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Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
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BACKGROUND: T lymphocytes play a crucial role in the pathogenesis of inflammatory bowel disease. Achieving stable T-cell lines, rather than continuous bleeding of patients, is desirable in order to dissect their implication in the disease. METHODS: Long-lasting T-cell lines from patients with Crohn disease and ulcerative colitis and from healthy volunteers have been obtained by transformation of T lymphocytes using the lymphotropic Herpesvirus saimiri. Lines were subjected to phenotypic and functional analyses, and the results compared with freshly isolated peripheral blood mononuclear cells. RESULTS: Fresh cells revealed only minor differences between patients and controls, with regard to phenotype and proliferative capacity. In contrast, the use of T-cell lines showed that cells from Crohn disease patients, but not ulcerative colitis patients, over-responded to several membrane or cytoplasmic stimuli when compared to control T-cell lines. Thus, higher responses were found when stimulated with alphaCD3 and IL2, alphaCD3 and alphaCD28, IL2 alone, phorbol esters (PMA) and alphaCD3 and, finally, PMA and alphaCD2 (P < 0.05 in all instances). Further, lines from patients with Crohn disease responded more vigorously to alphaCD3 and alphaCD28 or alphaCD3 and PMA when compared to ulcerative colitis (P < 0.05 in both instances). CONCLUSIONS: The data obtained with these lines suggest that T cells from patients with Crohn disease differ in vivo in their proliferative capacity, as compared with those from ulcerative colitis patients, a finding that may reflect the clear Th-1 phenotype found in the former and absent in the latter.  相似文献   
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Exogenous nucleotides (NT) have been reported to exert a reparative role in animal models of intestinal and hepatic damage. Thus, the administration of NT in the diet of rats with thioacetamide-induced liver cirrhosis normalized many of the histological and biochemical alterations produced by this hepatotoxin. We are currently studying the mechanism by which NT exert this effect using cell culture models. The aim of this work was to investigate whether exogenous nucleosides (NS) modulate the proliferation of hepatocytes. We used fetal rat hepatocytes, which, unlike adult hepatocytes, are proliferative cells. Fetal rat primary hepatocytes were incubated with mixtures of NS, and cell proliferation was studied. NS added to the medium of fetal hepatocytes were taken up in a selective fashion by the cells. Cell proliferation was enhanced, as demonstrated by the induction of c-myc and h-ras gene expression as well as by the higher percentage of cells in S phase, and exogenous NS increased the expression of alpha-fetoprotein. These results suggest that exogenous NS may in fact stimulate proliferation of hepatic cells and help preserve the undifferentiated state of fetal rat hepatocytes.  相似文献   
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Our objective was to assess the antitumoral activity and toxicity of irinotecan (CPT-11) 60-min i.v. infusion every 2 weeks as second-line monotherapy of advanced colorectal cancer. Two doses were studied (250 and 200 mg/m) according to the risk of developing toxicity. Two groups of patients were studied: high-risk group (HR, 200 mg/m, n = 45; Karnofsky score 60-80% and/or the record of prior pelvic irradiation) and low-risk-group (LR, 250 mg/m, n = 51; Karnofsky score >80% and without prior pelvic irradiation). The mean number of cycles per patient was 7: 6.6 (HR group) and 8.3 (LR group). Median RDI was 0.96. The overall response rate was 8.9% [95% confidence interval (CI) 2.5-21.2%; HR group] and 15.7% (95% CI 7.0-28.5%; LR group), respectively. The LR group showed two complete responses and a higher percentage of stable disease (56.9 versus 33.3% in HR group). The median survival was 7.1 months (95% CI 5.2-8.9 months, HR group) and 11.7 months (95% CI 8.4-15.1 months, LR group). The median time to disease progression was 3.2 months (95% CI 1.0-5.4 months, HR group) and 5.3 months (95% CI 3.8-6.7 months, LR group). Both CPT-11 treatments were well tolerated. Grade 3/4 toxicity incidence was low, e.g. granulocytopenia (7% of patients in HR group and 9% in LR group) and delayed diarrhea (18% of patients in HR group and 14% in LR group). We conclude that the treatment of patients with the adjusted dose of CPT-11 according to prognostic factors for toxicity resulted in the improved toxicity profile, but showed poorer efficacy outcome. Therefore, the dose reduction in patients with low performance and treated with radiotherapy needs further investigation to provide some new insights on the benefit:risk ratio of such treatment.  相似文献   
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