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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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To evaluate whether treatment with a mitogenic agent may increase bone formation and bone mass in osteopenia induced by estrogen deficiency, we determined the effect of oral fluoride treatment on bone and bone cells in ovariectomized rats. Sodium fluoride (NaF) was administered to 3-month-old ovariectomized rats 1 day after ovariectomy (OVX) for 1, 3, and 6 months. NaF was given in drinking water at the dose of 1 mg/kg body weight per day. Fluoride administration led to a partial prevention of the bone loss induced by OVX as shown by histologic analysis of tibial metaphysis and by evaluation of femoral calcium content. These beneficial effects of fluoride were more striking at early time points (1 and 3 months postovariectomy) than after 6 months of treatment. The increase in trabecular bone volume in OVX rats treated with fluoride was associated with a rise in the osteoblast surface, which was increased by 60, 72, and 235% at 1, 3, and 6 months postovariectomy compared to untreated OVX rats. In OVX rats and in sham-operated rats plasma osteocalcin was increased in correlation with the osteoblast surface. However, these two parameters were not correlated in OVX rats treated with fluoride. The heat-labile bone-specific alkaline phosphatase in plasma was decreased in OVX rats treated with fluoride compared to OVX rats, suggesting that both the number and the activity of osteoblasts were affected by NaF treatment. To examine the effect of fluoride on the osteocalcin production and the proliferative capacity of bone cells, osteoblastic cells were isolated by collagenase digestion from the bone surface of tibia in treated and untreated OVX rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Traditionally, psychotherapy groups for children included only relatively intact youngsters. This paper describes a group consisting of four (near) psychotic children and two co-therapists which met for over three years. The developmental changes which occurred in the group over the course of time will be identified and discussed using a neo-psychoanalytic, object relations framework.  相似文献   
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The purpose of this article is to describe the extent to which certified nurse-midwives (CNMs) provide care to vulnerable populations in the United States and the source of reimbursement for this care. The data were obtained from the first phase of a national study to address the characteristics of women served and cost of care provided by CNMs. Results were analyzed nationally and by American College of Nurse-Midwives regions. Certified nurse-midwives in all types of practices are providing care to women from populations that are vulnerable to poorer than average outcomes of childbirth because of age, socioeconomic status, refugee status, and ethnicity. Ninety-nine percent of CNMs report serving at least one group of vulnerable women, and CNMs in the inner city and rural practices serve several groups. The vast majority of CNMs are salaried; only 11% receive their primary income from fee-for-service. Fifty percent of the payment for CNM services is from Medicaid and government-subsidized sources whereas less than 20% comes from private insurance. Source of income varies by type of setting in which the CNM attends births. The results suggest that CNMs, as a group, make a major contribution to the care of vulnerable populations.  相似文献   
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Abstract: varicella is a common childhood disease with a typical exanthem. We present four children with severe, localized disease, all associated with some form of trauma to the skin during the incubation period: a 3½-year-old boy sustained wasp stings on the hand, a 5-year-old boy received extensive sun exposure, a neonate had latrogenic trauma to her arm, and a 13-year-old boy underwent knee arthroscopy and was wearing a cast. It is postulated that such injuries to the skin either allowed more virus-infected cells to enter the skin at the sites, or that factors such as insect venom and ultraviolet light altered local immunity to varicella zoster virus.  相似文献   
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