The use of cooled dialysate temperatures first came about in the early 1980s as a way to curb the incidence of intradialytic hypotension （IDH）. IDH was then, and it remains today, the most common complication affect...The use of cooled dialysate temperatures first came about in the early 1980s as a way to curb the incidence of intradialytic hypotension （IDH）. IDH was then, and it remains today, the most common complication affecting chronic hemodialysis patients. It decreases quality of life on dialysis and is an independent risk factor for mortality. Cooling dialysate was first employed as a technique to incite peripheral vasoconstriction on dialysis and in turn reduce the incidence of intradialytic hypotension. Although it has become a common practice amongst in-center hemodialysis units, cooled dialysate results in up to 70% of patients feeling cold while on dialysis and some even experience shivering. Over the years, various studies have been performed to evaluate the safety and effcacy of cooled dialysate in comparison to a standard, more thermoneutral dialysate temperature of 37℃. Although these studies are limited by small sample size, they are promising in many aspects. They demonstrated that cooled dialysis is safe and equally efficacious as thermoneutral dialysis. Although patients report feeling cold on dialysis, they also report increased energy and an improvement in their overall health following cooled dialysis. They established that cooling dialysate temperatures improves hemodynamic tolerability during and after hemodialysis, even in patients prone to IDH, and does so without adversely affecting dialysis adequacy. Cooled dialysis also reduces the incidence of IDH and has a protective effect over major organs including the heart and brain. Finally, it is an inexpensive measure that decreases economic burden by reducing necessary nursing intervention for issues that arise on hemodialysis such as IDH. Before cooled dialysate becomes standard of care for patients on chronic hemodialysis, larger studies with longer follow-up periods will need to take place to confrm the encouraging outcomes mentioned here.展开更多
Dear Editor： There is accumulating evidence that human blood electronic circuit components and their application circuits become more and more important to cyborg implant/engineering, man-machine interface, hu- man ...Dear Editor： There is accumulating evidence that human blood electronic circuit components and their application circuits become more and more important to cyborg implant/engineering, man-machine interface, hu- man disease detection and healing, and artificial brain evolutionusl. Here, we report the first development of human plasma-based amplifier circuit in the dis- crete as well as integrated circuit （IC） configuration mode. Electrolytes in the human blood contain an enormous number of charge carriers such as positive and negative molecule/atom ions, which are electri- cally conducting media and therefore can be utilized for developing electronic circuit components and their application circuits. These electronic circuits obvi- ously have very high application impact potential towards bio-medical engineering and medical science and technology.展开更多
Glow discharge was utilized to add oxygen functional groups to the graphene platelets sample produced in chemical exfoliation synthesis. It was concluded based on Raman spectra that the graphene sample treated with th...Glow discharge was utilized to add oxygen functional groups to the graphene platelets sample produced in chemical exfoliation synthesis. It was concluded based on Raman spectra that the graphene sample treated with the glow discharge preserves specific graphene features while no transformation to amorphous carbon is happening. SEM and EDS results indicated the increases of oxygen content in the graphene sample after the exposure to the glow discharge. Raman spectra also support the fact that the graphene platelets have been decorated with oxygen as the result of the glow discharge treatment.展开更多
Objective To study the solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate for hemodialysis in patients with high risk of bleeding. Methods Forty-two kidney failure patients with h...Objective To study the solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate for hemodialysis in patients with high risk of bleeding. Methods Forty-two kidney failure patients with high risk of bleeding were divided into two groups (Group A and Group B) according to their hemodialysis manners. Patients in Group A were hemodialyzed with bicarbonate hemodialysate with low-molecular-weight heparin (dalteparin) anticoagulation and those in Group B with the new citrate anticoagulation hemodialysate prepared in our hospital without any other anticoagulant. Blood urea nitrogen (BUN) and creatinine (Cr) concentrations were measured before and after dialysis, and Kt/V and urea reduction rate (URR) were calculated. In addition, activated clotting time (ACT) and ionized calcium (iCa2+) concentration were also measured at the arterial and venous ends. Results ACT was extended and iCa2+ concentration decreased significantly at the venous end compared with those at the arterial end in Group B (P<0.01). BUN and Cr concentrations were markedly decreased after dialysis compared with those before dialysis in both groups (P<0.01), and no significant difference in solute clearance effect, as indicated by Kt/V and URR, was observed between Group A and Group B (P>0.05). Conclusion The solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate is excellent during hemodialysis in kidney failure patients with high risk of bleeding.展开更多
Objective：This study aims to investigate the effect of 4 different dialysate temperatures on blood pressure during hemodialysis for patients with hypertension.Methods：Using a self-controlled method,the patients＇ bo...Objective：This study aims to investigate the effect of 4 different dialysate temperatures on blood pressure during hemodialysis for patients with hypertension.Methods：Using a self-controlled method,the patients＇ body temperature was set as T.Accordingly,the dialysate temperature was set as 37 ℃,T＋0.5 ℃,T,and T-0.5 ℃.The changes in blood pressure,heart rate,mean arterial pressure and dialysis-induced adverse reactions at the 4 different dialysate temperatures were consistently monitored.Results：Patients who received hemodialysis with 37 ℃ and T＋0.5 ℃ dialysate demonstrated an unstable blood pressure and a higher incidence of adverse reactions,Patients who received hemodialysis with T and T-0.5 ℃ dialysate showed a relatively stable blood pressure,heart rate,and mean arterial pressure during dialysis.In particular,dialysate at T-0.5 ℃ resulted in the most stable blood pressure,the fewest adverse reactions and the best self-assessed comfort scores（P 〈 0.01）.Conclusions：The dialysate temperature during hemodialysis for patients with hypertension should be set to a temperature based on patients＇ preoperative body temperate T or 0.5 ℃ below T.This practice is suggested to enhance the stability of patients＇ blood pressure and heart rate during hemodialysis,reduce complications and improve patients＇ tolerance of hemodialysis.展开更多
<strong>Background.</strong> Intradialytic hypertension, a paradoxical rise in systolic blood pressure from pre- to postdialysis, is a poorly understood and difficult-to-treat phenomenon. We examined the e...<strong>Background.</strong> Intradialytic hypertension, a paradoxical rise in systolic blood pressure from pre- to postdialysis, is a poorly understood and difficult-to-treat phenomenon. We examined the effects of individually adjusted isonatremic and hyponatremic dialysate on intradialytic and interdialytic blood pressure in patients with intradialytic hypertension. <strong>Methods.</strong> We enrolled 11 patients with intradialytic hypertension in a prospective randomized cross-over study, with 4 treatment periods of different dialysate sodium concentrations. Period 1 (run-in) and 3 (wash-out) were standardized at 140 mEq/L;period 2 and 4 with iso- or hyponatremic sodium dialysate. Blood pressure was recorded each dialysis session, and 24-hour ambulatory blood pressure monitoring was performed at the end of each treatment period. <strong>Results.</strong> Isonatremic and hyponatremic dialysate were associated with significantly lower pre- and post-dialysis blood pressure as compared to baseline 140 mEq/L dialysate (predialysis 148.3 ± 24.7/67.7 ± 12.0 and 144.4 ± 16.5/68.8 ± 13.3 vs. 158.0 ± 18.3/75.6 ± 11.4 mmHg, resp p = 0.04 and 0.007 for systolic and p = 0.004 and 0.04 for diastolic blood pressure;postdialysis 154.2 ± 25.5/76.6 ± 14.1 and 142.5 ± 20.7/73.0 ± 12.9 vs. 159.1 ± 21.6/80.3 ± 12.1 mmHg, resp NS and p = 0.01 for systolic and NS and p = 0.04 for diastolic blood pressure). Postdialysis and 24 h systolic blood pressure tended to be lower with hyponatremic compared to isonatremic dialysate. <strong>Conclusion.</strong> Individually tailoring dialysate sodium concentration, based on the sodium set-point of each patient, resulted in a lower pre- and post-dialysis blood pressure in patients with intradialytic hypertension. 24 h blood pressure values tended to be lower as well with hyponatremic dialysate.展开更多
For stealth technology,in order to overcome the limitations of thin-layer plasma for electromagnetic waves attenuation and further broaden the radar cross-section(RCS)reduction(RCSR)band of the metasurface,the plasma-...For stealth technology,in order to overcome the limitations of thin-layer plasma for electromagnetic waves attenuation and further broaden the radar cross-section(RCS)reduction(RCSR)band of the metasurface,the plasma-based checkerboard metasurface composed of plasma and checkerboard metasurface is investigated to achieve better RCSR.We designed a checkerboard metasurface which can achieve abnormal reflection to reduce RCS and whose-10d B RCSR bandwidth is from 8.1 to 14.5 GHz,the RCSR principle of it lies in the backscattering cancellation,which depends on the phase difference of artificial magnetic conductor(AMC)units.The designed plasma-based checkerboard metasurface is a thin composite structure,including a checkerboard metasurface,a plasma layer,and an air gap which is between them.Full wave simulations confirm that the plasma-based checkerboard metasurface’s–10 dB RCS reduction bandwidth and RCS reduction amplitude,are both increased under different polarized waves compared with the only single plasma or the only metasurface.We also introduced the reason and mechanism of the interaction between plasma and the checkerboard metasurface to improve the RCSR effect in detail.As plasma-based checkerboard metasurface does not need the plasma to be too thick for plasma stealth,its application in practical scenarios is easier to implement.展开更多
The titanium oxide （TiO2） nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide （CdS） nanoparticles arc grown on top opened TiO2...The titanium oxide （TiO2） nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide （CdS） nanoparticles arc grown on top opened TiO2 nanotubes arrays by radio-frequency magnetron sputtering. X-ray diffraction, scanning electron mieroscopy, transmission electron microscopy and diffuse reflection spectra are used to study structural, morphological and optical properties of the CdS/TiO2 bilayer.展开更多
Background: Dialysis centres around the world use different concentrations of calcium in dialysate solution,ranging from 1. 25 to 1. 75 mmol / L. However,a dialysate concentration of 1. 25 mmol / L is recommended. [1]...Background: Dialysis centres around the world use different concentrations of calcium in dialysate solution,ranging from 1. 25 to 1. 75 mmol / L. However,a dialysate concentration of 1. 25 mmol / L is recommended. [1] Higher or lower dialysate calcium concentrations are indicated in patients,depending on their co-morbid factors. We explored the effects of using a calcium dialysate solution of 1. 50 mmol / L compared to a 1. 75 mmol / L calcium dialysate solution on the Blood Pressure (BP) ,serum concentrations of Calcium,Parathyroid Hormone (PTH) and Aldosterone in chronic hemodialysis (HD) patients. Method: 42 patients were enrolled in the study. First a 1. 50 mmol / L low calcium dialysate solution (LCDS) was used for 4 hour dialysis,and for the next session of HD,a 1. 75 mmol / L (NCDS) normal calcium dialysate solution was used. Blood pressure was measured at 5 intervals of time: pre HD,at 60,120,180 and 240 minutes into the HD session. Pre and post HD blood samples were taken for serum calcium,PTH and Aldosterone levels. Results: All 42 patients completed the study. With LCDS,the post HD serum calcium levels were (2. 51 ± 0. 14) mmol / L,compared to (2. 85 ± 0. 17) mmol / L for NCDS (P < 0. 01) . A post HD serum PTH level of (80. 6 ± 144. 93) pg / ml was observed when using LCDS,whereas a (52. 25 ± 115. 89) pg / ml serum PTH level was noted with NCDS (P < 0. 01) . As for aldosterone,a post HD value of (161. 77 ± 80. 42) ng / L was obtained with LCDS and (165. 50 ± 78. 84) ng / L with NCDS (P < 0. 01) . The mean post HD systolic blood pressure was (129. 17 ± 25. 42) mmHg with LCDS dialysis compared to (132. 50 ± 20. 32) mmHg for NCDS dialysis (P < 0. 01) and the diastolic BP values observed were (75. 10 ±10. 34) mmHg and (78. 26 ±11. 63) mm Hg(P <0. 01) ,respectively. Conclusion: LCDS can more effectively improve hypercalcemic status in dialysis patients than NCDS. Using LCDS stimulates the secretion of PTH more than when using NCDS. LCDS decreases aldosterone levels more than NCDS. Patients undergoing dialysis with LCDS have a lower post dialysis BP compared to those using NCDS. LCDS has a greater effect in decreasing both the post systolic and diastolic blood pressure than NCDS. Serum calcium,PTH and aldosterone levels have a greater decreasing effect on BP in LCDS than NCDS. Dialysate calcium profiling might be used as a means of therapy to control hypercalcemia, especially in patients who are hemodynamically stable.展开更多
The inner surface modification process by plasma-based low-energy ion implantation（PBLEII）with an electron cyclotron resonance（ECR）microwave plasma source located at the central axis of a cylindrical tube is model...The inner surface modification process by plasma-based low-energy ion implantation（PBLEII）with an electron cyclotron resonance（ECR）microwave plasma source located at the central axis of a cylindrical tube is modeled to optimize the low-energy ion implantation parameters for industrial applications.In this paper,a magnetized plasma diffusion fluid model has been established to describe the plasma nonuniformity caused by plasma diffusion under an axial magnetic field during the pulse-off time of low pulsed negative bias.Using this plasma density distribution as the initial condition,a sheath collisional fluid model is built up to describe the sheath evolution and ion implantation during the pulse-on time.The plasma nonuniformity at the end of the pulse-off time is more apparent along the radial direction compared with that in the axial direction due to the geometry of the linear plasma source in the center and the difference between perpendicular and parallel plasma diffusion coefficients with respect to the magnetic field.The normalized nitrogen plasma densities on the inner and outer surfaces of the tube are observed to be about 0.39 and 0.24,respectively,of which the value is 1 at the central plasma source.After a 5μs pulse-on time,in the area less than 2 cm from the end of the tube,the nitrogen ion implantation energy decreases from 1.5 keV to 1.3 keV and the ion implantation angle increases from several degrees to more than 40°;both variations reduce the nitrogen ion implantation depth.However,the nitrogen ion implantation dose peaks of about 2×10^（10）-7×10^（10）ions/cm^2 in this area are 2-4 times higher than that of 1.18×10^（10）ions/cm^2 and 1.63×10^（10）ions/cm^2 on the inner and outer surfaces of the tube.The sufficient ion implantation dose ensures an acceptable modification effect near the end of the tube under the low energy and large angle conditions for nitrogen ion implantation,because the modification effect is mainly determined by the ion implantation dose,just as the mass transfer process in PBLEII is dominated by low-energy ion implantation and thermal diffusion.Therefore,a comparatively uniform surface modification by the low-energy nitrogen ion implantation is achieved along the cylindrical tube on both the inner and outer surfaces.展开更多
文摘The use of cooled dialysate temperatures first came about in the early 1980s as a way to curb the incidence of intradialytic hypotension （IDH）. IDH was then, and it remains today, the most common complication affecting chronic hemodialysis patients. It decreases quality of life on dialysis and is an independent risk factor for mortality. Cooling dialysate was first employed as a technique to incite peripheral vasoconstriction on dialysis and in turn reduce the incidence of intradialytic hypotension. Although it has become a common practice amongst in-center hemodialysis units, cooled dialysate results in up to 70% of patients feeling cold while on dialysis and some even experience shivering. Over the years, various studies have been performed to evaluate the safety and effcacy of cooled dialysate in comparison to a standard, more thermoneutral dialysate temperature of 37℃. Although these studies are limited by small sample size, they are promising in many aspects. They demonstrated that cooled dialysis is safe and equally efficacious as thermoneutral dialysis. Although patients report feeling cold on dialysis, they also report increased energy and an improvement in their overall health following cooled dialysis. They established that cooling dialysate temperatures improves hemodynamic tolerability during and after hemodialysis, even in patients prone to IDH, and does so without adversely affecting dialysis adequacy. Cooled dialysis also reduces the incidence of IDH and has a protective effect over major organs including the heart and brain. Finally, it is an inexpensive measure that decreases economic burden by reducing necessary nursing intervention for issues that arise on hemodialysis such as IDH. Before cooled dialysate becomes standard of care for patients on chronic hemodialysis, larger studies with longer follow-up periods will need to take place to confrm the encouraging outcomes mentioned here.
文摘Dear Editor： There is accumulating evidence that human blood electronic circuit components and their application circuits become more and more important to cyborg implant/engineering, man-machine interface, hu- man disease detection and healing, and artificial brain evolutionusl. Here, we report the first development of human plasma-based amplifier circuit in the dis- crete as well as integrated circuit （IC） configuration mode. Electrolytes in the human blood contain an enormous number of charge carriers such as positive and negative molecule/atom ions, which are electri- cally conducting media and therefore can be utilized for developing electronic circuit components and their application circuits. These electronic circuits obvi- ously have very high application impact potential towards bio-medical engineering and medical science and technology.
文摘Glow discharge was utilized to add oxygen functional groups to the graphene platelets sample produced in chemical exfoliation synthesis. It was concluded based on Raman spectra that the graphene sample treated with the glow discharge preserves specific graphene features while no transformation to amorphous carbon is happening. SEM and EDS results indicated the increases of oxygen content in the graphene sample after the exposure to the glow discharge. Raman spectra also support the fact that the graphene platelets have been decorated with oxygen as the result of the glow discharge treatment.
基金supported by the Scientific Research Fund of Shaanxi Province (No.2001K10-G2-4) .
文摘Objective To study the solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate for hemodialysis in patients with high risk of bleeding. Methods Forty-two kidney failure patients with high risk of bleeding were divided into two groups (Group A and Group B) according to their hemodialysis manners. Patients in Group A were hemodialyzed with bicarbonate hemodialysate with low-molecular-weight heparin (dalteparin) anticoagulation and those in Group B with the new citrate anticoagulation hemodialysate prepared in our hospital without any other anticoagulant. Blood urea nitrogen (BUN) and creatinine (Cr) concentrations were measured before and after dialysis, and Kt/V and urea reduction rate (URR) were calculated. In addition, activated clotting time (ACT) and ionized calcium (iCa2+) concentration were also measured at the arterial and venous ends. Results ACT was extended and iCa2+ concentration decreased significantly at the venous end compared with those at the arterial end in Group B (P<0.01). BUN and Cr concentrations were markedly decreased after dialysis compared with those before dialysis in both groups (P<0.01), and no significant difference in solute clearance effect, as indicated by Kt/V and URR, was observed between Group A and Group B (P>0.05). Conclusion The solute clearance effect of the new concentrated anticoagulation hemodialysate of citrate is excellent during hemodialysis in kidney failure patients with high risk of bleeding.
文摘Objective：This study aims to investigate the effect of 4 different dialysate temperatures on blood pressure during hemodialysis for patients with hypertension.Methods：Using a self-controlled method,the patients＇ body temperature was set as T.Accordingly,the dialysate temperature was set as 37 ℃,T＋0.5 ℃,T,and T-0.5 ℃.The changes in blood pressure,heart rate,mean arterial pressure and dialysis-induced adverse reactions at the 4 different dialysate temperatures were consistently monitored.Results：Patients who received hemodialysis with 37 ℃ and T＋0.5 ℃ dialysate demonstrated an unstable blood pressure and a higher incidence of adverse reactions,Patients who received hemodialysis with T and T-0.5 ℃ dialysate showed a relatively stable blood pressure,heart rate,and mean arterial pressure during dialysis.In particular,dialysate at T-0.5 ℃ resulted in the most stable blood pressure,the fewest adverse reactions and the best self-assessed comfort scores（P 〈 0.01）.Conclusions：The dialysate temperature during hemodialysis for patients with hypertension should be set to a temperature based on patients＇ preoperative body temperate T or 0.5 ℃ below T.This practice is suggested to enhance the stability of patients＇ blood pressure and heart rate during hemodialysis,reduce complications and improve patients＇ tolerance of hemodialysis.
文摘<strong>Background.</strong> Intradialytic hypertension, a paradoxical rise in systolic blood pressure from pre- to postdialysis, is a poorly understood and difficult-to-treat phenomenon. We examined the effects of individually adjusted isonatremic and hyponatremic dialysate on intradialytic and interdialytic blood pressure in patients with intradialytic hypertension. <strong>Methods.</strong> We enrolled 11 patients with intradialytic hypertension in a prospective randomized cross-over study, with 4 treatment periods of different dialysate sodium concentrations. Period 1 (run-in) and 3 (wash-out) were standardized at 140 mEq/L;period 2 and 4 with iso- or hyponatremic sodium dialysate. Blood pressure was recorded each dialysis session, and 24-hour ambulatory blood pressure monitoring was performed at the end of each treatment period. <strong>Results.</strong> Isonatremic and hyponatremic dialysate were associated with significantly lower pre- and post-dialysis blood pressure as compared to baseline 140 mEq/L dialysate (predialysis 148.3 ± 24.7/67.7 ± 12.0 and 144.4 ± 16.5/68.8 ± 13.3 vs. 158.0 ± 18.3/75.6 ± 11.4 mmHg, resp p = 0.04 and 0.007 for systolic and p = 0.004 and 0.04 for diastolic blood pressure;postdialysis 154.2 ± 25.5/76.6 ± 14.1 and 142.5 ± 20.7/73.0 ± 12.9 vs. 159.1 ± 21.6/80.3 ± 12.1 mmHg, resp NS and p = 0.01 for systolic and NS and p = 0.04 for diastolic blood pressure). Postdialysis and 24 h systolic blood pressure tended to be lower with hyponatremic compared to isonatremic dialysate. <strong>Conclusion.</strong> Individually tailoring dialysate sodium concentration, based on the sodium set-point of each patient, resulted in a lower pre- and post-dialysis blood pressure in patients with intradialytic hypertension. 24 h blood pressure values tended to be lower as well with hyponatremic dialysate.
文摘For stealth technology,in order to overcome the limitations of thin-layer plasma for electromagnetic waves attenuation and further broaden the radar cross-section(RCS)reduction(RCSR)band of the metasurface,the plasma-based checkerboard metasurface composed of plasma and checkerboard metasurface is investigated to achieve better RCSR.We designed a checkerboard metasurface which can achieve abnormal reflection to reduce RCS and whose-10d B RCSR bandwidth is from 8.1 to 14.5 GHz,the RCSR principle of it lies in the backscattering cancellation,which depends on the phase difference of artificial magnetic conductor(AMC)units.The designed plasma-based checkerboard metasurface is a thin composite structure,including a checkerboard metasurface,a plasma layer,and an air gap which is between them.Full wave simulations confirm that the plasma-based checkerboard metasurface’s–10 dB RCS reduction bandwidth and RCS reduction amplitude,are both increased under different polarized waves compared with the only single plasma or the only metasurface.We also introduced the reason and mechanism of the interaction between plasma and the checkerboard metasurface to improve the RCSR effect in detail.As plasma-based checkerboard metasurface does not need the plasma to be too thick for plasma stealth,its application in practical scenarios is easier to implement.
文摘The titanium oxide （TiO2） nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide （CdS） nanoparticles arc grown on top opened TiO2 nanotubes arrays by radio-frequency magnetron sputtering. X-ray diffraction, scanning electron mieroscopy, transmission electron microscopy and diffuse reflection spectra are used to study structural, morphological and optical properties of the CdS/TiO2 bilayer.
文摘Background: Dialysis centres around the world use different concentrations of calcium in dialysate solution,ranging from 1. 25 to 1. 75 mmol / L. However,a dialysate concentration of 1. 25 mmol / L is recommended. [1] Higher or lower dialysate calcium concentrations are indicated in patients,depending on their co-morbid factors. We explored the effects of using a calcium dialysate solution of 1. 50 mmol / L compared to a 1. 75 mmol / L calcium dialysate solution on the Blood Pressure (BP) ,serum concentrations of Calcium,Parathyroid Hormone (PTH) and Aldosterone in chronic hemodialysis (HD) patients. Method: 42 patients were enrolled in the study. First a 1. 50 mmol / L low calcium dialysate solution (LCDS) was used for 4 hour dialysis,and for the next session of HD,a 1. 75 mmol / L (NCDS) normal calcium dialysate solution was used. Blood pressure was measured at 5 intervals of time: pre HD,at 60,120,180 and 240 minutes into the HD session. Pre and post HD blood samples were taken for serum calcium,PTH and Aldosterone levels. Results: All 42 patients completed the study. With LCDS,the post HD serum calcium levels were (2. 51 ± 0. 14) mmol / L,compared to (2. 85 ± 0. 17) mmol / L for NCDS (P < 0. 01) . A post HD serum PTH level of (80. 6 ± 144. 93) pg / ml was observed when using LCDS,whereas a (52. 25 ± 115. 89) pg / ml serum PTH level was noted with NCDS (P < 0. 01) . As for aldosterone,a post HD value of (161. 77 ± 80. 42) ng / L was obtained with LCDS and (165. 50 ± 78. 84) ng / L with NCDS (P < 0. 01) . The mean post HD systolic blood pressure was (129. 17 ± 25. 42) mmHg with LCDS dialysis compared to (132. 50 ± 20. 32) mmHg for NCDS dialysis (P < 0. 01) and the diastolic BP values observed were (75. 10 ±10. 34) mmHg and (78. 26 ±11. 63) mm Hg(P <0. 01) ,respectively. Conclusion: LCDS can more effectively improve hypercalcemic status in dialysis patients than NCDS. Using LCDS stimulates the secretion of PTH more than when using NCDS. LCDS decreases aldosterone levels more than NCDS. Patients undergoing dialysis with LCDS have a lower post dialysis BP compared to those using NCDS. LCDS has a greater effect in decreasing both the post systolic and diastolic blood pressure than NCDS. Serum calcium,PTH and aldosterone levels have a greater decreasing effect on BP in LCDS than NCDS. Dialysate calcium profiling might be used as a means of therapy to control hypercalcemia, especially in patients who are hemodynamically stable.
基金supported by National Natural Science Foundation of China(Nos.50725519,51271048,51321004)
文摘The inner surface modification process by plasma-based low-energy ion implantation（PBLEII）with an electron cyclotron resonance（ECR）microwave plasma source located at the central axis of a cylindrical tube is modeled to optimize the low-energy ion implantation parameters for industrial applications.In this paper,a magnetized plasma diffusion fluid model has been established to describe the plasma nonuniformity caused by plasma diffusion under an axial magnetic field during the pulse-off time of low pulsed negative bias.Using this plasma density distribution as the initial condition,a sheath collisional fluid model is built up to describe the sheath evolution and ion implantation during the pulse-on time.The plasma nonuniformity at the end of the pulse-off time is more apparent along the radial direction compared with that in the axial direction due to the geometry of the linear plasma source in the center and the difference between perpendicular and parallel plasma diffusion coefficients with respect to the magnetic field.The normalized nitrogen plasma densities on the inner and outer surfaces of the tube are observed to be about 0.39 and 0.24,respectively,of which the value is 1 at the central plasma source.After a 5μs pulse-on time,in the area less than 2 cm from the end of the tube,the nitrogen ion implantation energy decreases from 1.5 keV to 1.3 keV and the ion implantation angle increases from several degrees to more than 40°;both variations reduce the nitrogen ion implantation depth.However,the nitrogen ion implantation dose peaks of about 2×10^（10）-7×10^（10）ions/cm^2 in this area are 2-4 times higher than that of 1.18×10^（10）ions/cm^2 and 1.63×10^（10）ions/cm^2 on the inner and outer surfaces of the tube.The sufficient ion implantation dose ensures an acceptable modification effect near the end of the tube under the low energy and large angle conditions for nitrogen ion implantation,because the modification effect is mainly determined by the ion implantation dose,just as the mass transfer process in PBLEII is dominated by low-energy ion implantation and thermal diffusion.Therefore,a comparatively uniform surface modification by the low-energy nitrogen ion implantation is achieved along the cylindrical tube on both the inner and outer surfaces.
