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排序方式: 共有345条查询结果,搜索用时 15 毫秒
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Silverio Rotondi Adolfo Perrotta Giovanni Pintus Laura Capasso Marzia Pasquali Alessio Farcomeni Emanuela Paoloni Sandro Mazzaferro Lida Tartaglione 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(4):370-377
Introduction
Vascular access recirculation during hemodialysis is associated with reduced effectiveness and worse survival outcomes. To evaluate recirculation, an increase in pCO2 in the blood of the arterial line during hemodialysis (threshold of 4.5 mmHg) was proposed. The blood returning from the dialyzer in the venous line has significantly higher pCO2, so in the presence of recirculation, pCO2 in the arterial blood line may increase (ΔpCO2) during hemodialysis sessions. The aim of our study was to evaluate ΔpCO2 as a diagnostic tool for vascular access recirculation in chronic hemodialysis patients.Methods
We evaluated vascular access recirculation with ΔpCO2 and compared it with the results of a urea recirculation test, which is the gold standard. ΔpCO2 was obtained from the difference in pCO2 in the arterial line at baseline (pCO2T1) and after 5 min of hemodialysis (pCO2T2). ∆pCO2 = pCO2T2–pCO2T1.Findings
In 70 hemodialysis patients (mean age: 70.52 ± 13.97 years; hemodialysis vintage of 41.36 ± 34.54, KT/V 1.4 ± 0.3), ∆pCO2 was 4 ± 4 mmHg, and urea recirculation was 7% ± 9%. Vascular access recirculation was identified using both methods in 17 of 70 patients, who showed a ∆pCO2 of 10 ± 5 mmHg and urea recirculation of 20% ± 9%; time in months of hemodialysis was the only difference between vascular access recirculation and non-vascular access recirculation patients (22 ± 19 vs. 46 ± 36, p: 0.05). In the non-vascular access recirculation group, the average ΔpCO2 was 1.9 ± 2 (p: 0.001), and the urea recirculation % was 2.8 ± 3 (p: 0.001). The ΔpCO2 correlated with the urea recirculation % (R: 0.728; p < 0.001).Discussion
ΔpCO2 in the arterial blood line during hemodialysis is an effective and reliable diagnostic tool for identifying recirculation of the vascular access but not its magnitude. The ΔpCO2 test application is simple and economical and does not require special equipment. 相似文献275.
Peer review versus bibliometrics: Which method better predicts the scholarly impact of publications?
Scientometrics - In this work, we try to answer the question of which method, peer review versus bibliometrics, better predicts the future overall scholarly impact of scientific publications. We... 相似文献
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D'Agostino A Errico ME Malinconico M De Rosa M Avella M Schiraldi C 《Journal of materials science. Materials in medicine》2011,22(3):481-490
In this research work organic/inorganic nano composites were synthesized from poly-2-hydroxyethylmethacrylate and properly
modified silica nanoparticles by in situ polymerization. In particular, fumed nanosilica was functionalized with methacryloylpropyltrimetoxy
silane (MPTMS) in order to obtain a more homogeneous, reliable and mechanically performing nano composite. For comparison,
nano composites with non functionalised silica were also prepared. Scanning electron microscopy was performed in order to
visualize the effects of functionalization on the mode and state of dispersion. This analysis demonstrated that MPTMS grafted
onto silica surface acts as an effective coupling agent and assures a good dispersion and distribution of nanoparticles as
well as a strong nano particle/matrix interfacial adhesion. As a result of strong interactions occurring between phases, a
pronounced increase of the glass transition temperature and mechanical parameters were recorded. Finally, these novel nano
composites were seeded with murine fibroblast and human mesenchymal stem cells, and observed in time-lapse experiments proving
an effective biological response. 相似文献
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Alessandro Passardi Emanuela Scarpi Paola Ulivi 《International journal of molecular sciences》2021,22(14)
The present editorial aims to summarise the six scientific papers that have contributed to this Special Issue, focusing on different aspects of molecular and translational research on colorectal cancer. We believe that the present Special Issue might contribute to the expansion of the current knowledge concerning potential molecular predictive and/or prognostic biomarkers in CRC, as well as new targets for anticancer treatment. This may help in identifying new strategies to improve diagnostic and therapeutic approaches. 相似文献
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Romolo Marcelli Emanuela Proietti Giancarlo Bartolucci Andrea Lucibello Giorgio De Angelis Gianluca Muzi Janos Solymosi 《Analog Integrated Circuits and Signal Processing》2013,75(3):407-415
In this paper Coupled Triangular Resonators in coplanar waveguide have been studied for S (2–4 GHz) and C (4–8 GHz) Band microwave applications. The peculiarity of the triangular structure to exhibit multiple resonances is usually proposed for dual and three-band purposes, to obtain efficient unit cells for high performance microwave tunable oscillators. One more characteristic of the triangular shape is the meta-material behavior, which allows a significant size decrease of the device. Coupled resonating configurations are proposed in this contribution, to be manufactured in Microsystem Technology by using polymeric layers as spacers between individual resonators organized in a vertical stack. Electromagnetic simulations have been performed to study narrow-band filters characterized by reduced dimensions, low insertion loss and steep band edges. Lumped element models are presented which can be easily implemented in commercial circuital software packages for the design of networks using these resonators. 相似文献