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Risk is a concept inherent in every medical procedure. It can be defined as the probability of an adverse event in a defined population over a specified period of time. In the frame of food allergy management, it might be related to a diagnostic procedure, a treatment, or the consumption of foods. The risk of an adverse event can also be augmented by individual factors. This rostrum article discusses various aspects faced by children with food allergies in the light of risk, and their practical implications. Identifying personal risks for severe reaction, such as unstable asthma, and correcting them whenever possible also contribute to a reduction of the risk inherent to food allergy. Among the facets discussed, oral food challenges (OFC) are the most common diagnostic procedures implying an inherent risk. The risk of OFCs can be minimized by correct indication and timing of the test, a safe setting, as well as by ensuring that the patient is otherwise well without potential stressor potentially increasing the risk of a more severe reaction. Oral immunotherapy (OIT) has been studied as a potential treatment for increasing the threshold dose for reaction, and thus reducing the risk of accidental reaction. Nevertheless, the procedure is not devoid of risk as the patients may and do often react during the course of the procedure. Ingestion of trace amounts in processed foods, mainly in community settings such as restaurants, schools, or day care, represents a potential risk of reactions, although for a minority of patients. Precautionary allergen labeling (PAL) is a widespread strategy to reduce the potential risk of reactions due to traces. However, PAL is currently inefficient due to inconsistent labeling, also not indicating a clear maximum amount possibly present in the manufactured food. Finally, cost-effectiveness needs to be considered in risk management, as many risk reduction procedures are clearly not cost-effective.  相似文献   
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In the focal infarction model of the rat middle cerebral artery (MCA), the thalamus of the occluded side becomes gradually atrophic, mainly because of retrograde degeneration. We determined whether basic fibroblast growth factor (bFGF) administered intracisternally could prevent this thalamic atrophy. We occluded the left MCA through a small cranial opening, and animals were then divided into two groups. One group received intracisternal injections of recombinant bFGF (1 microgram dissolved in 0.1 ml of saline with 2% rat serum) starting 1 day after occlusion and repeated once a week to a total dose of 4 micrograms by four injections. The other group received vehicle solution by the same schedule. The animals were perfused and fixed at 28 days after occlusion, and histological examination was made at the level of the caudoputamen and thalamus. In the bFGF-treated rats, the area of the posterior ventral thalamus of the occluded side was 93% of that of the contralateral side, i.e., significantly larger than in the normal saline-treated rats (75%, p less than 0.01). The infarction size was not statistically different in the two groups. Microscopic observation indicated that normal-saline-treated animals showed shrinkage and disappearance of thalamic neurons, whereas bFGF-treated groups showed preservation of thalamic neurons. Computerized analysis of the cell size substantiated this observation. To assess the effect of bFGF on astrocytes, bFGF or vehicle solution was injected into normal rats, and their histology was evaluated at 1, 2, and 4 weeks after injection. The bFGF-injected group showed a significant increase in glial fibrillary acidic protein-positive astrocytes in the brain tissue facing the ventriculocisternal system.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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To elucidate the effect of fibroblast growth factor on the phenotypical conversion of fibroblasts to mesothelial cells, both immunohistochemical and ultrastructural examinations were carried out on cultured spheroids that were composed of fibroblasts obtained from the parietal pleura of rats with and without addition of antifibroblast growth factor receptor antibody. In the present study, antifibroblast growth factor receptor antibody was employed to block the effect of the autocrine component of fibroblast growth factor in the culture medium. Phenotypical conversion from fibroblast to mesothelial cells was clearly blocked in the experimental group, to which culture medium had been added with antifibroblast growth factor receptor antibody, whereas the control group, cultured without addition of antifibroblast growth factor receptor antibody, showed phenotypical conversion of fibroblasts that was confirmed by the development of macula adherens, microvilli, and positive expression of cytokeratin. These results indicate the possibility that fibroblast growth factor plays a key role in the process of phenotypic conversion of fibroblasts to regenerated mesothelial cells.  相似文献   
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A minute small-cell lung cancer measuring 8 x 5 mm was detected and serially imaged by computed tomography for about a year preceding resection. Although this solid nodule showed a short overall doubling time (76 days), the growth curve included an early phase without apparent growth prior to the phase of rapid growth. Accordingly, lung cancer cannot be ruled out when a small nodule (<10 mm) does not enlarge in the first several months of computed tomographic follow-up.  相似文献   
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Summary A new method for the direct determination of hippuric acid (HA) and o-, m- and p-methylhippuric acids (MHAs) in the urine, metabolites of toluene and o-, m- and p-xylenes by high performance liquid chromatography (HPLC) is described. A stainless-steel column packed with silica gel having dinitrophenyl residue and a mixed solution of methanol/water/acetic acid (80/20/0.2) containing tetra-n-butylammonium bromide (0.2% w/v) as mobile phase was used. Concentrations of HA and MHAs were estimated from their peak height at a wave length of 225 nm. Urine can be analyzed directly without solvent extraction or pretreatment to obtain complete separation of HA and o-, m- and p-MHAs. Urine samples from male workers exposed to toluene or xylenes were analyzed for HA or MHAs. The urinary levels of HA and MHAs increased by exposure to toluene and xylenes in proportion to the environmental concentrations of the solvents, although there is a considerable variation in metabolite concentrations. The slope of regression line between toluene and HA and that between m-xylene and m-MHA were similar. The urinary concentrations of HA and MHAs corresponding to 100 ppm (TLV) of toluene was 2.35 g/g creatinine and that of m-MHA corresponding to 100 ppm (TLV) of m-xylene was 2.05 g/g creatinine. The warning levels of the urinary metabolite concentrations of a group of workers and that of an individual worker corresponding to TLV of organic solvent concentration is discussed.  相似文献   
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To establish a unified classification system for mandibular osteomyelitis, various diagnostic terms were critically assessed and clinicopathologic findings of the lesions were carefully reviewed. We recommend classifying mandibular osteomyelitis into bacterial osteomyelitis and osteomyelitis associated with the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. Other diagnostic terms were excluded because they were not appropriate for classification. Diagnostic criteria for bacterial osteomyelitis are suppuration and osteolytic change. The lesions are easily cured by antibiotic treatments. Mandibular osteomyelitis in SAPHO syndrome is characterized by nonsuppuration and a mixed pattern on radiography, with solid type periosteal reaction, external bone resorption, and bone enlargement. The presence of osteomyelitis in other bones, arthritis, or skin diseases (palmoplantar pustulosis, pustular psoriasis, and acne) strongly suggests this syndrome. Antibiotic therapy is usually ineffective and the symptoms of SAPHO syndrome are often persistent.  相似文献   
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The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination.  相似文献   
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