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41.
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Yicheng Chen Ozan Genc Clare B. Poynton Suchandrima Banerjee Christopher P. Hess Janine M. Lupo 《NMR in biomedicine》2022,35(5):e4666
Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength. 相似文献
43.
Alexander D. Sherry MD Kelsey L. Corrigan MD MPH Ramez Kouzy MD Joseph Abi Jaoude MD Yumeng Yang MS Roshal R. Patel MD Douglas J. Totten MD MBA Neil B. Newman MD MS Prajnan Das MD MS MPH Cullen Taniguchi MD PhD Bruce Minsky MD Rebecca A. Snyder MD MPH C. David Fuller MD PhD Ethan Ludmir MD 《Cancer》2023,129(21):3430-3438
44.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion. 相似文献
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Brandstetter Susanne Pawellek Maja Böhmer Merle M. Köninger Angela Melter Michael Kabesch Michael Apfelbacher Christian 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2022,65(12):1281-1288
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Mit Beginn der Impfkampagne hat eine neue Phase der Bewältigung der Coronapandemie begonnen. Zulassung und Empfehlung... 相似文献
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Cho Nicholas Wang Chencai Raymond Catalina Kaprealian Tania Ji Matthew Salamon Noriko Pope Whitney B. Nghiemphu Phioanh L. Lai Albert Cloughesy Timothy F. Ellingson Benjamin M. 《Journal of neuro-oncology》2020,147(3):643-652
Journal of Neuro-Oncology - There is growing evidence that the subventricular zone (SVZ) plays a key role in glioblastoma (GBM) tumorigenesis. However, little is known regarding how the SVZ, which... 相似文献
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Malinda Itchins Brandon Lau Amanda L. Hudson Helen Westman Cathy Yi Xia Sarah A. Hayes Viive M. Howell Michael Rodriguez Wendy A. Cooper Heng Wei Michael Buckland Bob T. Li Mark Li Vivek Rathi Stephen B. Fox Anthony J. Gill Stephen J. Clarke Michael J. Boyer Nick Pavlakis 《The oncologist》2020,25(8):641-649