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AIMS: To investigate the contribution of regulatory T cells and co-stimulatory molecules in CD4(+) T cells to the development of Type 1 diabetes (T1D). METHODS: Twelve patients with T1D, nine patients with systemic lupus erythematosus (SLE), and 12 age-matched healthy control subjects participated. We analysed the proportions of CD25(+)CD4(+) T cells and natural killer T cells (NKT cells), and the expression levels of Foxp3, CTLA-4, CD28, ICOS, PD-1 and BTLA in peripheral blood mononuclear cells and purified CD4(+) T cells. RESULTS: There were no significant differences in the proportions of CD25(+) CD4(+) T cells or NKT cells among the three groups. PD-1 expression levels of peripheral CD4(+) T cells from T1D patients were significantly lower than those from healthy control subjects (P = 0.00066). In contrast, PD-1 expression levels were similar in SLE patients and healthy control subjects. The expression levels of Foxp3, CTLA-4, CD28, ICOS and BTLA were similar in the three groups. CONCLUSIONS: Decreased expression of the PD-1 gene in CD4(+) T cells may contribute to the development and/or maintenance of autoimmune T1D. As the population studied was small and heterogeneous, further studies are required to confirm the findings.  相似文献   
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Thirty-five patients with T2–T4 invasive bladder cancer were treated with combined cisplatin and radiation therapy. In 18 patients radical cystectomy was performed after the combined therapy. In the other 17 patients radical cystectomy could not be performed for various reasons. Pathological examination of the cystectomy specimens showed down-staging in 66.7% and no residual tumour in 33.3%. These results suggest a synergistic action of cisplatin and radiation. Side effects were not severe and were well tolerated. This combined therapy of cisplatin and radiation is very effective for invasive bladder cancer.  相似文献   
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目的探讨碱性成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)对晶体上皮细胞促增殖作用的机理。方法从培养的第二代牛眼晶体上皮细胞提取RNA,经逆转录反应合成cDNA。借助从人体胎盘纤维细胞bFGF受体序列合成的寡核苷酸引物,聚合酶链反应体外扩增cDNA。扩增的cDNA片段克隆后,Sanger双脱氧链终止法测定其序列。结果探测出牛眼晶体上皮细胞bFGF受体的mRNA,测序后发现其氨基酸序列片段中仅3个氨基酸与人体不同。结论晶体上皮细胞存在bFGF受体,当bFGF与其受体结合后,对促进晶体上皮细胞的增殖以及白内障术后后囊混浊具有重要作用。  相似文献   
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The lenses of ICR/f-strain rats with hereditary cataract were monitored in situ by laser Raman spectroscopy. The lenses used were within the age of 3-10 weeks before lens opacification became manifest. The reduction of protein SH group content and the increase of protein S-S bond content were observed in ICR/f rats in the precataractous stage. No significant change in the water content was observed.  相似文献   
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Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1). Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases. Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis, immunoexpression of differentiation markers was examined. Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every NF1 case.  相似文献   
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Background: Tacrolimus (FK506) is currently used as the primary immunosuppressant in clinical kidney transplantation in some centers. The purpose of this study was to evaluate the pharmacokinetics of this drug and to see if trough level, which has been used widely in therapeutic drug monitoring, can be used as an appropriate substitute for other pharmacokinetic measurement tests. Methods: The blood concentration-time curve was studied in 10 kidney transplant recipients on 26 Occasions after oral dosage of 2 to 18 mg every 12 hours. Whole blood concentration was measured by two-step irnmunoabsorption assay. Methylprednisolone was used as a concomitant immuno-suppressive drug. Results: The blood concentration-time curves showed remarkable interindividual variation. lntraindividual variation was also found, but the degree of variation was slight compared with interindividual variation. On 17 occasions of measurement in one patient, the dose was significantly correlated with trough (r = 0.684). Cmax (r = 0.838) and AUC0–12 (r = 0.817). In nine patients on nine occasions, however, the dose was not significantly correlated with trough (r = 0.351), Cmax (r = 0.270) or AUC0–12 (r = 0.355). tmax ranged from one to four hours (mean + SD; 2.8 + 1.3) and fluctuated in both intra- and interindividual measurements. In spite of a wide variation in the blood concentration-time-curve patterns, a highly significant linear relationship between trough and Cmax or AUC0–12 was observed in both intraindividual (Cmax, r = 0.876; AUC0–12, r = 0.926) and interindividual (Cmax, f = 0.943; AUC0–12, r = 984) measurements. Concluslons: We conclude that trough level is a practical acceptable indicator of the blood levels of tacrolimus, and can be used to monitor blood concentration.  相似文献   
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Wu  K; Urano  T; Ihara  H; Takada  Y; Fujie  M; Shikimori  M; Hashimoto  K; Takada  A 《Blood》1995,86(3):1056-1061
The effect of the proteolytic cleavage of plasminogen activator inhibitor type 1 (PAI-1) by human neutrophil elastase (HNE) on fibrinolysis was investigated. HNE cleaved active PAI-1 and produced low molecular weight forms of inactive PAI-1, as previously reported. Latent PAI-1 was resistant to HNE treatment. Vitronectin (VN) partially protected the cleavage. NH2-terminal sequence analysis indicated that the cleavage site was Val355-Ser356 (P4-P3). The effects of PAI-1 cleavage by HNE on clot lysis was studied in a purified system. Clot lysis time without PAI-1 was 20.0 +/- 5.0 minutes and was prolonged to 86.7 +/- 2.9 minutes by 68 nmol/L of PAI-1. It was shortened when HNE (from 0.6 nmol/L to 80 nmol/L) was added and returned to the value obtained without PAI-1 by 80 nmol/L of HNE (20.0 +/- 5.8 minutes). However, in the absence of PAI-1, elastase did not enhance clot lysis at all. Euglobulin clot lysis time was also shortened after HNE treatment. The cleavage and inactivation of PAI-1 by HNE was shown to be a novel pathway to enhance fibrinolysis.  相似文献   
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