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排序方式: 共有5497条查询结果,搜索用时 31 毫秒
1.
Martin V. Andersen Cooper Moore Peter Søgaard Daniel Friedman Brett D. Atwater Kristine Arges Melissa LeFevre Johannes J. Struijk Joseph Kisslo Samuel E. Schmidt Olaf T. von Ramm 《Ultrasound in medicine & biology》2019,45(5):1197-1207
Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis. 相似文献
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Haidar S. Dafsari Pablo Martinez‐Martin Alexandra Rizos Maja Trost Maria Gabriela dos Santos Ghilardi Prashanth Reddy Anna Sauerbier Jan Niklas Petry‐Schmelzer Milica Kramberger Robbert W. K. Borgemeester Michael T. Barbe Keyoumars Ashkan Monty Silverdale Julian Evans Per Odin Erich Talamoni Fonoff Gereon R. Fink Tove Henriksen Georg Ebersbach Zvezdan Pirtoek Veerle Visser‐Vandewalle Angelo Antonini Lars Timmermann K. Ray Chaudhuri 《Movement disorders》2019,34(3):353-365
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Journal of NeuroVirology - Modern antiretroviral combination therapy (cART) has transformed HIV from a life-threatening infection into a chronic disease. However, the life-long treatment has side... 相似文献
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Jonas Leichsenring Peter Horak Simon Kreutzfeldt Christoph Heining Petros Christopoulos Anna-Lena Volckmar Olaf Neumann Martina Kirchner Carolin Ploeger Jan Budczies Christoph E. Heilig Barbara Hutter Martina Fröhlich Sebastian Uhrig Daniel Kazdal Michael Allgäuer Alexander Harms Eugen Rempel Ulrich Lehmann Michael Thomas Nicole Pfarr Ninel Azoitei Irina Bonzheim Ralf Marienfeld Peter Möller Martin Werner Falko Fend Melanie Boerries Nikolas von Bubnoff Silke Lassmann Thomas Longerich Michael Bitzer Thomas Seufferlein Nisar Malek Wilko Weichert Peter Schirmacher Roland Penzel Volker Endris Benedikt Brors Frederick Klauschen Hanno Glimm Stefan Fröhling Albrecht Stenzinger 《International journal of cancer. Journal international du cancer》2019,145(11):2996-3010
Next-generation sequencing has become a cornerstone of therapy guidance in cancer precision medicine and an indispensable research tool in translational oncology. Its rapidly increasing use during the last decade has expanded the options for targeted tumor therapies, and molecular tumor boards have grown accordingly. However, with increasing detection of genetic alterations, their interpretation has become more complex and error-prone, potentially introducing biases and reducing benefits in clinical practice. To facilitate interdisciplinary discussions of genetic alterations for treatment stratification between pathologists, oncologists, bioinformaticians, genetic counselors and medical scientists in specialized molecular tumor boards, several systems for the classification of variants detected by large-scale sequencing have been proposed. We review three recent and commonly applied classifications and discuss their individual strengths and weaknesses. Comparison of the classifications underlines the need for a clinically useful and universally applicable variant reporting system, which will be instrumental for efficient decision making based on sequencing analysis in oncology. Integrating these data, we propose a generalizable classification concept featuring a conservative and a more progressive scheme, which can be readily applied in a clinical setting. 相似文献
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Louise Devantier Allan K. Hansen Jens‐Jacob Mlby‐Henriksen Christian B. Christensen Michael Pedersen Kim V. Hansen Mns Magnusson Therese Ovesen Per Borghammer 《Human brain mapping》2020,41(1):185-193
The existence of a human primary vestibular cortex is still debated. Current knowledge mainly derives from functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) acquisitions during artificial vestibular stimulation. This may be problematic as artificial vestibular stimulation entails coactivation of other sensory receptors. The use of fMRI is challenging as the strong magnetic field and loud noise during MRI may both stimulate the vestibular organ. This study aimed to characterize the cortical activity during natural stimulation of the human vestibular organ. Two fluorodeoxyglucose (FDG)‐PET scans were obtained after natural vestibular stimulation in a self‐propelled chair. Two types of stimuli were applied: (a) rotation (horizontal semicircular canal) and (b) linear sideways movement (utriculus). A comparable baseline FDG‐PET scan was obtained after sitting motion‐less in the chair. In both stimulation paradigms, significantly increased FDG uptake was measured bilaterally in the medial part of Heschl's gyrus, with some overlap into the posterior insula. This is the first neuroimaging study to visualize cortical processing of natural vestibular stimuli. FDG uptake was demonstrated in the medial‐most part of Heschl's gyrus, normally associated with the primary auditory cortex. This anatomical localization seems plausible, considering that the labyrinth contains both the vestibular organ and the cochlea. 相似文献
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Suvi Renkonen Lars‐Olaf Cardell Petri Mattila Marie Lundberg Caj Haglund Antti A. Mäkitie 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(5):439-444
Juvenile nasopharyngeal angiofibroma (JNA) is a rare, benign tumor affecting adolescent males. The etiology of JNA as well as the causes determining the variable growth patterns of individual tumors remains unknown. Toll‐like receptors (TLRs) are part of the innate immune response to microbes; by recognition of distinct features, they link to induction of pro‐inflammatory signaling pathways. We immunostained TLR 3, 7, and 9 in 27 JNA specimens of patients treated at the Helsinki University Central Hospital, Helsinki, Finland, during the years 1970–2009. Results: TLR 3, 7, and 9 expressions were found in stromal and endothelial cells of JNA, and their expression levels varied from negative to very strong positive. TLR 3 expression was found to have a significant correlation with the clinical stage of JNA. Conclusions: The present results propose a putative role of TLRs in the growth process of JNA. 相似文献
9.
Stefan Esser Alexander Kreuter Mark Oette Andrea Gingelmaier Franz Mosthaf Marie‐Luise Sautter‐Bihl Johannes Jongen Norbert H. Brockmeyer Gerd Eldering Jochen Swoboda Nils Postel Olaf Degen Horst Schalk Arne Jessen Heribert Knechten Jan Thoden Hans‐Jürgen Stellbrink Armin Schafberger Ulrike Wieland 《Journal der Deutschen Dermatologischen Gesellschaft》2015,13(12):1302-1319
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