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41.
DA Moneret-Vautrin F Rance G Kanny A Olsewski JL Gueant G Dutau L Guerin 《Canadian Metallurgical Quarterly》1998,28(9):1113-1119
BACKGROUND: The increase in frequency of peanut allergy and fatal cases have been reported. OBJECTIVES: The objective of this study is to document the severity of food allergy to peanuts by evaluating the reactive dose of peanuts and to search for the role of peanut oil. METHODS: This study is carried out on the basis of 142 observations collected according to the same diagnostic methodology in two allergy centres in France. Skin-prick-tests were performed with peanut powder, peanut oil and peanut oil proteinic extract. Labial provocation tests were performed on 121 patients. The reactive dose of peanuts and the role of peanut oil were determined by standardized oral provocation tests in 50 and 62 patients respectively. The data are computerized and the data bank includes 509 food allergic patients. RESULTS: Allergy to peanuts represents 28% of food allergies and occurs under 1 year of age in 46% of cases, under 15 years of age in 93%. The clinical features were atopic dermatitis (40%), angioedema (37%), asthma (14%), anaphylactic shock (6%) and digestive symptoms (1.4%). The specific IgE were class 3 or higher in 80% of cases. The total reactive dose was less than 100 mg in 25% of cases, from 100 mg to 1 g in 62.5%. All patients reacted to a dose of less than 7.1 g. The threshold of peanut reactivity was lower than the threshold of egg reactivity. An allergy to peanut oil was demonstrated in 14 patients. CONCLUSION: The severity of peanut allergy and the early onset of the occurrence of this allergy is documented. The role of residual allergenic proteins in peanut oil is established by positive skin-prick tests to proteic extracts from peanut oil and by double-blind placebo-controlled challenges to peanut oil. The increased consumption of allergens in the form of peanut oil and fats can contribute to the occurrence or persistence of symptoms and may be suspected to increase the risk of sensitisation. 相似文献
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DA Steeber ML Tang XQ Zhang W Müller N Wagner TF Tedder 《Canadian Metallurgical Quarterly》1998,161(12):6638-6647
Lymphocyte migration into lymphoid organs is regulated by adhesion molecules including L-selectin and the beta7 integrins. L-selectin and alpha4beta7 are predominantly hypothesized to direct the selective migration of lymphocytes to peripheral lymph nodes and the gut-associated lymphoid tissues, respectively. To further characterize interactions between L-selectin and beta7 integrins during lymphocyte recirculation, mice deficient in both receptors (L-selectin/beta7 integrin-/-) were generated. The simultaneous loss of L-selectin and beta7 integrin expression prevented the majority of lymphocytes (>95% inhibition) from attaching to high endothelial venules (HEV) of Peyer's patches and other lymphoid tissues during in vitro binding assays. Moreover, the inability to bind HEV eliminated the vast majority of L-selectin/beta7 integrin-/- lymphocyte migration into Peyer's patches during short-term and long-term in vivo migration assays (>99% inhibition,p < 0.01). The lack of lymphocyte migration into Peyer's patches correlated directly with the dramatically reduced size and cellularity (99% reduced) of this tissue in L-selectin/beta7 integrin-/- mice. High numbers of injected L-selectin/beta7 integrin-/- lymphocytes remaining in the blood of wild-type mice correlated with markedly increased numbers of circulating lymphocytes in L-selectin/beta7 integrin-/- mice. Loss of either L-selectin or the beta7 integrins alone resulted in significant but incomplete inhibition of Peyer's patch migration. Collectively, the phenotype of L-selectin/beta7 integrin-/- mice demonstrates that these two receptors primarily interact along the same adhesion pathway that is required for the vast majority of lymphocyte migration into Peyer's patches. 相似文献
43.
CY Pai TS Kuo TJ Jaw E Kurant CT Chen DA Bessarab A Salzberg YH Sun 《Canadian Metallurgical Quarterly》1998,12(3):435-446
The Extradenticle (Exd) protein in Drosophila acts as a cofactor to homeotic proteins. Its nuclear localization is regulated. We report the cloning of the Drosophila homothorax (hth) gene, a homolog of the mouse Meis1 proto-oncogene that has a homeobox related to that of exd. Comparison with Meis1 finds two regions of high homology: a novel MH domain and the homeodomain. In imaginal discs, hth expression coincides with nuclear Exd. hth and exd also have virtually identical, mutant clonal phenotypes in adults. These results suggest that hth and exd function in the same pathway. We show that hth acts upstream of exd and is required and sufficient for Exd protein nuclear localization. We also show that hth and exd are both negative regulators of eye development; their mutant clones caused ectopic eye formation. Targeted expression of hth, but not of exd, in the eye disc abolished eye development completely. We suggest that hth acts with exd to delimit the eye field and prevent inappropriate eye development. 相似文献
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Extensive N‐methylation of chitosan: evaluating the effects of the reaction conditions by using response surface methodology 下载免费PDF全文
Tonimar DA Senra Danilo M Santos Jacques Desbrières Sergio P Campana‐Filho 《Polymer International》2015,64(11):1617-1626
The effects of reaction time, concentration of aqueous sodium hydroxide and molar ratio iodomethane/chitosan on the yield of the reaction of chitosan with iodomethane in N‐methyl‐2‐pyrrolidone (NMP) at 25.0 ± 0.1 °C, as well as on the characteristics of the resulting N,N,N‐trimethylchitosan (TMCh), were evaluated by using full‐factorial 23 design analysis and response surface methodology. This study also aimed to determine the reaction conditions allowing the production of water‐soluble TMCh presenting a high average degree of quaternization and intrinsic viscosity at high reaction yield. 1H NMR spectroscopy was employed for structural characterization, including the determination of average degrees of acetylation () and quaternization (), while capillary viscometry was used to determine intrinsic viscosity [η]. The results show that when the extensive N‐methylation is carried out for 24 h in NMP/15% NaOH (w/v) employing a lower excess of iodomethane (CH3I/Ch = 9), water‐soluble highly substituted ( = 46.0%) TMCh ([η] = 213.0 mL g?1) can be produced in high yield (81.8%). The highly significant mathematical models resulting from this study describe the dependence of the experimental responses on the reaction conditions and allow the characteristics and properties of the resulting TMCh to be defined by properly choosing the reaction conditions. © 2015 Society of Chemical Industry 相似文献
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短程反硝化以其碳源消耗量、废污泥产量、温室气体排量极低及无需曝气等优势,被认为是最具研究潜势的厌氧氨氧化底物供给技术,成为近年来研究热点。本文首先介绍了短程反硝化工艺原理;其次从污泥源、反应时间、碳源类型、碳源量及pH等5个方面总结了影响短程反硝化工艺启动因素;随后综述了短程反硝化耦合厌氧氨氧化工艺的重要研究进展,同时指出了耦合工艺实验研究与工程应用的不足,并提出了解决实验与工程应用缺陷的方案;最后展望了耦合工艺处理城市污水和工业硝酸盐废水的可行性及应用前景,认为全面分析工业硝酸盐废水化学组分与基于分子生物学水平的宏基因组学测序、元转录组学技术是未来耦合工艺同步处理城市污水和工业硝酸盐废水的研究重点。 相似文献
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