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As editors we want as many people to have access to NDT as possible.The last 18 months have seen a number of experimental initiativesto test the technical and logistical  相似文献   
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We have delineated regions of interest at chromosome 2q21.2, 2q36.3, and 2q37.1 by deletion mapping of 114 urothelial cancers (UC). Altogether, 17%, 18%, and 63% of the G1, G2, and G3 tumors displayed loss of heterozygosity at chromosome 2q, respectively, The region at 2q21.2 was narrowed down to the LRP1B gene (NT_005129.6). Hemi- and homozygous deletion at the LRP1B gene region was seen in 31 of 114 UCs. Only 8% of the UCs with G1 and none with G2 tumors showed loss of heterozygosity at the LRP1B gene, whereas 49% of the G3 UCs had allelic loss at this region. RT-PCR analysis of the LRP1B gene showed the lack of expression of several exons in 2 of 9 cases analyzed. Our analysis suggests that the LRP1B gene is a candidate tumor suppressor gene in UCs.  相似文献   
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The recent history of French and Brazilian medicine goes back to the first decades of the xixth century. As regards nephrology, the first links were established starting in the 1950s of the xxth century. Over the past 60 years, the scientific production of the Franco-Brazilian school of nephrology totalized more than a thousand scientific papers and created a new generation of more than two hundred disciples, formed in Brazil by nephrologists who had completed their studies in France. In this article, we would like to memorize the successive exchanges between French and Brazilian physicians, mainly in the field of nephrology.  相似文献   
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BACKGROUND: In a recent uncontrolled retrospective report we suggested that the long-term supplementation of high-dose, i.v. folinic acid combined with high-dose i.v. pyridoxine was highly effective in correcting plasma total homocysteine (tHcy) concentrations in haemodialysis patients. To confirm these findings, we conducted a randomized, controlled trial aimed at evaluating whether i.v. or oral folinic acid provided improved tHcy-lowering efficacy in haemodialysis patients compared with oral folic acid. METHODS: In a 6-month prospective, randomized, controlled trial, 60 chronic haemodialysis patients, matched for age, gender, dialysis duration, and average screening pre-treatment-fasting tHcy levels, were given either 50 mg/week of i.v. calcium folinate (group 1), 50 mg/week of oral calcium folinate (group 2), or 45 mg/week oral folic acid (group 3). All 60 patients also received 750 mg/week of i.v. vitamin B6 and 3 mg/week of oral vitamin B12. RESULTS: Fasting tHcy decreased significantly and to a similar extent in the three groups after 2 months of treatment and remained stable at 4 and 6 months (16.6+/-3.5, 18.3+/-4, and 19.1+/-3.1, in groups 1, 2, and 3, respectively, P=NS). Mean percentage reduction at 6 months was also similar in the three treatment groups (46, 43, and 42% in groups 1, 2, and 3, respectively, P=NS). CONCLUSIONS: These findings show that the tHcy-lowering effects of high-dose i.v. folinic acid, oral folinic acid, or oral folic acid were comparable, suggesting that the hyperhomocysteinaemia observed in haemodialysis patients is not due to abnormal folate metabolism. Furthermore, they are compatible with the view that other abnormalities are also involved in the impaired clearance of homocysteine in uraemic patients.  相似文献   
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A gold standard for the correct rotation of the tibial component has not been established in total knee arthroplasty (TKA). The target parameter of correct rotation is the facilitation of femorotibial rotation over the entire range of motion with no implant overhang. Although the origin of the lateral collateral ligament is a recognized landmark for determining the rotation of the femoral component (epicondylar axis), the attachment of the lateral collateral ligament has not been taken into consideration for adjusting tibial rotation until now. The objective of the current investigation was to examine whether the position of the fibular head, as the attachment of the lateral collateral ligament, influences femorotibial rotation. Seventy patients who underwent TKA were enrolled in this retrospective study. Computed tomography (CT) of the operated knee was performed 6 months postoperatively in all cases and the position of the lateral facet of the fibular head and the tibial tuberosity, and the geometric center of the tibia and the femoral epicondyles were determined. The angle between the lateral facet of the fibular head, the geometric center of the tibia, and the tibial tuberosity was 45.7°±6.9°. The angle between the surgical epicondylar axis and the line from tibial tuberosity to tibial center was 69°±8.3°. This close correlation (R=.73; P<.001) shows that the position of the fibular head determines femorotibial rotation. The fibular head may become a helpful landmark for establishing the rotation of the tibial component; it could be useful in interpretation of postoperative CT scans in knees suspected of tibial malrotation.  相似文献   
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Left ventricular function during interval and steady state exercise.   总被引:1,自引:0,他引:1  
PURPOSE: Interval training (INT) is a commonly used method of exercise training in both athletic and clinical populations. Although we generally understand left ventricular (LV) function during steady state (SS) exercise, there are no data regarding LV function during INT. METHODS: We studied eight healthy, physically active volunteers during upright cycle ergometry during 15 min of both SS and INT, at the same average power output (90% individual anaerobic threshold), using first pass radionuclide ventriculography. During INT (60s/60s), measures of LV function were made during work (220 W) after 4 and 12 min and during recovery (120 W) after 7 and 15 min. These were compared with the average of four temporally matched measures made during SS (170 W). RESULTS: During INT, LV ejection fraction increased from rest (67 +/- 6%) to 77 +/- 5, 80 +/- 5, 77 +/- 5 and 79 +/- 4% after 4, 7, 12, and 15 min, respectively. During SS, LV ejection fraction was not significantly different at rest (70 +/- 4%) or during exercise (76 +/- 4, 79 +/- 4, 80 +/- 3, and 81 +/- 3%) after 4, 7, 12, and 15 min, respectively. Other measures of LV function (HR, BP, LV volumes, cardiac output, systemic vascular resistance, peak emptying, and filling rates) were likewise similar during temporally matched measurements during INT and SS. CONCLUSIONS: Although there were the expected transitions of ejection fraction with work and recovery, the overall hemodynamic picture during INT was very similar to SS. These data suggest that LV function during INT is not substantially different to that during SS.  相似文献   
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AOPP-induced activation of human neutrophil and monocyte oxidative metabolism: A potential target forN-acetylcysteine treatment in dialysis patients. BACKGROUND: Oxidative stress largely contributes to hemodialysis-associated lethal complications, thus explaining the urgent need of antioxidant-based therapeutic strategies in hemodialysis patients. We previously identified advanced oxidation protein products (AOPP) in the uremic plasma as exquisite markers of oxidative stress and potent mediators of monocyte activation. The present study was aimed at searching whether (1) AOPP can also trigger activation of polymorphonuclear neutrophils (PMN), and (2) whether AOPP-induced activation could be inhibited by N-acetylcysteine (NAC), a widely used compound which has been shown to prevent oxidative injury to kidney. METHODS: Both human serum albumin (HAS) AOPP (i.e., HOCl-modified HSA in vitro preparations and AOPP extracted from plasma of hemodialysis patients) were tested for their capacity to trigger phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and myeloperoxidase (MPO)-dependent activities as measured by lucigenin- and luminol-amplified chemiluminescence (CL), respectively, as compared to receptor-dependent [opsonized zymosan or receptor-independent phorbol myristate acetate (PMA)]. The effect of PMN priming by platelet-activating factor (PAF), and the effect of NAC on normal monocyte and on normal or hemodialysis patient's (N = 16) PMN oxidative responses were compared. RESULTS: HSA-AOPP triggered in a HOCl dose-dependent manner both NADPH-oxidase- and MPO-dependent CL of PMN. This latter was further enhanced by PAF priming. Plasma-derived AOPP obtained from hemodialysis patients also triggered PMN respiratory burst. NAC significantly reduced HSA-AOPP-mediated responses of normal monocyte and of normal and uremic PMN but had no significant effect on opsonized zymosan- or PMA-induced CL responses. CONCLUSION: This dual potential of NAC to inhibit phagocyte oxidative responses induced by HSA-AOPP without affecting those mediated by compounds mimicking pathogens supports the proposal of a therapeutic trial with NAC aimed at reducing oxidative stress-related inflammation in hemodialysis patients.  相似文献   
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