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991.
Mariah Madigan BA Sarah McIsaac MD Avinash Garg MD Abdul Alqahtani MD Andreas Kumar MD Rony Atoui MD 《Journal of cardiac surgery》2020,35(1):204-206
We report a rare case of a 44-year-old male who underwent a diagnostic coronary angiogram following a non-ST elevation myocardial infarction complicated by an aortic valve leaflet tear requiring surgical intervention. Routine transthoracic echocardiogram demonstrated a mobile echogenic structure prolapsing into the left ventricular outflow tract. An intraoperative transesophageal echocardiogram confirmed that the structure originated from the ventricular side of left coronary cusp, causing malcoaptation between left and right coronary cusps, and subsequent moderate to severe aortic regurgitation. 相似文献
992.
Vineeta Ojha MD Sh Chandrashekhara DM Amarinder Singh Malhi DM Sanjeev Kumar MD 《Journal of cardiac surgery》2020,35(6):1340-1341
We present images from computed tomography angiography in a 40-year-old female with a calcified pseudo-aneurysm in her left coronary artery, who had previously undergone repair of tetralogy of Fallot. 相似文献
993.
Niraj Nirmal Pandey DM Mumun Sinha MD Sanjeev Kumar MD 《Journal of cardiac surgery》2020,35(7):1624-1625
We present a case of type B aortic dissection with a rare aortic arch branching variation whereby two separate brachiocephalic trunks arise from the arch. This case also highlights the potential implications of this variant in the management of thoracic aortic dissections and aneurysms. 相似文献
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995.
Biswajit Kumar Biswas Sutapa Dey Anindya Chakrabarty Arghya Laha Tapan Kumar Mandal Laxmikanta Karmakar Debajyoti Das 《Artificial organs》2020,44(11):E494-E508
Cartilage is avascular with limited to no regenerative capacity, so its loss could be a challenge for reconstructive surgery. Current treatment options for damaged cartilage are also limited. In this aspect there is a tremendous need to develop an ideal cartilage-mimicking biomaterial that could repair maxillofacial defects. Considering this fact in this study we have prepared twelve silicone-based materials (using Silicone 40, 60, and 80) reinforced with hydroxyapatite, tri-calcium phosphate, and titanium dioxide which itself has proven their efficacy in several studies and able to complement the shortcomings of using silicones. Among the mechanical properties (Young’s modulus, tensile strength, percent elongation, and hardness), hardness of Silicone-40 showed similarities with goat ear (P > .05). Silicone peaks have been detected in FTIR. Both AFM morphology and SEM images of the samples confirmed more roughed surfaces. All the materials were nonhemolytic in hemocompatibility tests, but among the twelve materials S2, S3, S5, and S6 showed the least hemolysis. For all tested bacterial strains, adherence was lower on each material than that grown on the plain industrial silicone material which was used as a positive control. S2, S3, S5, and S6 samples were selected as the best based on mechanical characterizations, surface characterizations, in vitro hemocompatibility tests and bacterial adherence activity. So, outcomes of this present study would be promising when developing ideal cartilage-mimicking biocomposites and their emerging applications to treat maxillofacial defects due to cartilage damage. 相似文献
996.
Varalakshmi Boreddy Kiranmyai V. S. Aparna Bitla Ram Rapur Rao P. V. L. N. Srinivas Kumar Vishnubotla Siva 《International urology and nephrology》2020,52(5):917-921
International Urology and Nephrology - Osteopontin (OPN) is evolving as a novel biomarker of injury, overall survival and renal outcome in critically ill patients with acute kidney injury (AKI),... 相似文献
997.
998.
Ranjay Chakraborty PhD BS Optometry Lisa A Ostrin PhD OD FAAO Alexandra Benavente-Perez PhD MS BS Optometry Pavan Kumar Verkicharla PhD BS Optometry 《Clinical & experimental optometry》2020,103(1):55-67
Our current understanding of emmetropisation and myopia development has evolved from decades of work in various animal models, including chicks, non-human primates, tree shrews, guinea pigs, and mice. Extensive research on optical, biochemical, and environmental mechanisms contributing to refractive error development in animal models has provided insights into eye growth in humans. Importantly, animal models have taught us that eye growth is locally controlled within the eye, and can be influenced by the visual environment. This review will focus on information gained from animal studies regarding the role of optical mechanisms in guiding eye growth, and how these investigations have inspired studies in humans. We will first discuss how researchers came to understand that emmetropisation is guided by visual feedback, and how this can be manipulated by form-deprivation and lens-induced defocus to induce refractive errors in animal models. We will then discuss various aspects of accommodation that have been implicated in refractive error development, including accommodative microfluctuations and accommodative lag. Next, the impact of higher order aberrations and peripheral defocus will be discussed. Lastly, recent evidence suggesting that the spectral and temporal properties of light influence eye growth, and how this might be leveraged to treat myopia in children, will be presented. Taken together, these findings from animal models have significantly advanced our knowledge about the optical mechanisms contributing to eye growth in humans, and will continue to contribute to the development of novel and effective treatment options for slowing myopia progression in children. 相似文献
999.