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51.
52.
Wen-Yan Pan Liang-Liang Peng Wen-Jing Wang Yuan-Yuan Li Xue-Ling Wei 《RSC advances》2021,11(59):37131
Zeolite membranes with unique physical and chemical properties are emerging as attractive candidates for membrane separation. However, defects in the zeolite layer seriously affect their molecular sieving performance. In this study, a novel strategy for preparing compact zeolite membranes on rough supports with the assistance of a reticulated hydrotalcite layer was developed. The reticulated hydrotalcite layer was grown on the inner surface of a 170 mm length ceramic tube by an in situ hydrothermal method, and a NaA zeolite membrane was prepared on this reticulated layer by the microwave-heating method. The hydrotalcite interlayer could not only improve the smoothness and regularity of the surface of the support but also fix the Si/Al active ingredients using its reticulate structure, finally effectively improving the quality and stability of the zeolite layer. The optimal molar ratio of the synthesis solution for the synthesis of the zeolite membrane was 3Na2O : 2SiO2 : Al2O3 : 200H2O. The permeance flux of H2 through the zeolite membrane synthesized under the optimal conditions was high as 0.47 × 10−6 mol m−2 s−1 Pa−1, and its permselectivity for H2 over N2 was 4.7, which was higher than the corresponding Knudsen diffusion coefficient. This study provides a new idea for the preparation of defect-free membranes on rough supports.Reticulated hydrotalcite interlayer controls infiltration of active ingredients into the support, improving the quality and stability of the zeolite membrane. 相似文献
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目的探讨急性缺血性脑卒中血管内治疗的方法、疗效和安全性。方法回顾性分析血管内治疗的大血管闭塞的急性缺血性脑卒中患者21例。10例为阿替普酶静脉溶栓后桥接血管内治疗,11例直接行血管内治疗。其中机械取栓12例,机械取栓+支架植入3例,单纯颈动脉支架植入3例,机械取栓+动脉溶栓1例,机械取栓+动脉溶栓+支架植入1例,单纯动脉溶栓1例。评估术中mTICI再通等级、并发症及术后随访第90天m RS评分,分析疗效与安全性。结果21例患者前循环卒中18例,后循环卒中3例。NIHSS评分平均15. 81±6. 44分。20例患者术后血管再通达mTICI 2 b-3级。术中并发出血1例,术后大量颅内出血1例,无症状少量颅内出血4例。术后高灌注综合征8例,其中4例行去骨瓣减压术,最终死亡5例(23. 81%)。术后随访第90天mRS评分0~2分8例。结论经充分评估并及时采取适宜的单一或多种血管内治疗方法对于大血管闭塞导致的急性缺血性脑卒中患者安全有效。 相似文献
55.
Chao-Yang Tan Yan-Ping Wang Yuan-Yuan Han Bi-Han Lu Wei Ji Li-Cang Zhu Yang Wang Wen-Yan Shi Li-Ya Shan Liang Zhang Ke-Tao Ma Li Li Jun-Qiang Si 《中国神经再生研究》2020,(5):912-921
Sodium-potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) are associated with the transmission of peripheral pain.We investigated whether the increase of NKCC1 and KCC2 is associated with peripheral pain transmission in dorsal root ganglion neurons.To this aim,rats with persistent hyperalgesia were randomly divided into four groups.Rats in the control group received no treatment,and the rat sciatic nerve was only exposed in the sham group.Rats in the chronic constriction injury group were established into chronic constriction injury models by ligating sciatic nerve and rats were given bumetanide,an inhibitor of NKCC1,based on chronic constriction injury modeling in the chronic constriction injury + bumetanide group.In the experiment measuring thermal withdrawal latency,bumetanide (15 mg/kg) was intravenously administered.In the patch clamp experiment,bumetanide (10 μg/μL) and acutely isolated dorsal root ganglion neurons (on day 14) were incubated for 1 hour,or bumetanide (5 μg/μL) was intrathecally injected.The Hargreaves test was conducted to detect changes in thermal hyperalgesia in rats.We found that the thermal withdrawal latency of rats was significantly decreased on days 7,14,and 21 after model establishment.After intravenous injection of bumetanide,the reduction in thermal retraction latency caused by model establishment was significantly inhibited.Immunohistochemistry and western blot assay results revealed that the immune response and protein expression of NKCC1 in dorsal root ganglion neurons of the chronic constriction injury group increased significantly on days 7,14,and 21 after model establishment.No immune response or protein expression of KCC2 was observed in dorsal root ganglion neurons before and after model establishment.The Cl^– (chloride ion) fluorescent probe technique was used to evaluate the change of Cl^– concentration in dorsal root ganglion neurons of chronic constriction injury model rats.We found that the relative optical density of N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (a Cl^– fluorescent probe whose fluorescence Cenintensity decreases as Cl– concentration increases) in the dorsal root ganglion neurons of the chronic constriction injury group was significantly decreased on days 7 and 14 after model establishment.The whole-cell patch clamp technique revealed that the resting potential and action potential frequency of dorsal root ganglion neurons increased,and the threshold and rheobase of action potentials decreased in the chronic constriction injury group on day 14 after model establishment.After bumetanide administration,the above indicators were significantly suppressed.These results confirm that CCI can induce abnormal overexpression of NKCC1,thereby increasing the Cl^– concentration in dorsal root ganglion neurons;this then enhances the excitability of dorsal root ganglion neurons and ultimately promotes hyperalgesia and allodynia.In addition,bumetanide can achieve analgesic effects.All experiments were approved by the Institutional Ethics Review Board at the First Affiliated Hospital,College of Medicine,Shihezi University,China on February 22,2017 (approval No.A2017-169-01). 相似文献
56.
目的探讨亚硝基铁氰化钠(SNP)来源的NO体外杀伤旋毛虫肌幼虫的作用及其相关机制。方法制作浓度为1 000条/ml的旋毛虫肌幼虫悬液。培养板每孔加入0.1 ml肌幼虫悬液,再加入SNP,使其终浓度分别为0.02、0.05、0.10、0.20、0.50 mmol/L和1.00 mmol/L,并设空白对照组,37℃5%CO2培养箱中孵育4 d后收集各孔肌幼虫,镜检计数,计算并比较各组肌幼虫死亡率。另于培养板中每孔加入0.1 ml肌幼虫悬液,分别设A组(对照组,1.00 mmol/L SNP)、B组(0.15 mmol/L Fe SO4+1.00 mmol/L SNP)、C组(1.00 mmol/L L-半胱氨酸+1.00 mmol/L SNP)、D组(0.15 mmol/L Fe SO4+1.00mmol/L L-半胱氨酸+1.00 mmol/L SNP)、E组(0.15 mmol/L Hb+1.00 mmol/L SNP),培养、检测方法同前,计算并比较各组肌幼虫死亡率。结果 0.02 mmol/L SNP组与空白对照组的旋毛虫肌幼虫死亡率分别为(5.50±1.80)%和(4.93±0.25)%(P0.05)。0.05、0.10、0.20、0.50、1.00 mmol/L SNP组虫体死亡率分别为(20.19±2.71)%、(29.21±2.12)%、(41.81±2.03)%、(47.85±3.79)%和(60.98±5.19)%,与空白对照组比较差异均有统计学意义(P均0.05)。旋毛虫肌幼虫死亡率与SNP浓度呈正相关(rs=0.875,P0.05)。B、C、D、E组肌幼虫死亡率分别为(49.48±1.34)%、(47.29±2.79)%、(26.28±1.37)%和(17.93±3.49)%,均较A组(60.98±5.19)%有所下降(P均0.05)。结论 SNP来源NO对体外培养的旋毛虫肌幼虫具有杀伤作用,而血红蛋白、硫酸亚铁、L-半胱氨酸对该杀伤具有抑制作用,以血红蛋白抑制效果最显著。 相似文献
57.
目的 探讨E-选择素、CD14及血管细胞粘附分子(vascular cell adhesion molecule 1,VCAM1)水平与生殖道沙眼衣原体感染的相关性.方法 选取86例生殖道沙眼衣原体感染患者为观察组;根据生殖道沙眼衣原体感染患者是否伴有炎症,分为感染伴炎症组和感染无炎症组,各43例;同时,选取36例健康体检者为对照组;采用双抗体夹心酶联免疫吸附法(ELISA)测定所有研究对象的血清E-选择素、CD14及VCAM1水平,并作对比分析;观察组患者采取炎克宁冲剂结合阿奇霉素治疗,对比治疗前后的血清E-选择素、CD14及VCAM1水平,并与对照组作对比分析.结果 观察组的血清E-选择素、CD14及VCAM1水平均显著高于对照组;差异具有统计学意义(P<0.05);感染伴炎症组与感染无炎症组的血清E-选择素、CD14及VCAM1水平的差异具有统计学意义(P<0.05);观察组患者采取炎克宁冲剂结合阿奇霉素治疗后,临床总有效率为94.19%,生殖道沙眼衣原体转阴率为87.21%;治疗后的血清E-选择素、CD14及VCAM1水平显著低于治疗前水平,差异具有统计学意义(P<0.05);与对照组对比,差异无统计学意义(P>0.05).结论 生殖道沙眼衣原体感染的病情进展与E-选择素、CD14及VCAM1水平密切相关,通过监测E-选择素、CD14及VCAM1水平,可为生殖道沙眼衣原体感染的治疗、评估疗效及预后而提供依据. 相似文献
58.
目的:探讨阻断CD86协同刺激分子对自然流产模型孕鼠TGF-β1和PAI-1的表达及妊娠结局的影响。方法:实验组于妊娠第4.5天腹腔注射大鼠抗小鼠CD86单抗,实验对照组注射大鼠同型IgG2b,而正常妊娠组不做任何处理。于妊娠第13.5天计算胚胎吸收率,用免疫组化测定TGF-β1和PAI-1的表达。结果:(1)实验组的胚胎吸收率显著低于实验对照组(P〈0.05)。(2)实验组蜕膜细胞中TGF-β1和PAI-1的表达均显著高于实验对照组(P〈0.05)。结论:妊娠早期阻断CD86协同刺激分子信号途径可使母胎界面中的TGF-β1和PAI-1分别通过各自不同的途径来发挥免疫耐受作用并且使自然流产模型孕鼠的胚胎吸收率降低至正常妊娠水平。 相似文献
59.
microRNA(miR)与急性白血病的发生密切相关.为分析急性白血病患者与正常人骨髓细胞中miR-143的差异表达情况,常规提取50例急性白血病患者及20例正常人骨髓细胞中的总RNA,应用实时荧光定量PCR的方法检测标本中miR-143的表达状况.结果表明:急性白血病患者骨髓细胞中miR-143表达明显下调(p<0.05);化疗缓解后表达明显上调;miR-143的表达与靶基因DNMT3A呈负相关.结论:miR-143在白血病病人骨髓细胞中的表达下调,这可能与白血病的发生发展有关. 相似文献
60.
目的:利用酵母双杂交技术筛选与ERβ相互作用的蛋白,为进一步研究ERβ的功能奠定基础。方法:从乳腺cDNA文库中钓取ERβ-AF1 cDNA,构建诱饵蛋白载体pAS2-1-ERβ—AF1,利用酵母双杂交筛选技术,在乳腺cDNA文库中筛选与ERβ-AF1相互作用的蛋白。将含有pACT2-候选基因的酵母菌与含有pAS2—1-ERp—AF1的酵母菌进行交配实验,利用LacZ报告基因检测ERβ—AF1与候选蛋白之间是否存在相互作用。然后将ERp—AF1和候选蛋白分别构建到pGEx-KG和pET-28a上,并纯化GST-ERβ-AF1和His-侯选蛋白融合蛋白,利用GST沉淀实验进一步验证ERβ-AF1和候选蛋白的体外相互作用。结果:所获取的候选蛋白为CTGF,是CCN多肽家族成员。交配实验表明,CTGF与ERβ-AF1特异相互作用,而不与空载体或BRCT1对照相互作用。GST沉淀实验进一步验证,CTGF与ERβ、ERα均存在相互作用,但与CTGF同源性较高的NOV蛋白却不与ERβ、ERa结合。结论:CTGF和ERβ存在特异的相互作用。 相似文献