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Coeliac disease, also known as gluten-sensitive enteropathy or non-tropical sprue, is a relatively uncommon condition. The dietary presence of gliadin, an alcohol-soluble subfraction of gluten, in immunologically susceptible hosts will lead to small intestinal mucosal inflammation and subsequent mucosal villous atrophy which results in nutrient and vitamin malabsorption. The symptomatic presentations of patients with coeliac disease are related to this malabsorption process which can be reversed in the vast majority of patients with a gluten-free diet. 相似文献
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A monoclonal antibody against tetrodotoxin (TTX) was obtained from Balb/c mice immunized with TTX-bovine serum albumin (BSA) conjugate. The monoclonal antibody was highly specific for TTX and had no cross-reaction to tetrodonic acid, which is a TTX derivative, or gonyautoxins, although a minor cross-reaction to anhydro-tetrodotoxin was observed. The monoclonal antibody neutralized the lethal activity of TTX. By using the monoclonal antibody, a rapid and highly sensitive competitive enzyme immunoassay (EIA) for quantitative analysis of TTX was developed. By the competitive EIA system, TTX can be determined quantitatively in about 30 min (90 min are required if the time for preparation of the solid-phase antigen was included), and the working range for quantitative analysis of TTX was 2-100 ng/ml. In recovery tests and examinations of TTX samples, results of the mouse bioassay and EIA analyses correlated well (r = 0.987). Moreover, it was demonstrated that low concentrations of TTX, which could not be detected by the mouse bioassay, could be determined quantitatively by the competitive EIA. 相似文献
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Koichi Fujita Makiko Ikuzawa Tetsuo Izumi Takashi Hamano Yukimasa Mitsuhashi Yukio Matsuki Tadao Adachi Hiroko Nonogi Tazu Fuke Hideyo Suzuki Masatake Toyoda Yoshio Ito Masahiro Iwaida 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,168(3):206-211
Summary Considerable improvements were made to the original Rankine method. Replacement of aspiration with an injection system contributed a great deal to the simplification of procedure, being accompanied with an increase in reproducibility. Air (flow rate 1.01/min) was used for injection because the use of inert gas gave little increase in recovery rate.Sodium bisulphite (free sulphite) and three kinds of combined sulphite compound (bisulphite adducts of acetaldehyde, pyruvic acid and D-mannose) were used to find the most suitable conditions for the separate determination of free and combine sulphites.Free sulphite was expelled from the sample by bubbling at 0 °C for 30 min. It was confirmed that no combined sulphite was dissociated under these conditions. The phosphoric acid concentration had an important role in the liberation of sulphite. When 25% phosphoric acid was used, more than 99% of free sulphite was expelled by cold bubbling and more than 99% of combined sulphite was recovered by heating afterwards for 10 min.The scope of the modified Rankine method was also extended to the determination of sulphite in concentrated orange juice.
Studies on the Analyses of Sulphites in Foods (III) 相似文献
Verwendung der modifizierten Rankine-Methode zur getrennten Bestimmung von Sulfiten in Lebensmitteln. III
Zusammenfassung Die Rankine-Methode wurde bedeutend verbessert. Ein Umtausch der Aspiration mit Blasensystem trug beträchtlich zur Vereinfachung des Bestimmungsverfahrens bei, und die Reproduzierbarkeit wurde verbessert. Luft (Fließrate 1,01/min) wurde als Blasengas benutzt, da der Gebrauch von Inertgas für die Wiederfindungsrate unbedeutend ist.Natriumhydrogensulfit (freies Sulfit) und drei Arten gebundener Sulfite (Acetaldehydhydrogensulfit, Pyruvathydrogensulfit undd-Mannosehydrogensulfit) dienten dazu, die geeignetsten Bedingungen für die getrennte Bestimmung der freien und gebundenen Sulfite zu ermitteln.Freies Sulfit wurde bei 0 °C durch 30 min Durchblasen vertrieben. Hierbei ging kein gebundenes Sulîit verloren. Die Phosphorsäurekonzentration war wichtig für die Freisetzung des Sulfites. Wenn man 25%ige Phosphorsäure verwendet, werden > 99% freien Sulfites beim Durchblasen in der Kälte vertrieben, während > 99% gebundenen Sulfites durch nachheriges 10 min langes Erhitzen wiedergewonnen werden.Die modifizierte Rankine-Methode wurde weiterhin für konzentrierte Säfte verwendet.
Studies on the Analyses of Sulphites in Foods (III) 相似文献
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Escherichia coli penicillin-binding protein PBP3 is a key element in cell septation. It is presumed to catalyse a transpeptidation reaction during biosynthesis of the septum peptidoglycan but, in vitro, its enzymatic activity has only been demonstrated with thiolester analogues of the natural peptide substrate. It has no detectable transglycosylase activity with lipid II as substrate. This tripartite protein is constructed of an N-terminal membrane anchor-containing module that is essential for cell septation, a non-penicillin-binding (n-PB) module of unknown function and a C-terminal penicillin-binding (PB) module exhibiting all the characteristic motifs of penicilloyl serine transferases. The n-PB module, which is required for the folding and stability of the PB module, may provide recognition sites for other cell division proteins. Initiation of septum formation is not PBP3-dependent but rests on the appearance of the FtsZ ring, and is thus penicillin-insensitive. The control of PBP3 activity during the cell cycle is briefly discussed. 相似文献
69.
When the 11S globulin, one of the major storage proteins in soybean seeds (Glycine max), was heated at 0·5 ionic strength, the denaturation temperature was biologically estimated to be about 10 degrees higher than that at 0·1 ionic strength. The results also coincided well with those obtained by differential scanning calorimetry. The heat denaturation temperatures of the protein obtained by differential scanning calorimetry were estimated to be 78·1°C and 89·6°C at 0·1 and 0·5 ionic strength respectively. The enthalpies of heat denaturation were 2·0 cal/g and 3·2cal/g at 0·1 and 0·5 ionic strength, respectively. Correlation was not observed between the heat stability at high ionic strength and the content of the ordered secondary structure or a dissociation-association reaction of the protein with change of ionic strength. However, increase of the hydrophobic region at high ionic strength indicated the possibility of stabilisation of the quaternary structure of the 11S globulin by hydrophobic bonding during heat denaturation. 相似文献
70.
R Sakamoto ES Bennett VA Henry S Paragina T Narumi Y Izumi Y Kamei E Nagatomi Y Miyanaga H Hamano 《Canadian Metallurgical Quarterly》1993,34(13):3510-3514
PURPOSE: To examine the results of the phenol red thread tear test in a cross-cultural comparison. METHODS: Two groups of 500 controlled normal subjects who do not wear contact lenses from the United States and Japan were investigated. RESULTS: The mean wet length of the thread for the United States was 23.9 mm (SD 9.5 mm). The mean for Japan was 18.8 mm (SD 8.6 mm). There was a significant difference between the two countries (P < 0.05). Males subjects had significantly longer wet lengths than females for both countries (P < 0.05). There was a moderate correlation between right and left eye results for both countries. CONCLUSIONS: The phenol red thread tear test was found to be easy to administer. Results were in line with current knowledge and theories of the lacrimal system. Results also indicated that this test may disclose subtle differences not previously found with other tear tests. 相似文献