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排序方式: 共有1638条查询结果,搜索用时 15 毫秒
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Babak Kasravi MD Cheryl L. Reid MD Byron J. Allen MD 《Journal of the American Society of Echocardiography》2004,17(12):599-1316
Coronary artery fistula is often considered to be a benign and rare congenital anomaly. It is usually an incidental finding encountered during routine cardiac catheterization. We report a case of a patient presenting with endocarditis involving a large coronary artery fistula connecting an aneurysmal circumflex coronary artery to the coronary sinus. The diagnosis was initially made by echocardiography and confirmed by cardiac catheterization. In addition, we briefly discuss the literature on management of this coronary anomaly. 相似文献
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Seth M Brown Babak Sadoughi Hernando Cuellar Ron von Jako Marvin P Fried 《Otolaryngology--head and neck surgery》2007,136(2):268-273
OBJECTIVE: One of the main limitations of image-guided surgery is that navigation relies on the use of a CT scan obtained before surgery and is unable to be updated during the procedure. A software addition has been developed to allow reconstruction of CT-like images from a series of fluoroscopic scans and integrate these into an image-guided system (GE Healthcare Surgical Navigation, Lawrence, MA). We report our initial experience with a series of patients undergoing intraoperative fluoroscopic navigation in sinus surgery. STUDY DESIGN AND SETTINGS: After institutional review board clearance, we prospectively studied 14 consecutive patients undergoing image-guided sinus surgery with the use of intraoperative fluoroscopy. RESULTS: All patients had preoperative and postoperative fluoroscopic images reconstructed into CT-like images. By the conclusion of the study, images were adequate in quality and accurate navigation was achieved. CONCLUSION: Real-time image-guided sinus surgery using fluoroscopy is feasible. Future studies will need to focus on defining the procedures that could benefit, such as tumor resection, to enhance patient safety during these operations. 相似文献
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Nir Giladi Babak Boroojerdi Amos D Korczyn David J Burn Carl E Clarke Anthony H V Schapira 《Movement disorders》2007,22(16):2398-2404
Rotigotine is a new, non-ergot dopamine agonist formulated in a transdermal delivery system. The present study was to investigate the efficacy and safety of the rotigotine transdermal patch in the treatment of early Parkinson's disease. Patients (n = 561) were randomized to rotigotine, ropinirole, or placebo. The titration period was up to 13 weeks, and there was a minimum dose-maintenance period of 24 weeks for ropinirole and 33 weeks for rotigotine. The primary endpoint was the proportion of patients with a minimum of 20% decrease in the combined Unified Parkinson's Disease Rating Scale Part II and Part III scores. The responder rate in the rotigotine group was significantly higher than in the placebo group (52% vs. 30%, P < 0.0001). Transdermal rotigotine at doses < or =8 mg/24 h did not show noninferiority to ropinirole at doses < or =24 mg/day. In a post-hoc subgroup analysis, rotigotine < or =8 mg/24 hours had a similar efficacy to ropinirole at doses < or =12 mg/day. The rotigotine transdermal patch was well tolerated. The most common adverse events were application-site reactions, nausea, and somnolence. Application-site reactions were predominantly mild or moderate in intensity. In conclusion, the rotigotine transdermal patch represents an effective and safe option for the treatment of patients with early Parkinson's disease. 相似文献
7.
Synergistic interaction of topographic features in the production of bone-like nodules on Ti surfaces by rat osteoblasts 总被引:4,自引:0,他引:4
The objective of this study was to study the responses of osteoblast-like cells to rough Titanium (Ti)-coated epoxy surfaces of differing topographic complexity. Four topographies were studied: polished (PO), coarse-blasted (CB), acid-etched (AE) and coarse-blasted+acid-etched (SLA). Rat osteoblasts were cultured on these surfaces and their morphology, thickness as well as the number and size of bone-like nodules measured. To determine cell shape and cell thickness, fluorescein-5-thiosemicarbazide was used to stain the cell components including the cell membrane, the stained cells were optically sectioned using epifluorescent microscopy and the optical sections were computationally reconstructed to obtain three-dimensional images in which cell volume and cell thickness could be determined. Similarly optical sections of bone-like nodules labeled with tetracycline were also reconstructed to determine their size. The different surface topographies were found to alter the thickness and morphology of osteoblasts cultured on these surfaces. Osteoblasts produced significantly more and larger nodules on SLA compared to other surfaces. Nevertheless and perhaps surprisingly, given the evidence in various cell populations that cell shape can affect cell differentiation, cell thickness was not directly correlated with an increase in bone-like nodule formation. Data were analyzed by factorial analysis of variance. In this way the primary effect of each surface treatment ( i.e. blasting and acid etching) could be assessed as well as their interaction. Both the acid etching and blasting processes significantly affected the number and size of bone-like nodules cultured on Ti surfaces. Moreover there were significant interaction effects indicating that surface topographic features can act synergistically to enhance bone formation. This result suggests that a useful approach to the optimization of surfaces for bone production could involve systematic investigation of combinations of processes each of which produces distinct surface topographical features. 相似文献
8.
Hao Wang Ingeborg Barisic Maria Loane Marie‐Claude Addor Linda M. Bailey Miriam Gatt Kari Klungsoyr Olatz Mokoroa Vera Nelen Amanda J. Neville Mary O'Mahony Anna Pierini Anke Rissmann Christine Verellen‐Dumoulin Hermien E.K. de Walle Awi Wiesel Katarzyna Wisniewska Lolkje T.W. de Jong‐van den Berg Helen Dolk Babak Khoshnood Ester Garne 《American journal of medical genetics. Part A》2019,179(4):595-601
We aimed to assess prevalence, birth outcome, associated anomalies and prenatal diagnosis of congenital clubfoot in Europe using data from the EUROCAT network, and to validate the recording of congenital clubfoot as a major congenital anomaly by EUROCAT registries. Cases of congenital clubfoot were included from 18 EUROCAT registries covering more than 4.8 million births in 1995–2011. Cases without chromosomal anomalies born during 2005–2009, were randomly selected for validation using a questionnaire on diagnostic details and treatment. There was 5,458 congenital clubfoot cases of which 5,056 (93%) were liveborn infants. Total prevalence of congenital clubfoot was 1.13 per 1,000 births (95% CI 1.10–1.16). Prevalence of congenital clubfoot without chromosomal anomaly was 1.08 per 1,000 births (95% CI 1.05–1.11) and prevalence of isolated congenital clubfoot was 0.92 per 1,000 births (95% CI 0.90–0.95), both with decreasing trends over time and large variations in prevalence by registry. The majority of cases were isolated congenital clubfoot (82%) and 11% had associated major congenital anomalies. Prenatal detection rate of isolated congenital clubfoot was 22% and increased over time. Among 301 validated congenital clubfoot cases, diagnosis was confirmed for 286 (95%). In conclusion, this large population‐based study found a decreasing trend of congenital clubfoot in Europe after 1999–2002, an increasing prenatal detection rate, and a high standard of coding of congenital clubfoot in EUROCAT. 相似文献
9.
Babak S. Jahromi Yasuo Aihara Jinglu Ai Zhen-Du Zhang George Weyer Elena Nikitina Reza Yassari Khaled M. Houamed R. Loch Macdonald 《Neuroscience letters》2008
The pathogenesis of cerebral vasospasm after subarachnoid haemorrhage (SAH) involves sustained contraction of arterial smooth muscle cells that is maximal 6–8 days after SAH. We reported that function of voltage-gated K+ (KV) channels was significantly decreased during vasospasm 7 days after SAH in dogs. Since arterial constriction is regulated by membrane potential that in turn is determined predominately by K+ conductance, the compromised K+ channel dysfunction may cause vasospasm. Additional support for this hypothesis would be demonstration that K+ channel dysfunction is temporally coincident with vasospasm. To test this hypothesis, SAH was created using the double haemorrhage model in dogs and smooth muscle cells from the basilar artery, which develops vasospasm, were isolated 4 days (early vasospasm), 7 days (during vasospasm) and 21 days (after vasospasm) after SAH and studied using patch-clamp electrophysiology. We investigated the two main K+ channels (KV and large-conductance voltage/Ca2+-activated (KCa) channels). Electrophysiologic function of KCa channels was preserved at all times after SAH. In contrast, function of KV channels was significantly decreased at all times after SAH. The decrease in cell size and degree of KV channel dysfunction was maximal 7 days after SAH. The results suggest that KV channel dysfunction either only partially contributes to vasospasm after SAH or that compensatory mechanisms develop that lead to resolution of vasospasm before KV channels recover their function. 相似文献
10.
Amini-Bavil-Olyaee S Sarrami-Forooshani R Mahboudi F Sabahi F Adeli A Noorinayer B Azizi M Reza Zali M 《Journal of medical virology》2005,75(2):227-234
Hepatitis B virus (HBV) is one of the major causative agents of acute and chronic liver disease worldwide and is believed to be responsible for a million deaths annually. Eight genotypes of HBV, A to H, have been described on the basis of similarity of the complete genomes sequence. Although, it is reported that the predominant HBV genotype in the Mediterranean area and the middle east is genotype D, there are no reports on HBV genotypes prevalent in Iran. In this study, the C and S regions of HBV from 26 chronic hepatitis B Iranian patients were amplified and sequenced. Phylogenetic analysis revealed that all Iranian HBV isolates sequences were classified into genotype D with bootstrap values of 100%, 73%, and 100% (1,000 replicates each) for S, C, and preS2 regions, respectively. The mean percent intra-distance of S and C regions were 0.8% and 2.3%, respectively. The mean percent inter-distance of S and C regions between Iranians and genotype D isolates were 1.7% and 3.0%, respectively, and the range of mean percent nucleotide distance of S and C regions between Iranians and the other reference isolates were 7.9%-17.5% and 4.8%-14.7%, respectively. Thirteen out of 23 HBV C region sequences showed nucleotide "A" at position 1896 (precore mutant) in C region. Nucleotide 1858 showed presence of "T" in all isolates. No insertion or deletion was found in both regions. SimPlot and BootScanning analyses did not show any recombination between Iranian isolates and other genotypes in both regions. 相似文献