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A comparative study of an O2-diffusion cathode and a H2-diffusion anode has been performed to ascertain the limiting processes, when they are combined in a flow alkaline fuel cell with hydroperoxide ion generation. The linear sweep voltammograms and the impedance diagrams of both electrodes show large differences. The cathode reaction is charge transfer-controlled up to current densities of at least 1 A cm?2, whereas the dissociative adsorption, charge transfer and diffusion of H2 appear to limit the anode reaction. The anode, with limiting current densities of about 90 and 150 mA cm?2 for 1.0 and 6.0 M KOH, respectively, then clearly controls the hydroperoxide ion production in the fuel cell. Diffuse reflectance infrared Fourier transform spectroscopy and X-ray photoelectron spectroscopy reveal that, the carbon of the H2-diffusion anode does not undergo significant oxygen functionalisation during hydroperoxide ion generation in the fuel cell.  相似文献   
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We thank Dr Villata et al. for their thought-provoking comments.Their concern about the suitableness to choose combined endpointsin clinical trials deserves some comment.  相似文献   
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BACKGROUND: Although cyanoacrylate tissue adhesives are frequently used in the closure of cutaneous lacerations and excisions, only a few reports comment on their usefulness as a dressing over sutured wounds. A new formulation of octyl-2-cyanoacrylate (Liquid Bandage; BAND-AID, Johnson & Johnson) is used as an occlusive protective film over minor cuts and scrapes. OBJECTIVE: An uncontrolled pilot study to assess the safety, efficacy, and cost of Liquid Bandage as an occlusive dressing over sutured facial excisions. METHODS: Patients undergoing excision of facial neoplasms were recruited. After conventional layered repair, Liquid Bandage was applied. On suture removal, the wounds were photographed and evaluated by three dermatologists, who assigned an overall outcome rating. The average cost of Liquid Bandage and routine wound care materials was calculated based on prices from three different pharmacies. RESULTS: Of the 18 wounds available at follow-up, 17 were assigned an overall outcome rating of good or excellent by at least one of the evaluators. Eleven wounds received an excellent rating from at least two of the evaluators. One case of distal flap necrosis occurred. Liquid Bandage proved to be less expensive than routine postsurgical wound care materials. CONCLUSIONS: Liquid Bandage dressing is safe and effective over sutured facial excisions.  相似文献   
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In this study, we analyzed the spatiotemporal expression patterns of the high-molecular weight (MAP2a and b) and low-molecular weight (MAP2c and d) cytoskeletal microtubule-associated protein-2 (MAP2) isoforms with Western blotting, and the cellular localization of the high-molecular weight MAP2 isoforms with immunocytochemistry in the hippocampi of 1- to 21-day-old rats. Moreover, the temporal profile (from 30 min to 1 week) of MAP2 isoform reactivity to kainic acid-induced status epilepticus was studied in P9 rats. During development, the expression of the high-molecular weight MAP2 isoforms significantly increased, while the low-molecular weight isoforms decreased, the most prominent changes occurring during the second postnatal week. This developmental increase in the high-molecular weight MAP2 expression was also confirmed with immunocytochemistry, which showed increased immunoreactivity, particularly in the molecular layers of the dentate gyrus, and in CA1 and CA3 stratum radiatum. In 9-day-old rats, status epilepticus resulted in a rapid transient increase (about 210%) in the high-molecular weight MAP2 expression, without any effect on the low-molecular weight MAP2. Moreover, disturbed dendritic structure in the CA1 and CA3 stratum radiatum was manifested as formation of varicosities 3h after the kainic acid treatment. The strictly developmentally regulated MAP2 isoform expression suggests different functional roles for these proteins during the postnatal development in the rat hippocampus. Moreover, high-molecular weight MAP2s may play a role in nerve cell survival during cell stress.  相似文献   
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Objectives  

This study was designed to assess the prevalence of adverse drug reactions (ADRs) in the internal medicine wards of two teaching Hospitals, identify the most common ADRs, the principal medications involved, and determine the risk factors implicated in the occurrence of such ADRs.  相似文献   
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OBJECTIVE: To describe the optimal surgical strategy in heart specimens with transposition of the great arteries (TGA) and left ventricular outflow tract obstruction (LVOTO). METHODS: Thirty-three specimens with LVOTO were selected: TGA with intact ventricular septum (TGA/IVS) (10), TGA/VSD (21), and Taussig-Bing (2). RESULTS: LVOTO in TGA/IVS consisted of combinations of bicuspid pulmonary valve (four), subpulmonary fibrous ridge (four), obstructive muscular conus (two) and bulging muscular septum (four). Arterial switch operation (ASO) with LVOTO resection/valvotomy was feasible in nine hearts. Obstructive anterior papillary muscle prohibited LVOTO relief in one specimen. In TGA/VSD and Taussig-Bing LVOTO consisted of combinations of bicuspid (nine) or unicommissural (one) pulmonary valve, fibrous ridge (three), obstructive muscular conus (five), malaligned outlet septum (six), accessory mitral valve tissue (two), straddling mitral valve (two) and anterior mitral valve rotation (four). VSDs were subpulmonary in 13 (9 perimembranous, 4 muscular), subaortic in 3 (2 perimembranous, 1 anterior muscular), doubly committed in 2, inlet in 3 (2 perimembranous, 1 muscular), non-committed and anterior in 1, and finally 1 VSD extended both into inlet and subpulmonary outlet septum. LVOTO resection and ASO with VSD closure was possible in 10. In six specimens, both a Rastelli and a Nikaidoh operation were feasible. For two hearts, a Nikaidoh procedure was the only option, while Rastelli was considered optimal in another specimen. Mitral valve anomalies prevented LVOTO relief in four, only permitting for Senning/VSD closure (one) or univentricular palliation (three). CONCLUSIONS: LVOTO resection and pulmonary valvotomy frequently permits an ASO. Inlet VSD, impossibility of VSD enlargement, straddling mitral valve, distant aorta and small right ventricle make the Nikaidoh procedure the best option. Mitral anomalies preventing LVOTO relief can make biventricular repair impossible.  相似文献   
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