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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.
81

Efeitos das antocianinas, ácidos hidroxinâmicos e vitamina C sobre a biometria, composição corporal e qualidade óssea de ratos Wistar /

Rodrigues, Beatriz Almeida. January 2016 (has links)
Orientador: Lizandra Amoroso / Coorientador: Hugo Celso Dutra de Souza / Coorientador: Taís Harumi de Castro Sasahara / Banca: Fernanda Nogueira Valentin / Banca: Antônio Carlos Shimano / Resumo: A obesidade é um dos principais desafios para a saúde mundial e apresenta alta prevalência no homem e animais de companhia. Considerando a relevância dessa enfermidade, realizamos a presente pesquisa com o objetivo de avaliar o peso corporal, circunferência abdominal, índice de Lee, composição corporal, índice de Seedor, densidade mineral e resistência óssea de ratos Wistar tratados com dieta hipercalórica associada ou não à laranja vermelha, Citrus sinensis (L) Osbeck. O grupo que recebeu somente dieta hipercalórica apresentou menor massa magra em relação aos demais. Os animais tratados com fitoterápico associado à dieta hipercalórica apresentaram redução significativa na porcentagem de gordura em relação ao grupo tratado somente com dieta hipercalórica. Nos ensaios biomecânicos do úmero e fêmur não houve diferença na força máxima de ruptura, embora, no ensaio de compressão houve tendência de maior fragilidade óssea da cabeça do fêmur em ratos tratados somente com dieta hipercalórica. A associação de antocianinas, ácidos hidroxicinâmicos e vitamina C não interfere na densidade mineral óssea e na resistência biomecânica do úmero de ratos tratados com dieta padrão ou hipercalórica no período de cinco meses. Indivíduos resistentes à mudança de hábitos alimentares poderiam ser beneficiados pelo uso prolongado das antocianinas graças ao aumento da massa magra e redução da porcentagem de gordura após tratamento prolongado com laranja vermelha. / Abstract: Obesity is a major challenge to global health and is highly prevalent in humans and pets. Considering the importance of this disease, we carried out this research in order to evaluate body weight, waist circumference, Lee index, body composition, Seedor index, mineral density and bone strength of Wistar rats treated with high calorie diet with or without orange red, Citrus sinensis (L) Osbeck. We note that the animal that received only calorie diet showed less lean mass than the others. In addition, animals treated with herbal associated with calorie diet showed significant reduction in body fat percentage compared to the group treated only with high calorie diet. In biomechanical testing of the humerus and femur there was no difference in maximum breaking strength, although the compression test tended increased bone fragility of the femoral head in rats treated only with high calorie diet. The association anthocyanins, hydroxycinnamic acids and vitamin C does not interfere with bone mineral density and biomechanical strength of the humerus rats treated with standard hypercaloric diet during five months of treatment. Resistant individuals to changing eating habits could benefit by prolonged use of anthocyanins through increased lean mass and decreased body fat percentage after prolonged treatment with red orange. / Mestre
82

Minerais orgânicos na alimentação de potros / Organic mineral in diet of foals

Alessandra Soares 14 December 2007 (has links)
O objetivo do trabalho foi avaliar o uso de minerais orgânicos na alimentação de potros, avaliando a deposição óssea de Cálcio e Fósforo, através de biopsia e densitometria óssea, além das medidas de crescimento, de altura da cernelha e da garupa, perímetro torácico, joelho, canela e ganho de peso. Foram utilizados dez potros com idade entre 10 e 13 meses e peso aproximado de 221 kg, distribuídos aleatoriamente em dois tratamentos: dieta formulada com minerais orgânicos e dieta formulada com minerais inorgânicos, com cinco repetições por tratamento. A dieta foi composta de 40% de volumoso, feno de gramínea e 60% de concentrado, a qual foi adicionada 3% da mistura mineral orgânico ou inorgânico. Não foi observada diferença entre os tratamentos em relação ao consumo da deita, medidas de crescimento, e deposição óssea de cálcio e fósforo. No entanto, a deposição óssea dos animais do tratamento orgânico foram maiores quando comparada com as médias do tratamento inorgânico. Entretanto para a variável densitometria, a deposição óssea dos potros alimentados com fonte orgânica foi maior aos 90 dias, quando comparado com todos os animais do tratamento com fonte inorgânica. Os animais do tratamento orgânico apresentaram melhor ganho de peso médio e diário em relação aos animais que receberam mineral inorgânico. / The aim of this study was to evaluate the effects of mineral organic in the diet of foals, evaluating the bone mineral deposit of calcium and phosphorus, throughout biopsy and bone mineral density, measures of growing was also did measuring height withers and croup, thoracic circumference, knee, cannon and weight gain. Ten foals which approximated 10 and 13 months and almost 221 Kg weight each one were spread randomly into two treatments: diet with organic mineral and diet with inorganic mineral both with five repetitions for treatments. The diet were composed by 40% of roughage and 60% for concentrate, with was addition 3% of mixed mineral organic or inorganic. It was not detected any for consumption of diet, either for measures of growing and bone mineral concentration of calcium and phosphorus. Nevertheless, the average bone mineral concentration for organic treatment was better than mineral inorganic supplementation. However, the concentration in bone mineral was greater for organic treatment which was better for bone mineral density and weight. The bone deposition was better in 90 days of treatment. Therefore, the diet with organic mineral for foals probably better for bone mineral density and weight gain.
83

Avaliação estrutural do osso terceiro metacarpiano equino frente à implantação de biopolímero à base de mamona / Structural evaluation of the third metacarpal bone against the implantation of biopolymer based on castor oil

Mariana Baroni Selim 23 January 2014 (has links)
Uma série de novas estratégias vem sendo desenvolvidas com o objetivo de otimizar a reparação óssea, pois os métodos atualmente disponíveis em ortopedia humana e veterinária não apresentam resultados plenamente satisfatórios. Inúmeros pesquisadores dedicam-se ao desenvolvimento e estudo da compatibilidade de novos implantes com o propósito de acelerar a reparação óssea. O polímero a base de óleo de mamona tem chamado atenção para a sua aplicação como substituto ósseo, pois é um produto natural, biocompatível e com propriedades estruturais semelhantes às do tecido ósseo. Seis equinos foram submetidos à ostectomia na superfície diafisária dorsal de seus terceiros metacarpianos. Uma das falhas ósseas foi preenchida com o polímero a base de mamona e o outra, no membro contralateral permaneceu sem preenchimento, atuando como controle. Os animais foram acompanhados por um período de 120 dias após o procedimento através de monitoramento radiográfico da densidade óssea. Após este período, realizou-se biópsia para avaliação histológica por microscopias de luz e eletrônica de varredura. A densitometria óptica revelou valores médios de 14,17mmAl ± 1,722 e 16,33mmAl ±1,633 (p=0,027) para os grupos polímero e controle, respectivamente. A microscopia óptica de luz demonstrou maior porcentagem de tecido ósseo neoformado no grupo controle (50,15% ±14,83) quando comparado ao grupo polímero (26,94% ±12,06), com p0,0001. No entanto, a microscopia eletrônica de varredura permitiu observar que a qualidade do tecido ósseo formado na presença do biomaterial foi mantida. Além disso, não foram observadas reações adversas ao biomaterial, como a formação de tecido cicatricial ou reações de corpo estranho, levando a conclusão de que a poliuretana de óleo de mamona pode ser considerada adequada ao preenchimento de falhas ósseas em equinos, uma vez que desmonstrou compatibilidade e osteocondutividade. / A series of new strategies have been developed in order to optimize bone repair, because the methods currently available for human and veterinary orthopedics have no fully satisfactory results. Many researchers have dedicated to develop and study the compatibility of new implants in order to accelerate bone repair. The polymer of castor oil have drawn attention for its application as a bone substitute because it is a natural, biocompatible and have structural properties similar to bone tissue. Six horses were submited to ostectomy on the dorsal surface of its third metacarpal bone. One of the bone defects was filled with polymer of castor oil and the other remained unfilled, as a control group. The animals were followed for a period of 120 days after the procedure by monitoring radiographic bone density. After this period, a biopsy was performed for histological evaluation by light and scanning electron microscopy. The optical densitometry revealed medium values of 14.17mmAl ± 1.722 and 16.33mmAl ± 1.633 (p = 0.027) for the polymer and control groups, respectively. The light microscopy showed a higher percentage of new bone formation in the control group ( 50.15% ± 14.83 ) than in the polymer group ( 26.94 % ± 12.06 ) , with p 0.0001. However, scanning electron microscopy allowed to observe that the quality of bone formation tissue in the presence of biomaterial was maintained. Furthermore, there were no adverse reactions to biomaterial, such as scar formation or as a foreign body reaction, allowing to conclude that the polymer of castor oil can be considered suitable to fill bone defects in horses, since it demonstrated compatibility and osteoconductivity.
84

Estudo comparativo da densidade mineral óssea (DMO) em gatos domésticos (felis catus) castrados e não castrados, por meio da técnica de densitometria óptica radiográfica / Comparative study of bone mineral density (BMD) of sterilized and non-sterilized domestic cats (felis catus) by using radiographic optic densitometry technique

Marcia Lembo 24 November 2006 (has links)
Através da técnica de Densitometria Óptica Radiográfica consegue-se aferir o conteúdo mineral do osso com auxílio de imagens radiográficas, demonstrando ser uma metodologia precisa, confiável e de baixo custo. Procurou-se comparar os valores da densidade mineral óssea em gatos castrados precocemente - antes da puberdade - e gatos inteiros. O grupo experimental foi composto de 59 animais, separados em fêmeas e machos, castrados e inteiros. As densidades ópticas foram medidas por meio do programa de processamento de imagens ImageLab. Foram estudadas as correlações entre os valores de DMO, peso e sexo. Os gatos machos apresentaram valores de DMO e peso maiores que as fêmeas (P<0,001). Quando separados em machos castrados e inteiros e fêmeas castradas e inteiras, os gatos machos inteiros apresentaram maior valor de DMO, independentemente do peso. Entre as fêmeas não houve diferença significativa com os valores de DMO para os animais castrados e inteiros já os gatos machos castrados apresentaram valores de DMO semelhantes ao das fêmeas castradas demonstrando que com a castração precoce há uma diminuição da densidade mineral óssea. A correlação entre peso e a DMO se mostrou mais importante nos animais inteiros que nos castrados demonstrando que a interdependência entre peso e DMO varia com a ação hormonal. Os valores médios de DMO obtidos foram de 3,7±0,44mmAl para o grupo total de fêmeas, sendo de 3,69±0,56mmAl para as fêmeas castradas e 3,72±0,25mmAl para as fêmeas inteiras. Foram de 4,39±0,5mmAl Para o grupo total de machos, sendo de 4,52±0,38mmAl para ao machos inteiros e de 3,92±0,4mmAl para os machos castrados. / Radiographic Optic Densitometry has proven itself to be a precise, reliable, and low-cost methodology that enables analysis of bone mineral content with the aid of radiographic images. A study was conducted in which the bone mineral density of cats sterilized in pre-pubescence was compared to that of non-sterilized cats. The experimental group was composed of 59 animals, which were then divided into male and female groups, as well as into sterilized and non-sterilized groups. The optic densities of these animals were measured by the image processing program software, ImageLab. The correlations between the values of BMD, weight and sex had been studied. The male cats had presented higher values of BMD and weight than female cats (P<0,001). When comparisons were made between spayed and non-spayed females and neutered and non-neutered males, the non-neutered male cats had presented higher value of BMD, independent of their weight value. As for the females, there were no significant differences in the values of BMD between spayed and non-spayed females. However, the neutered male cats presented similar values of BMD as spayed females. This illustrates that sterilization causes a reduction in bone mineral density. The correlation between weight and the BMD was more significant in the non-sterilized animal group than in the sterilized group, demonstrating that the interdependence between weight and BMD varies according to hormonal action. The average values of obtained BMD were 3,7±0,44mmAl for the whole female group, and more specifically, 3,69±0,56mmAl for spayed females and 3,72±0,25mmAl for the non-spayed females. As for the male group, the average BMD value for the whole group was 4,39±0,5mmAl. However, the average BMD value was 4,52±0,38mmAl for the non-castrated males and 3,92±0,4mmAl for the castrated males.
85

Uso do decanoato de nandrolona no tratamento da não união óssea em fraturas do rádio - estudo experimental em coelhos (oryctolagus cuniculus) /

Dissenha, Adrielly January 2019 (has links)
Orientador: Bruno Watanabe Minto / Resumo: O objetivo da pesquisa foi avaliar a eficácia do Decanoato de Nandrolona (DN) em fraturas do rádio após indução da não união óssea por defeito segmentar. Foram utilizados 47 coelhos, da raça Nova Zelândia Branco, com peso médio de 3,8 kg, divididos aleatoriamente em grupos de 8 animais. Os grupos Controle Machos (GCM) e Controle Fêmeas (GCF) foram submetidos à eutanásia aos 45 dias, os grupos Nandrolona Machos (GNM) e Nandrolona Fêmeas (GNF) tratados com aplicações semanais de DN na dose de 10mg/kg, via intramuscular (IM) durante 4 semanas. Os Grupos Placebo Machos (GPM) e Grupo Placebo Fêmeas (GPF), tratados com aplicações semanais de NaCl 0,9% (IM), durante o mesmo período. Foi realizado exame radiográfico após a cirurgia e aos 15, 30, 45, 60, 75 e 90 dias. Os animais dos grupos GNM, GNF, GPM e GPF foram submetidos à eutanásia aos 90 dias. Realizou-se exame de densitometria óssea do rádio dissecado após a eutanásia em todos os grupos, bem como análise histológica. Para as variáveis não-paramétricas utilizou-se o teste de Kruskal-Wallis. Para as variáveis paramétricas foi utilizado o teste Shapiro-Wilk, ambos a 5% de significância. Radiograficamente, os grupos tratados com DN apresentaram média de escore superior aos demais grupos na formação de calo ósseo. Na análise densitométrica, também foi observada uma melhora significativa ao parâmetro de composição mineral óssea (BMC) nos grupos GNM e GNF. Os machos apresentaram maiores médias para os parâmetros conteúdo mineral ósse... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
86

Bone adaptation under mechanical influence: regional differences in bone mineral density, degree of mineralisation, mirco-arhitecture evaluated by pQCT, BSE imaging and microCT. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Lai Yau Ming. / "August 2006." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 260-290). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
87

Ultrasound Characterization of Structure and Density of Coral as a Model for Trabecular Bone

Sun, Yurong 08 August 2000 (has links)
"The goal of this thesis work has been to investigate improved diagnostic methods for both detecting osteoporosis and estimating fracture risk non-invasively, by assessing bone mass density (BMD) and bone microstructure. It evaluates new approaches for analyzing through-transmission ultrasound signals using coral samples as models for trabecular bone. The results of BUA, impulse response of coral samples and the angular decorrelation function of coral samples indicate that these ultrasound parameters may be useful in detecting changes in both bone mineral density (BMD) and the presence of dominant trabecular bone structure axis. "
88

Clinical and phantom-based studies of the validity and value of quantitative radiological hip structural analysis

Khoo, Benjamin Cheng Choon January 2008 (has links)
[Truncated abstract] Areal bone mineral density (BMD) is measured routinely in the clinic by a quantitative radiological technique, dual-energy X-ray absorptiometry (DXA). BMD is used widely to assess non-invasively but indirectly the mechanical fragility of bone and consequently is able to predict fracture risk. While BMD correlates well with in vitro measurements of bone strength it does not directly measure a mechanical property; half of incident minimally traumatic fractures in women occur with BMD values above the World Health Organisation defined threshold for osteoporosis. This arises partly because the mechanical strength of bone is dependent on its structural geometry and material strength as well as bone mineral mass. Essentially, bones fracture when load stresses exceed the mechanical capacity of the material to withstand them. The structural geometry (i.e., the amount of bone tissue and its complex three-dimensional arrangement within the macroscopic bone envelope) defines the stresses produced by a given load, while the intrinsic load capacity of the material is defined by the composition and microstructure of the bone tissue itself. Hip structural analysis (HSA) is a technique that elucidates the structural geometric component of bone strength; essentially combining information available from conventional DXA images of the proximal femur with a biomechanical beam model based on the stresses arising in a combination of pure bending and axial compression. A version of HSA has recently been released commercially, and has obtained US Food and Drug Administration approval for its clinical application. ... Given the acknowledged limitations of the HSA method when applied to 2-D projection images, a 3-D approach to structural geometry, using imaging modalities such as pQCT and QCT or a recently introduced version of DXA that mimics QCT, is indicated for the future. With that in mind and the possibility of the anthropometric phantom being adopted for future accuracy and precision assessments, improvements in the design of this phantom are recommended. Studies to better understand and verify Contents v the relevance of the 'local buckling' phenomenon as a structural geometric factor in the genesis of macro-fractures are also recommended. In summary, it is essential that superior (compared to BMD) non-invasively determined clinical predictors of bone fragility leading to fracture be investigated. Structural geometric variables are potential candidates. This has led to consideration of; (i) the need to progress beyond BMD for a more sensitive and specific bone strength measurement; (ii) theoretical advantages of structural geometry over BMD; (iii) limitations of the current HSA technique based on DXA, including those introduced by its restrictive assumptions; (iv) the value of HSA in longitudinal studies, exemplified by the 'normal' but rapid skeletal changes seen in human lactation, with possible implications for an analogous study of the menopause; and (v) an investigation, using a custom-designed anthropometric phantom, of the adaptation of HSA to certain emerging imaging modalities and methods able to resolve bone structural geometry in three dimensions.
89

Hips at risk osteoporosis and prevention of hip fractures

Ekman, Anna January 2001 (has links)
<p>Hip fractures are the most serious consequence of osteoporosis, and are one important cause of morbidity and mortality among the elderly. Prophylactic treatment for hip fractures are now available. Early detection of individuals with increased risk for hip fractures is therefor of great interest. A subset of non-institutionalised patients with a first hip fracture (cases;n=l18) and controls (n=263), aged 65-85 years, underwent dual X-ray absorptiometry (DXA) of the femoral neck, quantitative ultrasound (QUS) of the heel and phalanges and radiographic absorptiometry (RA) of the phalanges. The entire cohort was followed for approximately four years or to death. In women, DXA of the proximal femur and QUS of the heel showed a high predictive value for an incident first hip fracture, adjusted odds ratio (OR) 3.6 (95% confidence interval (CI) 2.4-5.5) and 3.4 (95%CI 2.2-5.0) respectively. The association was even stronger in men, but only for DXA of the proximal femu,r with an adjusted OR of4.8 (95%CI 2.3-9.9). Bone densitometry at non-weight-bearing sites, QUS and RA of the phalanges did not discriminate female cases from controls, but proved capable of separating male cases from controls. The risk of death was higher in cases than in controls, with a multivariate rate ratio (RR) of 3.4 (95%CI 1.7-7.0). There was no significant association between bone density and mortality. </p><p>Nursing home residents underwent QUS of the heel and phalanges. Almost all of the female residents and 51% of the male residents were, if the WHO-criterion for osteoporosis was applied, osteoporotic as assessed by heel and finger QUS. The QUS values were approximately 1.5 SD lower than expected for age and gender. </p><p>In this randomised controlled intervention study we evaluated the effect of external hip protectors in nursing home residents; 302 residents were allocated to wear such protectors and 442 were controls. External hip protectors were found to be effective in preventing hip fractures in nursing home residents, with an adjusted relative risk for hip fracture of 0.33 (CI 0.11 - 1.00). </p>
90

Hips at risk osteoporosis and prevention of hip fractures

Ekman, Anna January 2001 (has links)
Hip fractures are the most serious consequence of osteoporosis, and are one important cause of morbidity and mortality among the elderly. Prophylactic treatment for hip fractures are now available. Early detection of individuals with increased risk for hip fractures is therefor of great interest. A subset of non-institutionalised patients with a first hip fracture (cases;n=l18) and controls (n=263), aged 65-85 years, underwent dual X-ray absorptiometry (DXA) of the femoral neck, quantitative ultrasound (QUS) of the heel and phalanges and radiographic absorptiometry (RA) of the phalanges. The entire cohort was followed for approximately four years or to death. In women, DXA of the proximal femur and QUS of the heel showed a high predictive value for an incident first hip fracture, adjusted odds ratio (OR) 3.6 (95% confidence interval (CI) 2.4-5.5) and 3.4 (95%CI 2.2-5.0) respectively. The association was even stronger in men, but only for DXA of the proximal femu,r with an adjusted OR of4.8 (95%CI 2.3-9.9). Bone densitometry at non-weight-bearing sites, QUS and RA of the phalanges did not discriminate female cases from controls, but proved capable of separating male cases from controls. The risk of death was higher in cases than in controls, with a multivariate rate ratio (RR) of 3.4 (95%CI 1.7-7.0). There was no significant association between bone density and mortality. Nursing home residents underwent QUS of the heel and phalanges. Almost all of the female residents and 51% of the male residents were, if the WHO-criterion for osteoporosis was applied, osteoporotic as assessed by heel and finger QUS. The QUS values were approximately 1.5 SD lower than expected for age and gender. In this randomised controlled intervention study we evaluated the effect of external hip protectors in nursing home residents; 302 residents were allocated to wear such protectors and 442 were controls. External hip protectors were found to be effective in preventing hip fractures in nursing home residents, with an adjusted relative risk for hip fracture of 0.33 (CI 0.11 - 1.00).

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