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BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
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Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro.  相似文献   
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Of 141 hospital survivors after intracardiac repair of tetralogy of Fallot, eight died suddenly 6–23 years later. Compared with the other 133 patients, these eight were older at operation, with higher post-repair systolic right ventricular pressure and more often complete atrioventricular block; ventricular arrhythmia was diagnosed before death in three cases. In follow-up totalling 2255 patient years, the linearized rate of sudden death was 0.35%/year. The instantaneous risk of sudden death showed continuous increase with the length of follow-up. Of 80 survivors electrocardiographically evaluated 13–26 (median 20) years postoperatively, none had complete block, but 79 had complete right bundle branch block, including seven with left anterior hemiblock. Ventricular extrasystoles were recorded in 1% at rest, in 34% during exercise and in 83% during 24-hour ambulatory monitoring, with Lown Grade ≥II in 27%. Old age and possibly presence of fibrosis and/or fibroelastosis in right ventricular outflow tract muscle correlated independently with high Lown Grade. A patient with Lown grade III died suddenly 2 years after our follow-up. Old age at repair thus was associated with increased risk of late sudden death and with frequent ventricular arrhythmia in long-term survivors.  相似文献   
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Strict environmental concern, depletion, and price hike of building construction materials are driving scientific studies for the search of alternative materials for building construction. To this end sustainable building materials could be a fruitful solution. This review aims to discern the environmental efficacy of solid waste management (SWM) and its relationship with four stimuli i.e., economic structure, regulatory structure, science, and time. The study also highlights the investigation of governance network to figure out the regulatory structure and governance of waste management. Extensive details on solid waste with their sources, recycling potential and their current utilization for substantial development are outlined. A throughout of the production process, properties, advantages, disadvantages, and the global economy of building material developed through recycling of solid waste are discussed. This article also deals with the sustainability, social, and environmental impact of green building materials. The study identifies the future direction for the effective utilization of solid waste for developing building materials. Further, the scope of the present also focusses on the concept of circular economy for developing construction materials through recycling of solid waste, which provides an easy reference for solid waste processing towards sustainability.  相似文献   
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We hypothesized that administration of clonidine would decrease the hypocapnic apnoeic threshold (HAT) and widen the CO2 reserve during non-REM sleep.  相似文献   
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