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991.
Vasconcelos Camila Vilela Costa Alan Carlos Müller Caroline Castoldi Gustavo Costa Andréia Mendes de Paula Barbosa Kássia Rodrigues Arthur Almeida da Silva Adinan Alves 《Ecotoxicology (London, England)》2020,29(2):203-216
Ecotoxicology - Common bean (Phaseolus vulgaris) cultivation occurs mainly in regions with acidic soils, where high aluminum (Al) concentration is a major constraint to crop production. In this... 相似文献
992.
993.
Catharina M. L. Zegers Wouter van Elmpt Katrin Szardenings Hartmuth Kolb Alan Waxman Rathan M. Subramaniam Dae Hyuk Moon Jacqueline C. Brunetti Shyam M. Srinivas Philippe Lambin David Chien 《European journal of nuclear medicine and molecular imaging》2015,42(12):1840-1849
Purpose
Hypoxia is an important factor influencing tumor progression and treatment efficacy. The aim of this study was to investigate the repeatability of hypoxia PET imaging with [18F]HX4 in patients with head and neck and lung cancer.Methods
Nine patients with lung cancer and ten with head and neck cancer were included in the analysis (NCT01075399). Two sequential pretreatment [18F]HX4 PET/CT scans were acquired within 1 week. The maximal and mean standardized uptake values (SUVmax and SUVmean) were defined and the tumor-to-background ratios (TBR) were calculated. In addition, hypoxic volumes were determined as the volume of the tumor with a TBR >1.2 (HV1.2). Bland Altman analysis of the uptake parameters was performed and coefficients of repeatability were calculated. To evaluate the spatial repeatability of the uptake, the PET/CT images were registered and a voxel-wise comparison of the uptake was performed, providing a correlation coefficient.Results
All parameters of [18F]HX4 uptake were significantly correlated between scans: SUVmax (r?=?0.958, p?<?0.001), SUVmean (r?=?0.946, p?<?0.001), TBRmax (r?=?0.962, p?<?0.001) and HV1.2 (r?=?0.995, p?<?0.001). The relative coefficients of repeatability were 15 % (SUVmean), 17 % (SUVmax) and 17 % (TBRmax). Voxel-wise analysis of the spatial uptake pattern within the tumors provided an average correlation of 0.65?±?0.14.Conclusion
Repeated hypoxia PET scans with [18F]HX4 provide reproducible and spatially stable results in patients with head and neck cancer and patients with lung cancer. [18F]HX4 PET imaging can be used to assess the hypoxic status of tumors and has the potential to aid hypoxia-targeted treatments.994.
Alan A. Saber Nami Azar Mahmoud Dekal Tamer N. Abdelbaki 《American journal of surgery》2015,209(6):999-1006
Background
Several postoperative gastrointestinal complications are attributed to ischemia. We herein evaluate the gastric wall perfusion using computed tomography (CT) scan perfusion index on trial to address the etiology of ischemic complication after sleeve gastrectomy.Methods
A retrospective study of 205 patients undergoing CT scan of the abdomen to evaluate the pattern of gastric vascular perfusion was performed. The perfusion index of the gastric mucosa was measured at 5 gastric points using CT perfusion scanning.Results
Gastric perfusion at the angle of His (AOH) (53.51 ± 14.38) was statistically significantly lower (P < .001) than that at the other gastric points studied: fundus, greater curvature, lesser curvature, incisura angularis, and mid gastric points (76.16 ± 15.21, 73.27 ± 16.55, 76.12 ± 16.12, and 75.24 ± 14.9, respectively). Gastric perfusion was significantly lower at all the gastric points (and especially so at the AOH) among obese patients (33 cases) compared with nonobese patients (18 cases). Gastric perfusion at all the points studied showed a decrease as the body mass index increases. Hypertensive patients had a better gastric perfusion compared with nonhypertensive patients.Conclusions
Gastric wall perfusion is statistically significantly decreased at the AOH and gastric fundus compared with perfusion at other gastric points. Gastric perfusion at all the gastric points studied decreased with the increase in body mass index. Gastric leakage in obese patients following sleeve gastrectomy could be attributed to a decrease in the blood supply at AOH. 相似文献995.
996.
Rakesh M. Suri Brian C. Gulack J. Matthew Brennan Vinod H. Thourani Dadi Dai Alan Zajarias Kevin L. Greason Christina M. Vassileva Verghese Mathew Vuyisile T. Nkomo Michael J. Mack Charanjit S. Rihal Lars G. Svensson Rick A. Nishimura Patrick T. O’Gara David R. Holmes Jr. 《The Annals of thoracic surgery》2015,100(6):2136-2146
997.
Cláudia Patrícia Cardoso Martins Siqueira Solange de Paula Ramos Cynthia A. A. Gobbi Leonardo Shigaki Roberto K. Kashimoto Emerson José Venâncio Dari de Oliveira Toginho Filho André G. Castaldin Alan S. Felinto Francisco Pereira Silva Ricardo B. Silva Ivan Frederico Lupiano Dias 《Lasers in medical science》2015,30(1):367-373
998.
999.
1000.
Naiara Rodriguez‐Florez Esther Garcia‐Tunon Quresh Mukadam Eduardo Saiz Karla J Oldknow Colin Farquharson José Luis Millán Alan Boyde Sandra J Shefelbine 《Journal of bone and mineral research》2015,30(5):786-795
Bone is a strong and tough material composed of apatite mineral, organic matter, and water. Changes in composition and organization of these building blocks affect bone's mechanical integrity. Skeletal disorders often affect bone's mineral phase, either by variations in the collagen or directly altering mineralization. The aim of the current study was to explore the differences in the mineral of brittle and ductile cortical bone at the mineral (nm) and tissue (µm) levels using two mouse phenotypes. Osteogenesis imperfecta model, oim‐/‐, mice have a defect in the collagen, which leads to brittle bone; PHOSPHO1 mutants, Phospho1‐/‐, have ductile bone resulting from altered mineralization. Oim‐/‐ and Phospho1‐/‐ were compared with their respective wild‐type controls. Femora were defatted and ground to powder to measure average mineral crystal size using X‐ray diffraction (XRD) and to monitor the bulk mineral to matrix ratio via thermogravimetric analysis (TGA). XRD scans were run after TGA for phase identification to assess the fractions of hydroxyapatite and β‐tricalcium phosphate. Tibiae were embedded to measure elastic properties with nanoindentation and the extent of mineralization with backscattered electron microscopy (BSE SEM). Results revealed that although both pathology models had extremely different whole‐bone mechanics, they both had smaller apatite crystals, lower bulk mineral to matrix ratio, and showed more thermal conversion to β‐tricalcium phosphate than their wild types, indicating deviations from stoichiometric hydroxyapatite in the original mineral. In contrast, the degree of mineralization of bone matrix was different for each strain: brittle oim‐/‐ were hypermineralized, whereas ductile Phospho1‐/‐ were hypomineralized. Despite differences in the mineralization, nanoscale alterations in the mineral were associated with reduced tissue elastic moduli in both pathologies. Results indicated that alterations from normal crystal size, composition, and structure are correlated with reduced mechanical integrity of bone. © 2014 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research. 相似文献