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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.
111

Implante de tecido prostático do cão na ostectomia parcial do rádio em coelhos

Lacreta Junior, Antonio Carlos Cunha [UNESP] 25 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-25Bitstream added on 2014-06-13T20:41:25Z : No. of bitstreams: 1 lacretajunior_acc_dr_jabo.pdf: 805914 bytes, checksum: 44e9be8105f00a126bb8355d24887832 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O retardamento ou a ausência do processo de consolidação óssea nas correções cirúrgicas das fraturas são situações indesejadas por cirurgiões, haja vista que às vezes se torna um problema de difícil resolução na cirúrgia ortopédica. A união óssea inicia-se imediatamente após a fratura por meio de mecanismos fisiológicos com fases bem definidas. Cada uma dessas fases é mediada por substâncias biológicas distintas específicas e indispensáveis no processo completo da neofomação óssea. Essas substâncias biológicas podem ativar ou impedir a osteogênese dependendo da sua presença, quantidade ou qualidade em cada fase da consolidação óssea. Dentre os inúmeros oteoindutores biológicos e sintéticos existentes, a próstata do cão, recentemente testada mostrou-se efetiva na estimulação da osteogênese. O presente estudo consistiu em avaliar a capacidade osteindutora da próstata do cão em ossos longos, utilizando-a na ostectomia parcial do rádio em coelhos. Os coelhos foram distribuidos em dois grupos (controle e tratado), cada qual com dois subgrupos de 30 e 60 dias, que foram submetidos a ostectomia parcial do rádio, e cujos animais do grupo tratado recebem o implante do fragmento da próstata do cão. Segundo os aspectos clínicos, radiológicos e histológicos, ao longo do tempo, após o procedimento cirúrgico, os resultados sugerem que a próstata induz a osteogênese, e que seu uso nas cirurgias ortopédicas poderá ser uma ferramenta importante no auxílio à consolidação óssea. / The retardation or absence of the process of bone healing in the surgical corrections of the fractures are situations not desired for surgeons, has seen that the times if it becomes a problem of dificult in the orthopaedic surgery. The bone healing immediately initiates after the fracture by means of physiological mechanisms with well defined phases. Each one of these phases is mediated by specific and indispensable distinst substances biological in the complete process of the new bone formation. These biological substances can activate or hinder the osteogenesis depending on its presence, amount or quality in each phase the bone helding. Amongst the innumerale existing biological and syntheticosteoinductors, the prostate of the dog, recently tested reveled effective in the simulation of osteogenesis. The present study in consisted of evaluating the osteinduction capacity of the prostate of the dog in long bones, using it in the partial radius ostectomy in rabbits. The rabbits had been divided in two groups (control and treated) and four sub-groups, had been submitted the partial radius ostectomy, whwere they had received the implantation of the dog prostate pieces. After the surgery had been evaluated by clinical, radiography and histological examination. The results had demosntred that prostate induces osteogenesis, and thatits use in the orthopaedics surgeries could bean important tool in the aid of the bone healing.
112

Caracterização do aço inoxidável austenítico UNS S31254 em meio de NaCI 0,11 mol L-1 visando seu emprego em implantes ortopédicos / Electrochemical characterization of UNS S31254 austenitic stainless steel in 0.11 mol L-1 NaCl medium in order to propose its application in orthopaedic implants

Monica Luisa Chaves de Andrade Afonso 27 September 2006 (has links)
Foi feita a caracterização eletroquímica do aço inoxidável austenítico UNS S31254 em meio de NaCl 0,11 mol L-1 na ausência e presença de soro albumina bovina (BSA) visando seu emprego em implantes ortopédicos. Foram empregadas como técnicas: medidas de potencial de circuito aberto, curvas de polarização, cronoamperometria, EIE, XPS, MEV, EDS e EEO. O comportamento eletroquímico do aço 254 foi comparado com o de outros aços empregados em implantes ortopédicos (ISO 5832-9, ASTM F138, e AISI 316L) na ausência e presença de BSA. O aço 254 se mostrou semelhante ao ISO 5832-9: encontra-se passivado desde o potencial de corrosão até o de transpassivação; a presença de inclusões de óxidos de cálcio e alumínio no aço 254 foi considerada a responsável por um potencial de transpassivação 100 mV menos positivo do que o observado com o aço ISO 5832-9. Foi detectada. além de óxido de Cr(III), a presença de Mo na forma Mo(VI) no filme passivo do aço 254. A ação da BSA, ora passivante ora catalisadora, depende de sua concentração, da natureza do substrato metálico, e do potencial na interfase metal-solução. A BSA modifica o mecanismo de oxidação do aço 254 e inibe seletivamente a dissolução dos seus elementos constituintes, em particular, níquel e cromo. / The electrochemical characterization of UNS S31254 has been made in 0.11 mol L-1 NaCl medium in the absence and presence of bovine serum albumin (BSA) in order to propose its application in orthopaedic implants. The techniques employed were: open circuit potential measurements, polarization curves, chronoamperometry, EIS, XPS, SEM, EDS and EEO. The electrochemical behavior of 254 SS was compared to that observed for ISO 5832-9, ASTM F138 and AISI 316L stainless steels, used in orthopedic implants, in the absence and presence of BSA. 254 SS is similar to ISO 5832-9 SS: it is passivated on the potential range between the corrosion and the transpassivation potentials; the presence of calcium and aluminum oxides can be responsible for the shift of about 100 mV to less positive potentials on the transpassivation potential when compared to ISO 5832-9 SS. The presence of Mo(VI) was detected beside Cr(III) as passivating film for 254 SS. BSA action depends on its concentration, the nature of the metallic substract and on the potential in the metal-solution interphase. BSA changes the oxidation mechanism of 254 SS and promotes the selective dissolution of the elements particularly nickel and chromium.
113

Implante de tecido prostático do cão na ostectomia parcial do rádio em coelhos /

Lacreta Junior, Antonio Carlos Cunha. January 2008 (has links)
Orientador: Júlio Carlos Canola / Banca: Paola Castro Moraes / Banca: Naida Cristina Borges / Banca: José Wanderley Cattelan / Banca: Aureo Evangelista Santana / Resumo: O retardamento ou a ausência do processo de consolidação óssea nas correções cirúrgicas das fraturas são situações indesejadas por cirurgiões, haja vista que às vezes se torna um problema de difícil resolução na cirúrgia ortopédica. A união óssea inicia-se imediatamente após a fratura por meio de mecanismos fisiológicos com fases bem definidas. Cada uma dessas fases é mediada por substâncias biológicas distintas específicas e indispensáveis no processo completo da neofomação óssea. Essas substâncias biológicas podem ativar ou impedir a osteogênese dependendo da sua presença, quantidade ou qualidade em cada fase da consolidação óssea. Dentre os inúmeros oteoindutores biológicos e sintéticos existentes, a próstata do cão, recentemente testada mostrou-se efetiva na estimulação da osteogênese. O presente estudo consistiu em avaliar a capacidade osteindutora da próstata do cão em ossos longos, utilizando-a na ostectomia parcial do rádio em coelhos. Os coelhos foram distribuidos em dois grupos (controle e tratado), cada qual com dois subgrupos de 30 e 60 dias, que foram submetidos a ostectomia parcial do rádio, e cujos animais do grupo tratado recebem o implante do fragmento da próstata do cão. Segundo os aspectos clínicos, radiológicos e histológicos, ao longo do tempo, após o procedimento cirúrgico, os resultados sugerem que a próstata induz a osteogênese, e que seu uso nas cirurgias ortopédicas poderá ser uma ferramenta importante no auxílio à consolidação óssea. / Abstract: The retardation or absence of the process of bone healing in the surgical corrections of the fractures are situations not desired for surgeons, has seen that the times if it becomes a problem of dificult in the orthopaedic surgery. The bone healing immediately initiates after the fracture by means of physiological mechanisms with well defined phases. Each one of these phases is mediated by specific and indispensable distinst substances biological in the complete process of the new bone formation. These biological substances can activate or hinder the osteogenesis depending on its presence, amount or quality in each phase the bone helding. Amongst the innumerale existing biological and syntheticosteoinductors, the prostate of the dog, recently tested reveled effective in the simulation of osteogenesis. The present study in consisted of evaluating the osteinduction capacity of the prostate of the dog in long bones, using it in the partial radius ostectomy in rabbits. The rabbits had been divided in two groups (control and treated) and four sub-groups, had been submitted the partial radius ostectomy, whwere they had received the implantation of the dog prostate pieces. After the surgery had been evaluated by clinical, radiography and histological examination. The results had demosntred that prostate induces osteogenesis, and thatits use in the orthopaedics surgeries could bean important tool in the aid of the bone healing. / Doutor
114

Molecular Mechanisms Leading to Interleukin-1β Release by Macrophages in Response to Wear and Corrosion Products from Metal Implants

Archibald, Jennifer 29 May 2020 (has links)
Wear particles and ions from cobalt-chromium-molybdenum (CoCrMo)-based implants have been shown to cause adverse immune responses, including periprosthetic osteolysis leading to aseptic loosening, the main cause of implant failure. Previous studies have shown that these wear and corrosion products can lead to the release of inflammatory cytokines, including interleukin-1β (IL-1β), suggesting the involvement of the NLRP3 inflammasome. However, the mechanisms leading to IL-1β release have not been fully elucidated. The primary objectives of this thesis were to determine if, in murine macrophages, IL-1β release induced by micrometre-size CoCrMo particles and nanometre-size chromium oxide (Cr2O3) particles is: 1. Caspase-1-dependent; 2. Reduction-oxidation (redox)-dependent; and 3. NLRP3 inflammasome-dependent. Additionally, the effects of metal ions (Co2+, Cr3+, and Ni2+) on NLRP3 inflammasome activation and the effects of matrix metalloproteinase (MMP) inhibition on IL-1β release induced by CoCrMo particles were analyzed. Results showed that IL-1β release induced by CoCrMo particles was partly caspase-1-, redox-, and MMP-dependent, but NLRP3 inflammasome-independent. On the other hand, IL-1β release induced by Cr2O3 particles appeared to be NLRP3 inflammasome-dependent. Finally, IL-1β release induced by Cr3+, but not Co2+, appeared to be NLRP3 inflammasome-dependent, while Ni2+-induced IL-1β release appeared to be only partially NLRP3 inflammasome-dependent, suggesting that other pathways may also be involved. These findings, which provide additional insights into the mechanisms leading to IL-1β release induced by wear particles and ions from CoCrMo-based implants, may help the future development of therapeutic treatments to modulate wear product-induced inflammation and increase implant longevity.
115

Hexahedral meshing of subject-specific anatomic structures using registered building blocks

Natarajan, Amla 01 July 2010 (has links)
To extend the use of computational techniques like finite element analysis to clinical settings, it would be beneficial to have the ability to generate a unique model for every subject quickly and efficiently. To this end, we previously developed two mapped meshing tools that utilized force and displacement control to map a template mesh to a subject-specific surface. This work is an extension of those methods; the objective of this study was to map a template block structure, common to multi-block meshing techniques, to a subject-specific surface. The rationale was that the blocks are considerably less refined and may be readily edited, thereby yielding a mesh of high quality in less time than mapping the mesh itself. In this paper, the versatility and robustness of the method was verified by processing four datasets. The method was found to be robust enough to cope with the variability of bony surface size, spatial position and geometry, producing building block structures that generated meshes comparable to those produced using building block structures that were created manually.
116

Displaced intracapsular neck of femur fractures: dislocation rate after total hip arthroplasty

Shituleni, Sibasthiaan Gometomab January 2015 (has links)
Includes bibliographical references / Background: Dislocation is one of the most common orthopaedic complications after primary total hip arthroplasty (THA). The reported dislocation rate in elective THR is 5 - 8%. This number increases up to 22% for THA done for neck of femur fractures. Larger femoral head sizes increase the head-neck ratio and range of motion before impingement, therefore reducing the dislocation rate. Due to the reported increase in dislocation for trauma, some surgeons prefer to do a hemi-arthroplasty or open reduction and internal fixation (ORIF). Methods: A retrospective review of all THA done for neck of femur fractures during 2006 - 2012 was undertaken at a large referral hospital. Records were reviewed for patient related and surgical risk factors. We excluded all pathological fractures, extra-capsular fractures and failed ORIF. Results: A total of 96 cases were identified as suitable for analysis. Average age at surgery was 73.2 years (range 30 - 81). Delay to surgery was 5.3 days (range 1 - 63). Average follow up period was 18.3 months (range 3 months - 4.3years). Four patients (4.3%) had a confirmed dislocation. The four patients who had confirmed dislocation had the following characteristics, 28 mm femoral head size, age over 60 years, 2 posterior approaches and 3 females, although not statistically significant. Conclusion: The outcomes of THR in patients with neck of femur fractures can be favourable and provide good long-term prosthesis survival. We report on low dislocation rate post total hip replacement for intra-capsular neck of femur fractures.
117

Patienters upplevelse av trygghet i samband med regional anestesi vid elektiv ortopedisk dagkirurgi / Patients’ experiences of feeling safe when undergoing elective orthopaedic day surgery in regional anaesthesia

Häggling, Melinda, Forsberg, Anneli January 2021 (has links)
Bakgrund: Förtroende, omhändertagande, närvaro och kunskap är viktiga faktorer hos sjuksköterskan för att patienten skall känna trygghet. Det opereras dagligen hundratals patienter med elektiv ortopedisk dagkirurgi i regional anestesi i Sverige. För dessa patienter spelar anestesisjuksköterskan en viktig roll under den perioperativa processen. Oro och ångest hos patienten inför operation är vanligt förekommande, vilket kan leda till en försämrad återhämtning. Ortopediska patienter upplever dessutom sämre postoperativ återhämtning jämfört med andra patientkategorier. Det är därför av stor vikt att undersöka patientens perioperativa upplevelse av trygghet för att få en större förståelse kring vilka faktorer som kan påverka patientens trygghet och därmed postoperativa återhämtning. Syfte: Syftet med denna studie var att undersöka patienters upplevelse av trygghet i samband med ortopedisk elektiv dagkirurgi i regional anestesi. Metod: En kvantitativ icke-experimentell enkätstudie har genomförts. Patienter över 18 år som genomgått ett elektivt ortopediskt ingrepp i regional anestesi under dagkirurgisk vård inkluderades. Patienterna valdes ut från tre sjukhus i norra Sverige. Konsekutivt urval användes, vilket resulterade i 132 analyserade enkäter. På grund av icke normalfördelat data användes Mann-Whitneys U-test, Kruskall-Wallis och Spearmans korrelationstest. Resultat: Patienter upplever trygghet under den perioperativa processen och personalen spelar en viktig roll i huruvida patienten upplever trygghet. Om patienten upplever ångest påverkar detta upplevelsen av trygghet negativt. Patienter med hög utbildningsnivå kände sig mindre trygga under operationen jämfört med patienter med lägre nivå av utbildning. Slutsats: Patienterna upplever trygghet i samband med perioperativ omvårdnad och patientens upplevelse av trygghet påverkas av faktorer som vi i personalen har stor möjlighet att påverka. Bland annat spelar kommunikation, information, bemötande och attityd en viktig roll.
118

Intimate Partner Violence in Orthopaedic Surgery: Lessons Learned and Future Directions

Madden, Kim 29 September 2014 (has links)
The overarching theme of this thesis is to discuss the research to date on intimate partner violence (IPV) in orthopaedic surgery and to begin to study selected issues that have been understudied in orthopaedic surgery and IPV. This thesis outlines the current state of knowledge in the field of IPV and orthopaedic surgery and provides some insight into three selected “emerging issues” in the field which warrant future research including: education of orthopaedic surgeons and residents to reduce barriers and improve perceptions; IPV perpetrators; and outcomes for victims of IPV. The findings demonstrate that a short course on IPV for orthopaedic trainees led to an improvement and retention of knowledge three months after the course. IPV education should be integrated into training programs for orthopaedic surgeons. Our systematic review on IPV perpetrator factors indicates that using alcohol or drugs, experiencing child abuse, witnessing interparental aggression, low socioeconomic status, and psychological conditions like depression and anxiety were commonly associated with IPV perpetration. Perpetrator treatment programs should take into consideration modifiable and preventable factors that are associated with IPV perpetration. This thesis proposes a pilot prospective cohort study as the first step toward determining how experiences of IPV affect orthopaedic outcomes such as injury-related complications. The proposed study will determine feasibility and assist in the development a larger-scale multinational prospective cohort study that will engage health care professionals from around the world to increase awareness of how IPV affects patients’ musculoskeletal outcomes. In the past decade, the field of orthopaedic surgery has become more aware of the issue of IPV, but there are many questions that remain. Future research into the above issues will be an excellent first step to fully understanding the issue of IPV in orthopaedic patients, and may lead to improved support of victims of IPV in the future. / Thesis / Master of Science (MSc)
119

In-vitro Biomechanical Evaluation of Multiple Freeze-Thaw Cycles on 3D Kinematics of Human Cadaveric Lumbar Spine

Uppuganti, Sasidhar 26 August 2010 (has links)
No description available.
120

Health Research Methodology in Spine Surgery

Evaniew, Nathan M January 2016 (has links)
Symptomatic spinal disorders affect a large proportion of the population and are associated with substantial morbidity, social burden, and economic impact. Spine surgery interventions can provide excellent results in carefully selected patients whose symptoms fail to improve with non-operative management, but an evidence-based approach is paramount to optimize outcomes and rigorous standards of health research methodology are critical to avoid misleading conclusions. This thesis aimed to investigate and apply modern innovations in health research methodology to the field of spine surgery. It consists of seven chapters divided between three sections: randomized controlled trials, observational studies, and systematic reviews and meta-analyses. By applying the findings of each chapter, clinicians, researchers, and other evidence users can advance the credibility of future research and enhance the care of patients with spinal disorders. / Thesis / Doctor of Philosophy (PhD)

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