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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

電針夾背脊穴治療腰椎間盤突出症的研究進展

邵帥, 13 June 2015 (has links)
電針夾脊穴治療腰椎間盤突出症的研究進展 摘要:筆者通過對近10年來關於電針夾脊穴治療腰椎問盤突出症的研究132篇,其中有49篇是對於電針夾脊穴治療腰椎間盤突出症的有效性觀察﹔有67篇論述電針夾脊穴聯合其他治療方法的臨床觀察﹔有16篇為專門討論電針夾脊穴對治療腰間盤突出的機理的探討﹔通過對文獻的整理發現目前研究者的研究主要集中在幾個問題方面,一是電針夾脊穴治療腰椎間盤突出症的有效性觀察,目前電針夾脊穴對於腰椎問盤突出症的鎮痛效應經筆者整理,各文獻治療組鎮痛的即時起效時間為3.5-4min ,而對照組在12-13.5 min之間。治癒率治療組平均在80-90%之間,對照組在65-90%之間﹔二是電針夾脊穴的方法如選穴、針刺方法及波形、頻率等參數的運用。在筆者所搜集的文獻中,採用疏密波的文獻占48%,採用連續波(疏波)的占52%,波形的應用各有其治療特色。電針頻率色選擇,各研究者通過大量的實驗,得出高頻和低頻的有效結合對腰椎間盤突出症的治療其有較好的效果﹔三是電針夾脊穴聯合其他方法治療腰椎間盤突出症。如電針夾脊穴聯合牽引治療、電針夾脊穴聯合穴位注射治療、電針夾脊穴聯合正骨推拿治療、電針夾脊穴聯合重要薰蒸治療等,臨床上都取得了良好的效果。四是電針夾脊穴治療的作用機制,包括圍繞中醫理論指導下的機制與現代醫學的生化機制。 關鍵字:電針夾脊穴 腰椎問盤突出 電針參數
112

Desenvolvimento de dispositivos para realização de testes in vitro em coluna vertebral /

Lemos, Felipe Fernandes. January 2006 (has links)
Orientador: José Elias Tomazini / Banca: Mauro Hugo Mathias / Banca: Luiz Carlos de Queiroz / Resumo: Para melhor entender os mecanismos degenerativos da coluna vertebral e avaliar o melhor método para seu tratamento é necessário que se conheça o comportamento dos diversos componentes das articulações intervertebrais. Com isso, torna-se essencial o desenvolvimento de dispositivos capazes de simular as condições fisiológicas de movimentos e cargas a fim de realizar testes in vitro que fornecerão dados para posteriormente serem testados in vivo. O objetivo deste trabalho é o desenvolvimento de dispositivos para a realização de testes in vitro com coluna vertebral. Estes dispositivos constam de uma máquina capaz de simular o movimento de flexão-extensão, pré-cargas axiais e a angulação pélvica, e uma lâmina de extensometria para captar as deformações dos tecidos testados. Foram realizados experimentos com discos invertebrais suínos a fim de avaliar a eficiência dos dispositivos. Realizaram-se dois experimentos usando os dispositivos desenvolvidos e um experimento na máquina universal de ensaios. Como resultado obteve-se valores de propriedades mecânicas coerentes com a literatura e o disco intervertebral comportando-se como um material viscoelástico. Outro ponto importante foi a obtenção da pressão intradiscal aproximada relacionando-a com o deslocamento angular da coluna. Conclui-se que os dispositivos apresentaram funcionamento satisfatório, abrindo perspectivas para outros estudos. / Abstract: The best way to understand the degenerative mechanisms of the vertebral column and to evaluate appropriated methods for its treatment it is necessary to know the behavior of the diverse components of the intervertebral joints. So, it becomes essential to simulate the physiological conditions of movements and loads in order to carry through test in vitro that they will supply datas to be tested in vivo. The objective of this study is the development of devices of low cont for the accomplishment of tests in vitro with spine. These devices consist of a machine capable to simulate the movement of flexion-extension, daily pay-loads and the pelvic inclination, and an extensometry blade to catch the deformations of tested structures. POrcine had been carried through experiments with intervertebral discs in order to evaluate the efficiency od the devices. Two experiments had been become fullfilled using the developed devices and an experiment in the universal test machine. As result we got values of coherent mechanical properties with literature and the intervertebral disc behaving as a viscoelastic material. Another important point was the attainment of the intradiscal pressure approached relating it with the angular displacement of the spine. It is concluded that the devices had presented satisfactory functioning, opening perspective for other studies. / Mestre
113

Magnetic resonance imaging of the intervertebral disc:post-traumatic findings and the value of diffusion-weighted MR imaging

Kerttula, L. (Liisa) 18 September 2001 (has links)
Abstract Magnetic resonance imaging (MRI) provides important information about structural and biochemical changes in organs. MRI is also an effective imaging method for the evaluation of spinal disorders. However, many of its potential applications - particularly diffusion imaging - have not yet been thoroughly explored. The purpose of this study was to determine the MRI-detectable changes in the intervertebral disc after trauma and to test the feasibility of diffusion-weighted MR imaging of the intervertebral discs. A minipig model was used in the experimental study to determine the MRI changes in the intervertebral disc after peripheral annular lesions in different time frames. Three of eight discs with experimental annular lesions had a normal annular appearance in MRI. Annular lesions, when detectable, were manifested as a bulging of the disc or as a high-intensity zone (HIZ) inside the annulus. Either the signal intensity or the area of bright signal intensity in the nucleus had nearly always decreased after one month, but they were still detectable even in cases where no signs of annular trauma could be seen in the MR images. The histology of HIZ is presented for the first time: clusters of nuclear cells and disorganized granulation tissue with capillaries were detected in the HIZ area. Fourteen patients 8 to 21 years of age with histories of vertebral fracture at least one year previously and 14 asymptomatic healthy control subjects 8 to 22 years of age were studied by MRI. In these young people a vertebral fracture, especially with end-plate injury, proved to be a notable risk factor for initiating disc degeneration. The apparent diffusion coefficients (ADCs) of the thoracolumbar intervertebral discs were determined in three orthogonal directions in 18 healthy young volunteers aged 8-22 years. The ADCs were also determined in 10 young patients with previous vertebral fractures, and clear decreases were found in the ADCx and ADCy directions, but in the ADCz direction values had not changed significantly as compared to the values in the controls. The most marked changes were observed in the degenerated discs, followed by those in the discs with a normal signal intensity adjacent to the primary trauma area. Diffusion-weighted MR imaging affords a useful tool for evaluating disc diseases in the early phases. Additionally, 37 adult volunteers without back symptoms were studied by MRI and by magnetic resonance angiography (MRA) and it was found that the status of the lumbar arteries significantly explained the diffusion values in the lumbar intervertebral discs. The correlation between disc degeneration and diffusion was mostly linear, but not significant.
114

Proton NMR studies of human lumbar intervertebral discs

Rind, Teresa January 1990 (has links)
Problems with the low back resulting from diseases of the lumbar disc account for much human suffering and medical expense. Through early identification of changes in the disc, Magnetic Resonance Imaging offers a potential method for recognition of those at risk of low back trouble. An understanding of the chemical and structural basis of the MR image will therefore be of great help in understanding the degenerative mechanism itself. With this in mind, NMR studies of human intervertebral discs were performed to extract data that could be correlated with different stages of degeneration. In vitro samples of anulus fibrosus and nucleus pulposus of grades II and IV discs were examined. The Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence was used to obtain T₂ relaxation data, which were analysed with a non-negative least squares algorithm and presented as a continuous spectrum of exponentials. An inversion-recovery sequence was used to obtain T₁ data which were analysed with the same algorithm, then presented as a discrete exponential spectrum. The same procedures were used to produce relaxation times from samples of isolated disc collagen and proteoglycan. Also, T₂ relaxation data were obtained with a twelve-echo CPMG imaging sequence from healthy volunteers, and these data analysed with the same procedure used for in vitro data. In vivo and in vitro results were compared and found to agree in terms of the T₂ relaxation values. Most change between grades occurred in the nucleus, where both T₁ and T₂ values decreased from grade II to grade IV. The results of the proteoglycan and collagen studies support the theory that structure, not chemical composition, is responsible for the observed changes in relaxation times. Based on estimates of the percentages of protons in the nucleus due to water, proteoglycan and collagen, tentative assignments were made to the components of the T₂ spectra for grades II and IV nucleus, and these were supported by the results of all parts of the study. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
115

Estudo da classificação morfopatologica proposta por Landim para a estenose lombar

Pasqualini, Wagner, 1960- 03 August 2018 (has links)
Orientador: Elcio Landim / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-03T15:28:41Z (GMT). No. of bitstreams: 1 Pasqualini_Wagner_M.pdf: 1266655 bytes, checksum: d3e6214480e3e94d6ca5bbbd7373eea5 (MD5) Previous issue date: 2001 / Resumo: A síndrome da estenose do canal lombar é uma das causas mais freqüente de lombalgia e lombociatalgia, e sua incidência aumentou nas últimas décadas devido à longevidade cada vez maior da população. Foram estudados 55 exames de imagem (tomografia axial computadorizada e ressonância nuclear magnética) e, utilizando a classificação morfopatológica proposta por Landim (1999), observou-se a freqüência de cada tipo da classificação, nas diversas patologias que causam a estenose. Os resultados encontrados coincidem com a literatura existente sobre o tema, sendo a causa degenerativa para a estenose do espaço intervertebral a mais freqüente. Trata-se de uma classificação simples e útil na indicação da via de acesso cirúrgica, associada ou não à artrodese, quando o tratamento cirúrgico estiver indicado / Abstract: The syndrome of the lumbar canal stenosis is one of the most frequent causes of back pain and radicular pain, having increased its occurrences um the past decades due to the also increased longevity of the population. A total of 55 image exams (computerized axial tomography and M.R.I.) have been studied, using Landim morphopathological classification, and the frequency of each kind of classification in the various pathologies has been observed. The results of the study coincide with the availabre literature, showing the degenerative cause as the most frequent one in the lumbar canal stenosis. We consider LANDIM classification simple and very useful as an index for surgical treatment / Mestrado / Cirurgia / Mestre em Cirurgia
116

Design and Validation of a Complex Loading Whole Spinal Segment Bioreactor

Beatty, Amanda Marie 01 October 2015 (has links) (PDF)
Intervertebral disc (IVD) degeneration is a prevalent health problem that is highly linked to back pain. To understand the disease and tissue response to therapies, ex-vivo whole IVD organ culture systems have recently been introduced. The goal of this study was to develop and validate a whole spinal segment culturing system that loads the disc in complex loading similar to the in-vivo condition, while preserving the adjacent endplates and vertebral bodies. The complex loading applied to the spinal segment was achieved with three pneumatic cylinders. The pneumatic cylinders were rigidly attached to two triangular alumni plates at each corner, comprising the loading mechanism. By extending or compressing the pneumatic cylinders, three modes of loading were achieved: flexion-extension, bi-lateral bending, and cyclic compression. The cylinders were controlled via microcontroller, and the entire system was fully automated. The culture container, which housed the spinal segment during culturing, was a flexible silicone container with an aluminum base and lid. The culture container attached to the loading mechanism allows for loading of the spinal segment. It had a vent attached to the aluminum lid that allowed for gas exchange in the system. The dynamic bioreactor was able to achieve physiologic loading conditions with 100 N of applied compression and approximately 2-4 N-m of applied torque. The function of the bioreactor was validated through testing of bovine caudal IVDs with intact endplates and vertebral bodies that were isolated within 2 hours of death and cultured for 14 days under a diurnal cycle. The resulting IVD cell viability following 14 days of loading was approximately 43% and 20% for the nucleus pulposus and annulus fibrosus respectively, which was significantly higher than the unloaded controls. The loading system accurately mimicked flexion-extension, bi-lateral bending, and compression motions seen during daily activities. Results indicate that this complex dynamic bioreactor may be appropriate for extended pre-clinical testing of vertebral mounted spinal devices and therapies.
117

A Proteolytic Process to Simulate the Mechanics of Disc Dengeration in Bovine Cadaveric Tissue

Bishop, Timothy A. 16 March 2011 (has links) (PDF)
Purpose. The present work hypothesized that proteolytic dissolution of intervertebral discs could induce biomechanical change comparable to the change observed in natural disc degeneration. A method to do such could be utilized for in vitro research where intersample differences in geometry and chemical makeup render it difficult to compare and aggregate results into generalized conclusions. Methods. Forty-one bovine coccygeal intervertebral discs were isolated with individual functional spinal units. Samples were loaded in three modes: compression/tension, flexion/extension, and axial rotation. The anulus fibrosus of each disc was injected with 200µl trypsin or fetal bovine serum (control) and incubated for an allotted period: 30 minute, 60 minutes, or 180 minutes. Mechanical loading was repeated and the load-displacement responses before and after treatment were compared as were the differences between each time group. Results. Significant change was observed in the discs' total range (stiffness), low range (laxity), and hysteresis. Changes in load-displacement response were observed to be correlated with both treatment and time. Conclusions. Enzymatic degeneration of intervertebral discs shows promise as a means to further understanding of disc mechanics in varying levels of degeneration. In virtually all cases, the trypsinized discs exhibited the increased joint laxity and decreased stiffness that is associated with early stage, natural disc degeneration.
118

Auxetic Spinal Implants: Consideration of Negative Poisson's Ratio in the Design of an Artificial Intervertebral Disc

Baker, Carrie E. 24 May 2011 (has links)
No description available.
119

AUTOMATED VERTEBRA SEGMENTATION AND QUANTIFICATION ALGORITHM OF WHOLE SPINE MR IMAGES

ZHONG, JIA 07 October 2004 (has links)
No description available.
120

Magnetization Transfer and Diffusion Tensor Imaging in Dogs with Intervertebral Disc Herniation

Shinn, Richard Levon 14 July 2020 (has links)
Background: Quantitative imaging surrogates of myelin and axonal integrity using magnetization transfer and diffusion tensor imaging may provide beneficial prognostic details on long-term post-surgical recovery in dogs with spinal cord injury (SCI) secondary to intervertebral disc herniation (IVDH). Hypothesis: Magnetization transfer ratio (MTR), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), and fractional anisotropy (FA) will be significantly different in patients with a successful outcome compared to patients with an unsuccessful outcome. Animals: 61 dogs with SCI secondary to IVDH were included in the final analysis. All dogs had to undergo surgical correction for SCI secondary to IVDH and be followed out for 12 weeks. Methods: Prospective cohort study. MTR, MD, AD, RD, and FA were calculated in dogs with SCI secondary to IVDH. A Wilcoxon signed-rank test was used to compare MTR, MD, AD, RD, and FA values between patients with a successful outcome and patients with an unsuccessful outcome. Statistical significance was set at p<0.05. For quantitative imaging surrogates with a significant relationship with outcome, a receiver operator characteristic (ROC) curve analysis was performed and the sensitivity and specificity for predicting successful outcome. Results: MTR (p=0.0013) was significantly lower in patients with a successful outcome compared to patients with an unsuccessful outcome. FA (p=0.435) was not significantly between groups. MD (p=0.0006), AD (p=0.0008) and RD (p=0.0002) were significantly higher in patients with a successful outcome compared to patients with an unsuccessful outcome. ROC curves were performed for MTR, AD and RD. If MTR was ≤ 53, AD ≥ 1.7 × 10-3mm2/s or RD ≥ 0.37 × 10-3 mm2/s, this resulted in a sensitivity of 96.3% and specificity of 100 in predicting a successful outcome. Conclusion and clinical relevance: MTR, MD, AD, and RD were helpful in predicting successful outcome in canine patients with surgically treated SCI secondary to IVDH. A larger cohort is needed for further evaluation. / Master of Science / Background: Certain magnetic resonance imaging (MRI) techniques can provide information about the severity of spinal cord injury. The information obtained from these MRI techniques can be helpful in predicting prognosis in dogs with intervertebral disc disease (IVDD). Hypothesis: We hypothesized that the measurements obtained from these MRI techniques would be able to predict the patients who would be able to walk following surgery (good long-term outcome), versus the patients who did not regain the ability to walk following surgery (poor long-term outcome). Animals: 62 MRIs were performed on dogs with IVDD in our study and were followed out for 12 weeks following surgery to assess long-term outcome. Results: Of the 5 MRI techniques investigated, 4 of the techniques were found to be helpful in predicted long-term outcome. When these techniques were combined, the ability to predict long-term outcome improved. Using the combined technique, all 53 patients predicted to have a good long-term had a good long-term outcome. For patients with a poor long-term outcome, 9 were predicted to have a poor long-term outcome, but only 7 patients had a poor long-term outcome. Conclusion and clinical relevance: MRI can be helpful in predicting long-term outcome in dogs with IVDD following surgery. A larger population of dogs is needed for further evaluation.

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