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Doppler ultrasound is a useful investigatory tool in the field of obstetrics & gynaecology陳鳳儀, Chan, Fung-yee. January 1995 (has links)
published_or_final_version / Medicine / Master / Doctor of Medicine
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Sonographic features of fetuses with homozygous [alpha]-thalassaemia-1during early pregnancy林勇行, Lam, Yung-hang. January 2001 (has links)
published_or_final_version / Medicine / Master / Doctor of Medicine
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Deconvolution of three-dimensional medical ultrasoundGomersall, William Henry January 2011 (has links)
No description available.
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The efficacy of a combined risk factor and quantitative ultrasound osteoporosis screening toolKruckenberg, Micaela A. January 2009 (has links)
The primary purpose of this research study was to cross-validate the risk factors in the Osteoporosis Risk Assessment by Composite Linear Estimate [ORACLE] as a screening tool in a population of healthy U.S. women at various menopausal stages. The secondary purpose of this study was to evaluate the potential use of physical activity history and relevant osteoporosis risk factors to effectively determine current bone status for a mixed menopausal population. Third, the purpose of this study was to compare Omnisense quantitative ultrasound [QUS] and dual-energy x-ray absorptiometry [DXA] diagnostic values of osteopenia/osteoporosis based upon T- and Z-scores. Methods: Fifty-six female subjects (46.1 ± 6.3 years) in pre-, peri-, and post-menopausal stages who volunteered to participate in this study. Subjects completed an osteoporosis risk factor and physical activity history questionnaire. Subjects underwent laboratory testing comprised of distal radius quantitative ultrasound scan, dual hip and spine DXA scans, and a one week physical activity assessment. Results: Logistic regression analysis was utilized to examine the ability of the ORACLE to predict low BMD at the femoral neck and lumbar spine. There were no significant relationships
between the group of ORACLE variables and BMD status at either the femoral neck or lumbar spine. In addition, none of the individual variables (age, BMI, use of HRT therapy, previous fracture, speed of sound [SOS]) were found to be significant predictors of low BMD at the femoral neck or lumbar spine. Notably, SOS measures from the Omnisense QUS were not found to have a strong positive predictive ability, with sensitivity values between 0-20% and specificity values between 81-86% at the femoral neck and lumbar spine. When the cohort was divided into normal and overweight/obese groups, sensitivity and specificity of QUS measures was not improved in the normal BMI group compared to the overweight/obese group. The use of physical activity variables to predict low BMD revealed some relationships trending toward significance, supporting previous research. Linear regression analyses revealed that the individual accelerometry variable of moderate-vigorous non-bout activity counts at the lumbar spine approached significance as a predictor of low BMD (p = 0.081). A significant correlation (r = 0.31, p < 0.05) between steps/day and subjective measures of current weight-bearing activity support the validity of the physical activity recall method for current physical activity. Conclusions: This study found that the ORACLE risk factors were not a valid osteoporosis screening tool in a mixed menopausal population of U.S. women. Secondarily, subjective and objective physical activity measures were non-significant predictors of current low BMD, but greater levels of moderate to vigorous non-bout activity counts trend towards being a significant predictor of higher BMD at the lumbar spine. Finally, results showed that Omnisense QUS measures were not found to be significantly related to DXA measures. Key Words: bone mineral density, dual-energy x-ray absorptiometry, osteoporosis, physical activity, quantitative ultrasound. / School of Physical Education, Sport, and Exercise Science
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Real-time ultrasonic diagnostic technology for polymer injection molding processesCheng, Chin-Chi, 1970- January 2007 (has links)
Integrated high-temperature (HT) ultrasonic sensors have been developed successfully by using piezoelectric bismuth titanate and lead zirconate titanate films HT ultrasonic transducers for real-time, non-destructive, and non-intrusive diagnosis of polymer injection molding (IM) processes. The HT ultrasonic sensors can be integrated onto the barrel and/or mold of IM machine, according to the customer's requirements. These sensors can be operated up to 400°C without cooling system and ultrasonic couplant, and can be miniaturized with sufficient signal strength and signal-to-noise ratio. / The chosen IM processes are grouped to large- and small-scale 1M processes. The large-scale ones include conventional IM, co-injection molding (COIM), and fluid (gas/water) assisted injection molding (GAIM/WAIM). A filling incompleteness of 1 volume-% for IM of polycarbonate (PC) part, the core (PC) material movement and layers dimensions for COIM, the fluid motion, thickness and deformation of the hollowed high-density polyethylene (HDPE) part for GAIM/WAIM were diagnosed during processing by ultrasonic sensors and techniques developed. / The small-scale ones include IM for microfluidic device (IMMF) and micromolding (MM). The optimization of holding pressure for producing a flat polymethyl methacrylate (PMMA) part (surface roughness < 5 mum) having micro structures for IMMF, estimation of temperature of polyacetal copolymer (POM) melt in the barrel and filler concentration of nylon 66 (PA66) mixed with polyhedral oligomeric silsesquioxanes (POSS) part in the mold for MM, and evaluation of thickness variation of molded alumina ceramic powder part for MM were demonstrated. The melting stages and quality of low-density polyethylene (LDPE) in the barrel has been successfully monitored using ultrasound. The important phenomena during melting processes, such as partially melting pellets, air bubbles, melting completeness, and effects of melting temperature and rotation speed have been diagnosed by ultrasonic signatures. / These diagnostic results verify that the developed integrated HT ultrasonic sensors and techniques are capable of monitoring various IM processes to fabricate parts and products having complex formation, tiny size and micro structures, and evaluating the part quality in order to provide timely information for process optimization.
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Integrated system for ultrasonic, elasticity and photoacoustic imagingPark, Suhyun, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
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Ultrasound phased array simulations for hyperthermiaZeng, Xiaozheng. January 2008 (has links)
Thesis (PH. D.)--Michigan State University. Electrical Engineering, 2008. / Title from PDF t.p. (viewed on Sept. 8, 2009) Includes bibliographical references (p. 155-162). Also issued in print.
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Unique determination of acoustic properties from thermoacoustic data /Hickmann, Kyle Scott. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 182-187). Also available on the World Wide Web.
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Fabrication, characterization and modeling of K₃₁ piezoelectric micromachined ultrasonic transducers (pMUTs)Choi, Hongsoo, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, December 2007. / Includes bibliographical references (p. 138-148).
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Análise histopatológica de biópsia prostática guiada pelo ultrassom transretal com 10 e 12 fragmentos: ensaio clínico prospectivo controlado / Histopathological analysis of prostate biopsy guided by transrectal ultrasound with 10 and 12 fragments: prospective controlled clinical trialChambó, Renato Caretta [UNESP] 30 May 2014 (has links) (PDF)
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000807345.pdf: 707423 bytes, checksum: 205e8e0f3c0e8ad8d1ab617261b02bc6 (MD5) / Objetivo: Avaliar a utilidade do uso de 10,12 e 16 fragmentos em biópsias de próstata na positividade para câncer de próstata (CaP) bem como quanto o Antígeno Prostático Específico (PSA), volume prostático, escore de Gleason, detecção de Neoplasia Intraepitelial Prostática de Alto Grau (NIPAG) e Proliferação Atípica de Pequenos Ácinos (ASAP). Métodos: É um estudo prospectivo e controlado, realizado em uma amostra consecutiva de 354 pacientes com diferentes indicações para biópsia prostática que foram submetidos ao procedimento analisando a positividade de câncer de próstata com a coleta de 10 fragmentos (base, terço médio, ápice, face medial (zona de transição) e face látero-lateral, bilateralmente) comparando com 12 fragmentos (base, terço médio, ápice e nas regiões mais laterais da base, terço médio e ápice, bilateralmente) e o total global de 16 fragmentos. Também comparada a positividade com 10, 12 e 16 fragmentos quanto ao PSA, volume prostático, escore de Gleason, NIPAG e ASAP. Resultados: Entre os 351 pacientes selecionados para biópsia de próstata, a positividade para 10 fragmentos foi de 102 pacientes (29.06%), 12 fragmentos foi de 99 pacientes (28.21%) e 16 fragmentos foi de 107 pacientes (30.48%) (p = 0.79).Os protocolos de biópsia de próstata (10,12 e 16 fragmentos) foram comparados com o PSA estratificado, volume prostático estratificado, escore de Gleason, detecção de NIPAG e ASAP não havendo diferença entre os grupos aferidos. Conclusão: O protocolo com 10 fragmentos não apresentou diferença de positividade em relação aos protocolos de 12 e 16 fragmentos, demonstrando ser um bom método para realização de primeira biópsia / Objective: To evaluate the utility of 10,12 and 16 fragments in prostate biopsies positive for the prostate cancer (PCa) as well as the Prostate Specific Antigen (PSA), prostate volume, Gleason score, Prostatic Intraepithelial Neoplasia Detection High Grade (NIPAG) and Atypical Small Acinar Proliferation (ASAP). Methods: It is a prospective controlled study performed with a sample of 354 consecutive patients with different indications for prostate biopsy who underwent the procedure analyzing the positivity of prostate cancer with the collection of 10 cores (base, middle third, apex, medial (transition zone) and latero-lateral, bilaterally) compared with 12 cores (base, middle third, apex and in areas more lateral to the base, middle third and apex, bilaterally) and the global total of 16 cores. It also was compared the positivity with 10, 12 and 16 cores, concerning the PSA, prostate volume, Gleason score, NIPAG and ASAP. Results: Among 351 patients screened for prostate biopsy positivity to 10 cores was 102 patients (29.06%), 12 cores of 99 patients (28.21%) and 16 cores of 107 patients (30.48%) (p = 0.798). The prostate biopsy protocols (10, 12 and 16 cores) were compared with the stratified PSA, stratified prostate volume,Gleason score, detection NIPAG and ASAP, there was no statistical difference. Conclusion: The protocol with 10 cores showed no difference in positivity in relation to 10 and 16 cores protocols, proving to be a good method for performing first biopsy
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