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BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
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The eruption pattern of permanent teeth in miniture swine   总被引:1,自引:0,他引:1  
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Multispectral analysis of magnetic resonance images   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.  相似文献   
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PURPOSE: The initial determinants of retinal microvascular damage in diabetic retinopathy are not well understood, but are likely to be induced by hyperglycemia and/or dyslipidemia. The purpose of this study was to examine the effect of fatty acids and hyperglycemia on human retinal vascular endothelial (hRVE) cells as a means of mimicking diabetic metabolic disorders. METHODS: The expression of adhesion molecules in hRVE and human umbilical vein endothelial cells (HUVECs) was assayed by Western blot analysis and confirmed by leukocyte adhesion assay. The mechanisms underlying the induction of adhesion molecules by fatty acids were further investigated by using cyclooxygenase (COX), lipoxygenase (LOX), and P450 monooxygenase (MOX) inhibitors. RESULTS: Treatment of hRVE cells with the n6 polyunsaturated fatty acids (PUFAs) 18:2n6 and 20:4n6 for up to 24 hours resulted in a significant induction of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 protein levels. In contrast, treatment with high glucose (22 mM) for 24 hours did not affect CAM expression. Induction of CAM by n6 PUFA correlated with enhanced leukocyte binding to hRVE cells. The effect of n6 PUFA on ICAM-1 and VCAM-1 was blocked by an inhibitor of LOX, but not by COX or MOX inhibitors. In contrast to hRVE cells, n6 PUFA did not induce ICAM-1 or VCAM-1 in HUVECs. CONCLUSIONS: The data obtained in this study demonstrate that acute exposure to linoleic or arachidonic acid, but not hyperglycemia, induces inflammatory adhesion molecule expression in the presence of LOX in microvascular hRVE cells, but not in HUVECs. These results are consistent with the emerging hypothesis recognizing early-stage diabetic retinopathy as a low-grade chronic inflammatory disease.  相似文献   
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