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Purpose  

The apparent synovial hypertrophy in some cases of noninflammatory knee osteoarthritis suggests that total synovectomy may provide beneficial inflammatory and pain relief after total knee arthroplasty. The aim of the study was to compare the effect of synovectomy on the postoperative pain, bleeding and functional outcome after surgical treatment of knee osteoarthritis.  相似文献   
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We report the experience of a case of acute stroke in a patient affected by Rendu Osler syndrome and atrial fibrillation. The combination of dynamic computerized tomography perfusion scans and the use of a high-compliance balloon allowed increasing the treatment window for intra-arterial recanalization over 6 h after stroke onset in a patient with middle cerebral artery occlusion.  相似文献   
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BACKGROUND: Oxidative stress (OS) may result in damage to critical macromolecules, and an association between lead (Pb) toxicity and OS is a matter of research. Therefore, the aim of the present study was to investigate the effect of Pb on the oxidative system in indirectly Pb-exposed male apprentices. METHODS: Established parameters of Pb toxicity (aminolevulinic acid dehydratase index [ALAD index], zinc-protoporphyrin [ZPP]) as well as Pb-level in blood were determined in Pb-exposed apprentices (n > 25) and controls (n > 24). Enzymatic (glutathione peroxides [GPx], superoxide dismutase [SOD], catalase [CAT]) and non-enzymatic (alpha-tocopherol, beta-carotene) indices of OS, and malondialdehyde (MDA) level were also determined. RESULTS: There was a statistically significant increase in Pb level, ALAD index, ZPP concentration, GPx activity and MDA concentration in Pb-exposed apprentices when compared to controls. Although a statistically significant decrease in alpha-tocopherol and beta-carotene levels was seen, SOD and CAT activities were unaltered in Pb-exposed apprentices. Pb level and duration of Pb exposure were correlated with each other, as well as various indices of OS and MDA concentration. CONCLUSIONS: Chronic indirect Pb exposure results in lipid peroxidation in erythrocytes of apprentices via OS, and duration of Pb exposure is a reliable marker of Pb toxicity.  相似文献   
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Ozden O  Park SH  Kim HS  Jiang H  Coleman MC  Spitz DR  Gius D 《Aging》2011,3(2):102-107
A fundamental observation in biology is that mitochondrial function, as measured by increased reactive oxygen species (ROS), changes significantly with age, suggesting a potential mechanistic link between the cellular processes governing longevity and mitochondrial metabolism homeostasis. In addition, it is well established that altered ROS levels are observed in multiple age-related illnesses including carcinogenesis, neurodegenerative, fatty liver, insulin resistance, and cardiac disease, to name just a few. Manganese superoxide dismutase (MnSOD) is the primary mitochondrial ROS scavenging enzyme that converts superoxide to hydrogen peroxide, which is subsequently converted to water by catalase and other peroxidases. It has recently been shown that MnSOD enzymatic activity is regulated by the reversible acetylation of specific, evolutionarily conserved lysine(s) in the protein. These results, suggest for the first time, that the mitochondria contain bidirectional post-translational signaling networks, similar to that observed in the cytoplasm and nucleus, and that changes in lysine acetylation alter MnSOD enzymatic activity. In addition, these new results demonstrate that the mitochondrial anti-aging or fidelity / sensing protein, SIRT3, responds to changes in mitochondrial nutrient and/or redox status to alter the enzymatic activity of specific downstream targets, including MnSOD that adjusts and/or maintains ROS levels as well as metabolic homeostatic poise.  相似文献   
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