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991.

Background and objective

Increased left ventricular mass (LVM), low ventricular ejection fraction (EF), and high pulse-wave velocity (PWV) relate to overall and cardiovascular mortality in patients with ESRD. The aim of this study was to determine the effect of online hemodiafiltration (HDF) versus low-flux hemodialysis (HD) on LVM, EF, and PWV.

Design, setting, participants, & measurements

Echocardiography was used to assess LVM and EF in 342 patients in the CONvective TRAnsport STudy followed for up to 4 years. PWV was measured in 189 patients for up to 3 years. Effect of HDF versus HD on LVM, EF, and PWV was evaluated using linear mixed models.

Results

Patients had a mean age of 63 years, and 61% were male. At baseline, median LVM was 227 g (interquartile range [IQR], 183–279 g), and median EF was 65% (IQR, 55%–72%). Median PWV was 9.8 m/s (IQR, 7.5–12.0 m/s). There was no significant difference between the HDF and HD treatment groups in rate of change in LVM (HDF: change, −0.9 g/yr [95% confidence interval (95% CI), −8.9 to 7.7 g]; HD: change, 12.5 g/yr [95% CI, −3.0 to 27.5 g]; P for difference=0.13), EF (HDF: change, −0.3%/yr [95% CI, −2.3% to 1.8%]; HD: change, −3.4%/yr [95% CI, −5.9% to −0.9%]; P=0.17), or PWV (HDF: change, −0.0 m/s per year [95% CI, −0.4 to 0.4 m/s); HD: change, 0.0 m/s per year [95% CI, −0.3 to 0.2 m/s]; P=0.89). No differences in rate of change between treatment groups were observed for subgroups of age, sex, residual kidney function, dialysis vintage, history of cardiovascular disease, diabetes, or convection volume.

Conclusions

Treatment with online HDF did not affect changes in LVM, EF, or PWV over time compared with HD.  相似文献   
992.
993.
There is limited information regarding the performance of tests for direct oral anticoagulants (DOACs). To generate more knowledge, the accuracy of DOAC tests were evaluated using external quality assessment data from multiple years. This data demonstrated a good correlation for the tests with a small overall interlaboratory variability (10% for dabigatran, rivaroxaban and apixaban and 12% for edoxaban). The greatest differences between the various reagents were observed for rivaroxaban, especially for concentrations below 100 ng/ml. In conclusion, the results show overall reliable DOAC levels with some differences between reagent groups. Important finding: clinical decision criteria could be affected by the choice of reagent.  相似文献   
994.
The differences in energy metabolism of the myocardium in children with congenital cardiac malformations producing hypoxaemia (arterial oxygen saturation 77 +/- 2%) or normoxaemia (arterial oxygen saturation 94 +/- 2%) were analysed by measuring the activity of the representative energy-supplying enzymes. Right atrial and ventricular tissue samples were obtained during surgical interventions. We demonstrated that myocardial metabolism was significantly influenced by hypoxaemia: the aerobic capacity of the energetic metabolism was reduced both in the atriums and ventricles. Atrial myocardium was more affected: in addition to citrate synthase, the activity of enzymes connected with lactate uptake and carbohydrate catabolism was also significantly decreased. These results demonstrate that the human heart is able to adapt to hypoxaemia by changing its energetic metabolism.  相似文献   
995.
Bacteria- and Endotoxin-Free Dialysis Fluid for Use in Chronic Hemodialysis   总被引:3,自引:0,他引:3  
Abstract: As the quality of water in the dialysis fluid varies considerably, dialysis fluid is contaminated with a high percentage of bacteria and endotoxins. The bacterial populations contained in the dialysis fluid are as heterogeneous as the chemical structure of the endotoxins that result. The latter can pass through the dialysis membrane whereby high-flux membranes permit a larger number of retransportable molecules than low-flux membranes. A central aim toward a future, safe dialysis process should, therefore, be the production of a dialysate that is free of bacteria and endotoxins. As we were able to demonstrate in various examinations, this goal is most likely to be achieved with the aid of sterile filtration using hollow fiber modules of polyamid. To avoid disinfection of the polyamid membrane, as this would only reach bacteria but not endotoxins, the filter was changed after at most 10 h. The achieved dialysis fluid was free of bacteria and endotoxins. We were also able to show that the release of interleukin-1 was reduced. In addition, side-effects, such as a drop in blood pressure, headaches, muscular cramps, and nausea, were reduced.  相似文献   
996.
OBJECTIVES: To investigate whether exercise alone or as a part of a multidisciplinary treatment reduces sick leave in patients with non-specific non-acute low back pain. METHODS: A meta-analysis of randomized controlled trials was performed. A qualitative analysis of the sick leave results was performed applying pre-defined levels of evidence. In studies comparing exercise with usual care, pooled effect sizes were computed. RESULTS: Fourteen trials were identified allowing 22 comparisons between treatments. The qualitative and the quantitative analysis showed strong evidence that exercise reduces sick days during the first follow-up year, the effect size (95% confidence interval) was -0.24 ( -0.36, -0.11). In a subgroup of studies on the treatment of severely disabled patients (> 90 sick days under usual care) the effect size was -0.30 (-0.42, -0.17). The effect size of the number of patients receiving a disability allowance was small and not significant. CONCLUSION: The reviewed trials provide strong evidence that exercise significantly reduces sick days during the first follow-up year.  相似文献   
997.
998.
Inflammatory mechanisms in Alzheimer's disease   总被引:2,自引:0,他引:2  
Alzheimer's disease is aetiologically heterogeneous, but the pathogenesis is often considered to be initiated by the deposition of amyloid fibrils, followed by neuritic tau pathology and neuronal death. A variety of inflammatory proteins has been identified in the brains of patients with Alzheimer's disease postmortem. In this article, Piet Eikelenboom and colleagues review evidence to suggest that the inflammatory processes are intimately involved in several crucial events in the pathological cascade. This suggests possibilities for the treatment of Alzheimer's disease with anti-inflammatory drugs.  相似文献   
999.
In a prospective study of 27 shoulders with recurrent anterior dislocation, we compared six radiographic views for demonstration of the Hill-Sachs defect and the Bankart lesion. The Hill-Sachs defect was most often identified by the Stryker notch view (25/27); it was best visualized and most easily recognized on the 45 degrees craniocaudal view (22/27). This view also had the highest diagnostic yield for demonstrating the Bankart lesion.  相似文献   
1000.
Interferon was induced in leukocyte suspensions from human buffy coats by exposure to phytohemagglutinin P, concanavalin A (Con A) and staphylococcal enterotoxin A, under a variety of cell culture conditions. Con A was found to rapidly (within 12 h) induce high yields of antiviral activity (1.5 units/1000 cells). Lesser yields were obtained with the other two mitogens studied. The interferon was partially purified to a spec. act. around 105.3 units/mg protein, by batch adsorption on controlled-pore glass (CPG) beads and desorption by ethylene glycol. This material was characterized as containing mainly γ-type interferon. Specifically on gel filtration, a fraction of 45 000 daltons was obtained which could account for virtually all antiviral activity present in the starting material. Furthermore, the ethylene glycol-eluted antiviral activity was acid-labile, serologically distinct from a and β-type interferon and strictly species-specific (no activity detectable on any of the available cell species sensitive to α and β-type interferon). The crude culture supernatant also contained some antiviral activity which resembled β-type interferon in that it adsorbed to CPG, could be desorbed by pH 2 buffer, was acid-resistant and could be neutralized by a specific anti-fibroblast interferon antiserum. The CPG/ethylene glycol-purified γ-type interferon preparation was found to inhibit the growth of certain lymphoblastoid cells (Daudi and Molt-4). It also potentiated natural killer activity of fresh donor lymphocytes. In both respects, the γ-type interferon preparation was not significantly more active than preparations of a and β-interferon of similar antiviral potency.  相似文献   
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