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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.
141

Biaxial Mechanical Evaluation of Uterosacral and Cardinal Ligaments

Baah-Dwomoh, Adwoa Sarpong 06 March 2018 (has links)
The uterosacral ligament (USL) and the cardinal ligament (CL) are two major suspensory tissues that provide structural support to the vagina/cervix/uterus complex. These ligaments have been studied mainly due for their role in the surgical repair for pelvic organ prolapse (POP). POP, which is the descent of a pelvic organ from its normal place towards the vaginal walls and into the vaginal cavity, affects an estimated 3.3 million women in the United States annually. Despite their important mechanical function, little is known about the elastic and viscoelastic properties of the USL and CL due to ethical concerns with in vivo testing of human tissues and the lack of accepted animal models. The goal of this first study is to help establish an appropriate animal model for studying the mechanics of these pelvic supportive ligaments. To achieve this, the first rigorous comparison of histological and planar equi-biaxial mechanical properties of the swine and human USLs was completed. Relative collagen, smooth muscle, and elastin contents were quantified from histological sections and the USL was found to have similar components in both species, with a comparable relative collagen content. Using the digital image correlation (DIC) method to calculate the in-plane Lagrangian strain, no differences in the peak strain during precon- ditioning/cyclic loading tests, secant modulus of the pre-creep/elastic response, and strain at the end of creep tests were detected in the USLs from the two species along both axial loading directions (the main in vivo loading direction and the direction that is perpendicular to it). Because these ligaments are subjected to repeated constant loads in vivo, the effect of re- peated biaxial loads at three different load levels (1 N, 2 N, or 3 N) on elastic and creep properties of the swine CL was investigated. The results showed that CL was elastically anisotropic, as statistical differences were found between the mean strains along the two axial loading directions for specimens at all three different load levels. The increase in strain over time by the end of the 3rd creep test was comparable along the axial loading direc- tions. The greatest mean normalized strain (or, equivalently, the largest increase in strain over time) was measured at the end of the 1st creep test, regardless of the equi-biaxial load magnitude or loading direction. Overall, these experimental findings validate the use of swine as an appropriate animal model and offer new knowledge of the mechanical properties of the USL and CL that can guide the development of better treatment methods such as surgical reconstruction for POP. / Ph. D.
142

Collagen and Fibrin Biopolymer Microthreads For Bioengineered Ligament Regeneration

Cornwell, Kevin G. 04 May 2007 (has links)
Rupture of the anterior cruciate ligament (ACL) of the knee leads to chronic joint instability and reduced range of motion while the long term results are marred by a high prevalence of degenerative joint disease especially osteoarthritis. Bundles of collagen threads have been widely investigated for the repair of torn ACL, but are limited by insufficient tissue ingrowth to repopulate and completely regenerate these grafts. We have developed a novel in vitro method of characterizing fiber-based thread matrices by probing their ability to promote tissue ingrowth from a wound margin as a measure of their ability to promote repopulation and regeneration. This method is useful in the optimization of thread scaffolds, and is sensitive enough to distinguish between subtle variations in biopolymer chemistry and organization. Furthermore, this method was used to characterize the effects of crosslinking on the cell outgrowth and correlated the findings with the mechanical properties of collagen threads. The results suggest that crosslinking is required to achieve sufficient mechanical properties for high stress applications such as ACL replacement, but regardless of technique, crosslinking attenuated the cell outgrowth properties of the threads. To improve the regenerative capacity of these scaffolds, novel fibrin microthread matrices were developed with a similar morphology to collagen threads and sufficient mechanical strength to be incorporated in composite thread scaffold systems. These fibrin microthreads were loaded with FGF-2, a potent mitogen and chemotactic agent that works synergistically with fibrin in regulating cell signaling and gene expression. Increases in fibroblast migration and proliferation in FGF-2-loaded fibrin threads were successfully demonstrated with the concomitant promotion of oriented, aligned, spindle-like fibroblast morphology. These results suggest that fibrin-FGF-2 microthreads have distinct advantages as a biomaterial for the rapid regeneration of injured tissues such as the ACL.
143

Knee kinematics during a novel hop test with an unanticipated change of direction for female floorball athletes and controls : Evaluation of within-session and test-retest reliability and assessment of knee function

Åström, William January 2016 (has links)
Introduction: The incidence of anterior cruciate ligament (ACL) injuries in female floorball is relativley high, and the risk for sustaining a second ACL injury is greater compared to previously uninjured. Existing evaluation tests in rehabilition may not be discriminative enough to guide decisions on return to sport Aim: To evaluate the withinAsession and testAretest reliability of knee kinematics in floorball athletes and controls during a hop encompassing a sudden unanticipated change of direction. A second aim was to investigate the discriminative validity by comparing the test outcomes between the athletes and a control group of nonAathletes. Method: 11 elite floorball athletes and 8 controls were tested on two occassions separated by one to three weeks. Knee kinematics, ground contact time and number of succesfull hops were analyzed. Relative reliability was quantifyed by Intraclass correlation coefficient (ICC) and absolute reliability by standard error of measurement (SEM). Results: ICCs for knee kinematics withinAsession reliability were excellent (0.83A0.96) for athletes and poor to excellent (0.40A0.94) for the controls. For the testAretest reliability, the athletes had good to excellent (0.56A0.96) reliability and the controls had poor to excellent (0.26A0.93) reliability. Only two measured kinematic variables were significantly different between the groups. Conclusion: This pilot study indictate good to excellent reliability for the majority of the kinematic variables tested and, therefore, it could be assumed to be adequatley reliable. Discriminative validity needs to be further evaluated in a larger material.
144

Proprioceptionens påverkan under en längre tids användning av knäortos hos personer med en främre korsbandsruptur.- En pilotstudie

Tegnér, Paulina January 2016 (has links)
No description available.
145

Hip extension range in dogs with chronic cranial cruciate ligament insufficiency

Van der Walt, Anna Margaretha 13 February 2009 (has links)
Canine cruciate ligament (CCL) rupture is a common veterinary orthopaedic problem, and has been associated with problems at the ipsilateral hip joint. However, the relationship between stifle and hip dysfunction has not been fully investigated. The purpose of this study was to establish whether CCL pathology is associated with a limitation in hip extension range large enough to affect gait. In a prospective, crosssectional study, passive and active hip extension range was determined in normal dogs as well as CCL deficient dogs. There was a significant reduction in ipsilateral passive hip extension range in the CCL deficient dogs (18.63º+/-7.57).There was a significant increase in hip extension range of the unaffected leg during gait compared to the normal group (7.03º+/-8.41). It was therefore concluded that canine CCL pathology directly affects hip extension range to a degree sufficient to affect normal gait.
146

Avaliação termográfica comparativa da articulação do joelho íntegro e de cães submetidos a duas técnicas de osteotomia corretiva para estabilização articular após ruptura de ligamento cruzado cranial / Thermographic evaluation of the normal canine stifle and comparative study of Tibial tuberosity advancement and Tibial plateau leveling osteotomy techniques

Nina, Marcos Ishimoto Della 17 December 2012 (has links)
A grande casuística relacionada à afecção ortopédica denominada ruptura do ligamento cruzado cranial na articulação fêmoro tíbio patelar canina tem gerado diversos estudos avaliando a biomecânica articular, fatores extrínsecos ao paciente e características metabólicas que poderiam influenciar na predisposição e no prognóstico dos pacientes acometidos por esta afecção. As dificuldades em identificar os diferentes níveis de instabilidade articular durante o diagnóstico e de estabilidade após o tratamento proposto, seja cirúrgico ou conservativo, provocou o desenvolvimento de diversas técnicas visando um melhor diagnóstico e estabilização articular pós operatória. Apesar da ampla variedade de técnicas cirúrgicas atualmente descritas para a insuficiência do ligamento cruzado cranial (LCC) em cães o tratamento ideal para esta freqüente condição ortopédica permanece indeterminado. Foram avaliados através da termografia infravermelha 30 pacientes caninos acima de 20 quilos sendo divididos em três grupos, o primeiro composto por dez animais hígidos onde foram analisados termograficamente os joelhos bilaterais a fim de padronizar valores térmicos de joelhos caninos normais, o segundo grupo composto por dez pacientes diagnosticados com instabilidade da articulação fêmoro tíbio patelar unilateral que foram submetidos a técnica cirúrgica de TTA para estabilização articular e o terceiro grupo composto por dez animais com diagnóstico de instabilidade da articulação fêmoro tíbio patelar unilateral que foram submetidos a técnica cirúrgica de TPLO para estabilização articular. Os grupos TTA e TPLO foram avaliados termograficamente em período pré operatório e nos momentos 30, 60 e 90 dias de pós operatório. Aos 30 dias de pós operatório houve diferença estatística com o grupo TPLO obtendo valores superiores ao grupo TTA. No período de 60 e 90 dias, não encontramos diferenças estatisticamente significantes nos valores comparativos dos membros operados em relação ao contralateral hígido podendo indicar que as duas técnicas cirúrgicas são capazes de trazer a articulação operada a uma condição de normalidade do ponto de vista termográfico. / The large number of cases related to the orthopedic condition called cranial cruciate ligament rupture in dogs has generated several studies evaluating the joint biomechanics, metabolic and environment characteristics that could influence the susceptibility and prognosis of patients affected by this condition. The difficulties in identifying the different levels of joint instability during diagnosis and joint stability after surgical or conservative treatment led to the development of several surgical techniques aiming a better diagnosis and joint stabilization. Despite the wide variety of surgical techniques currently described for the insufficiency of the cranial cruciate ligament (CCL) in dogs the ideal treatment for this common orthopedic condition remains uncertain. We evaluated using infrared thermography 30 canine patients over 20 kg. They were separated into three groups: the first group were consisted of ten healthy dogs, where we evaluated thermographycally their bilateral stifle in order to acquire thermal values of normal canine knees, the second group had ten patients diagnosed with instability of one stifle and were operated using the surgical technique called TTA and the third group were consisted of ten animals with a diagnosis of instability of unilateral stifle who underwent surgical procedure using the surgical technique called TPLO. The TTA and TPLO groups were evaluated thermographycally before surgery and at times 30, 60 and 90 days postoperatively. At 30 days evaluation we found significant differences between the TPLO and the TTA groups. At 60 and 90 days evaluation there were no significant differences between the operated limb in both groups and their contralateral not affected stifle. This results may indicate that both surgical techniques can bring the stifle back to normal thermographic parameters.
147

Análise biomecânica da articulação femoro-tíbio-patelar quanto à translação cranial da tíbia em relação a fêmur e da técnica extra-capsular com nylon e anel de aço para reparação do ligamento cruzado cranial em cães / Biomechanial analisis of extra-articular tecnique with nylon and stell ring to repair of cranial cruciate ligament in dogs

Romano, Leandro 09 June 2006 (has links)
As lesões ligamentares são provavelmente a causa mais comum de claudicação em membros pélvicos e de afecção degenerativa da cartilagem na articulação femoro-tíbio-patelar, vistas em cães. Objetivou-se avaliar a função biomecânica da articulação do joelho em cães, comparando a medida de deslocamento cranial e a rigidez articular da tíbia em relação ao fêmur com o ligamento cruzado cranial íntegro, seccionado e reparado cirurgicamente. Utilizou-se a máquina Kratos 5002, que permite gravar em tempo real os parâmetros força (N) e deslocamento/deformação em mm. O ensaio consitiu em aplicar força de (N) registrando assim a gaveta cranial. Para o joelho íntegro, a média de deslocamento em milímetros encontrada para três repetições foram de 3,39 ; 3,47; 3,53. Para o joelho lesado foram de 12,96; 13,24; 13,34. Para o joelho reparado foram de 4,05; 4,61; 4,42. Este estudo permite-nos concluir que após lesão a translação cranial do joelho lesado é acrescida em quatro vezes e a rigidez articular é diminuída em uma vez e meia. A análise estatística revelou diferença significante entre os dados do grupo íntegro e lesado, tanto para deslocamento quanto para rigidez (p<0,05). Para o joelho reparado a translação cranial não apresenta diferença estatística significante entretanto mostra que a rigidez articular não volta a normalidade. / Ligamentary lesions are probaly the most comum cause of hind limb lamness and the degenerative disease of the knee joint seem in dogs. The biomechanical function of the knee joint in dogs was made, comparing the cranial translation degree and articular stiffness of the tibia in relation to the femur, in normal joints, joints with rupture of cranial crucial ligament and cirurgicaly repared. Mechanical assays was realized by Kratos 5002 machine, and recorded in real time the parameters of force (N) and translation/deformation, in mm. The assay had consisted in to use a force(N) registering the cranial translation. To the normal knee, the deslocation media founded after 3 repetitions was 3,39 ; 3,47; 3,53. To the knee with surgical section was 12,96; 13,24; 13,34. To the repared knee was 4,05; 4,61; 4,42These study allows to conclude that the cranial translation is added in four times and the articular stiffness is reduced one and a half times when statistically compared. The statistical analysis reveled significant diference between groups to the cranial tranlation e articular stiffness (p<0,05). To the repared knee the cranial translation don?t reveled significant diference but the articular stiffiness seens anormal.
148

Characterization of cellular pathological changes in human patellar tendinosis: an in vitro approach.

January 2001 (has links)
by Pau Hon-Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 146-179). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.i / ABBREVIATIONS --- p.iii / ABSTRACT (English) --- p.v / ABSTRACT (Chinese) --- p.ix / FLOW CHART --- p.xi / INDEX OF FIGURES --- p.xxi / INDEX OF TABLES --- p.xxiv / PUBLICATION LIST --- p.xxv / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Basic Structure of Tendons --- p.3 / Chapter 1.2 --- Anatomy of Patellar Tendon --- p.9 / Chapter 1.3 --- Cellular Characteristics of Fibroblasts --- p.11 / Chapter 1.4 --- Healing Process in Tendons --- p.13 / Chapter 1.5 --- Chronic Tendon Disorder --- p.19 / Chapter 1.6 --- Aims and Objectives --- p.25 / Chapter 1.7 --- Study Plan --- p.26 / Chapter CHAPRER 2 --- MATERIALS AND METHODOLOGY --- p.35 / Chapter 2.1 --- Collection of human Tissues Samples --- p.38 / Chapter 2.2 --- Tissue Culture --- p.40 / Chapter 2.3 --- Preparation of Conditioned Medium --- p.46 / Chapter 2.4 --- Proliferation Response of Tendon Fibroblasts --- p.48 / Chapter 2.5 --- Invasion Assay --- p.53 / Chapter 2.6 --- Chick Chorioallantonic Membrane Model --- p.56 / Chapter 2.7 --- SDS-PAGE --- p.58 / Chapter 2.8 --- Enzyme Linked Immunosorbent Assay --- p.63 / Chapter 2.9 --- Immunocytochemical Staining --- p.68 / Chapter 2.10 --- Statistical Analysis --- p.69 / Chapter CHAPTER 3 --- RESULTS --- p.74 / Chapter 3.1 --- Patient's Information --- p.76 / Chapter 3.2 --- Primary Explant Cell Culture --- p.77 / Chapter 3.3 --- Proliferation Response of Tendon Fibroblasts --- p.79 / Chapter 3.4 --- Invasion Assay --- p.82 / Chapter 3.5 --- Chick Chorioallantonic Membrane Model --- p.83 / Chapter 3.6 --- SDS-PAGE --- p.85 / Chapter 3.7 --- Enzyme Linked Immunosorbent Assay --- p.86 / Chapter 3.8 --- Immunocytochemical Staining --- p.88 / Chapter CHAPTER 4 --- DISCUSSION --- p.116 / Chapter 4.1 --- Higher Proliferation Capacity of Tendinosis Fibroblasts --- p.118 / Chapter 4.2 --- Tendinosis Fibroblasts Secrete Angiogenesis Factors to Enhance Angiogenesis --- p.123 / Chapter 4.3 --- Tendinosis Fibroblasts Secrete More Proteolytic Enzyme --- p.126 / Chapter 4.4 --- Proinflammatory Characteristics in Tendinosis Fibroblasts --- p.129 / Chapter 4.5 --- Comparison of in vitro and Histological Study --- p.132 / Chapter 4.6 --- Tendinosis Fibroblasts Seems to be Transformed --- p.134 / Chapter 4.7 --- Limitation of Study --- p.136 / Chapter CHAPTER 5 --- FUTURE RESEARCH DIRECTION --- p.140 / Chapter 5.1 --- Further Exploration of the Factors Secreted in Tendinosis Fibroblasts --- p.141 / Chapter 5.2 --- Proteoglycan Synthesis in Tendinosis Fibroblasts --- p.142 / Chapter 5.3 --- Tendinosis Animal Model and Clinical Study --- p.143 / Chapter CHAPTER 6 --- CONCLUSION --- p.144 / BIBLIOGRAPHY --- p.146 / APPENDIX --- p.180
149

Estudo in vitro do efeito de cones de obturação endodôntica na biomodulação de fibroblastos de ligamento periodontal / In vitro study of the effect of endodontic obturation points on the biomodulation of periodontal ligament fibroblasts

Nogueira, Alessandra Fonseca Gambini 27 June 2017 (has links)
A obturação do canal radicular é uma etapa fundamental para o sucesso do tratamento endodôntico. É desejável que os materiais empregados nesta fase não interferiram negativamente com o reparo tecidual, mas preferencialmente estimulem a regeneração dos tecidos periapicais. Recentemente, cones de guta-percha combinados com material biocerâmico foram desenvolvidos com esta finalidade. Sendo assim, o objetivo deste estudo foi investigar o potencial citotóxico e biomodulador de cones de guta-percha convencionais, de cones de guta-percha contendo biocerâmica e de cones de polímero sobre células de ligamento periodontal in vitro. Cultura de fibroblastos de ligamento periodontal foi estabelecida a partir de terceiro molar humano. As células foram estimuladas com extratos de cones de guta-percha convencional, de cones de guta-percha contendo biocerâmica e de cones de polímero em diluição seriada para teste de viabilidade celular por meio do método MTT (Brometo de Difeniltetrazólio 3-(4,5-Dimetiltiazol-2-yl) após 72 h. Em seguida, a diluição de 1/5 foi empregada para estimulação das células por 72 h para detecção da expressão gênica de colágeno tipo I e proteína cementária 1 (CEMP-1) por RT-qPCR. Os dados foram estatisticamente analizados por meio de ANOVA sendo considerados significativos valores de p < 0,05. Os resultados observados de forma que, em extrato puro em extrato puro 1:1, houve comprometimento da viabilidade celular tanto para o extrato de cone de guta-percha quanto para o extrato do cone Cpoint podendo ser considerados citotóxicos. Nas outras diluições não houve diferença significativa neste parâmetro. Em relação à expressão gênica de colágeno, não foram observadas diferenças significativas quando da presença dos extratos. Para CEMP-1, significativa indução da expressão gênica foi observada para o cone de guta-percha. Conclui-se, através da análise dos resultados, que o cone de guta-percha e o cone de polímero são os mais citotóxicos em extrato puro, porém a guta-percha foi o único material que induziu uma expressão significativa de CEMP-1 que auxilia no reparo tecidual. O Col1 não foi induzido em nenhuma das amostras, porém também não foi inibido que indica que nenhum dos 3 tipos de cone interfere no reparo tecidual. / Root canal obturation is a fundamental step for successful endodontic treatment. It is desirable that the materials employed at this stage did not adversely interfere with tissue repair but rather stimulate the regeneration of the periapical tissues. Recently, gutta-percha points combined with bioceramic materials were developed for this purpose. Thus, the objective of this study was to investigate the cytotoxic and biomodulatory potential of conventional gutta-percha points, gutta-percha points containing bioceramics and polymer points on periodontal ligament cells in vitro. Culture of periodontal ligament fibroblasts was established from one human third molar. The cells were stimulated with extracts of cones of conventional gutta-percha points, gutta-percha containing bioceramics and polymer points in serial dilution for cell viability test using the MTT assay [Diphenyltetrazolium Bromide 3- (4,5)]. Next, the 1/5 dilution was used to stimulate the cells for 72 h to detect the gene expression of type I collagen and cement protein 1 (CEMP-1) by RT-qPCR. Data were statistically analyzed by means of ANOVA being considered significant values of p <0.05. The results observed was that in a pure 1: 1 extract, there was impairment of cell viability for both the guta-percha cone extract and the Cpoint cone extract and could be considered cytotoxic. At the other dilutions, no significant difference on this parameter was observed. Regarding the gene expression of collagen, no significant differences were observed at the presence of extracts. For CEMP-1, significant induction of gene expression was observed for gutta-percha points. In conclusion, the analysis of the results showed that the gutta-percha and polymer points are the most cytotoxic at pure extract, however gutta-percha was the only material that induced a significant expression of CEMP-1 which assists the tissue repair. Col1 was not induced in any of the samples but was also not inhibited indicating that none of the 3 cone types interfere in tissue repair.
150

Clast cell activity in a model of aseptic root resorption

Dreyer, Craig William. January 2002 (has links) (PDF)
Includes bibliographical references (leaves 355-403)

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