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81.
The principal criterion for resectability of pancreatic carcinoma is the assessment of vascular involvement. In a prospective evaluation the ability of Spiral CT Angiography (CTA) to detect vascular involvement in 50 patients with pancreatic carcinoma, was proved; DSA was performed later in all patients. In 20 patients, without vascular involvement, a complete concordance was obtained. Of 30 patients with vascular involvement, there was complete concordance between CTA and angiography in 22 patients and discordance in 8 patients. CTA was superior in 2 cases with periadventitial infiltration and in 5 patients with splenoportal confluence thrombosis. DSA was superior in 1 case with infiltration of the superior mesenteric vein. After surgical evaluation, sensitivity of CTA and DSA was 97% and 77%, respectively, and the negative predictive values were 95% and 74%. As compared to DSA, CTA is more rapid and less invasive and can be considered the modality of choice for preoperative work-up of pancreatic neoplasm.  相似文献   
82.
Dolichol (D) is a long-chain polyprenoid broadly distributed in the cell membranes, possibly endowed with a free-radical scavenging activity, whose concentration in tissues increases with increasing age. No enzyme pathway for D degradation has been discovered. In order to test the hypothesis that D might undergo a non-enzymatic free-radical mediated decomposition the effects of a xenobiotic agent (carbon tetrachloride, CCl(4)) and ultraviolet-B (UV-B) radiation on D levels were studied in liver cells isolated from male ad libitum fed Sprague-Dawley rats aged 3 or 24 months. Liver cells (90 mg/ml) were incubated in sealed flasks (6 ml cell suspension each) for 0, 5, 10 and 20 min after the addition of 25, 50 or 200 microl CCl(4) in the central well. 50 ml of a 6 mg/ml liver cell suspension were poured in a 120 cm(2) Petri dish and the sediment liver cell monolayer was exposed to UVB radiation for 0, 5, 10, 20 and 40 min. At the given time, cells were taken and D was extracted and assayed by the HPLC procedure. D levels were remarkably higher in older than in younger cells as expected ( P < 0.001). Treatment with CCl(4) and UVB caused a highly significant decrease in D ( P < 0.001) whose percentage was larger in younger than in older cells. The conclusions are that free-radicals generated either by chemical or by physical agents cause a very rapid depletion of D in liver cells, and that the effect of the free radical attack on D decomposition may be lower percentage wise in older than in younger cells, which might account at least in part for the accumulation of D in older tissues.  相似文献   
83.
84.
There are cases in which resection of cervico-mediastinal goitres requires additional thoracic access as an adjunct to standard transverse cervicotomy, and typically this takes the form of sternotomy or thoracotomy. The authors propose transclavicular access as an alternative to thoracotomy or sternotomy access for the removal of such goitres. This technical variant is performed by means of resection of the middle third of the clavicle and extraperiosteal disarticulation. They report a case of cervicomediastinal or "plunged" goitre associated with mediastinal metastasis from a follicular thyroid carcinoma in a 77-year-old woman, in whom this technical variant was used. They conclude by stressing the greater effectiveness, ease of execution and relatively limited "aggressiveness" of the technique in comparison with other ways of reaching the mediastinum. The variant proves effective in solving a number of technical, functional and aesthetic problems.  相似文献   
85.
86.
Endometrial carcinoma (EC) is the second most common tumor in hereditary nonpolyposis colorectal cancer (HNPCC), with an incidence rate of 60% by the age of 70 in mutation carriers. The International Collaborative Group on HNPCC revised the Amsterdam criteria and proposed a new, wider definition including extracolonic cancers. The aim of our study was to evaluate the accuracy of a new definition called Amsterdam criteria II. We updated, reclassified and compared the pedigrees of 29 women, already reported as being affected by EC and having a colorectal cancer familial background, according to the two clinical diagnostic criteria for HNPCC (Amsterdam criteria I, ACI, and Amsterdam criteria II, ACII) after two periods of observation (1990-1995 and 1995-2000). According to ACII the frequency of HNPCC in the population under study increased from 0.9% to 3.7% in the period 1990-1995 and from 3.2% to 3.7% in the period 1995-2000. ACII allowed early detection of HNPCC families and thus made it possible to provide them with a suitable surveillance program and genetic testing.  相似文献   
87.
Seventeen patients affected by acute myeloid leukemia (AML) with t(8;21) were prospectively programmed to receive three courses of high-dose cytarabine (HDARA-C) as post-remission therapy. The median age was 39 years and in all cases t(8;21) was the only karyotypic abnormality. Complete remission (CR) was achieved in 14 out of 17 cases (82%) and, after first consolidation with NOVIA regimen (intermediate dose ARA-C plus mitoxantrone), all patients received the three planned courses of HDARA-C (3g/m(2) q12h on days 1, 3, 5). There were two documented infections, while all patients experienced fever of unknown origin (FUO). Nonhematological toxicity was mild. Thirteen out of 14 patients are in continuous CR after a median follow-up of 44 months. One patient relapsed at 16 months and, following CR2 achievement, underwent allogeneic transplantation; he died 3 months later while in CR from acute graft versus host disease (GVHD). Survival at 5 years is projected at 79%. Our data confirm the efficacy of repeated courses of HDARAC for patients with t(8;21) AML.  相似文献   
88.
Antibodies to heparan sulfate (HS) have previously been found in association with peripheral neuropathy. We tested sera from patients with neuropathies and with other neurological diseases for antibodies to HS using an avidin-biotin enzyme-linked immunosorbent assay (ELISA) system. Increased titers of anti-HS antibodies were found in 3.4% of patients with neuropathy, and in 3% of patients with other neurological diseases. In all cases, however, an inflammatory disease was present, including chronic inflammatory neuropathy, cerebral vasculitis, or multiple sclerosis. Antibodies to HS appear not to be specific for neuropathy, as they occur in several inflammatory diseases. They might contribute to the associated breakdown of the blood-brain or blood-nerve barrier.  相似文献   
89.
A large proportion of patients have both hypertension and hypercholesterolemia, two of the most important risk factors for cardiovascular diseases. Statins are the most widely used drugs for the treatment of plasma lipid abnormalities and have been reported to interact with elevated blood pressure. A reduction in blood pressure associated with the use of these agents has been reported in patients with untreated hypertension and in patients treated with antihypertensive drugs, particularly angiotensin-converting enzyme inhibitors and calcium channel blockers. This effect on blood pressure control has also been observed in diabetic patients. The mechanism responsible for the hypotensive effect seems to be largely independent of the effect of statins on plasma cholesterol, and probably is related to the interaction of the medications with endothelial function or angiotensin II receptors. The capacity of statins to improve blood pressure control may represent a useful tool for improvement in the prevention of cardiovascular diseases.  相似文献   
90.
PURPOSE: To assess the value of changes in the expression of topoisomerase IIalpha (TopoII) and the proto-oncogene erbB-2 (HER-2) as predictors of relapse-free survival in women with operable breast cancer treated with anthracycline-based neoadjuvant chemotherapy. PATIENTS AND METHODS: Seventy-seven patients with primary breast cancer who had undergone neoadjuvant anthracycline-based chemotherapy were included in the present study. TopoII and HER-2 were measured by immunohistochemistry in prechemotherapy and postchemotherapy (at the time of surgery) tumor specimens, and the value of their changes as predictors of relapse-free survival were evaluated by Kaplan-Meier and Cox proportional hazard regression analyses. RESULTS: Neoadjuvant chemotherapy resulted in a significant reduction in the percentage of cells expressing TopoII (P < 0.0001). No significant change was observed for HER-2. TopoII and HER-2 expression before chemotherapy predicted tumor response to treatment. Changes in TopoII expression after chemotherapy were strongly associated with a poor relapse-free survival (P < 0.0001) in a Cox multivariate analysis adjusted for other clinicopathologic prognostic factors. CONCLUSION: Changes in TopoII expression after anthracycline-based neoadjuvant chemotherapy is an independent predictor of a poor relapse-free survival in patients with breast cancer. Tumor cells displaying an increased TopoII expression after treatment may be responsible for relapses, and may, therefore, define a group of patients with anthracycline-resistant breast cancer.  相似文献   
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