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European Radiology - The strongest adverse prognostic factor in myxoid/round cell liposarcomas (MRC-LPS) is the presence of a round cell component above 5% within the tumor bulk. Its identification...  相似文献   
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BACKGROUND: Of patients who have undergone gastric banding, 11-25% will require a major reoperation with band removal and conversion to another bariatric procedure after they have failed to lose sufficient weight or have developed dysphagia or reflux. The aim of this study was to evaluate the respective benefits of Roux-en-Y gastric band (RYGB) or biliopancreatic diversion with duodenal switch (BPD-DS) after failed gastric banding and whether 1 of the 2 procedures might be a better procedure for such cases. METHODS: RYGB or BPD-DS was performed according to the institutional protocols with synchronous band removal, irrespective of the reason for failure. RESULTS: Of the 53 patients, 32 underwent laparoscopic RYGB for a body mass index (BMI) of 43.1 +/- 6.4 kg/m(2) (BMI 45.8 +/- 6.4 kg/m(2) before laparoscopic adjustable gastric banding) and 21 underwent BPD-DS for a BMI of 46.0 +/- 5.5 kg/m(2) (BMI 49.6 +/- 5.2 kg/m(2) before laparoscopic adjustable gastric banding). BPD-DS required significantly longer operative times (239.7 +/- 55.8 versus 135 +/- 26.7 minutes) and resulted in more complications (62% versus 12.5%; P <.002). No patients died postoperatively. The 2 groups of patients had a similar BMI at 12 and 18 months after revision (BMI 33.4 +/- 5.6 kg/m(2) and 31.4 +/- 3.5 kg/m(2)). The weight loss was greater after BPD-DS than after RYGB compared with the prerevision weight loss (66.2% versus 58.8% excess weight loss) or initial weight (73% versus 61.8%), although this was not significant. CONCLUSION: Despite an excessive rate of complications that were, in part, related to the learning curve in this series, BPD-DS resulted in greater weight loss compared with RYGB. However, both procedures were successful after failed gastric banding. A more accurate definition of failure could help to determine the respective indications for revisional surgery.  相似文献   
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Loading of tissue macrophages with dialysis-tubing-derived particles may occur during chronic haemodialysis. Previous studies have demonstrated that these particle-laden macrophages release significant quantities of prostaglandins. In these experiments, the effects of dialysis-tubing-particle loading on the release of the central inflammatory mediator, interleukin 1 (IL 1), was examined. Rats received daily injections of silicone or polyvinylchloride (PVC) particles, and were compared to animals given saline alone. The silicone and PVC groups received a total of 3 x 10(9) particles over a 4-week period. Non-stimulated peritoneal macrophages from control animals released a median of 4.1 (range 1.2-10.3) U IL 1 per 10(6) cells. In contrast, macrophages from silicone- and PVC-loaded animals spontaneously released high levels of IL 1 (median 21.8; range 10-36.7) and 94 (range 36-336) U per 10(6) cells respectively). Following in vitro stimulation with bacterial lipopolysaccharide (LPS), peritoneal macrophages from silicone- and PVC-treated animals released large amounts of IL 1 (median 538 (range 359-2017) U and median 653 (range 326-1134) U per 10(6) cells, respectively) as compared to LPS-stimulated macrophages from control animals (median 332 (range 130-306) U per 10(6) cells]. Zymosan or LPS stimulation of splenic cells from silicone- and PVC-loaded animals also secreted increased quantities of IL 1 as compared to controls. The chronic loading of tissue macrophages in dialysis patients with tubing-derived particles may result in augmented release of IL 1, with subsequent activation of inflammatory processes.  相似文献   
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PURPOSE: Recent studies suggest that donor B cells as well as T cells contribute to immune pathology in patients with chronic graft-versus-host disease (GVHD). B-cell activating factor (BAFF) promotes survival and differentiation of activated B cells. Thus, we tested whether BAFF correlated with chronic GVHD disease activity and time of onset after allogeneic hematopoietic stem cell transplantation (HSCT). EXPERIMENTAL DESIGN: Patients who had undergone allogeneic HSCT between 1994 and 2005 for hematologic malignancies were studied. ELISA was used to measure plasma BAFF levels and flow cytometry was used to assess BAFF receptor expression on B cells in patients with or without chronic GVHD. RESULTS: In 104 patients, BAFF levels were significantly higher in patients with active chronic GVHD compared with those without disease (P = 0.02 and 0.0004, respectively). Treatment with high-dose prednisone (>or=30 mg/d) was associated with reduced BAFF levels in patients with active chronic GVHD (P = 0.0005). Serial studies in 24 patients showed that BAFF levels were high in the first 3 months after HSCT but subsequently decreased in 13 patients who never developed chronic GVHD. In contrast, BAFF levels remained elevated in 11 patients who developed chronic GVHD. Six-month BAFF levels >or=10 ng/mL were strongly associated with subsequent development of chronic GVHD (P < 0.0001). Following transplant, plasma BAFF levels correlated inversely with BAFF receptor expression on B cells (P = 0.01), suggesting that soluble BAFF affected B cells through this receptor. CONCLUSION: These results suggest that elevated BAFF levels contribute to B-cell activation in patients with active chronic GVHD.  相似文献   
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Thank you for forwarding the letter of the distinguished colleagues,Andre Scheen and Luc Van Gaal, and the opportunity  相似文献   
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The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.  相似文献   
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