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PURPOSE: The extent of venous thromboembolism (VTE) associated with central vein catheters (CVC) in cancer patients remains unclear. The aim of this study was to evaluate the efficacy and safety of the low molecular weight heparin, enoxaparin, in the prevention of VTE. PATIENTS AND METHODS: In a multicenter, double-blind study, consecutive cancer patients scheduled for CVC insertion were randomly assigned to receive either subcutaneous enoxaparin 40 mg once a day or placebo. Treatment was started 2 hours before CVC insertion and continued for 6 weeks. The primary end points of the study were deep vein thrombosis (DVT), confirmed by venography of the CVC limb performed 6 weeks after randomization, or clinically overt pulmonary embolism, confirmed by objective testing during the study drug administration. Patients were assessed for bleeding complications. RESULTS: Three hundred eighty-five patients were randomized, of which 321 (83.4%) underwent venography. A venography was adequate for adjudication in 155 patients in each treatment group. A DVT was observed in 22 patients (14.1%) treated with enoxaparin and in 28 patients (18.0%) treated with placebo, corresponding to a relative risk of 0.78 (95% CI, 0.47 to 1.31). No major bleeding occurred. Five patients (2.6%) in the enoxaparin group and two patients (1.0%) in the placebo group died during the treatment period. CONCLUSION: In this study, no difference in the rate of CVC-related VTE was detected between patients receiving enoxaparin and patients receiving placebo. The dose of enoxaparin used in this study proved to be safe. Clinical trials evaluating higher enoxaparin doses could optimize the efficacy of this agent for this indication.  相似文献   
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PURPOSE: Although tumor resection is the mainstay of treatment for localized neuroblastoma, there are no established guidelines indicating which patients should be operated on immediately and which should undergo surgery after tumor reduction with chemotherapy. In an effort to develop such guidelines, the LNESG1 study defined surgical risk factors (SRFs) based on the imaging characteristics. PATIENTS AND METHODS: A total of 905 patients with suspected localized neuroblastoma were registered by 10 European countries between January 1995 and October 1999; 811 of 905 patients were eligible for this analysis. RESULTS: Information on SRFs was obtained for 719 of 811 patients; 367 without and 352 with SRFs. Of these 719 patients, 201 patients (four without and 197 with SRFs) underwent biopsy only. An attempt at tumor excision was made in 518 patients: 363 of 367 patients without and 155 of 352 patients with SRFs (98.9% v 44.0%). Complete excision was achieved in 271 of 363 patients without and in 72 of 155 patients with SRF (74.6% v 46.4%), near-complete excision was achieved in 81 and 61 patients (22.3% v 39.3%), and incomplete excision was achieved in 11 and 22 patients (3.0% v 14.2%), respectively. There were two surgery-related deaths. Nonfatal surgery-related complications occurred in 45 of 518 patients (8.7%) and were less frequent in patients without SRFs (5.0% v 17.4%). Associated surgical procedures were also less frequent in patients without SRFs (1.6% v 9.7%). CONCLUSION: The adoption of SRFs as predictors of adverse surgical outcome was validated because their presence was associated with lower complete resection rate and greater risk of surgery-related complications. Additional studies aiming to better define the surgical approach to localized neuroblastoma are warranted.  相似文献   
114.
BACKGROUND: Cigarette smoking influences and enhances the development of atherosclerosis. We investigated if nicotine, an important constituent of cigarette smoking, has a stimulatory effect on bovine smooth muscle cell proliferation in vitro through the mediation of bFGF and TGF-beta 1. METHODS: Bovine aortic smooth muscle cells (SMC) were stimulated with (-)-nicotine at various concentrations ranging from 6 x 10(-4) mol/L to 6 x 10(-8) mol/L. SMC viability and count were assessed. The presence of bFGF and TGF-beta 1 in serum-free conditioned media was determined by the inhibition antibody-binding assay, and the mitogenic activity of (-)-nicotine on SMC was analyzed by the 3H-thymidine uptake. Polymerase chain reaction was used to study the expression of bFGF and TGF-beta 1. RESULTS: The bFGF release after (-)-nicotine stimulation was greater than in the controls, whereas TGF-beta 1 release was lower. The greatest mitogenic activity was found at a (-)-nicotine concentration of 6 x 10(-6) mol/L. The addition of monoclonal antibody anti-bFGF decreased the 3H-thymidine uptake of SMC exposed to (-)-nicotine, whereas the addition of monoclonal antibody anti-TGF-beta 1 increased the 3H-thymidine uptake of stimulated SMC. bFGF mRNA expression was significantly higher in SMC exposed to (-)-nicotine than in the controls, but TGF-beta 1 mRNA expression was significantly lower in SMC exposed to 6 x 10(-6) mol/L (-)-nicotine than in SMC treated with the other concentrations of (-)-nicotine and in controls. CONCLUSIONS: Nicotine is a potent regulator of bFGF and TGF-beta 1 production and release by aortic SMC, and it seems to play an important role in the development and progression of atherosclerosis and neointimal fibrous hyperplasia.  相似文献   
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We describe the occurrence of small fiber neuropathy in a patient affected by Chagas disease in the indeterminate phase. After the exclusion of all the possible etiologies of small fiber neuropathy, the disorder was considered related to Trypanosoma cruzi infection. Although a peripheral involvement has been described in Chagas disease, this is the first report of a selective involvement of small fibers.  相似文献   
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Aim. To study any discriminative properties of SF-36 and QQL-EPM in stable and non-controlled moderate asthmatic patients. Methods. A total of 63 asthmatic patients were assessed regarding asthma symptoms, FEV1 % predicted value, PEF, ED visits and hospitalizations, QQL-EPM and SF-36 questionnaires. Results. QQL-EPM highlighted significance in all domains to distinguish stable from non-controlled patients (p = 0.0001) while SF-36 was only significant in 3 of its 7 domains (p = 0.009). Conclusion. The study showed that the specific quality of life questionnaire for asthma (QQL-EPM) demonstrates better discriminative properties that characterize asthma control when compared with the more generic SF-36 questionnaire.  相似文献   
120.
The objective of the present study was to test the association between Borderline Personality Disorder (BPD) and the cathecolamine-O-methyl-transferase (COMT) low-activity (Met158) single nucleotide polymorphism (SNP). In this case-control study, DNA was obtained from venous blood of 19 BPD patients and 36 healthy subjects. COMT-Val158Met single-nucleotide polymorphism was genotyped by predesigned SNP assay. The COMT Met158 allele was over-represented in patients with BPD in comparison to normal subjects (68.4% vs 44.4%, respectively; Fisher exact test, p = .02). In terms of genotype, the Met158Met subjects were more frequent in patients versus controls (47.4% vs 22.2%, respectively), whereas the high-activity genotype Val158Val was under-represented (10.5% vs 33.3%, respectively). The allele encoding for the COMT with low enzymatic efficiency was found to be over-represented in BPD, possibly resulting in excessive synaptic dopaminergic activity and ultimately affecting externalizing behaviours, such as impulsivity and aggressiveness.  相似文献   
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