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Four cases of Hurthle cell tumor were examined by scanning electron microscopy after being macerated to remove all soluble components. By all morphological criteria, Hurthle cells are oncocytes with their usual augmented complement of mitochondria. The Hurthle cell mitochondria either are ovate with central stacks of cristae or elliptical or rod-like with cristae that often are finger-like. As in salivary gland oncocytes, the shelf-like cristae are anchored to the inner boundary membrane by tubular necks. In some Hurthle cells, all of the mitochondria exhibit reticulate cristae. A few mitochondria harbor a globular inclusion in their inner compartment. The Golgi apparatuses are relatively simple, consisting of imbricated saccules that are edged by small, bud-like structures. The rare lumina in the midst of clusters of Hurthle cells are lined by numerous microvilli. Thus, scanning electron microscopy of macerated Hurthle cell tumors has revealed a number of features, especially of their mitochondria, that have escaped detection by transmission electron microscopy.  相似文献   
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Objective:To investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric medicine.Methods:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant extract.For the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),orally.This w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or non-mortality.Incision wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under anesthesia.The first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,respectively.Results:The percentage yield of the extract was 49.80%w/w dry matter.The phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,perpenoids.saponins,steroids,proteins,and carbohydrates.The LD_(50) was beyond our experimental limit and was not determined.Increased concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,P0.05) healing effect on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:These data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine.  相似文献   
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Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury.  相似文献   
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New technologies have been developed around the world to tackle current emergencies such as biowaste recycling, renewable energy production and reduction of environmental pollution. The thermochemical and biological conversions of waste biomass for bioenergy production release solid coproducts and byproducts, namely biochar (BC), hydrochar (HC) and digestate (DG), which can have important environmental and agricultural applications. Due to their physicochemical properties, these carbon-rich materials can behave as biosorbents of contaminants and be used for both wastewater treatment and soil remediation, representing a valid alternative to more expensive products and sophisticated strategies. The alkylphenols bisphenol A, octylphenol and nonylphenol possess estrogenic activity comparable to that of the human steroid hormones estrone, 17β-estradiol (and synthetic analog 17α-ethinyl estradiol) and estriol. Their ubiquitous presence in ecosystems poses a serious threat to wildlife and humans. Conventional wastewater treatment plants often fail to remove environmental estrogens (EEs). This review aims to focus attention on the urgent need to limit the presence of EEs in the environment through a modern and sustainable approach based on the use of recycled biowaste. Materials such as BC, HC and DG, the last being examined here for the first time as a biosorbent, appear appropriate for the removal of EEs both for their negligible cost and continuously improving performance and because their production contributes to solving other emergencies, such as virtuous management of organic waste, carbon sequestration, bioenergy production and implementation of the circular economy. Characterization of biosorbents, qualitative and quantitative aspects of the adsorption/desorption process and data modeling are examined.  相似文献   
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