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61.
IgE-mediated contact urticaria syndrome (CUS) is one of the manifestations of allergy in childhood atopic dermatitis (AD). Allergens such as foods and animal products penetrate the skin easily. They can then cause urticarial reactions in sensitized individuals. A provocation test system for foods, called the skin application food test (SAFT), has been developed. Over more than 5 years, a group of 175 patients with AD was built-up and investigated in a prospective follow-up study with SAFT. SAFT was more frequently positive in AD children aged 6–2 years than in older children. In several children of this population (Group 1), we repeated SAFT within a period of 1 year. In another unrelated group of children (Group 2–1), we compared the results of 'original' SAFT and SAFT using square chambers (Van der Bend) or Silver patches. In the 3rd group (Group 2–2) we compared'original' SAFT with SAFT using big Finn Chambers. The agreement between the tests was high: in Group 1, we observed 88 to 93% concordant scores, and in Group 2, the scores were 96% to 100%. Statistically, the K coefficient ranged from 0.71–0.87 in Group 1, and from 0.83–1.00 in Group 2. SAFT is therefore highly reproducible. Agreement was at least 88% between the scores (the lowest K value observed was at least 0.71).  相似文献   
62.
BACKGROUND: Food allergies are an important cause of life-threatening hypersensitivity reactions. Oral tolerance can be considered the default immune response to dietary antigens, with immune deviation resulting in allergic sensitization. However, primary sensitization to food allergens may not solely be through the gastrointestinal mucosa, as strong T-helper type 2 (Th2)-biased immunity can result from exposure to protein allergens on barrier-disrupted skin. OBJECTIVE: The purpose of this study was to examine whether exposure to allergens through the skin may interfere with the normal development of oral tolerance and promote allergic sensitization to food proteins. METHODS: Female BALB/c mice were exposed epicutaneously to peanut protein and induction of systemic oral tolerance through high dose feeds of peanut protein was subsequently assessed. Other mice were rendered tolerant prior to epicutaneous peanut exposure. Sensitivity to peanut was determined by assessing delayed-type hypersensitivity, proliferative, cytokine and antibody responses. RESULTS: Epicutaneous exposure to peanut protein induced potent Th2-type immunity with high levels of IL-4 and serum IgE. Primary skin exposure prevented the subsequent induction of oral tolerance to peanut in an antigen-specific manner. Upon oral challenge, mice became further sensitized and developed strong peanut-specific IL-4 and IgE responses. Furthermore, animals with existing tolerance to peanut were partly sensitized following epicutaneous exposure. CONCLUSION: Epicutaneous exposure to peanut protein can prevent induction of oral tolerance, and may even modify existing tolerance to peanut. Epidermal exposure to protein allergens selectively drives Th2-type responses, and as such may promote sensitization to food proteins upon gastrointestinal exposure.  相似文献   
63.
The impacts of caffeic acid (3,4‐dihydroxycinnamic acid, CA) on the pharmacokinetics of levodopa (L‐dopa) were studied in rabbits. A single dose of 5/1.25 mg·kg?1 l ‐dopa/carbidopa was administered alone or was co‐administered with three different doses of caffeic acid (2.5, 5, and 10 mg·kg?1), or a single dose of 5 mg·kg?1 caffeic acid was administered alone via an intramuscular route to six rabbits each in a crossover treatment protocol. Plasma levels of l ‐dopa, 3‐O‐methyldopa (3‐OMD), caffeic acid, and ferulic acid were determined and subsequently used to calculate their pharmacokinetic parameters. The results indicated that caffeic acid administered at a dose of 10 mg·kg?1 decreased about 22% of the peripheral formation of 3‐OMD and about 31% of the Cmax of 3‐OMD. In addition, the metabolic ratios (MR, AUC of 3‐OMD/AUC of L‐dopa) decreased by about 22%. Results also indicated that caffeic acid significantly decreased the proportion of 3‐OMD (p < 0.05). In contrast, the parameters of neither caffeic acid nor ferulic acid were significantly affected by l ‐dopa/carbidopa. In conclusion, caffeic acid at a dose of 10 mg·kg?1 can significantly affect the COMT metabolic pathway of L‐dopa. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
64.
Background: Studies have shown that socioeconomic groups differ in their dietary behaviours, and it has been suggested that these differences partly account for health inequalities between social groups. To-date, however, we have a limited understanding of why socioeconomic groups differ in their dietary behaviours. This paper addresses this issue by examining the relationship between socioeconomic status, food preference (likes and dislikes) and the purchase of 'healthy' food (i.e. food consistent with dietary guideline recommendations). Methods: This study was based on a dual-sample, dual-method research design. One sample was systematically selected from the Australian Commonwealth electoral roll and the data collected using a mail-survey methodology (81% response rate, n =403). The second consisted of a convenience sample of economically disadvantaged people recruited via welfare agencies (response rate unknown, n =70). A mail survey methodology was deemed inappropriate for this sample, so the data were collected by personally delivering the questionnaire to each respondent. Results: Socioeconomic groups differed significantly in their food purchasing choices and preferences. The food choices of respondents in the welfare sample were the least consistent with dietary guideline recommendations, and they reported liking fewer healthy foods (all results were independent of age and sex). Notably, socioeconomic differences in preference explained approximately 10% of the socioeconomic variability in healthy food purchasing behaviour. Conclusion: Whilst it is not clear why socioeconomic groups differ in their food preferences, possible reasons include: reporting bias, differential exposure to healthy food as a consequence of the variable impact of health promotion campaigns, structural and economic barriers to the procurement of these foods, and subculturally specific beliefs, values, meanings, etc.  相似文献   
65.
食品中铬元素的含量分析   总被引:2,自引:0,他引:2  
目的:了解常见食品中铬的含量,指导人群合理摄取铬元素,对糖尿病、动脉粥样硬化、冠心病患者的合理膳食提供理论依据。方法:用石墨炉原子吸收分光光度法测定25种食品中铬含量。选用357.9μm波长,采用二步干燥。测定回收率为92.6%--98.1%,相关系数r=0.9987,回归方程Y=0.0l19C 0.0766。结果:肉、蛋类中铬含量在102—532μg/kg之间,谷、豆和坚果类铬含量在104.1—355μg/kg之间,蔬菜、水果类铬合量在35.8—214.7μg/kg之间。结论:铬含量以动物性食品最高,谷类食物居中,蔬菜、水果较低。  相似文献   
66.
Objective: To evaluate the effectiveness of Coca-Cola in enhancing the absorption of itraconazole. Methods: Eight healthy volunteers were randomized to receive two treatment sequences in a two-way crossover design with a 1-week wash-out period separating each study treatment. Treatment I, the control, consisted of 100 mg itraconazole with 325 ml water. Treatment II was identical to treatment I, except that itraconazole was administered with 325 ml of Coca-Cola (pH 2.5). Results: Serum itraconazole concentrations, after administration with Coca-Cola (treatment II), were higher than after administration with water (treatment I). The mean AUC was 1.12 vs 2.02 μg · h · ml−1, the mean Cmax was 0.14 vs 0.31 μg · ml −1and the mean tmax was 2.56 vs 3.38 h in treatments I and II, respectively. Conclusion: The absorption of itraconazole can be enhanced by Coca-Cola. Received: 4 November 1996 / Accepted in revised form: 21 January 1997  相似文献   
67.
Objective: To describe the development and reproducibility of a self‐report instrument, for use with children in years 4–6, to identify sources of food eaten during the day, and type and frequency of food purchases at school. Design: Tool development stages included formulation of content and format, expert review, piloting and a test–retest study. Subjects/setting: The pilot study included school students (n = 20) in years 4 and 5 (seven girls, mean age 9.7 ± 0.7 years) attending an Australian public primary school. The test–retest study was performed in a large metropolitan public primary school (n = 245 children, 52% female, mean age 10.7 ± 0.91 years) including children from years 4 (n = 88), 5 (n = 84) and 6 (n = 73). Statistical analysis: A Kappa statistic was used to assess level of agreement between the two time periods separated by 1 week. The results were analysed using SAS version 8.2 with each question compared at time 1 and 2. Results: The mean kappa was 0.529 using pairings from 17 questions. Values ranged from 0.18 to 0.71 (CI 0.46–0.60). Conclusions and applications: The School Eating Habits and Lifestyle Survey has been developed and pilot‐tested in primary school‐aged children and shown to have moderate stability over time. The results show that each phase of development, particularly those spent in consultation and testing, led to progressive improvement of this instrument. This process improved the quality of information produced and gave insights to self‐report of dietary intake and behaviours among children.  相似文献   
68.
目的通过对甘肃农产区居民的饮食习惯、营养知识和态度的调查,从需方的角度对开展面粉营养素强化的可行性进行探讨。方法采用定性和定量调查相结合的方法,对4个地区的城市和农村的男性和女性分别进行现状和原因的调查分析。结果被调查地区多数城市(92.7%)和农村(60.7%)家庭日常饮食以面食为主,94.7%的城市家庭购买面粉,而在农村地区,多数家庭自己种植或购买小麦。城市居民较农村对营养和维生素有更多的了解和关注。农村男性对面粉营养素强化持怀疑态度,女性更加关注孩子的营养,认为目前的饮食单一,孩子可能营养不足。结论与农村地区相比,城市地区的社会经济条件和知识基础较利于开展面粉强化工作。  相似文献   
69.
70.
《Nutrition reviews》1986,44(10):327-328
Giving foods as rewards can enhance consumption of those foods, while giving rewards to induce consumption of foods can decrease subsequent consumption of those foods.  相似文献   
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