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Much attention is now being focused on foods from genetically modified plants because of the risk of allergenicity. No such risk has been reported for the first generation of GM plants made resistant to herbicides and insect larvae. Current experiments with hypoallergenic GM plants are reported and discussed in the present paper. The second generation of GM plants will improve the nutritional aspects of natural foods. Transgenic proteins could reach from 4 up to 8% of the total protein content in these foods. Any potential difference in allergenicity between second generation GM plants and the natural varieties must be examined with respect to the risk for food allergy caused by food products made from these plants and the risk for respiratory allergies in the people living near the crops caused by airborne pollen originating from the plants. WHO–FAO directives as well as the Codex Alimentarius proposals and the European Food Safety Authority (EFSA) guidelines recommend that transgenic proteins be screened for homology (by in silico study) and cross-reactivity with known allergens, as well as being examined carefully for modifications of host-plant proteomes. In vivo animal studies are also to be carried out to assess any potential immunogenicity. Lacking adequate safety data, the absence of potential allergenicity of transgenic plants cannot be ruled out. This is why data that do not meet the recommended safety criteria required for commercialization of GM plants do not allow us to rule out absolutely the risk that may be associated with products that are going to be commercialized. Therefore, it is essential that commercialized GM plants be monitored. We propose the establishment of public reference serum banks based on up-to-date WHO–FAO recommendations concerning the selection of sera according to precise criteria. We also propose establishing a system of allergovigilance linking national and European health and food safety agencies and a network of university hospital-based clinical and laboratory reference centres, together with a network of clinical allergists, responsible for the creation of the serum banks. Allergists working through these networks would be able to identify new sensitizations to transgenic foods in the population, just as they now identify new types of food allergies, which, in this case, would be GM foods. Such a project is now being established in France.  相似文献   
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In economic evaluations of health technologies, health outcomes are commonly measured in terms of quality‐adjusted life years (QALYs). QALYs are the product of time and health‐related quality of life. Health‐related quality of life, in turn, is determined by a social tariff, which is supposed to reflect the public's preference over health states. This study argues that, because of the tariff's role in the societal decision‐making process, it should not be understood as merely an operational (statistical) definition of health, but as a major instrument of democratic participation. I outline what implications this might have for both the method used to aggregate individual preferences, and the set of individuals whose preferences should count. Alternative tariff specifications and decision rules are explored, and future research directions are proposed.  相似文献   
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Anterior cingulate cortex (ACC), a key brain region involved in cognitive control and decision making, is suggested to mediate effort- and value-based decision making, but the specific role of ACC in this process remains debated. Here we used frontal midline theta (FMT) and the reward positivity (RewP) to examine ACC function in a value-based decision making task requiring physical effort. We investigated whether (1) FMT power is sensitive to the difficulty of the decision or to selecting effortful actions, and (2) RewP is sensitive to the subjective value of reward outcomes as a function of effort investment. On each trial, participants chose to execute a low-effort or a high-effort behavior (that required squeezing a hand-dynamometer) to obtain smaller or larger rewards, respectively, while their brainwaves were recorded. We replicated prior findings that tonic FMT increased over the course of the hour-long task, which suggests increased application of control in the face of growing fatigue. RewP amplitude also increased following execution of high-effort compared to low-effort behavior, consistent with increased valuation of reward outcomes by ACC. Although neither phasic nor tonic FMT were associated with decision difficulty or effort selection per se, an exploratory analysis revealed that the interaction of phasic FMT and expected value of choice predicted effort choice. This interaction suggests that phasic FMT increases specifically under situations of decision difficulty when participants ultimately select a high-effort choice. These results point to a unique role for ACC in motivating and persisting at effortful behavior when decision conflict is high.  相似文献   
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Autism is recognized as an additional diagnosis possible in people with Down syndrome. This pathology is still rarely detected and treated in this population in France. This article is a review of the English literature and of studies led during the last fifteen years. Studies have identified the expression of autism clinical signs in children with Down syndrome and the sensitivity and specificity of diagnostic instruments for autism in this population despite their cognitive impairments. This paper emphasizes authors’ recommendations about intervention taking into account the dual diagnosis: they encourage the identification of autism as well as early and appropriate intervention for those children whose needs differ from their peers without comorbid disorder. These results show the need to educate professionals about the importance of the detection of autism in children with Down syndrome, and the prevention that could follow.  相似文献   
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