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A number of methods allowing the detection of low levels of KRAS mutations have been developed in the last years. However, although these methods have become increasingly sensitive, they can rarely identify the mutated base directly without prior knowledge on the mutated base and are often incompatible with a sequencing‐based read‐out desirable in clinical practice. Here, we present a modified version of the ice‐COLD‐PCR assay called Enhanced‐ice‐COLD‐PCR (E‐ice‐COLD‐PCR) for KRAS mutation detection and identification, which allows the enrichment of the six most frequent KRAS mutations. The method is based on a nonextendable chemically modified blocker sequence, complementary to the wild‐type (WT) sequence leading to the enrichment of mutated sequences. This assay permits the reliable detection of down to 0.1% mutated sequences in a WT background. A single genotyping assay of the amplification product by pyrosequencing directly following the E‐ice‐COLD‐PCR is performed to identify the mutated base. This developed two‐step method is rapid and cost‐effective, and requires only a small amount of starting material permitting the sensitive detection and sequence identification of KRAS mutations within 3 hr. This method is applied in the current study to clinical colorectal cancer samples and enables detection of mutations in samples, which appear as WT using standard detection technologies.  相似文献   
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It took more than ten years from the initial mandate to the first implementation of e-toile, the Geneva health information exchange. Although most actors quickly agreed on the goals and potential benefits of such a system, obstacles were many, and mostly non-technical. The transparency resulting from a streamlined exchange of information may improve the continuity, quality and efficiency of care, while, at the same time, reveal and challenge habits and practices of care professionals and of citizens. This tension must be understood, and trust must be fostered amongst stakeholders. In our experience, key enablers were the collaborative elaboration and negotiation of an eHealth law, the definition of an eHealth strategy, as well as the involuntary increased financial pressure on all healthcare stakeholders. Nevertheless, and even though it is often cited as a successful model, the Swiss health system, being highly fragmented and based on a complex interplay of private and public stakeholders, is not as conducive to the deployment of eHealth systems as most other developed countries.  相似文献   
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Objective

The aim of this study is to observe the effects of dark chocolate on endothelial function after a series of successive apnea dives in non-thermoneutral water.

Methods

Twenty breath-hold divers were divided into two groups: a control group (8 males and 2 females) and a chocolate group (9 males and 1 female). The control group was asked to perform a series of dives to 20 m adding up to 20 min in the quiet diving pool of Conflans-Ste-Honorine (Paris, France), water temperature was 27 °C. The chocolate group performed the dives 1 h after ingestion of 30 g of dark chocolate. Flow-mediated dilatation (FMD), digital photoplethysmography, nitric oxide (NO), and peroxynitrite ONOO?) levels were measured before and after each series of breath-hold dives.

Results

A significant decrease in FMD was observed in the control group after the dives (95.28 ± 2.9 % of pre-dive values, p < 0.001) while it was increased in the chocolate group (104.1 ± 2.9 % of pre-dive values, p < 0.01). A decrease in the NO level was observed in the control group (86.76 ± 15.57 %, p < 0.05) whereas no difference was shown in the chocolate group (98.44 ± 31.86 %, p > 0.05). No differences in digital photoplethysmography and peroxynitrites were observed between before and after the dives.

Conclusion

Antioxidants contained in dark chocolate scavenge free radicals produced during breath-hold diving. Ingestion of 30 g of dark chocolate 1 h before the dive can thus prevent endothelial dysfunction which can be observed after a series of breath-hold dives.  相似文献   
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PURPOSE OF THE REVIEW: Infective causes of severe haemoptysis have progressively shifted to causes related to chronic inflammatory lung diseases. Physicians should, however, recognize the most common of them, for example necrotizing parenchymal infections, tuberculosis and mycetoma. RECENT FINDINGS: The recent increase in the incidence of a devastating Panton-Valentine leukocidin-associated staphylococcal pneumonia has reminded us of the crucial role of prompt diagnosis and management. General supportive care should be administered to prevent asphyxiation in addition to starting appropriate antibiotics as soon as possible. Once the bleeding has been controlled, the diagnostic strategy should integrate a detailed medical history, physical examination, Gram stain of the respiratory specimens and chest radiograph. Computed tomography scan has dramatically improved the diagnosis and the treatment of infective causes of severe haemoptysis by assessing the cause and mechanism(s) of haemoptysis. Although bronchial arteries are the major source of bleeding, nonbronchial systemic and pulmonary arteries' involvement should be feared, especially in haemoptysis related to tuberculosis and mycetoma. SUMMARY: Endovascular therapy should be first attempted to control the bleeding and then elective surgery performed in case of localized lesion and adequate pulmonary function. Fibreoptic bronchoscopy with broncho-alveolar lavage remains the cornerstone of diagnosis in immunocompromised hosts with haemoptysis and in the rare cases of alveolar haemorrhage related to infectious diseases.  相似文献   
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