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1.
研究了柠檬酸(CA)螯合Fe2+活化过碳酸盐体系中投加盐酸羟胺(HAH)对三氯乙烯(TCE)的去除效果。结果发现,HAH能有效将Fe3+还原为Fe2+,强化TCE的去除效果。当TCE初始浓度为0.15 mmol/L时,nSPCnFe2+nTCE=5:3:1时,在CA浓度为0.5 mmol/L条件下,HAH最佳投加浓度为1.5 mmol/L,此时TCE去除率为99.6%。·OH对TCE降解的贡献度为79.2%,O2-·的贡献度为21.9%。HAH可减轻HCO3-对TCE降解的抑制效应,中间产物为甲酸、NO2-和NO3-。HAH利于SPC/Fe2+/CA体系降解TCE,该结果可为实际TCE污染地下水修复提供技术支撑。  相似文献   

2.
采用溶液球磨法制备了丁腈橡胶(NBR)/硫酸铁(Fe2(SO43)复合材料,Fe2(SO43颗粒的平均粒径由10.23 μm降低到1.13 μm,粒径大小分布变窄。电子顺磁共振谱(ESR)以及X射线光电子能谱分析(XPS)证明了丁腈橡胶中的-CN与Fe2(SO43中的Fe3+发生了配位反应。随着Fe2(SO43添加量的增加,复合材料的玻璃化转变温度(Tg)与交联密度逐渐增加。当Fe2(SO43添加量为15 phr (每100份基体中的填料份数)时,NBR/Fe2(SO43复合材料综合力学性能最好,复合材料的拉伸强度比纯NBR的拉伸强度提高了约12.8倍。采用溶液球磨法制备出的NBR/Fe2(SO43复合材料的交联密度、拉伸强度、硬度、回弹性、伸张疲劳系数以及耐老化性能均高于干法制备的NBR/Fe2(SO43复合材料的相应值。  相似文献   

3.
设计并熔制了作为蓝宝石充填材料用的SiO2-TiO2-RO-R''2O(其中R代表二价碱金属离子Ba2+、Zn2+,R''代表一价碱金属离子Na+、K+)系列玻璃。通过对玻璃的物理性能(密度和折射率)、热稳定性(玻璃化转变温度和析晶温度)以及玻璃骨架结构的探讨,研究了混合碱效应对玻璃性能的影响。结果表明,该系列玻璃在n(Na+):n(K+)=2:3时,其密度、折射率等物理性能符合蓝宝石充填要求,且热稳定性强,充填过程不容易发生析晶,可作为蓝宝石充填材料。  相似文献   

4.
将中空纤维膜反应器和芬顿试剂结合脱除烟气中的Hg0。研究了不同参数以及SO2、NO和O2等杂质气体对Hg0脱除的影响。结果表明:随着H2O2浓度、Fe2+浓度、溶液初始pH和温度的增加,Hg0脱除率先增加后降低,其最佳工作条件是H2O2浓度为6 mmol/L,Fe2+浓度为9 mmol/L,溶液初始pH为2.5,温度为20℃;增大液气比和通过减小气相流量增大停留时间均对Hg0脱除有增强作用,当液气比超过0.11时,Hg0的脱除率不再增加;当气相流量为0.6 L/min时,Hg0脱除率超过85%;SO2、NO对Hg0的脱除有抑制作用,O2对Hg0的脱除几乎没有影响;还测定出温度20℃下中空纤维膜反应器的比相界面积a=270.29 m-1和传质动力学参数kL=8.13×10-4 m/s,kG=0.786×10-6 mol/(m2·s·Pa)。  相似文献   

5.
采用电子探针(EPMA)、激光拉曼(Raman)光谱、1H-核磁共振谱(1H-NMR)和电子顺磁共振吸收谱(EPR)对四川石棉县的蛇纹石猫眼进行了测试分析。结果表明:蛇纹石猫眼的主要平均化学组成(质量分数)为SiO2 43.56%,MgO 40.52%,FeO和Fe2O3混合物为2.14%,MnO 0.05%。其中,致色离子主要为顺磁离子Fe3+和Mn2+;蛇纹石猫眼Raman谱峰中3 700 cm-1附近的-OH谱带分裂,并向低波数方向位移,主要与其不同颜色样品成分中Fe3+和Mn2+的含量、占位以及Fe3+和Mn2+对Mg2+类质同象替换的程度有关;Fe3+和Mn2+同时占位于蛇纹石Mg-O(OH)八面体位置,随样品的颜色由浅黄绿色向暗褐绿色转变,Fe3+和Mn2+类质同象替代Mg2+的程度增强,从而使Mg-O(OH)八面体部分分裂为((Fe3+、Mn2+),Mg2+)-O(OH)八面体。1H-NMR的测试结果也证实了这一点。  相似文献   

6.
[目的] 系统研究参麦注射液体外抗氧化性能。[方法] 采用铁还原抗氧化能力 (FRAP)法、1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法、一氧化氮(NO)自由基清除法、过氧化氢(H2O2)清除法、亚铁(Fe2+)离子螯合法分别测试不同稀释倍率参麦注射液的总抗氧化能力、DPPH·清除活性、NO·清除活性、H2O2清除活性和Fe2+离子螯合活性,并将结果与0.1mg/mL 2,6-二叔丁基对甲酚(BHT)、10 mmol/L水溶性维生素E(Trolox)和10%柠檬酸的结果进行比较。[结果] 参麦注射液具有一定的体外抗氧化能力,总抗氧化能力和对自由基清除活性均呈浓度正依赖性;10倍稀释参麦注射液总抗氧化能力显著低于BHT和Trolox (P<0.01),但高于柠檬酸(P<0.01);参麦注射液对不同自由基清除能力存在差异,其强弱顺序为:NO·[(54.4±6.6)%] > Fe2+离子螯[(42.6±3.2)%] > DPPH·[(36.2±2.8)%] > H2O2[(23.5±1.2)%]。[结论] 参麦注射液体外抗氧化活性研究将为其抗氧化药理学机制提供了实验依据。  相似文献   

7.
N,N-二甲基甲酰胺(DMF)作为一种万能溶剂在工业中被广泛应用,但它有毒性、难以生物降解。本文采用Fenton法处理DMF模拟废水,考察了pH、反应时间、氧化剂投加量等条件对处理效果的影响,同时探讨了Cl-和SO42-对反应的影响。研究结果表明:处理1 g/L的DMF模拟废水,最佳反应条件为:w=30% H2O2的投加量为40 mL/L,pH=2.0,n(H2O2):n(Fe2+)=3:1,反应时间2.5 h,在该条件下出水化学需氧量(COD)小于100 mg/L;Cl-对Fenton法处理DMF废水有着十分强的抑制作用,1 g/L就会使出水COD由90 mg/L上升到250 mg/L;而SO42-对Fenton反应的处理效果影响很小,当ρSO42->10 g/L时有一定的促进作用。  相似文献   

8.
目的探讨ATP敏感钾通道(KATP)在外源性硫化氢(H2S)诱导人子宫肌瘤细胞凋亡中的作用。方法用硫氢化钠(NaHS)作为H2S的供体处理原代培养的人子宫肌瘤细胞,KATP通道抑制剂格列本脲(Gly)预处理细胞。实验分为对照组、不同浓度NaHS组、ATP敏感性钾通道(KATP)抑制剂组和Gly + NaHS组。用流式细胞术检测细胞凋亡率,采用实时定量PCR和Western blot分别检测p53和bcl-2 mRNA和蛋白的表达。结果与对照组比较,NaHS(10-4 和10-3 mol/L)处理人子宫肌瘤细胞24和48 h后以剂量和时间依赖的方式增加了细胞的凋亡率(均P<0.05)。与对照组比较,NaHS(10-4 mol/L)处理人子宫肌瘤细胞24 h后p53的表达显著增加(P<0.05),而bcl-2表达显著降低(P<0.05)。Gly没有影响人子宫肌瘤细胞的凋亡率、p53和bcl-2的表达,但部分地拮抗NaHS的致凋亡作用以及NaHS诱导的子宫肌瘤细胞中p53表达的上调和bcl-2表达的下调(均P<0.05)。结论外源性H2S诱导子宫肌瘤细胞凋亡,其机制与H2S开放KATP通道有关。  相似文献   

9.
目的 观察不同血液净化方式对中分子尿毒症毒素β2-微球蛋白(β2-MG)、甲状旁腺素(PTH)等的清除效果,为临床合理选择尿毒症患者血液净化方式提供依据。方法 研究是64例在笔者医院进行血液净化治疗的尿毒症患者,同时根据血液净化方式的差异进行分组∶单纯血液透析组(HD,n=30),血液透析合并血液灌流组(HD+HP,n=15),血液透析滤过组(HDF,n=19)。采集治疗前后患者血清,ELISA法检测β2-MG、PTH水平以评价不同净化方式对中分子尿毒症毒素的清除率;检测临床肾功能指标和钙离子(Ca2+)、钾离子(K+)、钠离子(Na+)、氯离子(Cl-),反映不同净化方式对低分子物质的清除率。结果 与HD、HD+HP组比较,HDF组治疗后血液中分子物质β2-MG和PTH水平均显著下降(P<0.01),清除效果明显;与HD组比较,HD+HP组治疗后PTH显著下降(P<0.01),治疗后β2-MG的清除率比较,差异无统计学意义(P>0.05);3组BUN、Scr清除率、KT/V值透析前后血差异无统计学意义,Ca2+、K+、Na+、Cl-改善比较,差异无统计学意义(P>0.05)。结论 对于尿毒症患者体内毒素的清除,HDF的清除效果最佳,其次是HD+HP,HD对中分子物质的清除无明显效果。  相似文献   

10.
[目的] 研究5种细胞色素P450酶亚型的特异性探针底物非那西丁(CYP1A2)、右美沙芬(CYP2D6)、甲苯磺丁脲(CYP2C9)、奥美拉唑(CYP2C19)、咪达唑仑(CYP3A4)在人和大鼠肝微粒体中的酶动力学特征,比较两种探针底物法的适用性。[方法] 5种特异性探针底物分别经人或大鼠的肝微粒体代谢反应后,采用高效液相色谱法测定特异性探针底物的代谢速率,根据底物浓度-代谢速率曲线计算酶动力学常数。[结果] 单探针与混合探针两种方法在人肝微粒体中所得的VmaxKm值具有一致性;而在大鼠肝微粒体中所得的Km具有一定差异,表明该混合探针底物法在用于药物对大鼠肝微粒体中的细胞色素P450酶活性评价时可能会出现一定程度的影响。[结论] 在人肝微粒体中,两种探针底物法的VmaxKm值具有一致性,因而混合探针底物法可代替单探针法用于细胞色素P450酶活性评价;在大鼠肝微粒体中,探针底物混合后可使得部分探针底物的Km值升高,与酶亲和力下降,在细胞色素P450酶活性评价中可能出现假阴性结果。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

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