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51.
PURPOSE: To present a 7-year single-center clinical experience with fenestrated endografts and side branches. METHODS: Between April 1999 and August 2006, 63 patients (57 men; mean age 70.5+/-11.6 years, range 25-89) received custom-designed Zenith fenestrated endoprostheses for a variety of aneurysms (59 abdominal, 1 thoracoabdominal, and 3 thoracic). They were all unsuitable for standard EVAR owing to short aortic necks and high risk for open surgery. RESULTS: Nineteen tube grafts and 44 composite bifurcated grafts with a total of 122 fenestrations and 58 side branches were used. Technical success was achieved in 55 (87.3%) patients and in 118 (96.7%) vessels. Treatment success was 93.7%. The mean follow-up was 23+/-18 months (median 14, range 6-77). Overall, 9 (7.4%) visceral branches were lost: 4 intraoperative, 2 perioperative, and 3 late. There were 12 (19.0%) endoleaks identified: 5 (7.9%: 4 type Ia and 1 fenestration-related type III) primary and 7 (11.1%: 4 type II, 1 type I, and 2 type III) secondary endoleaks; 4 resolved, 4 were treated, and 4 are under observation. At 77 months, 75.3% of patients were free of a reintervention. All reinterventions were performed within the first 14 months. Fourteen cases of renal impairment were seen [6 permanent (only 1 on dialysis) and 8 transient]. One (1.6%) conversion and 1 (1.6%) rupture were recorded; aneurysm-related mortality was 4.8% (3/63). CONCLUSION: The favorable outcomes in this study, which encompasses the team's learning curve with fenestrated endografts and side branches, support the use of these devices in selected patients.  相似文献   
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Effects of melatonin on proliferation of cancer cell lines   总被引:1,自引:0,他引:1  
Papazisis KT, Kouretas D, Geromichalos GD, Sivridis E, Tsekreli OK, Dimitriadis KA, Kortsaris A.H. Effects of melatonin on proliferation of cancer cell lines. J. Pineal Res. 1998; 25:211–218. © Munksgaard, Copenhagen The pineal hormone melatonin has been reported to have in vitro antiproliferative effects on estrogen receptor-positive human breast cancer cell lines at concentrations near to plasma physiological concentrations (1 times 10-11 to 1 times 10-9 M). Its growth inhibitory actions have been thought to be linked to the estrogen-receptor system. We tested the cytotoxic effects of melatonin on MCF-7 and T47D human breast cancer cell lines by using the SRB (sulforhodamine-B), XTT-tetrazolium, and bromodeoxyuridine (BrdU) assays in 96-well microtiter plates. After a 3 or 4 day exposure, melatonin did not have any significant effect on breast cancer cell proliferation and survival in doses up to 1 times 10-4 M. Doses higher than 1 mM exhibited a potent cytotoxic effect, which was not mediated by the estrogen-receptor or by protein tyrosine kinases and was not specific for breast cancer cell lines. Intracellular glutathione levels did not seem to play any role in the sensitivity of breast cancer cells to melatonin, since the addition of L-buthionine-[S,R]-sulfoximine, ethacrynic acid, or exogenous glutathione did not modify our results. We conclude that under our experimental conditions melatonin has no inhibitory effects on human breast cancer cells at low (physiological or supraphysiological) concentrations. The different experimental procedures that were utilized in the present study can partially explain the divergence between our results and the literature.  相似文献   
53.
Liver blood flow measurements obtained from both the liver surface and deep within the parenchyma, were correlated in an effort to assess the usefulness of laser-Doppler flowmetry for non-invasive monitoring of total liver blood flow, the probe being positioned on either the surface or within the liver parenchyma.In 23 Wistar rats and 10 biliary surgery patients, anaesthetized prior to gallbladder removal, liver microcirculation was measured at 4 points on the capsular surface, and consequently at 4 points deep within the parenchyma, using probes connected to a laser-Doppler flowmeter. The findings revealed that laser-Doppler measurements on the liver surface and within the parenchyma were well correlated, as no statistically significant differences were found either in rats or humans. It is concluded that laser- Doppler flowmetry for monitoring of total liver perfusion can be applied either on the capsular surface or within the hepatic parenchyma.  相似文献   
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OBJECTIVES: In this study, we investigated whether polymorphisms of the HIF-1alpha gene may account for the patterns of HIF-1alpha protein expression in non-small cell lung carcinomas (NSCLC) and the expression of HIF-1alpha down-stream proteins. METHODS: Specific HIF-1alpha polymorphisms were assessed in a series of patients with NSCLC: (a) the C to T transition at nucleotide 1744 (position 2028 according to sequence with accession number , which gives rise to Pro/Ser variation at codon 582), (b) the G to A nucleotide substitution at point 1790 (position 2046 according to sequence with accession number , which gives rise to Ala/Thr variation at codon 588), and (c) the dinucleotide GT repeat polymorphism in intron 13. Immunohistochemistry for HIF-1alpha and down-stream proteins (VEGF, LDH-5, GLUT-1) was also performed in tumor material. RESULTS: A strong association of the P582S polymorphism and of GT repeat polymorphism higher than 14/14 with increased HIF-1alpha expression was noted. HIF-1alpha polymorphism did not relate to the expression of the HIF-1alpha downstream proteins analysed, but significant association of HIF-1alpha expression with LDH-5 was confirmed (p=0.008). CONCLUSIONS: HIF-1alpha polymorphisms may have an important impact on HIF-protein stability and, eventually, function.  相似文献   
56.
Angiogenesis is important for tumor growth and metastasis. This account reviews the clinicopathological studies conducted in the field of angiogenesis in colorectal cancer, the methods of assessing vascular-related characteristics in tissue sections and provides a background for the usefulness of antiangiogenic policies along with chemotherapy and radiotherapy. Highly angiogenic colorectal tumors are associated with aggressive histopathological features and poor patients' survival. Similarly, factors stimulating angiogenesis, such as vascular endothelial growth factor (VEGF), thymidine phosphorylase (TP), and others, are commonly related to increased vascular density (VD) and, therefore, to an unfavorable clinical course. Anti-VEGF agents have improved prognosis in patients with metastatic colorectal cancer, when added to standard chemotherapy. It is expected that, in addition to adjuvant chemotherapy and radiotherapy, agents blocking the stimulatory effect of VEGF on endothelial cells would prove beneficial to the patient.  相似文献   
57.
The number of positive lymph nodes (+LNs) is the only node-related prognostic factor recognized by the American Joint Committee TNM system for breast cancer. In this study, we evaluated additional node-related prognostic factors in node-positive breast carcinomas. One hundred and thirty-four patients with infiltrating ductal carcinomas and axillary +LNs, who had been treated with modified radical mastectomy, were analyzed. Metastatic lymph nodes were evaluated for traditional prognostic factors, i.e., the number of involved nodes and the extranodal extension, but also for a variety of other node-related characteristics, such as nodal tumor burden and maximum size of tumor deposits, necrosis, stromatogenesis, extranodal vascular involvement, and nodal matting. The results reaffirmed the prognostic significance of metastasis in 1-3 vs. 4-7 axillary lymph nodes and, in addition, revealed the importance of 4 +LNs as a cut-off point for breast tumor aggressiveness, given that survival curves for 4-7 vs. >7 +LNs were indifferent. Interestingly, nodal tumor burden, when extensive, was statistically an adverse prognostic factor. Prognosis was equally poor if metastases to regional nodes showed extensive nodal necrosis or extensive nodal stromatogenesis, if there was extranodal spread, extranodal vascular involvement, or if the axillary +LNs were matted. In multivariate analysis, intranodal necrosis and extranodal vascular involvement were the only node-related features with a significant and independent prognostic function. Node-related pathological features in node-positive breast carcinomas are important in determining prognosis. Intranodal necrosis and extranodal tumor emboli should be considered, in parallel with the number of +LNs, in subsequent treatment design.  相似文献   
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Background Since probiotics are considered to exert beneficial health effects by enhancing the host’s immune response, we investigated the benefits of a synbiotics treatment on the rate of infections, systemic inflammatory response syndrome (SIRS), severe sepsis, and mortality in critically ill, mechanically ventilated, multiple trauma patients. Length of stay in the intensive care unit (ICU) and number of days under mechanical ventilation were also evaluated. Method Sixty-five patients were randomized to receive once daily for 15 days a synbiotic formula (Synbiotic 2000Forte, Medipharm, Sweden) or maltodextrin as placebo. The synbiotic preparation consisted of a combination of four probiotics (1011 CFU each): Pediococcus pentosaceus 5–33:3, Leuconostoc mesenteroides 32–77:1, L. paracasei ssp. paracasei 19; and L. plantarum 2,362; and inulin, oat bran, pectin, and resistant starch as prebiotics. Infections, septic complications, mortality, days under ventilatory support, and days of stay in ICU were recorded. Results Synbiotic-treated patients exhibited a significantly reduced rate of infections (P = 0.01), SIRS, severe sepsis (P = 0.02), and mortality. Days of stay in the ICU (P = 0.01) and days under mechanical ventilation were also significantly reduced in relation to placebo (P = 0.001). Conclusion The administration of this synbiotic formula in critically ill, mechanically ventilated, multiple trauma patients seems to exert beneficial effects in respect to infection and sepsis rates and to improve the patient’s response, thus reducing the duration of ventilatory support and intensive care treatment.  相似文献   
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