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141.
In the present report, an environmentally benign magnetically recoverable nickel(ii)-based nanoreactor as a heterogeneous catalyst has been developed via a template free approach. The catalytic performance of the synthesized catalyst is assessed in the confined oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides under aerobic conditions. The salient features of our protocol include oxidant- and ligand-free conditions, use of water as a green solvent, room temperature and formation of nitrogen and water as the only by-products. Moreover, a broad range of functional groups are tolerated well and provide the corresponding diaryl sulfides in moderate to good yields. Moreover, the heterogeneous nature of the catalyst permits facile magnetic recovery and reusability for up to seven runs, making the present protocol highly desirable from industrial and environmental standpoints.

An environmentally benign nickel(ii)-based magnetic nanoreactor has been developed for oxidative coupling of arenethiols with arylhydrazines to form unsymmetrical diaryl sulfides in water at room temperature.  相似文献   
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Dynamic hip screw fixation is a commonly performed procedure for internal fixation of intertrochanteric femoral fractures.Arterial injury following the operative fixation is a rare but serious event.We...  相似文献   
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Simultaneous fracture/dislocation of the thumb carpometacarpal (CMC)joint and dislocation of the metacarpophalangeal (MCP)joint is considered as a rare injury pattern.We report an unusual case of dorsa...  相似文献   
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INTRODUCTIONTraumatic abdominal wall hernia (TAWH) is a rare entity. Most cases occur in children, following an injury from the bicycle handle bar. In adults, it usually results from road traffic accidents (RTA). We present one of the largest reported cases of TAWH following RTA managed by delayed mesh repair.PRESENTATION OF CASEA 35 yr old obese male with RTA was diagnosed with TAWH with 19 cm × 15 cm defect in left flank. As there were no intra abdominal injuries and overlying skin was abraded, he was planned for elective repair after 6 months. On exploration a defect of 30 cm × 45 cm was found extending from midline anteriorly to 8 cm short of midline posteriorly in transverse axis and costal margin to iliac crest in craniocaudal axis. After restoration of bowel into abdominal cavity, primary closure or even approximation of muscular defect was not possible thus a mesh closure using 60 cm × 60 cm prolene mesh in subcutaneous plane was done. After 4 months follow up, patient is healthy and has no recurrence.DISCUSSIONEmergent surgical management of TAWH is usually favoured due to high incidence of associated intra abdominal injuries. Delayed repair may be undertaken in selected cases.CONCLUSIONTAWH, although rare, should be suspected in cases of RTA with abdominal wall swellings. With time, the hernia defect may enlarge and muscles may undergo atrophy making delayed repair difficult.  相似文献   
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Background: Oral submucous fibrosis (OSF) involves large sections of population and is related to certain chewing practices that involve direct exposure of the gingiva to noxious chemicals and additives. The impact of such practices, although studied extensively in relation to the cheek mucosa, is not elucidated as far as gingival tissues are concerned. The possible DNA damage on affected gingiva is also one of the objectives of the present study. Methods: One hundred cases of individuals with OSF and 89 without OSF were examined for periodontal parameters and compared. Biopsies of gingival tissue from both categories were examined with conventional hematoxylin and eosin staining for epithelial, connective tissue, and inflammatory changes. Comet assay of epithelial cells obtained from scraping the gingival surface of both patients with OSF and control individuals was performed . Results: Patients with OSF had poorer oral hygiene and greater loss of attachment, probing depth, and recession compared with controls. Significant histopathologic changes in the form of loss of rete ridges with gingival epithelium reduced to a flattened surface was observed. All the patients with OSF showed comet cells in larger numbers. The controls also showed comet cells but in fewer numbers, and the number of individuals showing comet cells was significantly less. Conclusion: OSF showed significant changes in affected gingiva, and the presence of comet cells in all the patients with OSF is a significant indicator of possible pathognomonic developments.  相似文献   
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Habituation is a nonassociative learning mechanism, in which an initial response toward repeated stimuli gradually wanes. This is amongst the simplest and most widespread forms of behavioral plasticity. So far, neither the underlying molecular mechanisms nor the precise neural networks of habituation are well understood. We have developed a novel paradigm to quantify habituation of the olfactory jump reflex in Drosophila. We present data demonstrating several behavioral properties of this phenomenon, generally observed in other species. We also show that the dunce and rutabaga memory mutants behave abnormally in this assay, suggesting that this assay might be used in behavioral screens for new mutants with defects in this simpler form of behavioral plasticity.  相似文献   
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