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排序方式: 共有139条查询结果,搜索用时 15 毫秒
1.
Neuronal activation was examined by fos immunohistochemistry in ring doves (Streptopelia risoria) reunited with their young after overnight separation. In an initial study, squab-exposed parents showed more fos immunoreactivity (ir) in the preoptic area (POA) and lateral hypothalamus (LH) than squab-deprived parents. In a 2nd study, parents allowed free access to young and those separated from young by a wire mesh partition showed more fos-ir in the POA, LH, and lateral septum than box-exposed controls. Contact with young also increased fos-ir in the medial preoptic nucleus and bed nucleus of the stria terminalis, but noncontact exposure did not. Conversely, nontactile squab exposure stimulated more fos-ir in the POA than did free access to young, which suggests POA involvement in appetitive aspects of parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
A semi‐automated imaging system is described to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer. The system works for any conventional method of image acquisition using microscopic slides that have been processed for immunohistochemical analysis of the estrogen receptor and progesterone receptor. Estrogen receptor and progesterone receptor immunohistochemical staining produce colorimetric differences in nuclear staining that conventionally have been interpreted manually by pathologists and expressed as percentage of positive tumoral nuclei. The estrogen receptor and progesterone receptor status of human breast cancer represent important prognostic and predictive markers of human breast cancer that dictate therapeutic decisions but their subjective interpretation result in interobserver, intraobserver and fatigue variability. Subjective measurements are traditionally limited to a determination of percentage of tumoral nuclei that show positive immunoreactivity. To address these limitations, imaging algorithms utilizing both colorimetric (RGB) as well as intensity (gray scale) determinations were used to analyze pixels of the acquired image. Image acquisition utilized either scanner or microscope with attached digital or analogue camera capable of producing images with a resolution of 20 pixels /10 μ. Areas of each image were screened and the area of interest richest in tumour cells manually selected for image processing. Images were processed initially by JPG conversion of SVS scanned virtual slides or direct JPG photomicrograph capture. Following image acquisition, images were screened for quality, enhanced and processed. The algorithm‐based values for estrogen receptor and progesterone receptor percentage nuclear positivity both strongly correlated with the subjective measurements (intraclass correlation: 0.77; 95% confidence interval: 0.59, 0.95) yet exhibited no interobserver, intraobserver or fatigue variability. In addition the algorithms provided measurements of nuclear estrogen receptor and progesterone receptor staining intensity (mean, mode and median staining intensity of positive staining nuclei), parameters that subjective review could not assess. Other semi‐automated image analysis systems have been used to measure estrogen receptor and progesterone receptor immunoreactivity but these either have required proprietary hardware or have been based on luminosity differences alone. By contrast our algorithms were independent of proprietary hardware and were based on not just luminosity and colour but also many other imaging features including epithelial pattern recognition and nuclear morphology. These features provide a more accurate, versatile and robust imaging analysis platform that can be fully automated in the near future. Because of all these properties, our semi‐automated imaging system ‘adds value’ as a means of measuring these important nuclear biomarkers of human breast cancer.  相似文献   
3.
Removing peanut allergens by tannic acid   总被引:1,自引:0,他引:1  
Tannic acid (TA) forms insoluble complexes with proteins. The aims here were to remove major peanut allergens as insoluble TA complexes and determine if they would dissociate and release the allergens at pH 2 and 8 (gut pH). Release of the allergens in the gut could lead to absorption and consequently an allergic reaction. TA (0.25, 0.5, 1, and 2 mg/ml) was added to a peanut butter extract (5 mg/ml; pH 7.2), stirred, and centrifuged. The precipitates were then suspended in buffer at pH 2, centrifuged, re-suspended at pH 8, and centrifuged. Supernatants from each step were analysed by SDS–PAGE, ELISA, and Western blots. The effect of NaCl (1 M) on complexes was also determined. Results showed that complexes formed at a TA concentration >0.5 mg/ml did not release major peanut allergens at pH 2 and 8, regardless of 1 M NaCl being present or not. IgE binding of the extracts was reduced substantially, especially at a TA concentration of 1–2 mg/ml. Animal or clinical studies are still needed before TA can find an application in the development of low-allergen peanut products/beverages or the removal of peanut allergens due to accidental ingestion.  相似文献   
4.
Mast cells are tissue-resident immune cells that function in both innate and adaptive immunity through the release of both preformed granule-stored mediators, and newly generated proinflammatory mediators that contribute to the generation of both the early and late phases of the allergic inflammatory response. Although mast cells can be activated by a vast array of mediators to contribute to homeostasis and pathophysiology in diverse settings and contexts, in this review, we will focus on the canonical setting of IgE-mediated activation and allergic inflammation. IgE-dependent activation of mast cells occurs through the high affinity IgE receptor, FcεRI, which is a multimeric receptor complex that, once crosslinked by antigen, triggers a cascade of signaling to generate a robust response in mast cells. Here, we discuss FcεRI structure and function, and describe established and emerging roles of the β subunit of FcεRI (FcεRIβ) in regulating mast cell function and FcεRI trafficking and signaling. We discuss current approaches to target IgE and FcεRI signaling and emerging approaches that could target FcεRIβ specifically. We examine how alternative splicing of FcεRIβ alters protein function and how manipulation of splicing could be employed as a therapeutic approach. Targeting FcεRI directly and/or IgE binding to FcεRI are promising approaches to therapeutics for allergic inflammation. The characteristic role of FcεRIβ in both trafficking and signaling of the FcεRI receptor complex, the specificity to IgE-mediated activation pathways, and the preferential expression in mast cells and basophils, makes FcεRIβ an excellent, but challenging, candidate for therapeutic strategies in allergy and asthma, if targeting can be realized.  相似文献   
5.
目的探索牛奶主要过敏原的制备工艺。方法采用等电点沉淀、凝胶层析和分子筛等技术纯化牛奶中主要过敏原组分;采用SDS-PAGE鉴定蛋白纯度,采用双抗原夹心-ELISA鉴定免疫活性。结果成功获得牛奶中的四种主要过敏原组分:酪蛋白、β乳球蛋白、α乳白蛋白和分子量较高的P1组分,并经过免疫实验证实这四种组分均能与过敏血清产生反应,而其中β乳球蛋白和P1组分反应性较高。结论本研究探索出一种简单、实用的牛奶主要过敏原制备工艺,并证实牛奶中的β乳球蛋白和高分子量蛋白质为主要过敏原。  相似文献   
6.
7.
BACKGROUND: Tea (Camellia sinensis L.) is consumed all over the world and in especially large quantities in Japan and China, where it has been used not only as a daily beverage but also for medicinal purposes for thousands of years. Tea has been found to exhibit various bioregulatory activities, including antiallergic, anticarcinogenic, antimetastatic, antioxidative, antihypertensive, antihypercholesterolemic, anti‐dental caries and antibacterial effects, and to influence intestinal flora. RESULTS: Cha Chuukanbohon Nou 6 is a tea cultivar improved by the National Institute of Vegetable and Tea Science (NIVTS) in Japan. On comparing chemical constituents of 11 varieties of tea leaves by high‐performance liquid chromatography, we found two new major compounds in Cha Chuukanbohon Nou 6. Nuclear magnetic resonance spectroscopy revealed these compounds to be theogallin and 1,2‐di‐O‐galloyl‐4,6‐O‐(S)‐hexahydroxydiphenoyl‐β‐D ‐glucopyranose. The two were similar in chemical structure to strictinin, an inhibitor of immunoglobulin (Ig) production. Thus their effects on the production of Igs by peripheral blood lymphocytes were tested. Both compounds, like strictinin, inhibited IgE production. CONCLUSION: The results suggest Cha Chuukanbohon Nou 6 to be the basis of an antiallergic beverage. Copyright © 2009 Society of Chemical Industry  相似文献   
8.
The effect of hydroperoxide in breads on antigen-antibody reaction against IgE was examined. We compared the antigen-antibody reaction against IgE between dough including hydroperoxide and that not including hydroperoxide. Crude proteins extracted from the dough including hydroperoxide showed weak antigen-antibody reaction on allergic tests such as ring precipitin test with human-specific IgE, and the IgE binding activity on ELISA. In contrast, the dough without hydroperoxide showed antigen-antibody reaction. The crude proteins extracted from the dough with hydroperoxide or without hydroperoxide were applied by affinity chromatography of trypsin-immobilized chitin. Then proteins having affinity were recovered. The recovered proteins were separated by SDS-PAGE. Each protein was examined for the IgE binding activity on ELISA. The IgE binding activity of baked bread was studied as well. Crude proteins of baked bread made from dough including hydroperoxide showed weaker IgE binding activity on ELISA than proteins of baked bread made from dough without hydroperoxide. Those results suggested that addition of hydroperoxide into dough affects on antigen activation.  相似文献   
9.
食品过敏原检测与评价技术研究进展   总被引:14,自引:2,他引:14  
黄峙  郭宝江 《食品科学》2003,24(8):240-244
过敏原生物活性包括过敏原性即引起致敏个体发生过敏症的活性和致敏原性即引起人群致敏的危险性两个方面。随着转基因作物及相应食品的大量出现,评价和检测食品过敏原生物活性日益受到重视。迄今,食品过敏原性的主要检测方法有:皮肤试验、双盲安慰剂对照激发试验、血清IgE检测和组胺释放试验等;对食品致敏原性还没有建立可靠的评价和监测技术,FAO/WHO采纳的分级评价策略包括血清学测定、过敏原分子结构和序列同源性比较及胃肠液消化稳定性评价等。本文对食品过敏原生物学活性的评价与检测技术研究进展进行综述。  相似文献   
10.
We found that two distinct flavonoid glycosides isolated from the peel of Japanese persimmon (Diospyros kaki Fuyu), isoquercitrin (Isq) and hyperin (Hyp), are capable of inhibiting antigen-stimulated degranulation in rat basophilic leukaemia RBL-2H3 cells. In order to elucidate the underlying mechanisms, we examined effects of Isq and Hyp on cellular responses induced by antigen stimulation. Treatment with both Isq and Hyp markedly inhibited antigen-stimulated elevation of intracellular free Ca2+ concentration and reactive oxygen species (ROS). Isq and Hyp did not affect NADPH oxidase (NOX) activity, but they possessed DPPH radical-scavenging activity similar to that of epigallocatechin gallate, a potent anti-oxidant, Finally, Isq and Hyp showed little or no effects on Ag-stimulated Syk activation or phosphorylation of signalling molecules. These results indicate that inhibition of antigen-stimulated degranulation by Isq and Hyp is mainly due to suppression of intracellular Ca2+ elevation, which is caused by direct scavenging of ROS that are generated by NOX. Our findings suggest that Isq and Hyp, isolated from the peel of persimmon, would be beneficial for alleviating symptoms of type I allergy.  相似文献   
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