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The present studies identify the steric factors involved in the hydration of epoxide intermediates of some pesticides by hepatic epoxide hydrolase. Investigations were carried out regarding the formation of reactive epoxide intermediates and their different interactions with the hepatic epoxide hydrolase. Some pesticides and their parent epoxides were selected on he basis of the steric hindrance on the oxirane ring. The results indicate that the inhibition of this enzyme depends on the steric hindrance produced by substituents on the oxirane ring of these pesticides. Mono- and di-substituted oxiranes are good substrates of the epoxide hydrolase and non-competitive inhibitors of the hydration of styrene oxide, while tri-substituted epoxides are virtually inactive on inhibiting the hepatic epoxide hydrolase activity. 相似文献
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Ristiniemi J Flinkkilä T Hyvönen P Lakovaara M Pakarinen H Biancari F Jalovaara P 《The Journal of trauma》2007,62(1):174-183
BACKGROUND: The healing of a metaphyseal fracture line is a major problem in cases of distal tibial fracture treated with external fixation. METHODS: Forty-seven distal tibial fractures treated with two-ring Ilizarov hybrid external fixation (16 AO/OTA type A and 31 type C, 10 open) were followed up. Fracture reduction and union time was evaluated and IOWA and RAND 36-Item Health Survey scores were used to assess functional outcome. RESULTS: Thirty-five fractures united uneventfully in a median time of 20 weeks, but 12 fractures needed additional procedures because of delayed union. According to univariate analysis, the risk factors for a longer time needed for fracture union were translational displacement and current smoking, and the risk factors for reoperation because of delayed union translational displacement fibular fracture fixation, and the number of cigarettes smoked per day. In multivariate analysis, translational displacement was a risk factor for both longer time to fracture union and reoperation and fibular fracture fixation was a risk factor for reoperation. If the translational displacement was less than 3 mm, the reoperation rate was 6%, whereas if the displacement was more than 3 mm, it was 83%. Reoperation was performed on 50% of the patients who underwent fibular fixation and on 15% of the patients who did not undergo fibular fixation. There were only marginal decreases in the range of motion and arthritis scores in the AO/OTA fracture types other than type C3. There were no significant differences in RAND 36 scores between the general Finnish population aged 18 to 64 years and our patients. CONCLUSIONS: Hybrid external fixation of distal tibial fractures is associated with delayed union, which is closely related to the degree of residual translational displacement after reduction. Fixation of an associated fibular fracture does not help to achieve better contact in the tibial fracture and increases the risk of delayed union. 相似文献
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Bixio Riccardo Bertelle Davide Pistillo Francesca Pedrollo Elisa Carletto Antonio Rossini Maurizio Viapiana Ombretta 《Clinical rheumatology》2022,41(4):1247-1254
Clinical Rheumatology - Myasthenia gravis is an autoimmune disease affecting the neuromuscular junction, often associated with other autoimmune diseases, including rheumatoid arthritis. Patients... 相似文献
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Alexandre Abizaid Mariano Albertal John Ormiston Hugo Londero Peter Ruygrok Ana Cristina Seixas Fausto Feres Luiz A Mattos Rodolfo Staico Roberto L Silva Mark Webster Jim Stewart Francisco Paoletti Tori Kataoka Peter Fitzgerald Amanda Sousa J Eduardo Sousa 《Catheterization and cardiovascular interventions》2005,66(4):491-495
The purpose of the study was to examine the safety and efficacy of two different formulations of mycophenolic acid (MPA)-eluting Duraflex stents on coronary de novo lesions. Recent data indicate that local delivery of MPA in the porcine overstretch coronary model significantly reduces neointimal hyperplasia (NIH). Patients were divided into three consecutive groups. The first (n=50) and second (n=55) groups received moderate- and slow-release MPA-eluting Duraflex stent, respectively. The last group (n=50) received the bare metal Duraflex stent. Clinical, angiographic, and intravascular ultrasound analysis were performed at 6-month follow-up. All stents were successfully deployed and patients were discharged home without clinical events. Compared to controls, 6-month in-lesion and in-stent minimum luminal diameter as well as late lumen loss were not significantly different in the moderate- and slow-release treatment groups. At follow-up, percentage obstruction and NIH volume were also similar between the three groups. At 30 days and 6 and 12 months, there were no differences noted between the three groups with respect to major adverse cardiac events as well as the individual rates of mortality, myocardial infarction, or repeat revascularization. There were no cases of subacute or late thrombosis. In this feasibility trial, the MPA-eluting Duraflex stents in either slow- or moderate-release formulations were well tolerated, but showed no benefit for treatment of coronary lesions when compared to controls. Further testing with different drug dosing or delivery rate might improve these results. 相似文献
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Antonio Piralla Ana Moreno Maria Ester Orlandi Elena Percivalle Chiara Chiapponi Fausto Vezzoli Fausto Baldanti the Influenza Surveillance Study Group 《Emerging infectious diseases》2015,21(7):1189-1191
Because swine influenza virus infection is seldom diagnosed in humans, its frequency might be underestimated. We report a immunocompromised hematologic patient with swine influenza A(H3N2) virus in 2014 in Italy. Local pigs were the source of this human infection. 相似文献