865 resultados para Delphi Technique


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The in situ saphenous vein bypass has been introduced in our department since 1989. A total of 26 bypasses in 22 patients have been followed prospectively. Indications for revascularisation have been severe arterial insufficiency in 73% of the cases (stage III or IV). With the exception of one postoperative death (myocardial infarction), all the patients have recovered uneventfully, with a regression to stage I. No amputation has been necessary. Morbidity has been 30%, with mainly minor local complications. The primary patency rate is 83% at one year and 78% after 2 and 3 years, whereas the secondary patency rate is 91% at one year, and remains constant thereafter up to 3 years. Considering our results and those from the literature, we believe that the in situ technique is very valuable, especially for below-knee vascular reconstruction. Technical difficulties of the method are analysed.

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The complexing capacity of synthetic (0.011 M tartrate in 13.5% ethanol) and real wine (Raimat Abadia) in titrations with added total Zn concentrations up to 0.03 M has been determined following the free Zn concentrations with AGNES (absence of gradients and Nernstian equilibrium stripping) technique. A correction to find the preconcentration factor or gain (Y1) really applied at each one of the ionic strengths reached due to Zn additions along the titration has been applied. The standard implementation of AGNES to real wine led to the observation of two anomalous behaviors: (a) an increasingly negative current in the deposition stage (labeled as “HER” effect) and (b) a minimum in the currents of the stripping stage plot (labeled as the “dip” effect). A practical strategy to apply AGNES avoiding the dip effect has been developed to quantify properly free Zn concentrations. The van den Berg–Ružic–Lee linearization method (assuming the existence of just 1:1 complexes) has been adapted to consider the dilution effect and the ionic strength changes. Aggregated stability constants and total ligand concentrations have been calculated from synthetic and wine titration data. The found complexing capacity in the studied wine (cT,L = 0.0179 ± 0.0007 M) indicates the contribution of ligands other than tartrate (which is confirmed to be the main one).

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OBJECTIVES: In some countries, nicotine-containing electronic cigarettes (e-cigarettes) are considered a consumer product without specific regulations. In others (eg, Switzerland), the sale of e-cigarettes containing nicotine is forbidden, despite the eagerness of many smokers to obtain them. As scientific data about efficacy and long-term safety of these products are scarce, tobacco control experts are divided on how to regulate them. In order to gain consensus among experts to provide recommendations to health authorities, we performed a national consensus study. SETTING: We used a Delphi method with electronic questionnaires to bring together the opinion of Swiss experts on e-cigarettes. PARTICIPANTS: 40 Swiss experts from across the country. OUTCOME MEASURES: We measured the degree of consensus between experts on recommendations regarding regulation, sale, use of and general opinion about e-cigarettes containing nicotine. New recommendations and statements were added following the experts' answers and comments. RESULTS: There was consensus that e-cigarettes containing nicotine should be made available, but only under specific conditions. Sale should be restricted to adults, using quality standards, a maximum level of nicotine and with an accompanying list of authorised ingredients. Advertisement should be restricted and use in public places should be forbidden. CONCLUSIONS: These recommendations encompass three principles: (1) the reality principle, as the product is already on the market; (2) the prevention principle, as e-cigarettes provide an alternative to tobacco for actual smokers, and (3) the precautionary principle, to protect minors and non-smokers, since long-term effects are not yet known. Swiss authorities should design specific regulations to sell nicotine-containing e-cigarettes.