We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux reactors.The filter burnup and singl...We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux reactors.The filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy range.The burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme curves.The three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were proven.The neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.展开更多
Hemodialysis (HD) is one type of procedure for eliminating toxic chemicals and infusing bicarbonate in patients with end-stage renal disease (ESRD). Research and development in the hemodialyzer industry have, hitherto...Hemodialysis (HD) is one type of procedure for eliminating toxic chemicals and infusing bicarbonate in patients with end-stage renal disease (ESRD). Research and development in the hemodialyzer industry have, hitherto, depended mostly on empirical evidence to optimize HD therapy. This is often costly and involves numerous clinical trials. Developing a comprehensive time-dependent mathematical model to examine the dynamic exchange of solutes (<span style="white-space:nowrap;">HC<span>O</span><sup>-</sup><sub style="margin-left:-6px;">3</sub></span> and pCO<sub>2</sub>), blood pH and H<sup>+</sup> ions in a prototype hollow-fiber hemodialyzer is essential in optimizing future design and improvement. A comprehensive mathematical model which is represented by a coupled set of transport equations and delineates the blood and dialyzate compartments of the hemodialyzer, and includes bicarbonate-buffering reaction in the blood channel and bicarbonate replenishment mechanism in the dialysate, is used to describe the time-dependent bulk concentration and exit concentration of solutes, blood pH and H<sup>+</sup> ions in the hollow-fiber prototype hemodialyzer. A numerical simulation of the model is used to test several time-dependent bulks and exit concentration profiles of solutes in the blood and dialyzate. Results obtained from the numerical solution of the model show the bulk and exit concentrations of solute at various distances along the blood and dialyzate channels at different times. This modeling exercise will also allow us in our next study to examine some physical mechanisms of the hemodialyzer.展开更多
Background: Dialyzable leukocyte extracts (DLE) are heterogeneous mixtures of peptides less than 10 kDa in size that are used as immunomodulatory adjuvants in immune-mediated diseases. TransferonTM is DLE manufactured...Background: Dialyzable leukocyte extracts (DLE) are heterogeneous mixtures of peptides less than 10 kDa in size that are used as immunomodulatory adjuvants in immune-mediated diseases. TransferonTM is DLE manufactured by National Polytechnic Institute (IPN), and is registered by Mexican health-regulatory authorities as an immunomodulatory drug and commercialized nationally. The proposed mechanism of action of TransferonTM is induction of a Th1 immunoregulatory response. Despite that it is widely used, to date there are no reports of adverse events related to the clinical safety of human DLE or TransferonTM. Objective: To assess the safety of TransferonTM in a large group of patients exposed to DLE as adjuvant treatment. Methods: We included in this study 3844 patients from our Clinical Immunology Service at the Unit of External Services and Clinical Research (USEIC), IPN. Analysis was performed from January 2014 to November 2014, searching for clinical adverse events in patients with immune-mediated diseases and treated with TransferonTM as an adjuvant. Results: In this work we observed clinical nonserious adverse events (AE) in 1.9% of patients treated with TransferonTM (MD 1.9, IQR 1.7 - 2.0). AE were 2.8 times more frequently observed in female than in male patients. The most common AE were headache in 15.7%, followed by rash in 11.4%, increased disease-related symptomatology in 10%, rhinorrhea in 7.1%, cough in 5.7%, and fatigue in 5.7% of patients with AE. 63% of adverse event presentation occurred from day 1 to day 4 of treatment with TransferonTM, and mean time resolution of adverse events was 14 days. In 23 cases, the therapy was stopped because of adverse events and no serious adverse events were observed in this study. Conclusion: TransferonTM induced low frequency of nonserious adverse events during adjuvant treatment. Further monitoring is advisable for different age and disease groups of patients.展开更多
Laser wakefield accelerators (LWFAs) are considered to be one of the most compeuuve next- generation accelerator candidates. In this paper, we will study the potential high-flux electron beam production of an LWFA d...Laser wakefield accelerators (LWFAs) are considered to be one of the most compeuuve next- generation accelerator candidates. In this paper, we will study the potential high-flux electron beam production of an LWFA driven by petawatt-level laser pulses. In our three-dimensional particle-in-cell simulations, an optimal set of parameters gives -40 nC of charge with 2 PW laser power, thus -400 kA of instantaneous current if we assume the electron beam duration is 100 fs. This high flux and its secondary radiation are widely applicable in nuclear and QED physics, industrial imaging, medical and biological studies.展开更多
Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecula...Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecular membrane material with excellent biocompatibility,stable mechanical properties,high temperature and pressure resistance,and good cleaning performance,which has been applied for more than 10 years.This trial is to assess the safety and efficacy of hollow polysulfone membrane fiber dialyzer with pattern number Enttex^(TM)-16LF(E60)for hemodialysis in patients with acute or chronic renal failure due to multiple factors.Methods Totally 76 patients receiving maintenance hemodialysis were included in a two-site,random,open label,two-stage,positive crossover and non inferiority validation study.The clinical efficacy and safety of the test device were observed,which was a hollow fiber dialyzer produced by Guangzhou Enttex Medical Products Co.,Ltd.,with polyethersulfone membrane imported from Germany.It was a low flux dialyzer with the pattern number of EnttexTM-16LF(E60).Inclusion criteria:①patients with acute or chronic renal failure due to various reasons who needed hemodialysis;②18 to 80 years old,gender unlimited;③patients who received stable dialysis for more than 3 months,regular hemodialysis 3 times a week,4 h at each time,blood flow rate of 200~350ml/min;④using bicarbonate dialysate at a flow rate of 500ml/min;⑤patients with arteriovenous fistula or who received artificial blood vessel puncture dialysis;received anticoagulation by heparin or low molecular weight heparin.Exclusion criteria:①patients needing heparin free dialysis for severe anemia,tumor and active bleeding;②patients with severe cardiac(gradeⅢcardiac function),hepatic(severe hepatitis and cirrhosis)and pulmonary diseases(severe respiratory failure).Results Comparison of parameters,including the changes of Kt/V,general creatinine and urea clearance rates and URR(urea reduction rate)shows no statistical significance in differences between the two devices,indicating that the test and control devices can equally and effectively eliminate toxins including creatinine and urea,etc.PPP and MITTP results are consistent.Comparison of ultrafiltration rates between two groups of patients shows no statistical difference.PPP and MITTP results are consistent,indicating that both the test device and control device can effectively eliminate water.In MITTP,electrolytes including K^+,Na^+,Cl^-,Ca^2+,HCO3^-,etc.show no statistical significance in difference between the test and control devices before and after dialysis(P>0.05).After treating by using test and control devices,body weight,serum potassium and phos-phorus all significantly decrease(P<0.001);serum Ca^2+,PO2,PCO2and HCO3^-all significantly increase(P<0.001).These results indicate that both the test and control devices can effectively eliminate serum potassium and phosphorus,and eliminate excess water in body,maintain the balance between liquid and electrolytes in patients.PPP and MITTP results are consistent.Conclusion This clinical trial confirms that hollow polyethersulfone membrane fiber dialyzer can be safely and effectively used in hemodialysis therapy.展开更多
Hemodialysis is the main method of clinical renal replacement therapy, and its effectiveness and safety have been widely confirmed. High-flux hemodialysis, as a constantly updating new mode in the field of blood purif...Hemodialysis is the main method of clinical renal replacement therapy, and its effectiveness and safety have been widely confirmed. High-flux hemodialysis, as a constantly updating new mode in the field of blood purification, has effectively improved the efficiency of hemodialysis and reduced the incidence of hemodialysis complications. High-flux hemodialysis has been widely used in clinical practice, and mainly plays its role through adsorption, convection and dispersion. High-flux hemodialysis has some advantages not possessed by conventional hemodialysis, including protecting injured renal function, reducing the incidence of cardiovascular complications in hemodialysis patients, improving the patients' nutritional status, reducing the occurrence of renal osteopathy and delaying the occurrence time of dialysis-associated amyloidosis. However, high-flux hemodialysis also has some limitations, such as the elimination of drugs and nutrients, and the backfiltration caused by increased pressure on the dialysis membrane and dialysate side. In this review, the related progress of high-flux hemodialysis in clinical application, mechanism, complications and treatment are discussed in order to provide a reference for its more rational clinical use.展开更多
Objective:To investigate the effects of high-flux hemodialysis on inflammatory factors and nutritional status in patients with severe renal failure.Methods:A total of 72 patients with severe renal failure who underwen...Objective:To investigate the effects of high-flux hemodialysis on inflammatory factors and nutritional status in patients with severe renal failure.Methods:A total of 72 patients with severe renal failure who underwent dialysis treatment in the hospital from January 2017 to March 2019 were selected as the research subjects,and they were randomly divided into 2 groups with 36 patients each.The control group underwent low-flux hemodialysis,and the observation group underwent high-flux hemodialysis.The levels of inflammatory factors and nutritional status were compared between the two groups after treatment.Results:The levels of various inflammatory factors in the observation group were lower than those in the control group and the nutritional indexes were higher than those in the control group after 4 weeks of treatment(P<0.05).Conclusion:High-throughput hemodialysis in patients with severe renal failure can significantly reduce the levels of inflammatory factors and improve nutritional status.展开更多
An experimental study of the gas-solid flow dynamics in the high-flux CFB riser was accomplished by analysing the scaling regions from solid concentration signals collected from a 76 mm internal diameters and 10 m hig...An experimental study of the gas-solid flow dynamics in the high-flux CFB riser was accomplished by analysing the scaling regions from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles of 67 μm mean diameter and 1500 kg/m3 density together with 70% to 80% humid air was used. Solid concentration data were analysed using codes prepared in FORTRAN 2008 to get correlation integrals at different embedding dimensions and operating conditions and plot their profiles. Scaling regions were identified by visual inspection method and their location on planes determined. Scaling regions were analysed based on operating conditions and riser spatial locations. It was found that scaling regions occupy different locations on the plane depending on the number of embedding dimensions and operating conditions. As the number of embedding dimensions increases the spacing between scaling regions decreases until it saturates towards higher embedding dimensions. Slopes of scaling regions increases with embedding dimensions until saturation where they become constant. Slopes of scaling regions towards the wall decrease while the number of scaling regions for a particular profile increases. The span of the scaling region is wider at the initial values of hyperspherical radius than its final values. The scaling regions in some flow development sections show multifractal behaviour for each embedding dimension which manifests into visible basin which is defined in this study as multifractal basin. Further, the end points of the scaling region for each correlation integral profile differ from each other as the embedding dimension changes. This study suggests that identification of scaling region by visual inspection method is useful in understanding the gas-solid flow dynamics in the High-Flux CFB riser system. Further studies are recommended on risers of different diameters and heights operated at low and high solid fluxes and different gas velocities for comparison or usage of time series of different signal types like pressure fluctuations.展开更多
The study of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using trajectory distances of the reconstructed attractors from solid concentration signals collected from a 76 mm internal diam...The study of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using trajectory distances of the reconstructed attractors from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3 together with 70% to 80% humid air was used. Solid concentration data were analyzed using codes prepared in FORTRAN 2008 to get trajectories of the reconstructed attractors and their distances apart. Trajectory distances were found to increase from the centre towards the wall indicating the expansion of the attractor. The probability density function (PDF) of the trajectory distances changes from single peak at the centre to multiple peaked profiles in the wall region. Multiple peaked profiles indicate multifractal flow behaviours. Cumulative distribution functions (CDF) of the trajectory distances changes from single S-shaped at the centre to multiple S-shaped profiles in some locations of the wall region indicating multifractal flow behaviours. The PDF distribution of these distances at the entrance section and in the wall region forms different types of statistical distributions showing differences in gas-solid flow structures in various spatial locations of the wall region and the entrance sections. Most of the distributions at the centre fall under the Gumbel max distribution for all flow development sections of the riser, especially at air velocities of 5.5 m/s and 8 m/s showing uniform flow structures. Further, it was found that increase of the number of the phase space reconstruction embedding dimension increases the trajectory distances between the state vectors leading to the expansion of the attractor.展开更多
Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating flui...Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s air velocity and 50 to 550 kg/m2s solids flux of spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3. Data were analyzed using prepared FORTRAN 2008 code to get correlation integral followed by determination of correlation dimensions with respect to the hyperspherical radius and their profiles, plots of which were studied. It was found that correlation dimension profiles at the centre have single peak with higher values than the wall region profiles. Towards the wall, these profiles have double or multiple peaks showing bifractal or multifractal flow behaviors. As the velocity increases the wall region profiles become random and irregular. Further it was found that, as the height increases the correlation dimension profiles shift towards higher hyperspherical radius at the centre and towards lower hyperspherical radius in the wall region at r/R = 0.81. The established method of mapping correlation dimension profiles in this study forms a suitable tool for analysis of high-flux riser dynamics compared to other analyses approaches. However, further analysis is recommended to other gas-solid CFB riser of different dimensions operated at high-flux conditions using the established method.展开更多
Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 pat...Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 patients were recruited from Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. The experiment was approved by the ethnical committee of Xinhua Hospital and under permissions fronl patients. All the patients were randomized into polyethersulfone group (PES, n=18) and polysulfone group (PS, n=18). Hemodialysis was given by using Fresenius 4008S capacity-controlled dialyser and ultra-purified bicarbonate dialysate, more than 3.5 h each time, three times per-week, followed by heparin anticoagulation for a week, three times totally. Changes in blood urea nitrogen (BUN), serum creatinine (Set), phosphate (p2+), hemoglobin and albumin levels were determined for the efficacy and safety evahlation. Results: The serum BUN, Set and p2+ concentrations significantly reduced after hemodialysis with different dialyzers, and the decrease amplitude of two groups was equivalent(P〉0.05). The clearance rate of the serum BUN and Scr had no significant difference among two groups(P〉O.05). The clearance rate (ml/min) of the sermn P^2+ was 144.57 ±27.83 v.s. 117.15 ±22.77 in two groups. The clearance rate of the serum p^2+ in PES group was more than that in PS group, and the difference was significant between two groups (P=0.0001). It was indicated that PES and PS membrane could efficiently eliminate serum mieromolecule solute in MHD patients, so PES membrane excelled PS membrane in eliminating serum p2+. The hemodialysis safety index, for example serum hemoglobin, albumin and blood pressure, had no significant difference between the two groups before and after hemodialysis (P〉0.05). Conclusion: The efficacy and safety of the PES hollow fiber membrane dialyzer is equivalent to that of the imported PS membrane dialyzer in hemodialysis for MHD patients. The PES membrane excels PS membrane in eliminating sermn p^2+.展开更多
Objective:To study the effect of high-flux and low-flux hemodialysis on the side metabolites and cytokines in patients with uremia.Methods: A total of 50 patients with uremia who accepted high-flux hemodialysis and 14...Objective:To study the effect of high-flux and low-flux hemodialysis on the side metabolites and cytokines in patients with uremia.Methods: A total of 50 patients with uremia who accepted high-flux hemodialysis and 140 patients with uremia who accepted low-flux hemodialysis in our hospital between March 2015 and March 2016 were selected and included in high-flux group and low-flux group respectively. Before and after dialysis, serum was collected respectively to determine the levels of side metabolites, calcium-phosphorus metabolism indexes and cytokines.Results: 3 months after dialysis, serum Ca levels of two groups of patients were not significantly different from those before dialysis while BUN, Scr,β2-MG, sTfR, P, PTH and AKP levels were significantly lower than those before dialysis;3 months after dialysis, serum BUN, Scr and Ca levels of high-flux group were not significantly different from those of low-flux group whileβ2-MG, sTfR, P, PTH, AKP, TNF-α, IL-1β, IL-6, IL-8 and IL-10 levels were significantly lower than those of low-flux group.Conclusion:Compared with low-flux hemodialysis, high-flux hemodialysis treatment of uremia can more effectively remove middle molecular and macromolecular toxins, correct calcium-phosphorus metabolism disorder and relieve micro-inflammatory state.展开更多
基金supported by Natural Science Foundation of China (No. 12305190)Lingchuang Research Project of China National Nuclear Corporation (CNNC)the Science and Technology on Reactor System Design Technology Laboratory
文摘We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux reactors.The filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy range.The burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme curves.The three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were proven.The neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.
文摘Hemodialysis (HD) is one type of procedure for eliminating toxic chemicals and infusing bicarbonate in patients with end-stage renal disease (ESRD). Research and development in the hemodialyzer industry have, hitherto, depended mostly on empirical evidence to optimize HD therapy. This is often costly and involves numerous clinical trials. Developing a comprehensive time-dependent mathematical model to examine the dynamic exchange of solutes (<span style="white-space:nowrap;">HC<span>O</span><sup>-</sup><sub style="margin-left:-6px;">3</sub></span> and pCO<sub>2</sub>), blood pH and H<sup>+</sup> ions in a prototype hollow-fiber hemodialyzer is essential in optimizing future design and improvement. A comprehensive mathematical model which is represented by a coupled set of transport equations and delineates the blood and dialyzate compartments of the hemodialyzer, and includes bicarbonate-buffering reaction in the blood channel and bicarbonate replenishment mechanism in the dialysate, is used to describe the time-dependent bulk concentration and exit concentration of solutes, blood pH and H<sup>+</sup> ions in the hollow-fiber prototype hemodialyzer. A numerical simulation of the model is used to test several time-dependent bulks and exit concentration profiles of solutes in the blood and dialyzate. Results obtained from the numerical solution of the model show the bulk and exit concentrations of solute at various distances along the blood and dialyzate channels at different times. This modeling exercise will also allow us in our next study to examine some physical mechanisms of the hemodialyzer.
文摘Background: Dialyzable leukocyte extracts (DLE) are heterogeneous mixtures of peptides less than 10 kDa in size that are used as immunomodulatory adjuvants in immune-mediated diseases. TransferonTM is DLE manufactured by National Polytechnic Institute (IPN), and is registered by Mexican health-regulatory authorities as an immunomodulatory drug and commercialized nationally. The proposed mechanism of action of TransferonTM is induction of a Th1 immunoregulatory response. Despite that it is widely used, to date there are no reports of adverse events related to the clinical safety of human DLE or TransferonTM. Objective: To assess the safety of TransferonTM in a large group of patients exposed to DLE as adjuvant treatment. Methods: We included in this study 3844 patients from our Clinical Immunology Service at the Unit of External Services and Clinical Research (USEIC), IPN. Analysis was performed from January 2014 to November 2014, searching for clinical adverse events in patients with immune-mediated diseases and treated with TransferonTM as an adjuvant. Results: In this work we observed clinical nonserious adverse events (AE) in 1.9% of patients treated with TransferonTM (MD 1.9, IQR 1.7 - 2.0). AE were 2.8 times more frequently observed in female than in male patients. The most common AE were headache in 15.7%, followed by rash in 11.4%, increased disease-related symptomatology in 10%, rhinorrhea in 7.1%, cough in 5.7%, and fatigue in 5.7% of patients with AE. 63% of adverse event presentation occurred from day 1 to day 4 of treatment with TransferonTM, and mean time resolution of adverse events was 14 days. In 23 cases, the therapy was stopped because of adverse events and no serious adverse events were observed in this study. Conclusion: TransferonTM induced low frequency of nonserious adverse events during adjuvant treatment. Further monitoring is advisable for different age and disease groups of patients.
基金supported by Extreme Light Infrastructure- Nuclear Physics (ELI-NP) Phase Ⅱa project co-financed by the Romanian Government and European Union through the European Regional Development FundThe EPOCH code project was funded by the UK EPSRC grants EP/G054950/1, EP/ G056803/1, EP/G055165/1 and EP/ M022463/1
文摘Laser wakefield accelerators (LWFAs) are considered to be one of the most compeuuve next- generation accelerator candidates. In this paper, we will study the potential high-flux electron beam production of an LWFA driven by petawatt-level laser pulses. In our three-dimensional particle-in-cell simulations, an optimal set of parameters gives -40 nC of charge with 2 PW laser power, thus -400 kA of instantaneous current if we assume the electron beam duration is 100 fs. This high flux and its secondary radiation are widely applicable in nuclear and QED physics, industrial imaging, medical and biological studies.
基金Guangdong Provincial Science and Technology Department Fund Project(507204531040)Guangdong Provincial Science and Technology Plan Fund Project(2013b9040004)
文摘Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecular membrane material with excellent biocompatibility,stable mechanical properties,high temperature and pressure resistance,and good cleaning performance,which has been applied for more than 10 years.This trial is to assess the safety and efficacy of hollow polysulfone membrane fiber dialyzer with pattern number Enttex^(TM)-16LF(E60)for hemodialysis in patients with acute or chronic renal failure due to multiple factors.Methods Totally 76 patients receiving maintenance hemodialysis were included in a two-site,random,open label,two-stage,positive crossover and non inferiority validation study.The clinical efficacy and safety of the test device were observed,which was a hollow fiber dialyzer produced by Guangzhou Enttex Medical Products Co.,Ltd.,with polyethersulfone membrane imported from Germany.It was a low flux dialyzer with the pattern number of EnttexTM-16LF(E60).Inclusion criteria:①patients with acute or chronic renal failure due to various reasons who needed hemodialysis;②18 to 80 years old,gender unlimited;③patients who received stable dialysis for more than 3 months,regular hemodialysis 3 times a week,4 h at each time,blood flow rate of 200~350ml/min;④using bicarbonate dialysate at a flow rate of 500ml/min;⑤patients with arteriovenous fistula or who received artificial blood vessel puncture dialysis;received anticoagulation by heparin or low molecular weight heparin.Exclusion criteria:①patients needing heparin free dialysis for severe anemia,tumor and active bleeding;②patients with severe cardiac(gradeⅢcardiac function),hepatic(severe hepatitis and cirrhosis)and pulmonary diseases(severe respiratory failure).Results Comparison of parameters,including the changes of Kt/V,general creatinine and urea clearance rates and URR(urea reduction rate)shows no statistical significance in differences between the two devices,indicating that the test and control devices can equally and effectively eliminate toxins including creatinine and urea,etc.PPP and MITTP results are consistent.Comparison of ultrafiltration rates between two groups of patients shows no statistical difference.PPP and MITTP results are consistent,indicating that both the test device and control device can effectively eliminate water.In MITTP,electrolytes including K^+,Na^+,Cl^-,Ca^2+,HCO3^-,etc.show no statistical significance in difference between the test and control devices before and after dialysis(P>0.05).After treating by using test and control devices,body weight,serum potassium and phos-phorus all significantly decrease(P<0.001);serum Ca^2+,PO2,PCO2and HCO3^-all significantly increase(P<0.001).These results indicate that both the test and control devices can effectively eliminate serum potassium and phosphorus,and eliminate excess water in body,maintain the balance between liquid and electrolytes in patients.PPP and MITTP results are consistent.Conclusion This clinical trial confirms that hollow polyethersulfone membrane fiber dialyzer can be safely and effectively used in hemodialysis therapy.
文摘Hemodialysis is the main method of clinical renal replacement therapy, and its effectiveness and safety have been widely confirmed. High-flux hemodialysis, as a constantly updating new mode in the field of blood purification, has effectively improved the efficiency of hemodialysis and reduced the incidence of hemodialysis complications. High-flux hemodialysis has been widely used in clinical practice, and mainly plays its role through adsorption, convection and dispersion. High-flux hemodialysis has some advantages not possessed by conventional hemodialysis, including protecting injured renal function, reducing the incidence of cardiovascular complications in hemodialysis patients, improving the patients' nutritional status, reducing the occurrence of renal osteopathy and delaying the occurrence time of dialysis-associated amyloidosis. However, high-flux hemodialysis also has some limitations, such as the elimination of drugs and nutrients, and the backfiltration caused by increased pressure on the dialysis membrane and dialysate side. In this review, the related progress of high-flux hemodialysis in clinical application, mechanism, complications and treatment are discussed in order to provide a reference for its more rational clinical use.
文摘Objective:To investigate the effects of high-flux hemodialysis on inflammatory factors and nutritional status in patients with severe renal failure.Methods:A total of 72 patients with severe renal failure who underwent dialysis treatment in the hospital from January 2017 to March 2019 were selected as the research subjects,and they were randomly divided into 2 groups with 36 patients each.The control group underwent low-flux hemodialysis,and the observation group underwent high-flux hemodialysis.The levels of inflammatory factors and nutritional status were compared between the two groups after treatment.Results:The levels of various inflammatory factors in the observation group were lower than those in the control group and the nutritional indexes were higher than those in the control group after 4 weeks of treatment(P<0.05).Conclusion:High-throughput hemodialysis in patients with severe renal failure can significantly reduce the levels of inflammatory factors and improve nutritional status.
文摘An experimental study of the gas-solid flow dynamics in the high-flux CFB riser was accomplished by analysing the scaling regions from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles of 67 μm mean diameter and 1500 kg/m3 density together with 70% to 80% humid air was used. Solid concentration data were analysed using codes prepared in FORTRAN 2008 to get correlation integrals at different embedding dimensions and operating conditions and plot their profiles. Scaling regions were identified by visual inspection method and their location on planes determined. Scaling regions were analysed based on operating conditions and riser spatial locations. It was found that scaling regions occupy different locations on the plane depending on the number of embedding dimensions and operating conditions. As the number of embedding dimensions increases the spacing between scaling regions decreases until it saturates towards higher embedding dimensions. Slopes of scaling regions increases with embedding dimensions until saturation where they become constant. Slopes of scaling regions towards the wall decrease while the number of scaling regions for a particular profile increases. The span of the scaling region is wider at the initial values of hyperspherical radius than its final values. The scaling regions in some flow development sections show multifractal behaviour for each embedding dimension which manifests into visible basin which is defined in this study as multifractal basin. Further, the end points of the scaling region for each correlation integral profile differ from each other as the embedding dimension changes. This study suggests that identification of scaling region by visual inspection method is useful in understanding the gas-solid flow dynamics in the High-Flux CFB riser system. Further studies are recommended on risers of different diameters and heights operated at low and high solid fluxes and different gas velocities for comparison or usage of time series of different signal types like pressure fluctuations.
文摘The study of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using trajectory distances of the reconstructed attractors from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3 together with 70% to 80% humid air was used. Solid concentration data were analyzed using codes prepared in FORTRAN 2008 to get trajectories of the reconstructed attractors and their distances apart. Trajectory distances were found to increase from the centre towards the wall indicating the expansion of the attractor. The probability density function (PDF) of the trajectory distances changes from single peak at the centre to multiple peaked profiles in the wall region. Multiple peaked profiles indicate multifractal flow behaviours. Cumulative distribution functions (CDF) of the trajectory distances changes from single S-shaped at the centre to multiple S-shaped profiles in some locations of the wall region indicating multifractal flow behaviours. The PDF distribution of these distances at the entrance section and in the wall region forms different types of statistical distributions showing differences in gas-solid flow structures in various spatial locations of the wall region and the entrance sections. Most of the distributions at the centre fall under the Gumbel max distribution for all flow development sections of the riser, especially at air velocities of 5.5 m/s and 8 m/s showing uniform flow structures. Further, it was found that increase of the number of the phase space reconstruction embedding dimension increases the trajectory distances between the state vectors leading to the expansion of the attractor.
文摘Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s air velocity and 50 to 550 kg/m2s solids flux of spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3. Data were analyzed using prepared FORTRAN 2008 code to get correlation integral followed by determination of correlation dimensions with respect to the hyperspherical radius and their profiles, plots of which were studied. It was found that correlation dimension profiles at the centre have single peak with higher values than the wall region profiles. Towards the wall, these profiles have double or multiple peaks showing bifractal or multifractal flow behaviors. As the velocity increases the wall region profiles become random and irregular. Further it was found that, as the height increases the correlation dimension profiles shift towards higher hyperspherical radius at the centre and towards lower hyperspherical radius in the wall region at r/R = 0.81. The established method of mapping correlation dimension profiles in this study forms a suitable tool for analysis of high-flux riser dynamics compared to other analyses approaches. However, further analysis is recommended to other gas-solid CFB riser of different dimensions operated at high-flux conditions using the established method.
文摘Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 patients were recruited from Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. The experiment was approved by the ethnical committee of Xinhua Hospital and under permissions fronl patients. All the patients were randomized into polyethersulfone group (PES, n=18) and polysulfone group (PS, n=18). Hemodialysis was given by using Fresenius 4008S capacity-controlled dialyser and ultra-purified bicarbonate dialysate, more than 3.5 h each time, three times per-week, followed by heparin anticoagulation for a week, three times totally. Changes in blood urea nitrogen (BUN), serum creatinine (Set), phosphate (p2+), hemoglobin and albumin levels were determined for the efficacy and safety evahlation. Results: The serum BUN, Set and p2+ concentrations significantly reduced after hemodialysis with different dialyzers, and the decrease amplitude of two groups was equivalent(P〉0.05). The clearance rate of the serum BUN and Scr had no significant difference among two groups(P〉O.05). The clearance rate (ml/min) of the sermn P^2+ was 144.57 ±27.83 v.s. 117.15 ±22.77 in two groups. The clearance rate of the serum p^2+ in PES group was more than that in PS group, and the difference was significant between two groups (P=0.0001). It was indicated that PES and PS membrane could efficiently eliminate serum mieromolecule solute in MHD patients, so PES membrane excelled PS membrane in eliminating serum p2+. The hemodialysis safety index, for example serum hemoglobin, albumin and blood pressure, had no significant difference between the two groups before and after hemodialysis (P〉0.05). Conclusion: The efficacy and safety of the PES hollow fiber membrane dialyzer is equivalent to that of the imported PS membrane dialyzer in hemodialysis for MHD patients. The PES membrane excels PS membrane in eliminating sermn p^2+.
文摘Objective:To study the effect of high-flux and low-flux hemodialysis on the side metabolites and cytokines in patients with uremia.Methods: A total of 50 patients with uremia who accepted high-flux hemodialysis and 140 patients with uremia who accepted low-flux hemodialysis in our hospital between March 2015 and March 2016 were selected and included in high-flux group and low-flux group respectively. Before and after dialysis, serum was collected respectively to determine the levels of side metabolites, calcium-phosphorus metabolism indexes and cytokines.Results: 3 months after dialysis, serum Ca levels of two groups of patients were not significantly different from those before dialysis while BUN, Scr,β2-MG, sTfR, P, PTH and AKP levels were significantly lower than those before dialysis;3 months after dialysis, serum BUN, Scr and Ca levels of high-flux group were not significantly different from those of low-flux group whileβ2-MG, sTfR, P, PTH, AKP, TNF-α, IL-1β, IL-6, IL-8 and IL-10 levels were significantly lower than those of low-flux group.Conclusion:Compared with low-flux hemodialysis, high-flux hemodialysis treatment of uremia can more effectively remove middle molecular and macromolecular toxins, correct calcium-phosphorus metabolism disorder and relieve micro-inflammatory state.