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701.
BackgroundCholangiocarcinoma is a very aggressive tumor with poor survival. Therefore, early diagnosis and surgical resection are of paramount importance. Its diagnosis is difficult because access to the tumor is not easy. Biopsy is possible only for intrahepatic cholangiocarcinoma, which accounts for 10% of cases. Routine brush cytology from endoscopic retrograde cholangiopancreatography (ERCP) has a high specificity of 100% but unfortunately a low sensitivity of 30%. In this review we briefly describe new diagnostic techniques applicable to ERCP brush cytology specimens and targeting the genetic background of the disease, in particular fluorescence in situ hybridization (FISH) and digital image analysis (DIA).Date SourcesThe PubMed database up to 2011 was used for the retrieval of relevant articles. The search terms FISH, fluorescence in situ hybridization, DIA, digital image analysis and cholangiocarcinoma were used. Both original and review articles were used.ResultsFISH identifies cells with chromosomal abnormalities, mainly numerical aberrations, using a mixture of fluorescence-labeled probes. FISH offers a higher sensitivity than routine cytology, retaining a high level of specificity. The DIA criterion for malignancy is demonstration of aneuploidy. This technique increases the sensitivity to 40%, but the specificity remains low. Preliminary data from application to other tumors suggest that combination of FISH and DIA may be of further benefit.ConclusionsThe new techniques offer a significantly enhanced diagnostic efficacy in the evaluation of ERCP brush specimens. Apart from contributing to a more timely diagnosis, their wider application to cholangiocarcinoma may also facilitate the genetic study of the disease and add to our understanding of oncogenesis at the molecular level, with the prospect of identifying targets for novel therapeutic interventions.  相似文献   
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Aim: To evaluate the potential benefits of introducing universal rotavirus (RV) vaccination in Greece. Methods: A decision analytic model was developed to compare the burden and cost of rotavirus gastroenteritis (RVGE) with and without a universal RV vaccination (88% vaccination coverage) for a cohort of children followed from birth until the age of five. Results: Universal RV vaccination would substantially decrease the RVGE burden on the National Health System by reducing RVGE‐related hospitalizations/emergency visits and medical consultations by 83% and 75%, respectively. Total RVGE‐related costs was estimated at about 7.6 M€ and would be reduced by 5.9 M€ (?78%) if RV vaccination was introduced. A rapid effect is expected with 76% of cases and 84% of costs avoided would be averted within 2 years postvaccine introduction. The societal benefit would also be significant: total annual number of RVGE cases and parent’s lost work days would be reduced by 67% and 78%, respectively. Including indirect costs, the total disease cost reduction would be 9 M€. Conclusion: Introduction of universal RV vaccination in Greece could offer considerable medical and economic benefits for the National Health System and society. Potential herd immunity would improve results in favour of vaccination.  相似文献   
704.
Aortic stenosis (AS) is the most common type of valvular heart disease in the elderly. Surgical aortic valve replacement (SAVR) has been the standard practice for treating severe, symptomatic AS, but recently new treatment options have emerged. Transcatheter aortic valve replacement (TAVR) is now an established treatment option in patients at high surgical risk. In this review, we focus on recent developments and compare the two treatment methods in specific populations in terms of efficacy and safety (e.g., in patients with history of prior thoracic surgery, type of anesthesia employed, access site used or need for permanent pacing). The impact of comorbidities (pulmonary hypertension, arterial hypertension and obesity paradox), the cost-effectiveness of TAVR vs. SAVR and advances in transcatheter valve technology as well as issues that merit further investigation are further discussed. Moreover, outcomes and complications of TAVR in patients of different risk category (extremely high, high, intermediate and low risk) are analyzed. We strongly believe that during the following years, TAVR may evolve as the treatment of choice in a broader group of patients with symptomatic AS and beyond those with intermediate and high-risk features.  相似文献   
705.
Transcatheter alcohol septal ablation (ASA) treatment of symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM) is based on the existence and degree of intraventricular obstruction. Patients with significant gradient and symptoms who do not respond to optimal medical therapy are eligible to gradient reduction through a surgical (septal myectomy) or a transcatheter (alcohol septal ablation) septal reduction. The latter encompasses occlusion of a septal branch perfusing the hypertrophied septum, which is involved in the generation of obstruction, by injecting ethanol into the supplying septal branch(es). ASA has been established as a highly effective and safe method and has outnumbered the surgical gold standard. Although the technique is straightforward, patient selection and some technical details may influence the efficacy and safety of the procedure. The technique is based on echocardiographic contrast guidance, which allows accurate target septal branch selection and optimisation of the result. Published long-term results from high-volume centres have confirmed the effectiveness of ASA and have shown excellent survival, which is comparable to that in the general population. Choice and performance of the surgical or interventional treatment should be implemented in highly specialised centres in terms of a heart-team approach, taking notice of anatomic characteristics as well as comorbidities. Involvement of all cases in international registries may reveal the individual merits and indications for the surgical and interventional treatment in HOCM.  相似文献   
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In this work, we present a generic multi-period integrated infrastructure planning and operational scheduling approach for developing energy systems. The methodology is applicable to energy systems with multiple resources, locations, processing pathways, and planning periods in which infrastructure decisions can be carried out. The framework incorporates a graph based approach to mode based scheduling, in which the mode transitions are mapped to a directed graph. We illustrate the applicability and effectiveness of the overall framework through the use of a case study examining the long-term development of a multi-site energy-intensive hydrogen based energy system in Texas. In the case study, we find that developing the energy system over the course of its operational life as opposed to the beginning of its operational life reduces its capital and operational cost by over 20%.  相似文献   
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