous avons également réalisé une analyse ostéométrique " classique " en plus de MG afin d'évaluer la vraisemblance de nos résultats. Les données ont été analysées par deux observateurs à deux temps différents. Nous avons calculé pour chaque landmark la variabilité inter et intraobservateur. Les landmarks choisis permettaient de caractériser la forme de l'extrémité distale du fémur. La première étape a consisté en la réalisation d'une analyse généralisée procrustre (GPA). Les coordonnées dans l'espace des landmarks ont été analysées en utilisant une analyse en composant principal (PCA). Une analyse discriminante a permis de vérifier le pourcentage de cas dans lequel le sexe, l'âge ou l'ethnie estimés étaient les bons. GPA retrouve une différence de forme statistiquement significative entre les sexes, en fonction de l'âge et entre les ethnies. PCA retrouve une différence de forme en fonction de l'âge, du sexe ou de l'ethnie qui représente respectivement 54,4 ;58,6 et 61,9% de la variabilité observée. Les taux d'assignement correct avec cette méthode étaient de 80% (âge) ; 77,3% (sexe) et 82 % (l'ethnie). L'analyse ostéométrique " classique " retrouvait des valeurs comparables à celles retrouvées dans la littérature. Le pourcentage d'erreur intra et inter observateur pour l'ensemble des landmarks n'excédait jamais 2%. Nous avons démontré que l'analyse MG du fémur distal permettait de mettre en évidence une variabilité en fonction du sexe, de l'âge et de l'ethnie de ce segment osseux. La reproductibilité élevée et la vraisemblance des résultats valident notre méthodologie. Cette différence de forme a des retombées directes en anthropobiologie mais aussi en orthopédie. Cette méthode d'assignation ne donne pas de résultats suffisamment précis pour être utilisée seule. Cependant, elle a l'avantage de pouvoir être utilisée dans des contextes d'autopsie virtuelle ou in vivo. Par ailleurs, par la présente étude nous réactualisons les données morphométriques de population contemporaine du sud de la France et aussi de la région de Chongqing en chine. Cette méthodologie adéquate et reproductible va permettre de réaliser des comparaisons diachroniques ainsi qu'inter ethnique. La validation de l'utilisation d'examen d'imagerie médicaux ouvre un champ nouveau en anthropologie physique. En ce qui concerne l'aspect orthopédique, cette variabilité questionne sur la nécessité ou non d'implant spécifique et surtout sur la nécessité de réévaluer de manière régulière la forme des prothèses de genou. / The shape of human bones varies based on age, sex and ethnicity. This variability in human anatomy can be used to determine a person's age, sex and ethnicity. Historically, the tools used for such analyses are osteometric methods (length, angle, length ratio) that can be plagued by analysis or interpretation biases. Three-dimensional geometric morphometric analysis (3D GM) can limit the impact of these biases. It is used to describe and compare the general shape of one or more objects by eliminating any size-related effects. To the best of our knowledge, this method has never been used to analyse the sexual dimorphism, ethnicity-related and age-related differences in the distal femur. The femur is one of the longest human bones and is often well preserved in human remains. The goal of this study was to demonstrate differences in the shape of the distal femur according to age, sex and ethnicity using GM. We carried out 3D GM on 482 CT scans of the distal femur of adults living in the South of France and in the Chongqing region of China. Subjects with bone or joint pathologies were excluded. Ten landmarks were defined on 3D reconstructions of the distal femur. A standard osteometric analysis was performed in addition to the GM analysis to evaluate the plausibility of our results. The data were analysed by two observers at two different times. This allowed us to calculate the inter- and intra-observer variability for each landmark. The chosen landmarks were used to characterise the shape of the distal femur. The first step consisted of a generalized Procrustes analysis (GPA). The landmarks' coordinates in space were analysed using a principal component analysis (PCA). A discriminant analysis was performed to determine the percentage of cases in which the sex, age or ethnicity was correctly estimated. The GPA found a statistically significant difference in the distal femur shape between different sexes, ethnicity groups and age groups. The PCA found that age, sex and ethnicity accounted for 54.4%, 58.6% and 61.9% of the observed variability in distal femur shape, respectively. Using this method, 80% of cases were assigned the correct age, 77.3% the correct sex and 82% the correct ethnic group. The results of the osteometric analysis were comparable to published values. The percentage error for the intra- and interobserver comparisons for all the landmarks was always less than 2%. In this study, MG analysis of the distal femur revealed age-related, sex-related and ethnicity-related variability in the distal femur. The high reproducibility and plausibility of our results validate our methodology. These shape differences have direct implications for anthropobiology and also orthopaedics. Although this method is not sufficiently accurate to be used alone, it has the advantage of being usable in the context of virtual or in vivo autopsy cases. Moreover, this study has updated the morphometric data for a modern population in the south of France and the Chongqing region of China. This reliable and accurate methodology can be used to perform diachronic and interethnic comparisons. Validation of this medical imaging modality opens new avenues in physical anthropology research. In the orthopaedics field, this variability means that the shape of implants used for knee arthroplasty should be re-assessed regularly and brings into question the need for gender-specific or ethnicity-specific implants.
133

3D Modeling and Finite Element Analysis of Femur After Removing Surgical Screws

Newman, Kyle D. 01 December 2016 (has links)
Often bone fractures are joined by inserting metal plates and screws to hold the fragmented bone under compression. However, after the fractured bone is healed removing the screws leaves holes in the bone which takes months to fill up and heal completely. The goal of this research is to investigate those voids specifically in a finite element model of a femur. The holes were found to experience high stress that can easily lead to crack propagations during everyday activities. Finite element models of femurs were modeled after two common fracture fixation systems, specifically just after the plates, rods and screws are removed. To observe the stress levels bones are likely to experience, common mechanical tests that are relevant to or associated with common daily activities were performed. While the 3-point bending tests did not yield significant results, the compression and torsion tests produced high stress areas near the screw holes. In certain cases, the von Mises’ stress reached 3.66 x 106 N/mm2. Our finite element modeling seeks to establish groundwork for future explorations on the holes created by fracture fixation hardware. In the future, this work will lead to redesigning of fixation systems with reduced stress concentration around the holes. Therefore, the initiation of new cracks around these holes will be limited during everyday activity.
134

Estudo histopatológico da implantação de nervo periférico no osso

Varanda, Denis [UNESP] 20 February 2015 (has links) (PDF)
Made available in DSpace on 2015-12-10T14:23:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-20. Added 1 bitstream(s) on 2015-12-10T14:29:15Z : No. of bitstreams: 1 000847943.pdf: 798739 bytes, checksum: f53b118e7c183c9c7d1e749a4ec9955a (MD5) / Introdução - Há diversas técnicas cirúrgicas para o tratamento dos neuromas doloridos, porém não há consenso em relação a mais eficaz. A implantação do neuroma ou do nervo dentro do osso é uma das cirurgias que proporciona bons resultados clínicos. Contudo, não há conhecimento detalhado sobre o destino do nervo ou neuroma implantado no osso. Objetivos - Os objetivos do estudo foram desenvolver modelo experimental de implantação de nervo no osso e analisar morfologicamente o destino no nervo implantado no osso. Material e Métodos - 24 ratos foram submetidos à implantação do nervo tibial caudal no terço distal do fêmur e estudados histológicamente nos períodos de 1, 3, 6, 13, 24 e 28 semanas por meio de microscopia ótica. Conclusões - Análise das imagens demonstrou que a implantação do nervo no osso desencadeia processo inflamatório que evolui da fase aguda para integração nervo-osso, sem formação de neuroma / Introduction - There are several surgical techniques for treatment of painful amputation neuroma. However no consensus has already been reached on the most effective treatment. Burying the neuroma or the nerve in the bone is one of the surgeries which provides good clinical findings. However, there is no deep knowledge of what happens to the nerve or buried neuroma in the bone. Objectives - The objectives of this study were to develop an experimental model of this surgical technique and to morphologically analyze the destiny of the implanted nerve in the bone. Materials and Methods - A total of 24 four rats underwent implantation of the caudal tibial nerve in the distal third of the femur. They were histologically studied in the periods of 1, 3, 6, 13, 24 and 28 weeks by optical microscopy. Conclusion - The analyses of the images showed that implantation of the nerve in the bone triggers an inflammatory response which evolves from the acute phase to the nerve-bone integration with no formation of neuroma
135

Associação da vitamina D e da força de preensão manual com úlceras de pressão e mortalidade em pacientes com fratura de fêmur proximal

Gumieiro, David Nicoletti [UNESP] 28 September 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-28Bitstream added on 2014-06-13T19:02:36Z : No. of bitstreams: 1 gumieiro_dn_dr_botfm.pdf: 945982 bytes, checksum: a2a3fac8c6ce527e4057b1b84b60ba2b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A frequência das fraturas do fêmur proximal tem aumentado nas últimas décadas e existe uma expectativa de que continue aumentando devido ao envelhecimento da população. Elas estão relacionadas à importante diminuição da independência, aumento da morbidade e mortalidade. As úlceras de pressão (UPs) são complicações pós-operatórias frequentes e os pacientes com fratura do fêmur proximal estão especialmente predispostos a elas. O teste da força de preensão manual (FPM) tem sido utilizado para detecção de pacientes com desnutrição energético-protéica e avaliação da força muscular, no entanto é pouco estudado em relação ao desenvolvimento de UPs. Além das alterações relacionadas aos macronutrientes, a deficiência de micronutrientes, como a vitamina D, também é pouco estudada em relação ao desenvolvimento de UPs e à mortalidade em pacientes com fratura do fêmur proximal. O objetivo deste estudo é avaliar se a concentração sérica de vitamina D e a força de preensão manual estão associadas ao aparecimento de úlceras de pressão e à mortalidade em pacientes com fratura do fêmur proximal 6 meses após a mesma. Foram avaliados prospectivamente pacientes consecutivos com fratura do fêmur proximal, com idade 65 anos, internados na enfermaria de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina de Botucatu – UNESP, no período de janeiro a dezembro de 2010. Nas primeiras 72 horas da admissão hospitalar, foram registrados dados demográficos, dados cirúrgicos referentes às fraturas, realizado questionário de frequência alimentar, avaliação antropométrica e o teste de FPM. Além disso, foi coletado sangue para dosagem de exames laboratoriais e dosagem sérica de vitamina D. No pósoperatório, foram avaliadas a presença ou não de UPs e a taxa de mortalidade em até 180 dias... / The prevalence of hip fractures is rising in the last decades and is expected to keep rising due to the aging of population. This type of fracture is related to a significant loss of independence, high morbidity and mortality. Pressure Ulcers (PU) are an important complication in this kind of patient. The handgrip strength (HGS) has been used to detect patients with malnutrition and to assess the muscle strength, but it’s relation with PU was not evaluated. In addition, the association of micronutrients such as vitamin D with PU development and mortality in patients with hip fractures was not yet studied. The aim of this study is to assess the role of serum levels of vitamin D and the hand grip strength as predictors of PU development and mortality in patients with hip fractures 6 months after the fracture. From January to December 2010, all consecutive patients older than 65 years with hip fractures, who were admitted to the orthopedic unit of the Botucatu Medical School Hospital, were prospectively evaluated. On admission, patient characteristics including age, gender, and concomitant diseases were recorded. Anthropometric measurements and food frequency questionnaire were performed, handgrip strength was measured, and blood samples were taken for analysis of serum biochemistry profile and serum vitamin D levels within the first 72 h of the patient’s admission after clinical stabilization. The PU development and mortality were evaluated during 180 days after fracture. One hundred patients with mean age of 80.7 ± 7.2 years old were studied. Seventy three percent were women and 61% presented PU 6 months after the fracture. Four patients died before surgery. After 6 months, there were 24% of deaths. The median of vitamin D intake corrected by energy was 2,39 (1,79 – 3,47) μg. The needs for ICU care, higher time from admission to surgery... (Complete abstract click electronic access below)
136

Acompanhamento do primeiro ano de evolução de idosos com fratura proximal de fêmur: aspectos epidemiológicos, cronologia da incidência de tromboembolismo venoso, evolução funcional e sobrevivência

Machado, Adriana Braga de Castro [UNESP] 19 July 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-19Bitstream added on 2014-06-13T21:07:34Z : No. of bitstreams: 1 machado_abc_dr_botfm.pdf: 2908111 bytes, checksum: 943cbe30c7037e83e7c7884f353a992a (MD5) / Not available
137

Estudo comparativo da osteotomia femoral varizante em cunha de abertura lateral orientada pelo método convencional X navegação / Comparative study of femoral varus osteotomy for lateral opening wedge computer assisted x conventional technique

Sergio Ricardo da Costa 06 August 2013 (has links)
INTRODUÇÃO: As osteotomias são formas reconhecidas de tratamento da osteoartrose de joelho em pacientes jovens com desvio do eixo mecânico. A navegação tem sido estudada nos últimos anos como um auxiliar importante nas cirurgias ortopédicas, principalmente artroplastias e oesteotomias. OBJETIVO: Objetivo deste trabalho é comparar, em curto prazo, os resultados radiográficos e clínicos da osteotomia femoral varizante em cunha de adição pelo método convencional e por navegação. MÉTODOS: Avaliamos 25 pacientes no Ambulatório de Especialidades do Hospital Geral de Pedreira, 12 submetidos à osteotomia femoral com navegação e 13 pela técnica convencional. RESULTADOS: Observamos para o grupo da osteotomia com navegação 73, 69 m de tempo de cirurgia com 12, 53 de desvio padrão; 59 m de tempo de garroteamento. Com relação ao alinhamento mecânico, no pré-operatório a média absoluta foi de 13,84 para cirurgia convencional e 14,4 para a técnica com navegação (p= 0.7432; IC95% 12,8 -15,4), No pós-operatório o alinhamento final mecânico variou de -2 a 3 e, não foi diferente entre as técnicas aplicadas (p= 0.1316; IC95% 0,08-1,24). Porém, obtivemos uma alta correlação (p= -0,68) para o grupo com navegação e uma baixa correlação (p= -0,07) para o grupo Resumo Sérgio Ricardo da Costa convencional. CONCLUSÃO: Observamos diferença estatística nos parâmetros: tempo de garroteamento e tempo de cirurgia. Não observamos diferença estatística nos parâmetros: alinhamento mecânico pré e pós; e no escore do HSS / INTRODUCTION: Osteotomies are recognized forms of treatment of knee osteoarthrosis in young patients with mechanical axis deviation. Navigation has been studied in recent years as an important aid in orthopedic surgeries, mainly in arthroplasty and osteotomies. OBJECTIVE: Objective of this study is to compare short-term clinical and radiographic results of femoral varus osteotomy wedge performed by conventional method and by navigation. METHODS: We evaluated 25 patients in Hospital Geral de Pedreira 12 underwent femoral osteotomy with navigation and 13 by conventional technique. RESULTS: As a result, time of surgery was statistically different between techniques (p = 0.0046) with a mean (standard deviation) of 73.69 m (12.53) for the conventional technique and 92.75 m (16.49) technique with navigation. Regarding to mechanical alignment, preoperative mean was 13.84 for conventional surgery and 14.4 for navigation technique (p = 0.7432, 95% CI 12.8 -15.4) Postoperatively final mechanic alignment ranged from -2 to 3, and was not different between the techniques applied (p = 0.1316, 95% CI 0.08 to 1.24). However, we obtained a high correlation (p = -0.68) for the group with navigation and a low correlation (p = -0.07) for the conventional group. CONCLUSION: There were statistical differences in the parameters: time of surgery and tourniquet time. No statistical difference in the parameters: mechanical alignment before and after, and the HSS score
138

Suplementação da vitamina d3 (colecalciferol) e 25-ohd3 (25-hidroxi-colecalciferol) e problemas locomotores e qualidade óssea em frangos de corte

Bresne, Carolina [UNESP] 25 April 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-25Bitstream added on 2014-06-13T19:56:26Z : No. of bitstreams: 1 bresne_c_me_botfmvz.pdf: 918891 bytes, checksum: decfbf9bcf0c32e25e4bb4c917c76fc2 (MD5) / Com o objetivo de avaliar a pododermatite e o desempenho em frangos de corte, foram alojados em aviário experimental da FMVZ-UNESP/Botucatu 750 frangos de corte machos da linhagem Cobb®, com densidade populacional de 12 aves/m2, por 42 dias. O delineamento experimental adotado foi inteiramente casualizado com cinco tratamentos e cinco repetições de 30 aves cada, totalizando 25 parcelas experimentais. Os tratamentos foram constituídos por duas fontes de suplementação de vitamina D (D3 e 25-OHD3). O tratamento 1, controle, seguiu as recomendações de Rostagno et al. (2011) para a vitamina D3, de acordo com cada fase de criação para frangos de corte. O tratamento 2 foi constituído de vitamina D3 (mesma dosagem do tratamento controle) + 1.400 UI de 25-OHD3; o tratamento 3 foi constituído de vitamina D3 (mesma dosagem do tratamento controle) + 2.800 UI de 25-OHD3; o tratamento 4 e o tratamento 5 foram constituídos apenas de vitamina D3 e, seus valores foram baseados na soma das doses em UI das duas fontes de vitamina D do tratamento 2 e do tratamento 3, respectivamente. Para o desempenho das aves foi calculado o consumo de ração, ganho de peso e conversão alimentar durante todo o período de criação, ao final foi calculada a viabilidade e o índice de eficiência produtiva. Aos 42 dias, 100 aves de cada tratamento foram avaliadas, no aviário, para pododermatite. Posteriormente as aves foram abatidas e realizadas análises histopatológicas do coxim plantar. Houve diferença pelo Teste de Quiquadrado (p<0,05) para a avaliação da incidência de pododermatite apenas para a perna esquerda. Os tratamentos não influenciaram o desempenho das aves e não foi observada diferença histopatológica entre lesões iniciais e severas, exceto em sua extensão. Conclui-se que as suplementações de... / Seven hundred and fifty Cobb® male broiler chickens were kept in a population density of 12 birds / m2 in the experimental aviary of FMVZ-UNESP/Botucatu during 42 days to evaluate the lesions of pododermatitis and performance. The experiment was carried out in a completely randomized design with five treatments and five repetitions of 30 birds each, totalizing 25 experimental parcels. Treatments were consisted of two sources of vitamin D (D3 and 25-OHD3). The first treatment (T1- control) followed the recommendations of Rostagno et al. (2011) for vitamin D3 according to each life stage of broiler chickens. Treatment 2 was the combination of vitamin D3 (the same level of control treatment) and 1,400 UI of 25-OHD3; treatment 3 was consisted of vitamin D3 (the same level of control treatment) and 2,800 UI of 25-OHD3; treatment 4 and 5 were consisted of only vitamin D3 and the levels were based on the sum of levels from the two sources of vitamin D3 of treatment 2 and 3, respectively. Feed intake, weight gain and feed:gain rate were calculated to evaluate the performance of broilers throughout the breeding period, viability and production efficiency index were also evaluated at the end. Pododermatitis and histological analyses of footpad were evaluated from one hundred broilers at 42 days of age. Through the Chi-Square Test (P<0.05) it could be seen a difference for pododermatitis incidence only for the left leg. Treatments did not affect the broiler performance and it was not observed histopathological differences between initial and severe lesions, except in its extension. In conclusion the supplementation of vitamin D3... (Complete abstract click electronic access below)
139

Estudo biomecânico de dois modelos de implante não cimentado para a artroplastia total do quadril em modelo canino / Biomechanical study between two new design for a uncemented femoral component to total hip arthroplasty in canine model

Faria, Luís Guilherme de 26 January 2018 (has links)
Submitted by Luis Guilherme de Faria null (lgfaria.medvet@ymail.com) on 2018-02-20T18:24:16Z No. of bitstreams: 1 TESE DE DOUTORADO - LUÍS GUILHERME DE FARIA - REPOSITÓRIO.pdf: 2930040 bytes, checksum: 40cde73090fb7af7b81a6b84ae05ed52 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-02-21T14:06:52Z (GMT) No. of bitstreams: 1 faria_lg_dr_jabo.pdf: 2930040 bytes, checksum: 40cde73090fb7af7b81a6b84ae05ed52 (MD5) / Made available in DSpace on 2018-02-21T14:06:52Z (GMT). No. of bitstreams: 1 faria_lg_dr_jabo.pdf: 2930040 bytes, checksum: 40cde73090fb7af7b81a6b84ae05ed52 (MD5) Previous issue date: 2018-01-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste estudo foi comparar as propriedades biomecânicas de dois modelos de hastes femorais da prótese total de quadril, não cimentada, modular e nacional. A haste A, possui uma extensão na base do colo do implante, denominado “colar”, já o implante B, possui a sua porção proximal abaulada. Buscou-se determinar qual dos dois modelos de hastes femorais tem melhor desempenho ao evitar, ou impedir, o afundamento (subsidence). Para tal, utilizou-se 8 pares de fêmures de cães adultos, machos e fêmeas, de diferentes raças e massa corporal de ±25 kg. Em cada fêmur, uma ostectomia da cabeça e do colo femoral foi realizada e inserido um dos implantes selecionados. As construções foram submetidas, previamente, à radiografia e densitometria óssea, a fim de determinar a homogeneidade da amostra. Logo em seguida, divididos em dois grupos, Haste A (8 fêmures) e Haste B (8 fêmures), aplicou-se carga de flexo-compressão, no eixo axial de cada amostra, em máquina universal de ensaios. A força máxima, a deflexão, a resistência à compressão e a energia foram as variáveis analisadas nos dois sistemas, assim, o Grupo B exibiu valores significativamente maiores (p≤0,05) para as variáveis resultantes deste estudo, com exceção da rigidez que, estatisticamente, considerou-se similar entre os dois grupos (p=0,2031). A média da força máxima no teste de compressão axial para o Grupo A foi de 1347±357 N e, para o Grupo B, de 1805±123 N (p≤0,0069). A média da deflexão para o Grupo A foi de 5547±2639 mm e, para o Grupo B, de 10033±3998 mm (p≤0,0056). Para a variável energia, a média da força máxima para o Grupo A foi de 6203±3488 N.mm, já para o Grupo B, foi de 12885±5056 N.mm (p≤0,0054). A média do módulo de deformação elástica, expresso em rigidez, no Grupo A foi de 860±160 N/mm, já no Grupo B, de 1011±305 N/mm (p≤0,0054). Os dados obtidos apresentavam distribuição normal e foram submetidos ao teste t pareado (p≤0,05). Constatou-se que a Haste B possui maior força máxima, deflexão e energia. Todavia, quanto a rigidez, ambas são eficientes em amortizar o impacto das forças axiais de flexo-compressão em fêmures cadavéricos de cães. / The goal of this study was to compare the biomechanical properties of two models of femoral stems of the total hip, uncemented, modular, and national (Brazil) prosthesis. The stem A has an extension at the base of the implant, called the "collar", and the implant B, has its convex proximal portion. We sought to determine which of the two models of femoral rods perform best by avoiding, or preventing, subsidence. To this end, we used eight pairs of femurs of adult dogs, male and female, of different races and body weight ± 25 kg. In each femur, an ostectomy of the head and femoral neck was performed and inserted one of the selected implants. The constructs were previously submitted to radiography and bone densitometry, in order to determine the homogeneity of the sample. Then, divided into two groups, Stem A (8 femurs) and Stem B (8 femurs), a flexo-compression load was applied on the axial axis of each sample in a universal testing machine. Maximum strength, deflection, compressive strength and energy were the variables analyzed in both systems, thus, Group B showed significantly higher values (p≤0.05) for the variables resulting from this study, except for the rigidity that, statistically, it was considered similar between the two groups (p=0.2031). The mean maximal force in the axial compression test for Group A was 1347±357 N and, for Group B, 1805 ± 123 N (p≤0.0069). The mean deflection for Group A was 5547 ± 2639 mm and, for Group B, 10033±3998 mm (p≤0.0056). For the energy variable, the mean of the maximum force for Group A was 6203±3488 N.mm, for Group B, it was 12885±5056 N.mm (p≤0.0054). The mean elastic strain modulus, expressed as rigidity, in Group A was 860±160 N/mm, in Group B, of 1011±305 N/mm (p≤0.0054). The obtained data presented normal distribution and were submitted to paired t test (p≤0.05). It was verified that Haste B has greater maximum strength, deflection and energy. However, for stiffness, both are efficient in amortizing the impact of axial flexion-compression forces on cadaverous femurs of dogs.
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Efeito de fitases de origem bacteriana no desempenho e qualidade óssea de frangos de corte / Effect of bacterial phytases origin on performance and bone quality broiler

Santos, Tatiane Souza dos [UNESP] 24 June 2016 (has links)
Submitted by Tatiane Souza dos Santos null (tatianesouza7@hotmail.com) on 2016-06-30T14:20:04Z No. of bitstreams: 1 Dissertação Tatiane Final.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-30T19:06:01Z (GMT) No. of bitstreams: 1 santos_ts_me_bot.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) / Made available in DSpace on 2016-06-30T19:06:01Z (GMT). No. of bitstreams: 1 santos_ts_me_bot.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) Previous issue date: 2016-06-24 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este estudo objetivou avaliar o efeito de três fitases comerciais derivadas da Escherichia coli, em dietas com níveis reduzidos de fósforo disponível, sobre o desempenho, fosfatase alcalina e ácida no soro, cálcio e fósforo no plasma e nos parâmetros ósseos (densitometria óssea, resistência óssea e cinzas) de frangos de corte aos 35 dias de idade. Dois mil e cem pintos machos de um dia de idade da linhagem Cobb®500 foram alojados em 70 boxes em delineamento experimental inteiramente casualizado em esquema fatorial, criados até 35 dias de idade dividido em fase inicial (I) e fase de crescimento (C). Nos tratamentos Controle positivo*(CP*) e Controle negativo*(CN*) foi praticada a valorização nutricional da fitase preconizada pelos fabricantes (0,12% Pd) em relação aos tratamentos Controle positivo (CP) e Controle negativo (CN). O esquema fatorial foi 2x4+2: dois níveis de fósforo disponível (Pd) (CP* - 0,33% (I) e 0,28% (C)) e (CN* - 0,23% (I) e 0,18% (C)) × fitases (A, B, C, ausente) + CP (0,45 (I) e 0,40% (C) Pd, sem fitase) e CN (redução de 0,10% de Pd: 0,35 (I) e 0,30% (C) Pd, sem fitase) totalizando 10 tratamentos com sete repetições. A ausência de fitase na dieta CN* promoveu os piores resultados para desempenho e qualidade óssea, além de elevar o nível de fosfatase alcalina e cálcio no sangue como resposta ao baixo nível de fósforo disponível na dieta. A inclusão de fitases nas dietas CP* melhorou o desempenho, com maior disponibilidade de minerais para o desenvolvimento ósseo. Desta forma, a densidade óssea da tíbia e do fêmur aumentaram, proporcionando ossos mais resistentes e com maior porcentagem de cinzas. Recomenda-se, quando da utilização das fitases para frangos de corte, utilizar apenas a valorização nutricional da enzima (-0,12% Pd), sem redução adicional de fósforo disponível nas dietas. / This study aimed to evaluate the effect of three commercial phytases derived from Escherichia coli, in diets with reduced levels of available phosphorus, on performance, alkaline and acid phosphtases in serum, calcium and phosphorus in plasma and bone parameters (bone density, bone strength and ash) of broilers at 35 d old. Two thousand one hundred male Cobb®500 broilers were housed in 70 pens in a completely randomized design in factorial arrangement, reared to 35 d old divided into starter phase (I) and the grower phase (G). In treatments positive control* (PC*) and negative control*(NC*) was practiced nutritional value of phytase recommended by the manufacturer (0.12% aP) in relation to positive control (PC) and negative control (NC) treatments. The factorial design was 2x4+2: two levels of available phosphorus (aP) (PC* - 0.33% (S) and 0.28 % (G)) and (NC* - 0.23% (S) and 0.18% (G)) × phytases (A, B, C, without) + PC (0.45 (S) and 0.40% (G) aP without phytase) and NC (decrease of 0.10 of aP: 0.35 (S) and 0.30% (G) aP without phytase) for a total 10 treatments with seven replicates. The absence of phytase in the diet NC* promoted the worst results for performance and bone quality, and increased the level of alkaline phosphatase and calcium in the blood in response to low levels of available phosphorus in diet. The inclusion of phytase in diets PC* improve the performance and increased availability of minerals for bone development. Thus, increased the bone density of the tibia and femur, bone strenght and bone ash. It is concluded that the inclusion phytase in diets PC* was sufficient to ensure good performance and bone quality. It is recommended, while the use of phytases for broiler use only the nutritional value of phytase (-0.12% aP) without additional reduction of available phosphorus in the diets. / FAPESP: 2014/27175-8

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