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51.
P53 gene mutations in pleuropulmonary blastomas   总被引:1,自引:0,他引:1  
Pleuropulmonary blastoma (PPB) is rarechildhoodtumororiginating fromeitherlung orpleura. Although several cytogenetic changes, such as trisomy 2, trisomy 8, and loss of 17p material, have been reported, evidence of gene mutations is still lacking. Pathologically, PPB shares similarities with rhabdomyosarcoma in which p53 mutations are frequently detected. Possible implication of p53 mutations in PPB was investigated. PPBs of 3 patients were analyzed for occurrence of p53 mutations by using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method, and the nature of mutations was confirmed by direct sequencing. Two PPBs were confirmed to harbor p53 mutations. One was a Val to Leu substitution at codon 173, and another was a ArgArg to TrpCys substitution at codons 282 and 283. In each tumor, only the mutated allele was detected, suggesting inactivation of p53. Both patients with mutations had fatal outcome, while the remaining patient in whom no mutation was detected is disease free for 3 years after completion of treatment. The results raise the possibility that p53 inactivation can occur as a nonrandom genetic change involving the pathogenesis and outcome of PPB. Further studies in a larger series are necessary to clarify these matters.  相似文献   
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Background Conscious sedation using monitored anesthesia care can provide a clinical spectrum from relaxation to moderate anesthesia. This middle ground between general anesthesia and pure tumescent liposuction can help facilitate patient comfort and surgical proficiency during the procedure.Objective To describe a method of liposuction surgery with monitored anesthesia care in which a designated licensed and qualified individual is responsible for administration of supplemental intravenous conscious sedation as well as continuous monitoring of the patient.Methods Conscious sedation is induced with midazolam, and the patient is titrated to level II-V on the Ramsey sedation scale with propofol. The basic surgical technique is that of tumescent liposuction. However, the supplemental conscious sedation allows the tumescent fluid to be infiltrated at higher rates and fat extraction to be completed in a shorter period with minimal or no discomfort.Results In the authors experience with more than 5,000 cases of liposuction surgery using this method, safety and efficacy have been proved. No patients have experienced significant adverse effects.Conclusion Tumescent liposuction surgery with monitored anesthesia care provides a middle ground between general anesthesia and purely tumescent liposuction.  相似文献   
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Aims To assess the cost‐effectiveness of the CARE‐SHAKTI harm reduction intervention for injecting drug users (IDUs) over a 3‐year period, the impact on the cost‐effectiveness of stopping after 3 years and how the cost‐effectiveness might vary with baseline human immunodeficiency virus (HIV) prevalence. Design Economic cost data were collected from the study site and combined with impact estimates derived from a dynamic mathematical model. Setting Dhaka, Bangladesh, where the HIV prevalence has remained low despite high‐risk sexual and injecting behaviours, and growing HIV epidemics in neighbouring countries. Findings The cost per HIV infection prevented over the first 3 years was US$110.4 (33.1–182.3). The incremental cost‐effectiveness of continuing the intervention for a further year, relative to stopping at the end of year 3, is US$97 if behaviour returns to pre‐intervention patterns. When baseline IDU HIV prevalence is increased to 40%, the number of HIV infections averted is halved for the 3‐year period and the cost per HIV infection prevented doubles to US$228. Conclusions The analysis confirms that harm reduction activities are cost‐effective. Early intervention is more cost‐effective than delaying activities, although this should not preclude later intervention. Starting harm reduction activities when IDU HIV prevalence reaches as high as 40% is still cost‐effective. Continuing harm reduction activities once a project has matured is vital to sustaining its impact and cost‐effectiveness.  相似文献   
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Noninvasive positive pressure ventilation has been demonstrated to be of benefit in preventing endotracheal intubation and reducing mortality in specific patients in the setting of acute exacerbations of chronic obstructive pulmonary disease. The successful application of noninvasive positive pressure ventilation depends on a multitude of factors, including patient selection, choice of interface, physician experience, and patient-ventilator synchrony. The use of clinical practice guidelines has been shown to improve the process and outcomes of care. This paper presents a guideline for the use of noninvasive positive pressure ventilation in the setting of acute ventilatory failure in patients with acute exacerbations of chronic obstructive pulmonary disease.  相似文献   
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