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COVID‐19 showed different characteristics, and many cases showed clinical manifestations that could not be attributed to other conditions. We present a 22‐year‐old woman who had an uneventful recovery from COVID‐19, and after that, she developed a cytokine storm and a worsening clinical condition 2 days after dental root canal therapy.  相似文献   
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Although an increasing number of studies have been conducted to evaluate the association between human papillomavirus (HPV) infections and distribution of HPV types worldwide with the risk of prostate cancer (PC), the results remain inadequate. Hence, we investigated the association between HPV infection and PC risk using a meta‐analysis. Relevant studies from January 1990 to December 2016 were searched in PubMed, Web of sciences, and Scopus databases. Pooled odds ratio (OR) and their corresponding 95% confidence interval (CI) were calculated to find the association between the prevalence of HPV and prostate cancer risk. To do so, data from 24 studies with 5546 prostate cancer cases were pooled in order to evaluate the heterogeneity of chief parameters including study region, specimen type, HPV DNA source, detection technique, publication calendar period, and Gleason score. All statistical analyses were performed using STATA 11 and MedCalc 13. A significant positive association was found between HPV infection and PC risk (OR = 1.281; P = 0.026). The genotype 16 was more frequently found in patients with PC which significantly increased the cancer risk (OR = 1.60; P < 0.001). Age 65 and older could significantly escalate PC risk (OR = 3.564; P < 0.001). Our results clearly favor the potential pathogenetic link between HPV infection and increased risk of PC affirming that HPV infections could play a part in the risk of PC.  相似文献   
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In this paper, we investigate the redox performance of perovskite coated porous ceramics with various architectures. For this purpose, reticulated porous ceramics (RPCs) in three different pore sizes (5, 12, 75 ppi) were fabricated to represent a broad range of structures and pore sizes. The perovskite material is based on lanthanum manganite and was synthesized and doped with Ca and Al through the Pechini method. Using a deep coating method, the surface of RPC substrates was modified by a thin-film coating with a thickness of ∼15 μm. We evaluated the CO2 conversion performance of the developed materials in a gold-image IR furnace. X-ray micro-computed tomography along with SEM/EDX were utilized in different steps of the work for a thorough study of the bulk and surface features. Results reveal that the intermediate pore size of 12 ppi delivers the maximum perovskite loading with a high degree of coating homogeneity and connectivity while CO2 conversion tests showed the highest CO yield for 75 ppi. Our results show that the extreme conditions inside the furnace combined with the flow of gaseous phases cause the RPCs to shrink in length up to 23% resulting in the alteration of the pore phase and elimination of small pores reducing the total specific surface area. Further our results reveal an important mechanism resulting in the inhibition of CO2 conversion where the perovskite coating layer migrates into the matrix of the RPC frame.

A representative volume of LCMA coated porous SiC showing a maximum of 23% shrinkage when subject to high-temperature CO2 conversion redox reactions. This results in significant structural changes including a reduction in specific surface area.  相似文献   
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Quantum mechanics-based simulations have been undertaken to support the development and application of multi-functional nano-devices constructed from zigzag silicon carbide nanoribbons (zSiCNRs), boron phosphide (BP), nanoribbons (zBPNRs), and Pb-chalcogenide (PbS, PbSe) nanoribbons. We explore the effect of gate voltage on the electronic performance of the devices. Symmetric IV characteristics, spin polarization properties, NDR effects, and high rectification ratios are observed among these devices. The effects of the angle, length and width of the constructed nanoribbon are also studied. The results show that the width of the nanoribbons can have a substantial influence on their electronic performance. These results provide a crucial simulation input to help guide the design of multi-functional nano-devices built from hybrid SiC–BP/PbS/PbSe nanostructures, and this research is essential for better understanding of their electronic transport properties.

Quantum mechanics-based simulations have been undertaken to support the development and application of multi-functional nano-devices constructed from zigzag silicon carbide nanoribbons, boron phosphide, nanoribbons, and Pb-chalcogenide (PbS, PbSe) nanoribbons.  相似文献   
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