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白细胞介素-13功能研究进展 总被引:5,自引:0,他引:5
白细胞介素-13主要由活化的Th2(CD4^ )细胞分泌,诱导单核巨噬细胞分化及延长寿命;促进MHC-Ⅱ,CD23表达;抑制炎性和趋化因子产生;诱导B细胞增殖,活化,刺激IgM,IgG的产生和重链的转换;使血管细胞粘附分子-1表达;抑制人类免疫缺陷病毒(HIV)复制;间接诱导巨噬细胞和NK细胞参与抗肿瘤作用。在变态反应性疾病和哮喘中引起呼吸道高反应性,嗜酸粒细胞性炎症,粘液分泌过多,基膜纤维化等,其受体是与IL-4Rα形成功能复合体而发挥作用。IL-13信号转导途径除了JAK/STAT6以外,尚有IRS-1,Fes,磷酸激酶,BCL-6/SOCS等途径。 相似文献
115.
N M Trugo C M Donangelo J C Koury M I Silva L A Freitas 《European journal of clinical nutrition》1988,42(6):497-507
The purpose of this study was to assess the concentration and binding pattern of zinc, iron, folate and vitamin B12 in milk of Brazilian women of low socioeconomic status giving birth at term or preterm, during early lactation. Protein, fat, total solids and ash concentrations were also determined. Protein and zinc concentrations decreased significantly as lactation proceeded whereas milk fat and folate increased with the lactation period. Total solids, ash, iron and vitamin B12 remained unchanged. Zinc was present mainly in the whey fraction while less than half of the total iron was present in this fraction, with no significant change due to stage of lactation. Unsaturated folate and vitamin B12 binding capacities and percentage of saturation of the folate binding protein increased with the stage of lactation. The vitamin B12 binding protein was highly unsaturated in all samples. There was no significant difference between term and preterm samples in the parameters investigated. Correlation analysis between milk components indicated significant relationships between total solids and fat, total zinc and whey zinc, folate and total folate binding capacity, unsaturated and total folate binding capacity, and unsaturated and total B12 binding capacity. In general, the nutrient concentrations found in this study are in good agreement with published data on milk composition of women from developed countries, with the possible exceptions of folate, which was lower, and iron, which was higher. The correlation of folate concentration with its binding protein found in this work supports the hypothesis of a regulatory role for folate levels in milk exerted by the folate binding protein in the mammary gland. 相似文献
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H J De Silva A K Goonetilleke N R De Silva L R Amarasekera U S Jayawickrama 《Postgraduate medical journal》1988,64(749):242-244
We report erythema induratum in a patient who was found to have active endometrial tuberculosis. This case report emphasizes the importance of an exhaustive search for active tuberculosis in patients with erythema induratum, especially in countries where tuberculosis is prevalent, as the indiscriminate treatment of erythema induratum with steroids may be harmful. 相似文献
119.
R Margis M Pinheiro-Margis L C da Silva R Borojevic 《International journal of experimental pathology》1992,73(2):125-135
We have studied the effect of retinol on an established murine cell line (GRX), representative of liver connective tissue cells. This cell line has myofibroblast characteristics; under retinol treatment it is induced into the lipocyte (Ito-cell) phenotype. Retinol decreased the proliferation rate in the entire cell population. It increased cell adherence to the substrate, which was correlated with the increased secretion of fibronectin. Collagen secretion was specifically decreased, whilst the total protein secretion remained stable. Heparan sulphate was decreased in the pericellular compartment, but other glycosaminoglycans were not affected by retinol treatment. Modulations of pericellular components induced by retinol may alter the relations among liver mesenchymal cells, and may be related to vitamin-A-induced modifications of the homoeostasis of hepatic connective tissue and hepatic fibrosis. 相似文献
120.
J M Guy M Lamaud A Da Costa L Bouvet A Cerisier H Verneyre 《Archives des maladies du coeur et des vaisseaux》1992,85(7):1047-1049
A 42 year old woman presented with a one year history of retrosternal chest pain and back pain on effort and at rest sometimes accompanied by minor syncopal attacks. Transient atrioventricular block was documented during one such episode associated with hypotension. Coronary angiography showed spontaneous spasm of the left main coronary artery with clinical symptoms but no electrocardiographic changes. The spasm was relieved by injection of SIN-1. The similarity between the previous clinical symptoms and those observed at coronary angiography was in favour of the diagnosis of spasm of the left main coronary artery without atherosclerotic coronary disease. Treatment with calcium atherosclerotic coronary disease. Treatment with calcium blockers and platelet antiaggregants led to total regression of her symptoms with a follow-up of 5 months. 相似文献