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Journal of Neuro-Oncology - The role of white blood cells (WBC) in the pediatric central nervous system (CNS) tumor microenvironment is incompletely defined. We hypothesized that the WBC profile in...  相似文献   
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Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of...  相似文献   
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Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia.  相似文献   
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Quantitative ultrasound (QUS) was used to classify rabbits that were induced to have liver disease by placing them on a fatty diet for a defined duration and/or periodically injecting them with CCl4. The ground truth of the liver state was based on lipid liver percents estimated via the Folch assay and hydroxyproline concentration to quantify fibrosis. Rabbits were scanned ultrasonically in vivo using a SonixOne scanner and an L9-4/38 linear array. Liver fat percentage was classified based on the ultrasonic backscattered radiofrequency (RF) signals from the livers using either QUS or a 1-D convolutional neural network (CNN). Use of QUS parameters with linear regression and canonical correlation analysis demonstrated that the QUS parameters could differentiate between livers with lipid levels above or below 5%. However, the QUS parameters were not sensitive to fibrosis. The CNN was implemented by analyzing raw RF ultrasound signals without using separate reference data. The CNN outputs the classification of liver as either above or below a threshold of 5% fat level in the liver. The CNN outperformed the classification utilizing the QUS parameters combined with a support vector machine in differentiating between low and high lipid liver levels (i.e., accuracies of 74% versus 59% on the testing data). Therefore, although the CNN did not provide a physical interpretation of the tissue properties (e.g., attenuation of the medium or scatterer properties) the CNN had much higher accuracy in predicting fatty liver state and did not require an external reference scan.  相似文献   
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The risk of fragility fracture increases for people with type 2 diabetes mellitus (T2DM), even after controlling for bone mineral density, body mass index, visual impairment, and falls. We hypothesize that progressive glycemic derangement alters microscale bone tissue composition. We used Fourier-transform infrared (FTIR) imaging to analyze the composition of iliac crest biopsies from cohorts of postmenopausal women characterized by oral glucose tolerance testing: normal glucose tolerance (NGT; n = 35, age = 65 ± 7 years, HbA1c = 5.8 ± 0.3%), impaired glucose tolerance (IGT; n = 26, age = 64 ± 5 years, HbA1c = 6.0 ± 0.4%), and overt T2DM on insulin (n = 25, age = 64 ± 6 years, HbA1c = 9.13 ± 0.6). The distributions of cortical bone mineral content had greater mean values (+7%) and were narrower (−10%) in T2DM versus NGT groups (p < 0.05). The distributions of acid phosphate, an indicator of new mineral, were narrower in cortical T2DM versus NGT and IGT groups (−14% and −14%, respectively) and in trabecular NGT and IGT versus T2DM groups (−11% and −10%, respectively) (all p < 0.05). The distributions of crystallinity were wider in cortical NGT versus T2DM groups (+16%) and in trabecular NGT versus T2DM groups (+14%) (all p < 0.05). Additionally, bone turnover was lower in T2DM versus NGT groups (P1NP: −25%, CTx: −30%, ucOC: −24%). Serum pentosidine was similar across groups. The FTIR compositional and biochemical marker values of the IGT group typically fell between the NGT and T2DM group values, although the differences were not always statistically significant. In summary, worsening glycemic control was associated with greater mineral content and narrower distributions of acid phosphate, an indicator of new mineral, which together are consistent with observations of lower turnover; however, wider distributions of mineral crystallinity were also observed. A more mineralized, less heterogeneous tissue may affect tissue-level mechanical properties and in turn degrade macroscale skeletal integrity. In conclusion, these data are the first evidence of progressive alteration of bone tissue composition with worsening glycemic control in humans. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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