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Plasma cell populations in labial salivary glands from patients with and without Sjögren's syndrome 总被引:1,自引:0,他引:1
Plasma cells expressing IgG, IgA and IgM were quantified in labial salivary glands from patients with Sjögren's syndrome (n = 25) and compared with glands from patients with a variety of systemic diseases (n = 32) and normal individuals (n = 15). Based on qualitative and quantitative analysis, glands from the systemic disease group were divided into normal histology (n = 24) and non-specific inflammation (n = 8) groups. There were no significant differences in cell densities or Ig class proportions between histologically normal glands from patients and those from normal volunteers. Total immunocyte densities were significantly increased in sialadenitis ( P ≤0.025) and Sjögren's syndrome ( P ≤0.001) compared with normal histology glands. In both the sialadenitis and Sjögren's syndrome groups there were significant increases in IgG and IgM cell densities (IgG, P ≤0.006; IgM, P ≤0.001) and proportions (IgG, P ≤0.05; IgM, P ≤0.001). There were no significant differences in immunocyte densities or proportions between the sialadenitis and Sjögren's syndrome groups except for a lower percentage proportion of IgA cells in the latter ( P ≤0.038). In all groups the total and individual Ig-class cell densities showed significant positive correlations with extent of leucocyte infiltration ( P ≤0.01) and negative correlations between IgA and IgG and/or IgM cell proportions. Analysis of the plasma cell data alone and in combination with quantifiable histological parameters failed to yield specific or sensitive diagnostic information. The results suggest that changes in glandular plasma cell populations in Sjögren's syndrome are non-specific. 相似文献
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B. GRIFFITHS D. J. MATTHEWS L. WEST J. ATTWOOD S. POVEY D. M. SWALLOW J. R. GUM Y. S. KIM 《Annals of human genetics》1990,54(4):277-285
A cDNA coding for a mucin expressed in intestine has recently been cloned (Gum et al. 1989). We describe here the use of this cDNA to map the gene (MUC2) to human chromosome 11 using somatic cell hybrids, and to make the regional localization to 11p15 by in situ hybridization. Analysis of the CEPH (Centre 'Étude du Polymorphisme Humain) families revealed that MUC2 forms part of the tight linkage group on llpl5 which contains HRAS, INS, TH and HBBC. 相似文献
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Management of small‐bowel fistulas which are in an open abdomen and have no soft tissue overlay or a fistula tract involves many complications and challenges. Controlling the local leakage of enteric contents has a central role in the success of medical treatment. There are several methods to deal with fistula discharge but unfortunately, the technical solutions only partially address such problems and a definitive management of fistula discharge still remains an insoluble challenge. We describe a simple and cheap method to control fistula leakage by using a percutaneous endoscopic gastrostomy tube. 相似文献
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OBJECTIVE: To prospectively document the prevalence of otitis media with effusion (OME) in 86 African-American children between ages 2 and 5 years. STUDY DESIGN: Eighty-six children in center-based child care whose ear status had been followed from infancy continued to be observed. Middle ear status was assessed by pneumatic otoscopy and tympanometry biweekly. RESULTS: The prevalence of OME decreased as children became older. The mean proportion of examinations demonstrating bilateral OME (BOME) ranged from 12% between 24 to 30 months to 4% between 54 to 60 months of age. The mean proportion of exams revealing bilateral normal ears increased from 77% at 24 to 30 months to 88% at 54 to 60 months of age. Although 60 children had experienced BOME that lasted 4 months or longer in the 6- to 24-month age period, only 8 of these children experienced at least 4 months of continuous BOME between 24 to 60 months. CONCLUSIONS: The proportion of time with BOME decreased progressively with increasing age in this population. Only 8 of 60 children who had experienced more than 4 consecutive months of BOME before 2 years of age continued to manifest persistent effusion or experience recurrences of prolonged BOME after 2 years of age. 相似文献
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血小板冷藏会使血管假性血友病因子受体复合物(von Willebrand factor receptor complex)聚集成簇。巨噬细胞αMβ2 整合素结合在成簇复合物的GPIbα亚基,导致输注的冷藏血小板被快速清除。因此输注用血小板不能冷藏,但现在的室温保存方式也存在很大缺点。我们已证明αMβ2是一种凝集素,它能识别GPIbα的N-连接葡聚糖上暴露的β-N-乙酰葡萄胺。冷藏血小板的酶促半乳糖苷化阻止了αMβ2的这种识别,延长了有 相似文献