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71.
Bilateral bidirectional Glenn shunts are associated with the risk of developing pulmonary artery bifurcation stenosis, resulting in variable pulmonary blood flow to either lung. This could negatively impact the subsequent stages of the single ventricle palliation pathway. This report highlights the value of 4D flow sequence from the cardiac magnetic resonance imaging in demonstrating the pulmonary blood flow characteristics following a bilateral bidirectional Glenn procedure. Mapping the blood flow pattern and its quantification to each lung provide objective insights into the possible predisposing factors for the development of pulmonary bifurcation stenosis.  相似文献   
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Background:Mesenteric panniculitis (MP) is a non-specific, localized inflammation at the mesentery of small intestines which often gets detected on computed tomography. An association with malignant neoplasms remains unclear. We performed a systematic review and meta-analysis to examine the association of malignancy with MP.Methods:MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched for articles published from inception to 2020 that evaluated the association of malignant neoplasms with MP in comparison with control groups. Using random-effects method, a summary odds ratio (OR) estimate with 95% confidence intervals for malignant neoplasms in MP was estimated.Results:Four case-control studies reporting data on 415 MP patients against 1132 matched-controls met inclusion criteria and were analyzed. The pooled OR for finding a malignant neoplasm in patients with MP was 0.907 (95% CI: 0.688–1.196; P = .489). The heterogeneity was mild and non-significant. Also, there was no heightened risk of any specific type of malignancy with MP. Three more case-series with unmatched-control groups (MP: 282, unmatched-controls: 17,691) were included in a separate analysis where the pooled OR of finding a malignant neoplasm was 2.963 (95% CI: 1.434–6.121; P = .003). There was substantial heterogeneity in this group.Conclusion:This meta-analysis of matched controlled studies proves absence of any significant association of malignant neoplasms with MP. Our study also demonstrates that the putative association of malignancy with MP is mainly driven by uncontrolled studies or case-series.  相似文献   
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Abstract

A receptor level interaction of etoposide with P-glycoprotein (P-gp) and subsequent intestinal efflux has an adverse effect on its oral absorption. The present work is aimed to enhance the bioavailability of etoposide by co-administering it with quercetin (a P-gp inhibitor) in dual-loaded polymeric nanoparticle formulation. Poly-lactic-co-glycolic acid (PLGA) nanoparticles were optimized for various parameters like o/w phase volume ratio, poly-vinyl alcohol concentration, PLGA concentration and sonication time. The cytotoxicity studies (MTT assay) revealed a 9- and 11-fold decrease in the IC 50 values for etoposide-loaded nanoparticles (ENP) and etoposide?+?quercetin dual-loaded nanoparticles (EQNP) when compared to that of free etoposide, respectively, and the results were further supported by florescent-activated cell sorter studies. The confocal imaging of the intestinal sections treated with ENP and EQNP containing fluorescent probe (rhodamine) showed the superiority of the EQNP to permeate deeper. Furthermore, pharmacokinetic studies on rats revealed that EQNP exhibited a 2.4-fold increase in bioavailability of etoposide than ENP with no quercetin. The developed loaded nanoparticles have the high potential to enhance the bioavailability of the etoposide and sensitize the resistant cells.  相似文献   
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Corrosion is frequently viewed as a catastrophic and unavoidable disaster in marine applications. Every year, a huge cost is incurred on the maintenance and repair of corrosion-affected equipment and machinery. In the marine environment, as-cast nickel–aluminium bronze (NAB) is susceptible to selective phase corrosion. To solve this problem, chromium-reinforced nickel–aluminium bronze was fabricated using the friction stir process (FSP) with improved microstructures and surface properties. A slurry erosion–corrosion test on as-cast and FSPed composites demonstrated that the developed surfaced composite has lower erosion and corrosion rates than the as-cast NAB alloy. The erosion–corrosion rate increased with a decrease in the impact angle from 90° to 30° for both as-cast NAB and prepared composites, exhibiting a shear mode of erosion. The specimens at impact angle 30° experienced more pitting action and higher mass loss compared with those at impact angle 90°. Due to increases in the mechanical properties, the FS-processed composite showed higher erosion resistance than the as-cast NAB alloy. Furthermore, corrosion behaviour was also studied via the static immersion corrosion test and electrochemical measurements under 3.5 wt.% NaCl solution. In a static immersion corrosion test, the FSPed composite outperformed the as-cast NAB composite by a wide margin. The FSPed composite also demonstrated a reduced electrochemical corrosion rate, as revealed by the polarization curve and electrochemical impedance spectroscopic (EIS) data. This reduced rate is attributed to the formation of a Cr oxide film over its surface in the corrosive environment.  相似文献   
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The incidence of malignant transformation in mature cystic teratoma (MCT) of the ovary is less than 2% as reported in gynaecological and pathological literature. Here we present a series of five patients, who developed malignant transformation in MCT of the ovary, over a 6-year period (1999–2004). The morphological and clinico-pathological features of malignant transformation in MCT of the ovary are discussed.  相似文献   
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通过哈医大注重学校文化传承与创新建设,在学校发展中起到助推作用的做法及存在问题的探讨,论述了如何进一步推进学校文化建设的思路及措施.  相似文献   
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