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961.
962.
Interobserver reproducibility and agreement with original diagnosis in the categories “atypical” and “suspicious for malignancy” for bile and pancreatic duct brushings 下载免费PDF全文
963.
964.
Wen F Abdalla MY Aloman C Xiang J Ahmad IM Walewski J McCormick ML Brown KE Branch AD Spitz DR Britigan BE Schmidt WN 《Journal of medical virology》2004,72(2):230-240
Hepatitis C virus (HCV) and HCV core protein are hypothesized to induce hepatic oxidative stress and exacerbate injury caused by other toxins such as ethanol that induce the cytochrome P450 enzyme, CYP2E1. In the current study, the effects of HCV core protein [sequence genotype 1b, (nt 342-915)] on parameters indicative of oxidative stress were evaluated in HepG2 cells stably over expressing CYP2E1 (E47), or vector controls (C34). Stable (>10 passages) expression of HCV core protein and CYP2E1 was confirmed in clonal cell lines at the level of mRNA and immunoreactive protein. Prooxidant production, as determined by cellular oxidation of dichlorodihydrofluorescin and dihydroethidium (HE), was increased by expression of HCV core protein in the presence or absence of CYP2E1. Depletion of glutathione (GSH) with buthionine sulfoximine (BSO) enhanced prooxidant production in both C34 and E47 cells. In addition, prooxidant production was greater in BSO-treated cells expressing HCV core protein, and this effect was further enhanced in cells expressing both HCV core and CYP2E1. The CYP2E1 inhibitor, 4-methylpyrazole, could suppress increased prooxidant production in E47 cells. Finally, cells co-expressing both CYP2E1 and HCV core protein showed significantly decreased viability following GSH depletion. These studies show simultaneous expression of HCV core protein and CYP2E1 increases parameters indicative of oxidative stress as well as sensitization to cell injury induced by GSH depletion. These results support the hypothesis that enhanced injury in hepatocytes over expressing both HCV core protein and CYP2E1 is mediated by increases in oxidative stress. 相似文献
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966.
C. Schmidt M. Fronza M. Goettert F. Geller S. Luik E.M.M. Flores C.F. Bittencourt G.D. Zanetti B.M. Heinzmann S. Laufer I. Merfort 《Journal of ethnopharmacology》2009
Aim of the study
n-Hexanic and ethanolic extracts from twelve plants (Brugmansia suaveolens Brecht. et Presl., Eupatorium laevigatum Lam., Galinsoga parviflora Cav., Iresine herbstii Hook., Kalanchöe tubiflora Hamet-Ahti, Petiveria alliacea L., Pluchea sagittalis (Lam.) Cabrera, Piper regnellii DC., Schinus molle L., Sedum dendroideum Moç et Sessé ex DC., Waltheria douradinha St. Hill., Xanthium cavanillesii Schouw.) used in traditional South Brazilian medicine as wound healing agents were investigated in various biological assays, targeting different aspects in this complex process.Materials and methods
The extracts were investigated on NF-κB DNA binding, p38α MAPK, TNF-α release, direct elastase inhibition and its release as well as on caspase-3. Fibroblasts migration to and proliferation into the wounded monolayers were evaluated in the scratch assay, the agar diffusion test for antibacterial and the MTT assay for cytotoxic effects.Results
The hydrophilic extracts from Galinsoga parviflora, Petiveria alliacea, Schinus molle, Waltheria douradinha and Xanthium cavanillesii as well as the lipophilic extract of Waltheria douradinha turned out to be the most active ones.Conclusions
These results increase our knowledge on the wound healing effects of the investigated medicinal plants. Further studies are necessary to find out the effective secondary metabolites responsible for the observed effects. 相似文献967.
An unusual case of calcium pyrophosphate arthropathy (pseudogout) involving the temporomandibular joint of a 53-year-old woman presented clinically as an ear canal tumor. Further evaluation and surgical exploration disclosed chondrocalcinosis of the temporomandibular joint with involvement of the bones at the left base of the skull. This case report emphasizes the importance of recognizing the lesion by frozen-section examination because excellent results can be obtained by intraoperative curettage of the calcareous deposits and local irrigation with saline solution. 相似文献
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970.