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101.
102.
The objective of the present study is to propose guidelines to ensure safe practice in teaching centres while allowing endoscopic sinonasal surgery (ESS) training to proceed. A prospective complications audit of ESS procedures was undertaken over a 5‐year period (January 1996–December 2000). The results have been used to form specific guidelines for safe and effective ESS training. A total of 500 patients underwent ESS during the 5‐year period. The senior author was the main surgeon in 55% of cases with the trainee observing or assisting. A supervised trainee was the main surgeon in 45% of cases. The overall complication rate was 1.2% (n = 6) (i.e. 0.7% for the 815 procedures performed). These were all minor complications. We encountered no major complications in 500 patients over the 5‐year period. This audit shows that training need not compromise patient safety provided it is phased and structured. We propose appropriate phases and suggest the minimum requirements for units involved in ESS training.  相似文献   
103.
Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) significantly accelerates progression to allograft cirrhosis. Current biochemical parameters to monitor progression of chronic HCV after OLT have yielded low specificity and sensitivity. Here we investigated the HCV-specific immunity and serum levels of soluble CD30 (sCD30), a novel marker of Th2 immunity, in patients with and without allograft cirrhosis. Patients with hepatic inflammation but no cirrhosis (HIN, n=20) revealed elevated serum interferon (IFN)-gamma and high frequency of IFN-gamma producing CD4 T(h1) cells compared to those with hepatic cirrhosis (HFC, n=20) that had high interleukin (IL)-5 and IL-5 producing CD4 T(h2) cells. Patients with HFC, but not HIN, were found to have significantly higher levels of sCD30. Therefore, we conclude that lack of optimal Th1-type CD4 T cells is associated with HCV-induced allograft cirrhosis. Further, sCD30 may represent a novel marker for surveillance of hepatic cirrhosis in transplant recipients with chronic HCV infection.  相似文献   
104.
105.
Tympanosclerosis (TS) is a common sequelae of chronic otitis media found in all age groups. Over a period of 3 years, out of 520 surgical cases, 68 (13%) were found to have varying amounts of Tympanosclerotic plaques (TSP) warranting surgical removal. 60% had extension of TSP over the ossicular chain thus affecting its mobility. Deliberate surgical removal of TSP was undertaken for hearing improvement. Systematic and meticulous removal of TSP rather than en-bloc removal has been found to improve the hearing as close to as in, non-tympanosclerotic ear surgery.  相似文献   
106.
107.
The purpose of this article is to report a case of esthesioneuroblastoma involving the bilateral paranasal sinuses, which was excised using an endoscopic-assisted transfacial approach. A patient presented with nasal swelling and left-sided nasal obstruction, epistaxis, and diplopia. Examination revealed broadening of the nasal dorsum with a fleshy pink mass in both nasal cavities. Computed tomographic scan showed a mass involving the nasal cavity and paranasal sinuses on both sides. The tumor was diagnosed as group C esthesioneuroblastoma. The mass was excised by bilateral medial maxillectomy and bilateral frontoethmoidectomy. Using a 0 degrees endoscope, the attachment of the tumor to the cribriform plate was identified and resected using a motordrill. On Waroff staining, Hispathology slides suggested esthesioneuroblastoma. The patient was asymptomatic for 1 year, following which he developed infection of the nasal cavity for which he had no form of treatment. He subsequently developed maggots in the nasal cavity after which he died. An endoscopic resection of the cribriform plate from the nasal cavity without a formal craniofacial resection can be safely performed with oncologic safety.  相似文献   
108.

Background  

Combined hepatocellular carcinoma and intrahepatic cholangiocarcinoma is a rare hepatobiliary malignancy incorporating components derived from both hepatocyte and intrahepatic bile duct epithelium. The natural history, treatment, and prognosis of this distinct cancer differ from hepatocellular carcinoma (HCC) or cholangiocarcinoma (CC) and are not completely understood. There is considerable controversy about the classification, treatment, and survival, which in turn is related to the rarity of the condition. Treatment options include surgical resection and the prognosis is believed to be better than CC but worse than HCC alone.  相似文献   
109.
Blunt traumatic cardiac rupture is associated with a high mortality rate. Motor vehicle accidents account for most cardiac ruptures, but crush injury is relatively rare. We describe a case of a 72-year-old man who had the left atrial appendage ruptured through blunt trauma due to a fall from scooter. Simple suture repair of the atrial appendage was achieved after clamping the base of the left atrium to control the bleeding. He recovered without complication. Traumatic injury to left atrial appendage is rarely seen and reported.  相似文献   
110.
Agricultural and industrial practices more than doubled the intrinsic rate of terrestrial N fixation over the past century with drastic consequences, including increased atmospheric nitrous oxide (N2O) concentrations. N2O is a potent greenhouse gas and contributor to ozone layer destruction, and its release from fixed N is almost entirely controlled by microbial activities. Mitigation of N2O emissions to the atmosphere has been attributed exclusively to denitrifiers possessing NosZ, the enzyme system catalyzing N2O to N2 reduction. We demonstrate that diverse microbial taxa possess divergent nos clusters with genes that are related yet evolutionarily distinct from the typical nos genes of denitirifers. nos clusters with atypical nosZ occur in Bacteria and Archaea that denitrify (44% of genomes), do not possess other denitrification genes (56%), or perform dissimilatory nitrate reduction to ammonium (DNRA; (31%). Experiments with the DNRA soil bacterium Anaeromyxobacter dehalogenans demonstrated that the atypical NosZ is an effective N2O reductase, and PCR-based surveys suggested that atypical nosZ are abundant in terrestrial environments. Bioinformatic analyses revealed that atypical nos clusters possess distinctive regulatory and functional components (e.g., Sec vs. Tat secretion pathway in typical nos), and that previous nosZ-targeted PCR primers do not capture the atypical nosZ diversity. Collectively, our results suggest that nondenitrifying populations with a broad range of metabolisms and habitats are potentially significant contributors to N2O consumption. Apparently, a large, previously unrecognized group of environmental nosZ has not been accounted for, and characterizing their contributions to N2O consumption will advance understanding of the ecological controls on N2O emissions and lead to refined greenhouse gas flux models.  相似文献   
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