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Kirsten Skamstrup Hansen Stefan Vieths Helle Vestergaard Per Stahl Skov Carsten Bindslev-Jensen Lars K. Poulsen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,756(1-2)
The aim of the study was to investigate the possibility of a seasonal variation in reactivity to apples in 27 birch pollen allergic patients. Before and during the birch pollen season 1998, the patients were subjected to double-blind, placebo-controlled food challenges (DBPCFCs) with grated fresh Golden Delicious apple followed by an open food challenge with whole fresh apple. The clinical reactions elicited during the challenges were evaluated both by the patients and the investigators. Moreover, the skin reactivity and the in vitro reactivity to apple were evaluated by skin prick test (SPT), leukocyte histamine release (HR), measurement of specific IgE, and immunoblotting experiments. The sensitivity of the DBPCFC, when compared with the result of the open challenge, was 0.74 (14/19) before the season and 0.80 (16/20) during the season. None of the patients reacted to the blinded challenge without a subsequent reaction to the open challenge. One placebo reaction was registered both before and in season, but not in the same patient. The patient scores of the first positive challenges, and the maximal scores of each combined blinded and open challenge session, were significantly increased during the pollen season (P<0.05). The scores of the open challenge were significantly higher than the scores of the DBPCFC both before the season and during the in-season challenges (P<0.05). Specific IgE against Golden Delicious increased during season (P<0.05), while neither SPT, HR, nor immunoblotting experiments could confirm an increase in reactivity. In conclusion, the results of the oral challenge tests indicated an increase in clinical reactivity to apples during the birch pollen season in birch pollen allergic individuals. 相似文献
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The occurrence of bikunin and ·1-microglobuli n was investigated in human ovary and Fallopian tubes. Bikunin and ·1-microglobulin are transcribed in the liver from a common gene. Bikunin immunoreactivity was detected in the zona pellucida.
A positive reaction for bikunin was also observed in connective tissue of the oviduct. In addition, mast cells showed a more
intense posi tive reaction than the surrounding connective tissue. Specific displaceable ·1-microglobulin immunoreactivity was revealed in the zona pellucida. The data suggest that bikunin and ·1- microglobulin are trapped in the zona pellucida.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
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Apolipoprotein E has key functions in lipoprotein metabolism, and polymorphisms in the apolipoprotein E gene are associated with distinct lipoprotein patterns. The possibility of gene-nutrient interactions for apolipoprotein E has been addressed in many studies. Although results have generally been mixed, the indications for such an interaction have been more common in studies employing a metabolic challenge. Studies directly designed to examine apolipoprotein E gene-nutrient interactions are needed. 相似文献
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Sampling and filtration efficiency of two commonly used plankton nets. A comparative study of the Nansen net and the Unesco WP 2 net 总被引:1,自引:1,他引:0
The paper presents the results from a study in which two commonlyused plankton nets, the Nansen net and the WP 2 net, were compared.The study was performed at six stations in the Baltic Sea andthe samples were collected during seasons of both high and lowparticle abundance. The comparison included both qualitativeand quantitative filtration capacity of the nets under differentenvironmental conditions. Different mesh sizes were also tested.The results show that the Nansen net has an efficiency of 5070%compared to the WP 2 net under favourable conditions. When conditionsare unfavourable, i.e. during periods of high particle abundanceor during long hauls, the efficiency may be as low as 2530%.The mesh size of the nets proved to be of decisive importancefor the qualitative composition of the samples. Most of thesmaller size fractions such as rotifers, copepod nauplii andyoung copepodites passed through the 160 and 200 µm meshes.The 90 µm nets sampled these fractions well but with thedrawback of retaining vast amounts of phytoplankton at certaintimes of the year. 相似文献
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Summary Bacterivory was detected by incorporation of 0.57 m diameter, fluorescent polystyrene beads and fluorescently labeled bacteria (FLB) in two cultured species of Cryptomonas (C. ovata and C. erosa), and a population of Cryptomonas sp in a humic, mesotrophic lake. Rates of ingestion and clearance were very low, and similar for the cultures and the in situ population. The in situ population incorporated 0.7–1.7 bacteria cell-1 h-1, thereby ingesting 0.3%–2.0% of the total bacterial numbers present in the water per day, and receiving less than 2% of its carbon content per day through bacterivory. Thus, bacterivory by Cryptomonas was quantitatively important neither as a sink for bacterial biomass, nor as a carbon source for the algal cells. Possibly, it served in the uptake of essential nutrients. 相似文献