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Expression and Purification of Hydrophilic Domains of Bovine Anion Exchanger,Member 1 and Electrogenic Sodium Bicarbonate Cotransporter 1
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作者 TIAN Wei YU Duo-wei 《Animal Husbandry and Feed Science》 CAS 2009年第8期10-13,共4页
[ Objective] To express and purify the intracellular hydrophilic domains of bovine membrane carrier proteins:anion exchanger, member 1 (AE1) and electregenic sodium bicarbonate cotransporter 1 (NBCel), which were... [ Objective] To express and purify the intracellular hydrophilic domains of bovine membrane carrier proteins:anion exchanger, member 1 (AE1) and electregenic sodium bicarbonate cotransporter 1 (NBCel), which were associated with bicarbonate ion transport. [ Method] The hydrophilic domains of bovine AE1 and NBCel were amplified by PCR and inserted into the prokaryotic expression vector pET-28a, respectively. The recombinant plasmids were transformed into the expression strain E. coli BL21 (DE3) and then induced by IPTG. The expressed proteins were purified by nickel ion affinity chromatography and analyzed by 15% SDS-PAGE. [Result] The hydrophilic domains of bovine AE1 and NBCel were amplified respectively by PCR and expressed by prokaryotic expression system with the induction of IPTG. They were mainly expressed in the cyto- plasm of E. coli and high-purity was achieved by nickel ion affinity chromatography. [Condusion] The expression of the hydrophilic domains of bovine AE1 and NBCel provides a major exit route for preparation of antibodies and the regulatory mechanisms of carrier proteins. 展开更多
关键词 Anion exchanger Member 1 Electregenic sodium bicarbonate cotransporter 1 Cloning Expression Purification
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Velocity Form Calculations of Generalized Oscillator Strengths for 3s→ (3p, 4p, 5p, 6p) Dipole Transitions of Atomic Sodium in Debye Plasma
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作者 Louis Gomis Clement Diatta +4 位作者 Moustapha Sadibou Tall Ibrahima Gueye Faye Rama Gomis Yande Diouf Mamadou Coulibaly 《Open Journal of Applied Sciences》 2024年第6期1512-1529,共18页
In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in Debye plasma, were calculated by using wavefunctions which we... In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in Debye plasma, were calculated by using wavefunctions which were obtained numerically from the restricted Hartree-Fock (RHF) equation. This RHF equation employs the local density approach for exchange interactions including plasma Debye screening. Theoretical RHF and random phase approximation with exchange (RPAE) velocity calculations have shown that the GOSs for excitations to 3 s0(3 p,4 p,5 p,6 p)depend on the plasma Debye screening effects, as shown by the reduction in the GOS amplitude with decreasing Debye length λD. The agreement between the present RPAE V results for the transitions 3 s→3 s0(3 p,4 p,5 p)and the length calculations of Martínez-Flores was satisfactory. Correlation effects were found quite to be significant in the vicinity of the maxima of the GOS of the 3 s→3 s0(4 p,5 p,6 p)excitations by using the RPAE V approach. We note the poor influence of many electron correlations on the GOS of (3 s→3 p)transition with the same principal quantum number. Finally, we comment that the RPAE V calculations are useful in investigating electron correlation effects on the transition GOS of atomic sodium planted in Debye plasma. The present velocity results also reveal that the 3 s→3 s0(5p, 6p)transition GOSs tend to be delocalized due to more significant screening effects at Debye lengths λD=20and 30 a.u. for excited subshells 5p and 6p, respectively. We report here novel results of GOS for 3 s→3 s06ptransition obtained from different Debye lengths. 展开更多
关键词 Plasma Screening Effect Correlation Effect sodium Atomic Velocity Form GOS Restricted Hatree-Fock Random Phase Approximation with exchange
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Resuscitation from Prolonged Ventricular Fibrillation by Epinephrine Combined with Sodium-Hydrogen Exchanger Isoform-1 Inhibitor Cariporide
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作者 易忠 《South China Journal of Cardiology》 CAS 2002年第1期30-34,共5页
Objective To test the resuscitative effects from prolonged ventricular fibrillation by epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide. Methods 16 rats were received a 3 mg/kg bolu... Objective To test the resuscitative effects from prolonged ventricular fibrillation by epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide. Methods 16 rats were received a 3 mg/kg bolus of Cariporide or the same volume of 0.9%NaCl solution (control) 15 seconds before completion 12 minutes untreated VF. Chest compression (CC) was started for a total of 8 minutes. Adjusted the depth of compressor so that the aortic diastolic pressure to 25~28 mmHg during the 2nd minute of CC. Fix the depth of the piston and this depth was used throughout the remaining 6 minutes of CC. 10 seconds before starting the 3rd minute of chest compression, injected epinephrine (30 μg/kg). Recorded the time at which restoration of spontaneous circulation (ROSC) occurred in Cariporide treated rats. Electrical defibrillation was timed in control group to match the time of spontaneous defibrillation in Cariporide treated rats. To the rats, which cant be defibrillated spontaneously, received chest compression and rescues electrical shocks. Results compared with control group, with the same CC depth, Cariporide treated rats received the higher and longer lasting coronary perfusion pressure (P< 0.05), higher resuscitative rate (P< 0.05), less post resuscitative ventricular ectopic activities (P< 0.001), better hemodynamic effects and longer survival time (P< 0.05). Conclusion Epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide may represent a novel and remarkably effective intervention for resuscitation from prolonged VF. 展开更多
关键词 Cardiopulmonary resuscitation Prolonged ventricular fibrillation Epinephrine sodium hydrogen exchanger isoform 1 inhibitor Coronary perfusion pressure
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Exchange Reaction Characteristics of Anion Exchange Resin for Diclofenac Sodium
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作者 吴静 杨丽 +3 位作者 刘宏飞 王超 曹国良 潘卫三 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期228-232,共5页
Aim To study the exchange reaction characteristics of anion exchange resin for diclofenac sodium. Methods The drug-resin complexes were prepared by a batch method with diclofenac sodium as the model drug and the stron... Aim To study the exchange reaction characteristics of anion exchange resin for diclofenac sodium. Methods The drug-resin complexes were prepared by a batch method with diclofenac sodium as the model drug and the strong anion exchange resin (201 × 7) as the carrier. The effects of different forms (OH~ - and Cl~ - ) of the strong anion exchange resin, the particle size of the resin, and the reaction temperature on the exchange behavior were described. The exchange kinetic profiles were fitted. The related exc... 展开更多
关键词 diclofenac sodium anion exchange resin exchange kinetics exchange thermodynamics
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Roles of Na^+/Ca^(2+) exchanger 1 in digestive system physiology and pathophysiology 被引量:3
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作者 Qiu-Shi Liao Qian Du +2 位作者 Jun Lou Jing-Yu Xu Rui Xie 《World Journal of Gastroenterology》 SCIE CAS 2019年第3期287-298,共12页
The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX fami... The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption.This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments. 展开更多
关键词 Na^+/Ca^2+exchanger DIGESTIVE system diseases Ion channel sodium Calcium
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Effect of Compounding of Sodium Tripolyphosphate and Super Plasticizers on the Hydration of α-calcium Sulfate Hemihydrate 被引量:3
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作者 潘伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期737-744,共8页
The inhibition and its mechanism of sodium tripolyphosphate (STP) composited with super plasticizers (SPs) on hydration of α-calcium sulfate hemihydrate were studied by setting time, strength, hydration heat, X-r... The inhibition and its mechanism of sodium tripolyphosphate (STP) composited with super plasticizers (SPs) on hydration of α-calcium sulfate hemihydrate were studied by setting time, strength, hydration heat, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electronic probe micro analysis (EPMA), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC) measurements. The experimental results show that compared with STP addition, compositing STP with polycarboxylate (PC) plasticizer, the final setting time is prolonged from 0.5h to 2hs. While formulating STP with naphthalene-based plasticizer (NAP) or sulfonate melamine formaldehyde plasticizer (SMF), the final setting time is reduced to quarter of an hour. Similar changes can also be found in the rate of exothermic hydration and hydration degree. Formulating STP with suitable addition of PC can enhance the strength, while compositing STP and NAP or SMF weakens the strength. Besides, adding STP or STP and SMF, obvious movement (more than 1ev) of binding energy of Ca2p1/2 and Ca2p3/2 is detected. Compared with STP addition, content of the characteristic element (P) of STP is cut down form 1.1% to 0.49% by compositing STP with SMF. Furthermore, as hydration age increases, hydration inhibition in the presence of admixtures weakens and even disappears within 56 h. 展开更多
关键词 α-calcium sulfate hemihydrate HYDRATION sodium tripolyphosphate PLASTICIZER ADSORPTION
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Comparison and Evaluation of Two Analytical Methods for Cation Exchange Capacity and Exchangeable Sodium Percentage of Five Soil Types in Central Sudan 被引量:3
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作者 Jamal Elfaki Mohamed Gafer +1 位作者 Magboul Sulieman Mushtaha Ali 《Open Journal of Soil Science》 2015年第12期311-318,共8页
Twenty-six soil samples were collected from five soil profiles at different climatological and ecological regions in central Sudan. Soil profile was dug in each studied area and morphological profile description was c... Twenty-six soil samples were collected from five soil profiles at different climatological and ecological regions in central Sudan. Soil profile was dug in each studied area and morphological profile description was carried out for different horizons. All samples were analyzed using two different methods to determine Cation Exchange Capacity (CEC) and exchangeable sodium percentage (ESP). Statistical analysis (T-test) was used in order to investigate the differences between soil samples for the studied locations. Significant differences appeared when compared the two methods for CEC determination at Gedaref area, Wad Medani and Nile flood plain and that appeared in evaluation of ESP at Nile flood plain and Shambat area. The results also revealed that, the developed method used in this study was more practical, simple and reliable for determination of CEC and ESP as the currently used in most soil laboratories. In addition, it will be safer than the other methods in some problematic soils. The adoption of this developed method is advisable because it is less time consuming as it omits the washing step. In contrast, the old method cannot be a good substitute in laboratories which have no possibility to determine sodium by using flame photometer. We conclude that when the developed method is used to determine CEC and ESP time will be saved, that fewer amounts of chemicals will be used and that accurate results will be achieved. 展开更多
关键词 ECOLOGICAL REGIONS CENTRAL SUDAN CATION exchange Capacity exchangeable sodium PERCENTAGE
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Sodium-Zinc Exchange Selectivity on Wyoming Montmorillonite in Different Background Anion Solutions
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作者 YOUYOUWEN G.F.VAXCE 《Pedosphere》 SCIE CAS CSCD 2002年第4期289-299,共11页
The effect of background anion on cation exchange reactions, suchas Na-Ca and Na-Cu exchange reac- tions, on montmorillonites has beenstudied, but the results are not always clear and discrepancies existin the literat... The effect of background anion on cation exchange reactions, suchas Na-Ca and Na-Cu exchange reac- tions, on montmorillonites has beenstudied, but the results are not always clear and discrepancies existin the literature. In this study, the exchange of zinc (Zn^2+) forsodium (Na^+) on Wyoming montmorillonite was investigated at 298 deg.K using Cl^-, ClO_4^-, NO_3^-, Oac^-, and SO_4~2- solution media at aconstant total metal charge concentration of 0.02000 mol_c L^-1.Results indicated that the clay CEC values were essential similar forCl^-, ClO_4^-, NO_3^- and SO_4~2- solution media with an average CECof 0.856±0.008 mol_c kg^-1; in an OAc^- solution the clay CEC wasmuch higher than that in other anion media. 展开更多
关键词 anion background cation exchange MONTMORILLONITE sodium ZINC
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Inhibition of the Na<sup>+</sup>/Ca<sup>2+</sup>Exchanger NCX<sub>1</sub>Expressed in <i>Xenopus</i>Oocyte by Glycyrrhizic Acid and Cyclophylin A
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作者 Jan Laudenbach Yu Wang +4 位作者 Beibei Xing Silvia Schwarz Yinfang Xu Quanbao Gu Wolfgang Schwarz 《Journal of Biosciences and Medicines》 2017年第3期128-141,共14页
The Na+/Ca2+ exchanger plays an important role in regulation of airway smooth muscle contraction by regulating intracellular calcium, and is a potential target for treatment of asthma. To test modulation of exchanger ... The Na+/Ca2+ exchanger plays an important role in regulation of airway smooth muscle contraction by regulating intracellular calcium, and is a potential target for treatment of asthma. To test modulation of exchanger activity, we used Xenopus oocytes as model system. Na+/Ca2+ exchanger was expressed in the cells by microinjection of cRNA of the exchanger isoform NCX1. The activity of NCX1 was determined as Ni2+-sensitive current under voltage clamp in low Cl– medium and in the presence of the Cl–-channel inhibitor niflumic acid. Only this composition of solution allowed determining NCX1-mediated current with sufficient accuracy. Among a few tested Chinese herbal drugs, glycyrrhizic acid turned out to be a potent inhibitor of NCX1 with an apparent IC50 value of 40 μM. Previous work had revealed elevated cyclophylin A concentration in serum of asthmatic rats after receiving acupuncture treatment. Extracellular incubation of the oocytes in cyclophylin A for one day led to significant inhibition with an apparent IC50 value of about 1 μM. We suggest that effects of acupuncture and application of glycyrrhizic acid as an active constituent of Chinese medicine for treatment of asthma symptoms may partially be attributed to inhibition of the reversed mode of NCX1 and that these compounds may stimulate the search for new anti-asthmatic drugs. 展开更多
关键词 sodium-calcium exchanger Asthma Voltage Clamp Glycyrrhizic Acid Cyclophylin A
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维生素B_(6)对动脉粥样硬化小鼠血管内皮损伤的影响及作用机制
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作者 朱茉莉 李怡霏 +5 位作者 李珍珍 赵海燕 刘艳华 邱月 万光瑞 李鹏 《新乡医学院学报》 CAS 2024年第1期1-7,共7页
目的探讨维生素B_(6)(VB_(6))对动脉粥样硬化(AS)小鼠血管内皮损伤的影响及作用机制。方法将36只ApoE-/-小鼠随机分为对照组、AS组、VB_(6)组、AS+LiCl组、AS+VB_(6)组和AS+VB_(6)+LiCl组,每组6只。AS组、AS+LiCl组、AS+VB_(6)组和AS+VB... 目的探讨维生素B_(6)(VB_(6))对动脉粥样硬化(AS)小鼠血管内皮损伤的影响及作用机制。方法将36只ApoE-/-小鼠随机分为对照组、AS组、VB_(6)组、AS+LiCl组、AS+VB_(6)组和AS+VB_(6)+LiCl组,每组6只。AS组、AS+LiCl组、AS+VB_(6)组和AS+VB_(6)+LiCl组小鼠高脂饮食12周建立AS模型;对照组和VB_(6)组小鼠常规饮食、正常饮水12周。12周后,对照组小鼠常规饮食,每日给予和VB_(6)组等体积的生理盐水灌胃;VB_(6)组小鼠常规饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1));AS+LiCl组小鼠继续给予高脂饮食,每日灌胃给予LiCl(1 mg·kg^(-1));AS+VB_(6)组小鼠继续给予高脂饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1));AS+VB_(6)+LiCl组小鼠继续给予高脂饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1))和LiCl(1 mg·kg^(-1));6组小鼠均干预4周。干预结束后,采用酶联免疫吸附试验检测各组小鼠血清中一氧化氮(NO)、丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性。苏木精-伊红染色观察各组小鼠胸主动脉组织形态,并计算AS斑块面积占血管总面积的百分比。离体血管环实验检测胸主动脉舒张率。免疫组织化学法检测胸主动脉中钠氢交换蛋白1(NHE1)表达。结果与对照组相比,AS组小鼠血清中NO水平和SOD活性显著下降,MDA水平显著升高(P<0.05);VB_(6)组与对照组小鼠血清中NO、MDA水平和SOD活性比较差异无统计学意义(P>0.05)。与AS组相比,AS+VB_(6)组小鼠血清中NO水平和SOD活性显著上升,MDA水平显著下降(P<0.05);AS+LiCl组、AS+VB_(6)+LiCl组与AS组小鼠血清中NO、MDA水平和SOD活性比较差异无统计学意义(P>0.05)。与AS+VB_(6)组相比,AS+VB_(6)+LiCl组小鼠血清中NO水平和SOD活性显著下降,MDA水平显著升高(P<0.05)。AS组小鼠AS斑块面积占血管总面积的百分比显著高于对照组(P<0.05);VB_(6)组与对照组小鼠AS斑块面积占血管总面积的百分比比较差异无统计学意义(P<0.05)。AS+VB_(6)组小鼠斑块面积占血管总面积的百分比显著低于AS组(P<0.05);AS+LiCl组、AS+VB_(6)+LiCl组与AS组小鼠AS斑块面积占血管总面积的百分比比较差异无统计学意义(P<0.05)。AS+VB_(6)+LiCl组小鼠AS斑块面积占血管总面积的百分比显著高于AS+VB_(6)组(P<0.05)。对照组小鼠血管内皮光滑平整,细胞排列整齐有序;AS组、AS+LiCl组和AS+VB_(6)+LiCl组小鼠的血管组织结构紊乱、血管内皮粗糙;VB_(6)组和AS+VB_(6)组小鼠的血管壁结构正常、血管内皮光滑、细胞排列有序。AS组小鼠乙酰胆碱(Ach)诱导的胸主动脉舒张率显著低于对照组(P<0.05);VB_(6)组与对照组小鼠Ach诱导的胸主动脉舒张率比较差异无统计学意义(P>0.05)。AS+VB_(6)组小鼠Ach诱导的胸主动脉舒张率显著低于AS组(P<0.05);AS+LiCl组、AS+VB_(6)+LiCl组与AS组小鼠Ach诱导的胸主动脉舒张率比较差异无统计学意义(P>0.05)。AS+VB_(6)+LiCl组小鼠Ach诱导的胸主动脉舒张率显著高于AS+VB_(6)组(P<0.05)。6组小鼠硝普钠诱导的胸主动脉舒张率比较差异均无统计学意义(P>0.05)。AS组小鼠胸主动脉中NHE1蛋白表达量百分比显著高于对照组(P<0.05);VB_(6)组与对照组小鼠胸主动脉中NHE1蛋白表达量百分比比较差异无统计学意义(P>0.05)。AS+VB_(6)组小鼠胸主动脉中NHE1蛋白表达量百分比显著低于AS组(P<0.05);AS+LiCl组、AS+VB_(6)+LiCl组与AS组小鼠胸主动脉中NHE1蛋白表达量百分比比较差异无统计学意义(P>0.05)。AS+VB_(6)+LiCl组小鼠胸主动脉中NHE1蛋白表达量百分比显著高于AS+VB_(6)组(P<0.05)。结论VB_(6)可通过抑制NHE1蛋白的表达来改善AS小鼠的血管内皮损伤。 展开更多
关键词 维生素B_(6) 钠氢交换蛋白1 内皮损伤 动脉粥样硬化 氧化应激
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改良的电感耦合等离子体发射光谱(ICP-OES)法测定石灰性土壤中交换性盐基钙、镁、钠、钾
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作者 张雅静 卢禹含 +2 位作者 聂喜涛 张佳楠 张宇婷 《世界地质》 CAS 2024年第4期600-607,共8页
为提升石灰性土壤中交换性盐基钙、镁、钠、钾的分析效率与精确度,笔者采用电感耦合等离子体发射光谱(ICP-OES)技术测定其含量。结果表明,最优条件为用70%乙醇溶液反复淋洗样品,再用pH值为8.5的0.1 mol/L的氯化铵-70%乙醇溶液进行交换处... 为提升石灰性土壤中交换性盐基钙、镁、钠、钾的分析效率与精确度,笔者采用电感耦合等离子体发射光谱(ICP-OES)技术测定其含量。结果表明,最优条件为用70%乙醇溶液反复淋洗样品,再用pH值为8.5的0.1 mol/L的氯化铵-70%乙醇溶液进行交换处理,蒸干后加入10mL 20%~30%的硝酸溶液进行酸化处理。经此处理,把传统的单标溶液转变为混标配置,选择谱线分别为钙317.933 nm、镁279.553 nm、钠589.592 nm、钾766.491 nm,测得国标样品的加标回收率为98.0%~100.7%,检出限分别为0.008、0.005、0.004、0.007 mg/L。对两个国标样品GBW(E)070337、GBW(E)070341进行验证,测得的相对标准偏差(RSD)为0.29%~0.98%(n=5)。对吉林土壤(样品1)测得的结果与火焰光度计+原子吸收分光光度法测得的结果无显著性差异。结果表明该方法适用于石灰性土壤交换性盐基钙、镁、钠、钾的分析。 展开更多
关键词 电感耦合等离子体发射光谱法 石灰性土壤 交换性钙、镁、钠、钾
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长期施用有机肥对松嫩平原盐碱土壤盐碱性质和化学计量比的影响 被引量:1
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作者 翟车宇 骆静梅 +2 位作者 刘昌杰 张娟 孟庆峰 《中国农业科技导报》 CAS CSCD 北大核心 2024年第2期153-161,共9页
盐碱土盐碱化程度高、养分有效性低,施加有机肥可以促进土壤盐分淋洗,降低土壤盐碱化程度,增加养分含量和土壤碳、氮、磷的供应能力。根据土壤施加腐熟牛粪的年限,设置施加腐熟牛粪21(Y21)、18(Y18)、15年(Y15)和未施加腐熟牛粪(CK)共4... 盐碱土盐碱化程度高、养分有效性低,施加有机肥可以促进土壤盐分淋洗,降低土壤盐碱化程度,增加养分含量和土壤碳、氮、磷的供应能力。根据土壤施加腐熟牛粪的年限,设置施加腐熟牛粪21(Y21)、18(Y18)、15年(Y15)和未施加腐熟牛粪(CK)共4个处理,采集各处理0—20和20—40 cm土层的土壤样品,分析土壤盐碱性质和养分含量。结果表明,0—20和20—40 cm土层Y21、Y18、Y15处理有机碳(soil organic carbon,SOC)、全氮(total-N,TN)和全磷(total-P,TP)含量显著高于CK;土壤水溶性盐离子、pH、电导率(electrical conductance,EC)、钠吸附比(sodium adsorption ratio,SAR)和碱化度(exchangeable sodium percentage,ESP)较CK显著降低。在0—20和20—40 cm土层,Y21、Y18、Y15处理碳氮比(C/N)较CK显著降低;与CK相比,Y21与Y15处理0—20 cm土层氮磷比(N/P)由0.95显著增加至1.84和2.11,20—40 cm土层N/P由1.15显著增加至2.25和2.44;土壤碳磷比(C/P)在0—20 cm土层规律不明显,在20—40 cm土层Y21、Y18、Y15处理与CK相比差异不显著。多元线性回归模型显示,C/N受SOC、TN和ESP影响,N/P和C/P主要受TP和TN影响。综上所述,松嫩平原西部草甸碱土施加有机肥后土壤盐碱程度降低,SOC、TN、TP含量和N/P增加,C/N降低,且施加有机肥改良15年的土壤供碳、供氮潜力达到最大。 展开更多
关键词 草甸碱土 腐熟牛粪 碱化度 生态化学计量比
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脱硫石膏改良盐碱土壤综合效果评价研究 被引量:2
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作者 姜展博 宁松瑞 王全九 《土壤学报》 CAS CSCD 北大核心 2024年第3期699-713,共15页
为探究区域脱硫石膏改良盐碱土壤的综合效果,通过文献调研统计分析了施加量在0~60 t·hm^(–2)范围内的脱硫石膏,对土壤pH、交换性钠百分率、浸提液电导率和作物产量的变化特征。基于灰色关联分析法和熵权法建立了以脱硫石膏施加量... 为探究区域脱硫石膏改良盐碱土壤的综合效果,通过文献调研统计分析了施加量在0~60 t·hm^(–2)范围内的脱硫石膏,对土壤pH、交换性钠百分率、浸提液电导率和作物产量的变化特征。基于灰色关联分析法和熵权法建立了以脱硫石膏施加量为自变量的盐碱土壤综合改良评价模型。结果表明:施用脱硫石膏可降低土壤pH和交换性钠百分率,提高作物产量(油葵、苜蓿、玉米、水稻、小麦、枸杞和甜高粱),但增加了土壤浸提液的电导率值。随着脱硫石膏施加量的增加,土壤pH和交换性钠百分率的降低率及作物产量的增加率呈先增加后减少的趋势,而土壤浸提液电导率的增加率呈增加的趋势。在中度或重度盐碱土壤为获得作物高产,脱硫石膏施加量不宜超过30 t·hm^(–2)。为综合分析脱硫石膏改良盐碱土壤的效果,本文基于熵权—灰色关联度评价模型,分析脱硫石膏最佳施加量。轻、中度盐碱土施加18~22 t·hm^(–2)的脱硫石膏;重度盐碱土施加23~29 t·hm^(–2)的脱硫石膏可取得良好的改土增产效果。研究成果为脱硫石膏改良盐碱土壤提供参考依据。 展开更多
关键词 土壤改良 作物产量 pH 交换性钠百分率 土壤电导率
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局部枸橼酸钠抗凝在单重血浆置换中的应用及安全性分析
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作者 高良云 朱星瑜 +3 位作者 王悦琳 金飞英 胡日红 姚国明 《浙江临床医学》 2024年第4期544-546,共3页
目的探讨局部4%枸橼酸钠注射液在单重血浆置换抗凝中的应用,并评估该方法的安全性。方法回顾性分析2015年1月至2022年6月单重血浆置换的患者52例,根据抗凝方式分为枸橼酸组和低分子肝素组,共进行血浆置换144次。枸橼酸组抗凝方案:4%枸... 目的探讨局部4%枸橼酸钠注射液在单重血浆置换抗凝中的应用,并评估该方法的安全性。方法回顾性分析2015年1月至2022年6月单重血浆置换的患者52例,根据抗凝方式分为枸橼酸组和低分子肝素组,共进行血浆置换144次。枸橼酸组抗凝方案:4%枸橼酸从膜型血浆分离器前输注,根据置换液成分进行调整,置换血浆时,枸橼酸钠流量为120 mL/h;置换白蛋白稀释液、林格注射液时,枸橼酸流量调整为140 mL/h。5%葡萄糖酸钙采用微泵外周静脉输注,根据输注总量和血浆置换时间全程匀速输注。低分子肝素组抗凝方案:根据患者体质量,在治疗前20~30 min一次性静脉注射60~80 IU/kg,治疗期间不另追加。观察两组患者行血浆置换治疗时抗凝效果及不良反应发生情况。结果枸橼酸组共进行血浆置换44次,未发生抗凝失败;低分子肝素组共进行血浆置换100次,发生5次抗凝失败,两组患者未发生明显出血、低钙血症、肌肉痉挛等并发症。枸橼酸组发生滤器血凝级别2~3级、动脉壶血凝块、静脉壶血凝块比例低于低分子肝素组(P<0.05)。枸橼酸抗凝前后比较,离子钙变化差异有统计学意义(P=0.002)。结论局部枸橼酸钠抗凝方案在血浆置换治疗中简单易行,相对传统低分子肝素,其抗凝效果更加理想、应用范围更广,且安全有效。 展开更多
关键词 血浆置换 枸橼酸钠 低钙血症
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乙醇和氯化铵提取-原子吸收光谱法测定石灰性土壤中的交换性钾、钠、钙、镁
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作者 席秀丽 高艳敏 +1 位作者 王生进 刘春虎 《化学分析计量》 CAS 2024年第1期58-64,共7页
建立乙醇和氯化铵提取-原子吸收分光光度法测定石灰性土壤中的交换性钾、钠、钙、镁。采用乙醇和氯化铵对石灰性土壤进行处理,以离心分离的方式对石灰性土壤中易溶的氯化物和硫酸盐进行清洗及交换性钾、钠、钙、镁离子的提取,提取液以... 建立乙醇和氯化铵提取-原子吸收分光光度法测定石灰性土壤中的交换性钾、钠、钙、镁。采用乙醇和氯化铵对石灰性土壤进行处理,以离心分离的方式对石灰性土壤中易溶的氯化物和硫酸盐进行清洗及交换性钾、钠、钙、镁离子的提取,提取液以原子吸收分光光度计测定。交换液pH为8.5,乙醇体积分数为70%,氯化铵浓度为0.1 mol/L。交换性盐基钾、钠、钙、镁的质量浓度分别在0~10、0~2.5、0~40、0~5.0 mg/L范围内与吸光度线性关系良好,相关系数均大于0.9990,方法检出限分别为0.06、0.10、0.21、0.04 mmol/kg。样品加标回收率为97.0%~104%,测定结果的相对标准偏差为2.81%~5.85%(n=6)。采用所建方法对土壤有效态成分分析标准物质GBW(E)070336进行测定,测定结果的相对误差为0.40%~6.67%。该方法快速,适用于石灰性土壤中交换性钾、钠、钙、镁的测定。 展开更多
关键词 石灰性土壤 乙醇 氯化铵 交换性钾 交换性钠 交换性钙 交换性镁 原子吸收光谱法
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禽白血病病毒J亚群感染鸡组织中细胞受体chNHE 1的表达分析
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作者 张莉 于蒙蒙 +7 位作者 王颖 王素艳 许壮壮 刘鹏 陈运通 祁小乐 李留安 高玉龙 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第8期3631-3639,共9页
旨在研究鸡钠氢交换蛋白1(chicken sodium hydrogen exchanger isoform 1,chNHE1)在不同类型鸡组织内的表达情况,J亚群禽白血病病毒(subgroup J avian leukosis virus, ALV-J)的组织嗜性及ALV-J感染后组织chNHE1的mRNA变化情况。本研究... 旨在研究鸡钠氢交换蛋白1(chicken sodium hydrogen exchanger isoform 1,chNHE1)在不同类型鸡组织内的表达情况,J亚群禽白血病病毒(subgroup J avian leukosis virus, ALV-J)的组织嗜性及ALV-J感染后组织chNHE1的mRNA变化情况。本研究利用qPCR技术,检测了商品肉鸡、商品蛋鸡和SPF鸡脏器内的chNHE1转录量,ALV-J感染鸡后各组织的病毒载量及组织chNHE1的转录量的变化。结果显示,chNHE1在3种类型鸡的心、肝、脾、肺、肾、盲肠扁桃体、胸腺和法氏囊中均能检测到,但转录量高低存在较大差异,其中,免疫器官内的chNHE1转录量相对较高;SPF鸡接种ALV-J后,心、脾、肾和盲肠扁桃体中的病毒载量相对较高,而肝、肺、胸腺和法氏囊中的病毒载量相对较低;ALV-J感染后,脾、肾和盲肠扁桃体中的chNHE1转录量明显上调,但心中的转录量与空白对照相比无明显变化。本研究分析了3种类型鸡chNHE1的组织转录特点及ALV-J感染对组织内chNHE1转录的影响,该研究结果为探究受体chNHE1的转录与ALV-J的组织嗜性的关系提供重要的理论依据。 展开更多
关键词 J亚群禽白血病病毒 鸡钠氢交换蛋白1 组织表达 转录量变化
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肾近端小管钠氢交换因子3在血管紧张素Ⅱ依赖性高血压中的作用机制研究进展
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作者 李晓春 卓家隆 +3 位作者 郑晓文 赵春菱 张剑锋 姜岳明 《广西医科大学学报》 CAS 2024年第11期1507-1512,共6页
高血压是一种涉及遗传易感性、神经内分泌失调、心血管和肾功能障碍以及饮食因素的多因素疾病。对人正常血压稳态和高血压发展的贡献因素或机制中,焦点集中在钠(Na^(+))摄入量和盐敏感性。临床、流行病学和遗传动物模型的研究显示,Na^(+... 高血压是一种涉及遗传易感性、神经内分泌失调、心血管和肾功能障碍以及饮食因素的多因素疾病。对人正常血压稳态和高血压发展的贡献因素或机制中,焦点集中在钠(Na^(+))摄入量和盐敏感性。临床、流行病学和遗传动物模型的研究显示,Na^(+)摄入量与血压稳态密切相关,而过量的Na^(+)摄入在黑人、老年人和患有慢性肾病的人群中与血压升高关系较为密切。Na^(+)摄入和排泄的平衡由胃肠道小肠和肾近端和远端小管来协调。Na^(+)氢(H^(+))交换因子3(NHE3),即溶质载体家族9成员3(SLC9A3),在小肠和肾脏的近端小管中介导主动的跨细胞钠和碳酸氢盐的重吸收发挥了关键作用。然而,小肠和肾近端小管NHE3在正常血压稳态和高血压发病机制中的作用尚未清楚。最近,本课题组使用新型基因修饰全身、肾脏、近端小管特异性NHE3敲除小鼠模型,探讨了肠道和肾近端小管NHE3在维持基础血压稳态和在血管紧张素Ⅱ诱导高血压发展中的关键作用和潜在机制。这些新发现不仅支持了小肠和肾近端小管NHE3在维持正常血压以及在血管紧张素Ⅱ依赖性高血压发展中发挥的关键作用,同时还可能为治疗人类难控制性高血压提供潜在的新的治疗靶点。 展开更多
关键词 血管紧张素Ⅱ 高血压 肾脏 钠氢交换因子3 近端小管
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三种温和还原法制备Pt/SDB
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作者 付昆 高月 +4 位作者 汤义萍 朱磊 刘才林 杨海君 任先艳 《化学研究与应用》 CAS 北大核心 2024年第5期1092-1100,共9页
Pt/SDB是液相催化交换(LPCE)反应处理核电产生含氚废水的一种很有前途的催化剂。采用悬浮聚合法制备得到介孔聚苯乙烯-二乙烯基苯(SDB),以硼氢化钠(SBH)、水合肼(HH)或乙二醇(EG)为还原剂,温和还原法制备SDB载体负载铂活性颗粒,产物分... Pt/SDB是液相催化交换(LPCE)反应处理核电产生含氚废水的一种很有前途的催化剂。采用悬浮聚合法制备得到介孔聚苯乙烯-二乙烯基苯(SDB),以硼氢化钠(SBH)、水合肼(HH)或乙二醇(EG)为还原剂,温和还原法制备SDB载体负载铂活性颗粒,产物分别记为Pt/SDB-SBH、Pt/SDB-HH或Pt/SDB-EG。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、氮气吸附脱附和氢-水催化交换实验等对其结构形貌及催化活性表征。结果表明:Pt/SDB-SBH疏水催化剂具有突出的性能和优异的催化活性,Pt纳米颗粒平均粒径约为3.3 nm,Pt^(0)组分比例为72.0%,催化交换柱效率达65.0%,并在120 min保持稳定。为低温还原制备Pt/SDB疏水催化剂提供了一种新的策略。 展开更多
关键词 液相催化交换(LPCE) 铂/苯乙烯-二乙烯基苯共聚物(Pt/SDB) 硼氢化钠还原法 水合肼还原法 乙二醇还原法
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示范快堆中间热交换器材料316H钢钠中老化行为研究
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作者 纪琤 张金权 +1 位作者 阮章顺 和雅洁 《科技资讯》 2024年第2期117-120,共4页
316H钢是中国示范快堆中间热交换器的主要材料,随着运行时间的增加,其老化效应不断累积。为探索316H钢在示范快堆中间热交换器运行工况下的老化行为,此研究分别在353℃和535℃静态钠条件下对316H钢管材和板材试样进行了1000~8000 h的相... 316H钢是中国示范快堆中间热交换器的主要材料,随着运行时间的增加,其老化效应不断累积。为探索316H钢在示范快堆中间热交换器运行工况下的老化行为,此研究分别在353℃和535℃静态钠条件下对316H钢管材和板材试样进行了1000~8000 h的相容性试验,并对试验后的样品开展微观表征、腐蚀速率测量以及力学性能测试等分析。结果显示:353℃条件下试样几乎不发生腐蚀现象,而在535℃条件下,高温加速了扩散使得材料的老化行为显著,随着试验时间的增加,材料在钠中的腐蚀转为稳态阶段。研究表明:316H钢在钠中的老化行为受到钠的温度、浸泡时间以及材料制造工艺等因素影响,在低氧低碳的低温钠环境中有较好的抗老化能力,在温度相对较高、时间较长的钠环境中存在老化迹象。 展开更多
关键词 316H钢 钠冷快堆 中间热交换器 老化 腐蚀速率
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High Na-ion conductivity andmechanical integrity of anion-exchanged polymeric hydrogel electrolytes for flexible sodium ion hybrid energy storage
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作者 JungWoo Hong Harpalsinh H.Rana +10 位作者 Jeong Hee Park Jun Su Kim Sang Joon Lee Gun Jang Tae Hoon Kang Kang Ho Shin Sang Ha Baek Wooseok Yang Kwang Ho Kim Ju-Hyuk Lee Ho Seok Park 《SusMat》 SCIE EI 2024年第1期140-153,共14页
The polymeric gel electrolytes are attractive owing to their higher ionic conductivities than those of dry polymer electrolytes and lowered water activity for enlarged potential window.However,the ionic conductivity a... The polymeric gel electrolytes are attractive owing to their higher ionic conductivities than those of dry polymer electrolytes and lowered water activity for enlarged potential window.However,the ionic conductivity and mechanical strength of the Na-ion conducting polymeric gel electrolytes are limited by below 20 mS cm−1 and 2.2 MPa.Herein,we demonstrate Na-ion conducting and flexible polymeric hydrogel electrolytes of the chemically coupled poly(diallyldimethylammonium chloride)-dextrin-N,N′-methylene-bisacrylamide film immersed in NaClO_(4) solution(ex-DDA-Dex+NaClO_(4))for flexible sodium-ion hybrid capacitors(f-NIHC).In particular,the anion exchange reaction and synergistic interaction of ex-DDA-Dex with the optimum ClO_(4)−enable to greatly improve the ionic conductivity up to 27.63 mS cm−1 at 25◦C and electrochemical stability window up to 2.6 V,whereas the double networking structure leads to achieve both the mechanical strength(7.48 MPa)and softness of hydrogel electrolytes.Therefore,the f-NIHCs with the ex-DDA-Dex+NaClO_(4) achieved high specific and high-rate capacities of 192.04 F g^(−1)at 500 mA g^(−1)and 116.06 F g^(−1)at 10000 mA g^(−1),respectively,delivering a large energy density of 120.03Wh kg^(−1)at 906Wkg^(−1)and long cyclability of 70%over 500 cycles as well as demonstrating functional operation under mechanical stresses. 展开更多
关键词 anion exchange chemistry flexible energy storage hybrid energy storage hydrogel electrolytes renewable electrolytes sodium storage
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