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71.
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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Laparoscopic Heller cardiomyotomy and Dor fundoplication is the surgical procedure of choice for esophageal achalasia. The aim of our study was to investigate the clinical outcome and safety of laparoscopic Heller–Dor procedure performed by using Hook electrocautery and as a teaching module for advanced laparoscopic surgery. Between January 2005 and December 2010, 25 consecutive patients with achalasia underwent laparoscopic Heller–Dor operation by a single surgeon. All the patients received upper gastrointestinal series (barium swallow), esophagogastroscopy, and esophageal manometry to exclude esophageal carcinoma and to confirm the diagnosis. All the patients were operated by laparoscopic modified Heller myotomy with Dor fundoplication by using hook electrocautery. Among 25 operated patients, 14 were male and 11 were female with a median age of 43 years (range 18–72 years). The mean operative time was 93.3 min (range 50–50 min), the mean operative blood loss was 90 ml (range 40–200 ml), the median time to oral feeding was 2 days (2–4 days), and the median hospital stay was 4 days (4–7 days). There was no conversion to open surgery. Intraoperative mucosal perforation was encountered in three patients and was repaired in all of them by laparoscopic suture. All the patients had an uneventful recovery without postoperative complication and had excellent clinical response (96 %) during follow-up. Laparoscopic Heller–Dor operation using hook electrocautery is safe, inexpensive, and effective treatment for achalasia which is useful for teaching and training surgical residents in advanced laparoscopic surgery.  相似文献   
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Intramedullary interlocking nailing is the gold standard for treatment of tibial shaft fractures.The growing use of intramedullary nailing has resulted in an increased number of tibial nailing in daily...  相似文献   
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Inferior vena cava filters are commonly encountered devices on diagnostic imaging that were highlighted in a 2010 Food and Drug Administration safety advisory regarding their complications from long-term implantation. The Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE) trial is an ongoing after-market study investigating the safety and utility of commonly utilized filters in practice today. While most of these filters are safe, prompt recognition and management of any filter-associated complication is imperative to prevent or reduce the morbidity and mortality associated with them. This review is aimed at discussing the appropriate utilization and placement of inferior vena cava filters in addition to the recognition of filter-associated complications on cross-sectional imaging. An overview of the PRESRVE trial filters is also provided to understand each filter's propensity for specific complications.  相似文献   
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