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排序方式: 共有1096条查询结果,搜索用时 15 毫秒
991.
Sidney Glanz M.D. David H. Gordon Navin Shah Bernard Jaffe Randall Griepp 《Cardiovascular and interventional radiology》1982,5(6):292-295
Two unusual manifestations of aortic dissection, rupture into the main pulmonary artery and rupture into the inferior vena
cava, are presented. The latter complication has not been reported previously in the literature. The value of inferior vena
caval oximetry to delineate the site of fistulous communication is stressed. 相似文献
992.
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994.
Preeti Singh M.D. Rajarshi Dutta M.B.B.S. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2009,26(4):478-480
We describe the usefulness of three-dimensional transthoracic echocardiography (3D TTE) in the assessment of bicuspid aortic valve morphology in an adult patient with no stenosis but severe aortic regurgitation . 相似文献
995.
Medulloepithelioma of the optic nerve is extremely rare and can simulate an optic nerve glioma. We report a histopathologically proven medulloepithelioma in a 3-year-old child with computer tomographic (CT) and magnetic resonance imaging (MRI) features. 相似文献
996.
Navin C. Nanda M.D. Deepak Joshi M.D. Hari Prakash Diddi M.B.B.S. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(2):219-224
We report an elderly patient presenting with a stroke and also hemolytic anemia secondary to mitral and tricuspid valve repair 3 years earlier, in whom two‐dimensional transesophageal echocardiography (2DTEE) suspected a fistula into the pulmonary artery (APAF) from the posterior wall of the aortic arch. For further assessment, two‐dimensional transthoracic echocardiography (2DTTE) and live/real time three‐dimensional transthoracic echocardiography (3DTTE) were performed. 2DTTE showed findings similar to 2DTEE. Color Doppler guided continuous‐wave Doppler showed continuous flow throughout the cardiac cycle with systolic preponderance across the fistula with a small peak pressure gradient of 22 mmHg. Sequential systematic cropping of the 3D datasets obtained from 3DTTE confirmed that the flow signals originated from the posterior wall of the aortic arch and not the lumen. Thus, 3DTTE served to increase the confidence level that the fistula most likely originated from a vasum vasi in the wall of the aortic arch. To our knowledge, this type of fistula has not been reported previously. Fistulas from the aortic lumen to the pulmonary artery are also rare and so far only 24 cases have been reported in the literature. These are also reviewed by us. 相似文献
997.
Jonathan M. Collier Navin Vig Douglas Hammond 《The British journal of oral & maxillofacial surgery》2010
Publications are important for all surgeons, including those practising oral and maxillofacial surgery (OMFS). The results of relevant research are usually presented at the annual scientific meetings of the British Association of Oral and Maxillofacial Surgeons (BAOMS). The aim of this study was to find out how many abstracts that were accepted for presentation at the BAOMS go on to be published. Lists of abstracts accepted at BAOMS meetings 2002–2006 were obtained, and a thorough search was made for each article using the web-based search engine PubMed. Related publications were recorded. A total of 623 abstracts were accepted, of which only 147 (24%) resulted in peer-reviewed publication. Compared with clinical studies, scientific research was in the minority, but was more likely to appear in print and in journals with higher impact factors. Units with senior academic input had better records of publication. Currently only a small fraction of studies deemed worthy of presentation at the BAOMS become publications. This conversion from presentation to print is facilitated by strong academic support. Exposing trainees in OMFS training posts to basic research training might improve their ability to publish. 相似文献
998.
Nilda Espínola‐Zavaleta M.D. Fahad M. Iqbal M.D. Navin C. Nanda M.D. Eduardo Enríquez‐Rodríguez M.D. Luís M. Amezcua‐Guerra M.D. Rafael Bojalil‐Parra M.D. Ph.D. Pedro A. Reyes M.D. María Elena Soto M.D. M.Sc. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(8):923-930
Background: The cardiovascular manifestations of Marfan syndrome (MFS) are the main causes of morbidity and mortality. This study describes the clinical and echocardiographic findings in a Mestizo‐Mexican population affected by the disease. Methods: A total of 166 patients previously diagnosed with MFS were recruited for the study, 114 of them underwent complete clinical history, with emphasis on Ghent nosology criteria, and transthoracic echocardiography, with 68 patients also undergoing transesophageal study. Results: Major cardiovascular criteria from the Ghent nosology predominated in adults (P < 0.0001), minor criteria in children (P = 0.007). Among pediatric patients, 83% had a New York Heart Association (NYHA) functional class of I; however, 64% of the adult patients had an NYHA class ≥II, (P < 0.0001). Corrected aortic echocardiographic measurements of both groups demonstrated statistically significant differences. Children had a greater prevalence of mitral valve prolapse, while adults more frequently presented with aortic complications. Seven patients died during follow‐up from aortic complications, one child and six adults. Conclusions: Based on the data, we can conclude that MFS in the Mestizo‐Mexican population has a distinctly different clinical pattern in children and adults, and a graver prognosis in adults. Adult patients with MFS are significantly more likely, than children, to have aortic dilation, aortic aneurysm, aortic regurgitation, aneurysm rupture, aortic dissection, and fatal outcome. Children with MFS are more likely, than adults, to present with asymptomatic mitral and tricuspid prolapse and mitral valve regurgitation. (Echocardiography 2010;27:923‐930) 相似文献
999.
Purpose: The purpose of this study was to determine if an optimal knee flexion angle existed that would minimize the risk of neurovascular injury from the passage of transtibial hardware during posterior cruciate ligament (PCL) reconstruction. Type of Study: Cadaveric. Materials and Methods: Fourteen fresh-frozen cadaveric knees were mounted in a Plexiglas apparatus that could be set at 5 different knee flexion angles (0°, 45°, 60°, 90°, and 100°) while joint distention was maintained. Each knee underwent magnetic resonance imaging in the axial and sagittal planes at each of the 5 flexion angles to determine the distance between the PCL tibial insertion and popliteal artery. Results: The mean distance, over all 5 flexion angles, between the PCL insertion and the popliteal artery in the axial plane was 7.6 mm, whereas the mean distance in the sagittal plane was 7.2 mm. There was a significant increase in distance with progressive flexion in both planes. Maximum mean distances were noted at 100° of flexion in both the axial (9.9 mm) and sagittal (9.3 mm) planes. An artificial line mimicking the path of a transtibial drill passed through the popliteal artery in 10 of 10 cases at the 0°, 45°, 60°, and 90° angles, and in 6 of 10 cases at the 100° angle. Conclusions: The results of this study suggest that increasing knee flexion reduces, but does not completely eliminate, the risk of arterial injury during arthroscopic PCL reconstruction. 相似文献
1000.
Navin Elango Brendan G. Hunt Michael A. D. Goodisman Soojin V. Yi 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(27):11206-11211
The recent, unexpected discovery of a functional DNA methylation system in the genome of the social bee Apis mellifera underscores the potential importance of DNA methylation in invertebrates. The extent of genomic DNA methylation and its role in A. mellifera remain unknown, however. Here we show that genes in A. mellifera can be divided into 2 distinct classes, one with low-CpG dinucleotide content and the other with high-CpG dinucleotide content. This dichotomy is explained by the gradual depletion of CpG dinucleotides, a well-known consequence of DNA methylation. The loss of CpG dinucleotides associated with DNA methylation also may explain the unusual mutational patterns seen in A. mellifera that lead to AT-rich regions of the genome. A detailed investigation of this dichotomy implicates DNA methylation in A. mellifera development. High-CpG genes, which are predicted to be hypomethylated in germlines, are enriched with functions associated with developmental processes, whereas low-CpG genes, predicted to be hypermethylated in germlines, are enriched with functions associated with basic biological processes. Furthermore, genes more highly expressed in one caste than another are overrepresented among high-CpG genes. Our results highlight the potential significance of epigenetic modifications, such as DNA methylation, in developmental processes in social insects. In particular, the pervasiveness of DNA methylation in the genome of A. mellifera provides fertile ground for future studies of phenotypic plasticity and genomic imprinting. 相似文献