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Schwann cells participate in myelin phagocytosis in the early stage of Wallerian degeneration, prior to the recruitment of macrophages. This is the first report that Schwann cells induce heme oxygenase-1 (HO-1), a 32-kDa heat shock protein, only when they have transformed into myelin-phagocytosing cells from myelinating cells (days 2-3) immediately after crush injury of rat sciatic nerves. Double immunofluorescent labelling for HO-1 and transferrin receptors revealed that HO-1-immunoreactive Schwann cells also expressed transferrin receptors suggesting activation of iron metabolism. The transient induction of HO-1 in Schwann cells may contribute to the adaptive function in an altered environment when the cells have lost contact with axons, and may play a crucial role in the ensuing regeneration.  相似文献   
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The water-soluble glucan was obtained from Pleurotus florida fruit bodies by hot water extraction, ethanol precipitation, DEAE cellulose dialysis and Sephadex G-75 gel filtration. The structural information of the glucan was achieved by chemical (hydrolysis, methylation, periodate oxidation) and spectroscopic (1H and 13C) analyses, indicated a repeating unit built up of (1→6)-linked D-glucose. The following structure has been determined for the repeating unit: →6)-α-D-Glcp-(1→ This fraction exhibited significant macrophage activity through the release of nitric oxide  相似文献   
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Purpose:To provide a retrospective analysis of lesions of the caruncle which have been very rarely reported in the literature.Methods:A retrospective review of all the caruncular lesions between January 2000 and January 2020 was done at a single tertiary eye care hospital. The lesions were classified as benign and malignant lesions. Clinicopathological correlation was done for the excised lesions.Results:A total of 87 caruncular lesions were included in the study. Males (59%) were affected more than females (41%). The mean age at presentation was 44 ± 20 years. The mean duration of complaint was 36 ± 62 months. A total of 36 patients underwent surgical excision whereas the rest opted for conservative management. Recurrence was noted in five patients. Fifteen different types of lesions were identified histopathologically. Benign lesions (78%) were far more common than malignant ones (22%). Epithelial inclusion cyst was the most common benign lesion and sebaceous gland carcinoma was the most common malignant lesion. Correct clinicopathological correlation was seen in 52.7% of the cases. Caruncular tuberculosis, oncocytoma, and basosquamous cell carcinoma were some of the rare lesions.Conclusion:Caruncular lesions are uncommon and very diverse, which makes clinical diagnosis challenging. Epithelial inclusion cyst and sebaceous gland carcinoma were the most common benign and malignant lesions respectively. Correct clinicopathological correlation was seen in more than half of the cases.  相似文献   
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正The severity of COVID-19 epidemic is more salient for regions that are heavily reliant on tourism industry. The pandemic along with travel restrictions, border closures and social distancing requirements pose serious threats for the sustainability of tourism sectors in many regions of Indonesia, putting livelihoods for the whole societies at risk.  相似文献   
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Ginseng is one of the most commonly used adaptogens. Transformation into the minor ginsenosides produces compounds with more effective action. Beauveria bassiana, a teleomorph of Cordyceps bassiana, is a highly efficient producer of mammalian steroids and produces large amounts of sugar‐utilizing enzymes. However, the fermentation of steroid glycosides in ginseng with B. bassiana has never been studied. Thus, we evaluated the bioconversion of the major ginsenosides in white ginseng by B. bassiana. Interestingly, B. bassiana increased the total amount of protopanaxadiols and hydrolyzed Rb1 into minor ginsenosides, exhibiting high levels of Rd and Rg3, as well as moderate levels of Rb2 and Rc analyzed by high‐performance liquid chromatography coupled with evaporative light‐scattering detection. The β‐glucosidase activity was highly increased, which led to the selective elimination of sugar moiety at the 20‐C position of Rb1 to Rd, followed by Rg3. Rb2 and Rc accumulated because of the minimal activities of α‐L‐arabinopyranosidase and α‐L‐arabinofuranosidase, respectively. The fermentation product exerted dose‐dependent cytotoxicity in HCT‐15 cells, which are resistant to ginseng. The product, but not white ginseng, exhibited apoptotic effects via the Fas ligand and caspase 8/9. This study demonstrates for the first time that the B. bassiana‐fermented metabolites have potent apoptotic activity in colon cancer cells, linking to a therapeutic use. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this review, the most recent advances in the field of magnetic composite photocatalysts with integrated plasmonic silver (Ag) is presented, with an overview of their synthesis techniques, properties and photocatalytic pollutant removal applications. Magnetic attributes combined with plasmonic properties in these composites result in enhancements for light absorption, charge-pair generation-separation-transfer and photocatalytic efficiency with the additional advantage of their facile magnetic separation from water solutions after treatment, neutralizing the issue of silver’s inherent toxicity. A detailed overview of the currently utilized synthesis methods and techniques for the preparation of magnetic silver-integrated composites is presented. Furthermore, an extended critical review of the most recent pollutant removal applications of these composites via green photocatalysis technology is presented. From this survey, the potential of magnetic composites integrated with plasmonic metals is highlighted for light-induced water treatment and purification. Highlights: (1) Perspective of magnetic properties combined with plasmon metal attributes; (2) Overview of recent methods for magnetic silver-integrated composite synthesis; (3) Critical view of recent applications for photocatalytic pollutant removal.  相似文献   
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