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排序方式: 共有249条查询结果,搜索用时 15 毫秒
1.
Vijay Gayam Venu M. Konala Srikanth Naramala Pavani Reddy Garlapati Mohamed A. Merghani Nirajan Regmi Mamtha Balla Sreedhar Adapa 《Journal of medical virology》2020,92(10):2181-2187
Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is spreading at a rapid pace, and the World Health Organization declared it as pandemic on 11 March 2020. Mycoplasma pneumoniae is an "atypical" bacterial pathogen commonly known to cause respiratory illness in humans. The coinfection from SARS-CoV-2 and mycoplasma pneumonia is rarely reported in the literature to the best of our knowledge. We present a study in which 6 of 350 patients confirmed with COVID-19 were also diagnosed with M. pneumoniae infection. In this study, we described the clinical characteristics of patients with coinfection. Common symptoms at the onset of illness included fever (six [100%] patients); five (83.3%) patients had a cough, shortness of breath, and fatigue. The other symptoms were myalgia (66.6%), gastrointestinal symptoms (33.3%-50%), and altered mental status (16.7%). The laboratory parameters include lymphopenia, elevated erythrocyte sedimentation rate, C-reactive protein, lactate dehydrogenase, interleukin-6, serum ferritin, and D-dimer in all six (100%) patients. The chest X-ray at presentation showed bilateral infiltrates in all the patients (100%). We also described electrocardiogram findings, complications, and treatment during hospitalization in detail. One patient died during the hospital course. 相似文献
2.
Wellbore-plugging materials are threatened by challenging plugging and abandonment (P&A) conditions. Hence, the integrity and resilience of these materials and their ability to provide sufficient zonal isolation in the long-term are unknown. The present work focuses on investigating the potential to use zeolites as novel additives to the commonly used Class-H cement. Using four different zeolite–cement mixtures (0%, 5%, 15% and 30%, by weight of cement) where samples were cast as cylinders and cured at 90 °C and 95% relative humidity, the unconfined compressive strength (UCS) testing showed a 41% increase with the 5% ferrierite addition to the Class-H cement in comparison to neat Class-H cement. For triaxial compression tests at 90 °C, the highest strength achieved by the 5% ferrierite-added formulations was 68.8 MPa in comparison to 62.9 MPa for the neat Class-H cement. The 5% ferrierite formulation also showed the lowest permeability, 13.54 μD, which is in comparison to 49.53 μD for the neat Class-H cement. The overall results show that the 5% ferrierite addition is the most effective at improving the mechanical and petrophysical properties based on a water/cement ratio of 0.38 when tested after 28 days of curing in 95% relative humidity and 90 °C. Our results not only demonstrate that zeolite is a promising cement additive that could improve the long-term strength and petrophysical properties of cement formulations, but also provide a proposed optimal formulation that could be next utilized in a field trial. 相似文献
3.
Richard S P Huang Julie Y Tse Lukas Harries Ryon P Graf Douglas I Lin Karthikeyan Murugesan Matthew C Hiemenz Vamsi Parimi Tyler Janovitz Brennan Decker Eric Severson Mia A Levy Shakti H Ramkissoon Julia A Elvin Jeffrey S Ross Erik A Williams 《The oncologist》2022,27(8):655
BackgroundIn the current study, we examined the real-world prevalence of highly pigmented advanced melanomas (HPMel) and the clinicopathologic, genomic, and ICPI biomarker signatures of this class of tumors.Materials and MethodsOur case archive of clinical melanoma samples for which the ordering physician requested testing for both PD-L1 immunohistochemistry (IHC) and comprehensive genomic profiling (CGP) was screened for HPMel cases, as well as for non-pigmented or lightly pigmented advanced melanoma cases (LPMel).ResultsOf the 1268 consecutive melanoma biopsies in our archive that had been submitted for PD-L1 IHC, 13.0% (165/1268) were HPMel and 87.0% (1103/1268) were LPMel. In the HPMel cohort, we saw a significantly lower tumor mutational burden (TMB, median 8.8 mutations/Mb) than in the LPMel group (11.4 mut/Mb), although there was substantial overlap. In examining characteristic secondary genomic alterations (GA), we found that the frequencies of GA in TERTp, CDKN2A, TP53, and PTEN were significantly lower in the HPMel cases than in LPMel. A higher rate of GA in CTNNB1, APC, PRKAR1A, and KIT was identified in the HPMel cohort compared with LPMel.ConclusionsIn this study, we quantified the failure rates of melanoma samples for PD-L1 testing due to high melanin pigmentation and showed that CGP can be used in these patients to identify biomarkers that can guide treatment decisions for HPMel patients. Using this practical clinical definition for tumor pigmentation, our results indicate that HPMel are frequent at 13% of melanoma samples, and in general appear molecularly less developed, with a lower TMB and less frequent secondary GA of melanoma progression. 相似文献
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Lavu Vamsi Gutknecht Norbert Vasudevan Amrutha S.K Balaji Hilgers Ralf-Dieter Franzen Rene 《Lasers in medical science》2022,37(3):1625-1634
Lasers in Medical Science - The objective of this prospective randomized controlled single-center clinical trial was to prove the efficacy of adjunctive photobiomodulation in improving selected... 相似文献
7.
In the current petroleum refining scenario, many refineries end up with surplus naphtha which is either absorbed into the gasoline pool or exported at unattractive prices. Therefore, several options for naphtha valorisation are currently being explored. The usage of Liquified Petroleum Gas (LPG) as a fuel in heating appliances, cooking equipment and automobiles is rapidly increasing. The high specific calorific value, high octane number, clean and efficient combustion of LPG distinguish it as an extremely promising fuel of the future. In the current work, tungstophosphoric acid (TPA) supported on four different mesoporous silica supports were investigated as mesoporous superacids for hydroconversion of refinery naphtha using n-heptane as a model feedstock. The varied levels of interactions of prepared mesoporous silica with tungstophosphoric acid catalysts were observed to have a prominent effect on the strength of the acid sites generated on silica surfaces and as a result affected heptane hydroconversion activity and selectivity of isomerized and cracked products. Interestingly, activity could be tuned towards selective cracking or isomerization-cracking by selection of a suitable topology of mesoporous silica. Hexagonal Mesoporous Silica (HMS) and plugged SBA-15 supported TPA catalysts demonstrated high n-heptane conversion activity and isomerization selectivity whereas KIT-6 and SBA-15 supported TPA catalysts demonstrated high cracking selectivity to LPG.TPA silanol interactions in mesoporous TPA silica composites govern the strength of acid sites, activity and selectivity. 相似文献
8.
Identification of a gene causing human cytochrome c oxidase deficiency by integrative genomics 总被引:2,自引:0,他引:2
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9.
Extracting and summarizing white matter hyperintensities using supervised segmentation methods in Alzheimer's disease risk and aging studies
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Vamsi Ithapu Vikas Singh Christopher Lindner Benjamin P. Austin Chris Hinrichs Cynthia M. Carlsson Barbara B. Bendlin Sterling C. Johnson 《Human brain mapping》2014,35(8):4219-4235
Precise detection and quantification of white matter hyperintensities (WMH) observed in T2‐weighted Fluid Attenuated Inversion Recovery (FLAIR) Magnetic Resonance Images (MRI) is of substantial interest in aging, and age‐related neurological disorders such as Alzheimer's disease (AD). This is mainly because WMH may reflect co‐morbid neural injury or cerebral vascular disease burden. WMH in the older population may be small, diffuse, and irregular in shape, and sufficiently heterogeneous within and across subjects. Here, we pose hyperintensity detection as a supervised inference problem and adapt two learning models, specifically, Support Vector Machines and Random Forests, for this task. Using texture features engineered by texton filter banks, we provide a suite of effective segmentation methods for this problem. Through extensive evaluations on healthy middle‐aged and older adults who vary in AD risk, we show that our methods are reliable and robust in segmenting hyperintense regions. A measure of hyperintensity accumulation, referred to as normalized effective WMH volume, is shown to be associated with dementia in older adults and parental family history in cognitively normal subjects. We provide an open source library for hyperintensity detection and accumulation (interfaced with existing neuroimaging tools), that can be adapted for segmentation problems in other neuroimaging studies. Hum Brain Mapp 35:4219–4235, 2014. © 2014 Wiley Periodicals, Inc . 相似文献
10.
Background: Monocyte subsets with low CD14 expression that coexpress CD16 (CD14+CD16+) are called non‐classic or hyperinflammatory monocytes. Previous studies have reported an increase in the percentage of CD14+CD16+ monocytes in the peripheral blood of patients with chronic periodontitis (CP). To our knowledge, there are no reports demonstrating the presence of CD14+CD16+ monocyte–derived macrophages (MDMs) in the gingival tissue. The objective of this study is to identify the proportion of non‐classic (CD14+CD16+) monocytes/macrophages in peripheral blood and gingiva of healthy individuals and patients with CP. Methods: A total of 60 individuals (n = 30 per group) were recruited for the study. Group 1 included 30 individuals with healthy gingiva, and group 2 included 30 patients with CP. Direct immunofluorescent staining was done in 200 μL whole‐blood and single‐cell suspensions obtained from gingival tissue, with fluorochrome‐conjugated monoclonal antibodies against CD14, CD16, and human leukocyte antigen‐DR (HLA‐DR), and subjected to flow cytometric analysis. Results: The mean percentage of CD14+CD16+ monocytes in the peripheral blood of healthy individuals was 9.10% ± 1.39%, and for patients with CP it was 14.18% ± 2.69% (P <0.05). The mean percentage of CD14+CD16+ MDMs in the gingival tissue of healthy individuals was found to be 0.93% ± 0.33%, whereas in patients with CP, it was 1.92% ± 0.78% (P <0.01). Non‐classic monocytes/macrophages showed a high median fluorescent intensity for HLA‐DR (DR++). Conclusion: This study demonstrates an increased proportion of CD14+CD16+HLA‐DR++ monocytes/macrophages in the peripheral blood and gingiva of patients with CP. 相似文献