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排序方式: 共有9666条查询结果,搜索用时 15 毫秒
1.
Junyu Wang Daniel S. Weller Christopher M. Kramer Michael Salerno 《NMR in biomedicine》2022,35(5):e4661
The objective of the current study was to develop and evaluate a DEep learning-based rapid Spiral Image REconstruction (DESIRE) technique for high-resolution spiral first-pass myocardial perfusion imaging with whole-heart coverage, to provide fast and accurate image reconstruction for both single-slice (SS) and simultaneous multislice (SMS) acquisitions. Three-dimensional U-Net–based image enhancement architectures were evaluated for high-resolution spiral perfusion imaging at 3 T. The SS and SMS MB = 2 networks were trained on SS perfusion images from 156 slices from 20 subjects. Structural similarity index (SSIM), peak signal-to-noise ratio (PSNR), and normalized root mean square error (NRMSE) were assessed, and prospective images were blindly graded by two experienced cardiologists (5: excellent; 1: poor). Excellent performance was demonstrated for the proposed technique. For SS, SSIM, PSNR, and NRMSE were 0.977 [0.972, 0.982], 42.113 [40.174, 43.493] dB, and 0.102 [0.080, 0.125], respectively, for the best network. For SMS MB = 2 retrospective data, SSIM, PSNR, and NRMSE were 0.961 [0.950, 0.969], 40.834 [39.619, 42.004] dB, and 0.107 [0.086, 0.133], respectively, for the best network. The image quality scores were 4.5 [4.1, 4.8], 4.5 [4.3, 4.6], 3.5 [3.3, 4], and 3.5 [3.3, 3.8] for SS DESIRE, SS L1-SPIRiT, MB = 2 DESIRE, and MB = 2 SMS-slice-L1-SPIRiT, respectively, showing no statistically significant difference (p = 1 and p = 1 for SS and SMS, respectively) between L1-SPIRiT and the proposed DESIRE technique. The network inference time was ~100 ms per dynamic perfusion series with DESIRE, while the reconstruction time of L1-SPIRiT with GPU acceleration was ~ 30 min. It was concluded that DESIRE enabled fast and high-quality image reconstruction for both SS and SMS MB = 2 whole-heart high-resolution spiral perfusion imaging. 相似文献
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de Morais Pollyana C. V. Gama Allyne F. Fernandes Gabrielle M. Oliveira Andre H. B. Lima Marcielly F. B. dos Santos Felipe R. Martins Davi A. Nascimento Ronaldo F. Cavalcante Rivelino M. 《Bulletin of environmental contamination and toxicology》2019,102(1):66-76
Bulletin of Environmental Contamination and Toxicology - This work describes the development of an analytical protocol combining cleanup by liquid–solid extraction and GC–MS for the... 相似文献
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Hertler Caroline Eisele Günter Gramatzki Dorothee Seystahl Katharina Wolpert Fabian Roth Patrick Weller Michael 《Journal of neuro-oncology》2020,147(3):663-669
Journal of Neuro-Oncology - Gliomas are primary brain tumors with a life-limiting course of disease, and the last weeks of life are often characterized by neurological deficits that affect... 相似文献
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Behzad Bidadi Andrea Watson Brenda Weigel Andre Oliveira Justin Kirkham Carola Arndt 《Pediatric blood & cancer》2020,67(6)
Infantile myofibromatosis (IM) is characterized by solitary musculoskeletal nodules presenting during infancy but can manifest as multiple lesions with visceral involvement. Multicentric IM with visceral involvement carries a high risk of mortality and there is no consensus on treatment. We present a case of a patient with multicentric IM and pulmonary involvement who progressed on several chemotherapeutic regimens and subsequently had a complete response to sorafenib and later imatinib. This report describes the novel use of sorafenib and imatinib to treat generalized IM and the role of continued tyrosine kinase inhibitor therapy to maintain remission. 相似文献
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Brett A. Campbell Hanbin Cho Riley M. Faulhammer Olivia Hogue Jenny Peih-Chir Tsai M. Shazam Hussain Andre G. Machado Kenneth B. Baker 《Neuromodulation》2022,25(6):804-816
ObjectivesTo characterize and compare the stability of cortical potentials evoked by deep brain stimulation (DBS) of the subthalamic nucleus (STN) across the naïve, parkinsonian, and pharmacologically treated parkinsonian states. To advance cortical potentials as possible biomarkers for DBS programming.Materials and MethodsSerial electrocorticographic (ECoG) recordings were made more than nine months from a single non-human primate instrumented with bilateral ECoG grids spanning anterior parietal to prefrontal cortex. Cortical evoked potentials (CEPs) were generated through time-lock averaging of the ECoG recordings to DBS pulses delivered unilaterally in the STN region using a chronically implanted, six-contact, scaled DBS lead. Recordings were made across the naïve followed by mild and moderate parkinsonian conditions achieved by staged injections of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxin. In addition to characterizing the spatial distribution and stability of the response within each state, changes in the amplitude and latency of CEP components as well as in the frequency content were examined in relation to parkinsonian severity and dopamine replacement.ResultsIn the naïve state, the STN DBS CEP presented as a multiphase response maximal over M1 cortex, with components attributable to physiological activity distinguishable from stimulus artifact as early as 0.45–0.75 msec poststimulation. When delivered using therapeutically effective parameters in the parkinsonian state, the CEP was highly stable across multiple recording sessions within each behavioral state. Across states, significant differences were present with respect to both the latency and amplitude of individual response components, with greater differences present for longer-latency components (all p < 0.05). Power spectral density analysis revealed a high-beta peak within the evoked response, with significant changes in power between disease states across multiple frequency bands.ConclusionsOur findings underscore the spatiotemporal specificity and relative stability of the DBS-CEP associated with different disease states and with therapeutic benefit. DBS-CEP may be a viable biomarker for therapeutic programming. 相似文献
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Johanna C. Bendell Tamara Sauri Antonio Cubillo Gracián Rafael Alvarez Carlos López-López Pilar García-Alfonso Maen Hussein Maria-Luisa Limon Miron Andrés Cervantes Clara Montagut Cristina Santos Vivas Alberto Bessudo Patricia Plezia Veerle Moons Johannes Andel Jaafar Bennouna Andre van der Westhuizen Leslie Samuel Simona Rossomanno Christophe Boetsch Angelika Lahr Izolda Franjkovic Florian Heil Katharina Lechner Oliver Krieter Herbert Hurwitz for the McCAVE Study Group 《The oncologist》2020,25(3):e451-e459