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外周血CD8+CD28-CD57+T淋巴细胞对老年脓毒症患者预后的预测价值
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作者 张小玲 赵玉杰 +3 位作者 刘敏龙 周丽 郭蕾 马琪 《西部医学》 2024年第2期232-236,共5页
目的 探讨外周血CD8+CD28-CD57+T淋巴细胞对老年脓毒症患者预后的预测价值。方法 采用回顾性队列研究,选取2015年2月—2016年8月西安交通大学第二附属医院重症医学科住院的年龄≥60岁的脓毒症患者75例,依据ICU结局分为存活组(n=54)及死... 目的 探讨外周血CD8+CD28-CD57+T淋巴细胞对老年脓毒症患者预后的预测价值。方法 采用回顾性队列研究,选取2015年2月—2016年8月西安交通大学第二附属医院重症医学科住院的年龄≥60岁的脓毒症患者75例,依据ICU结局分为存活组(n=54)及死亡组(n=21)。收集患者一般资料,诊断脓毒症当天进行急性生理和慢性健康评分Ⅱ(APACHEⅡ)评分及序贯器官衰竭(SOFA)评分,检测外周血液标本TNF-a、IL-10及CD8+CD28-CD57+T淋巴细胞。结果 死亡组平均年龄大于存活组(P<0.05)。死亡组较存活组有更高的APACHEⅡ评分、SOFA评分及休克比例,差异均有统计学意义(P<0.05)。死亡组外周血CD8+CD28-CD57+T淋巴细胞、TNF-a、IL-10较存活组更高(P<0.05)。存活组的耐药菌感染比例低于死亡组,但差异无统计学意义(P>0.05)。无论单因素还是对一系列协变量进行调整的多因素Logistic回归分析均显示,较高的外周血CD8+CD28-CD57+T淋巴细胞比例与高的ICU死亡率相关(OR, 1.21;95%CI, 1.10~1.33)(OR, 1.30;95%CI, 1.07~1.58);APACHEⅡ评分预后预测的AUC为0.78(95%CI 0.67~0.90),将最适诊断界点22.5分作为预测死亡可能的临界点,敏感性和特异性分别为61.9%和75.2%。SOFA评分预后预测的AUC为0.80(95%CI,0.68~0.92),将最适诊断界点9.5分作为预测死亡可能的临界点,敏感性和特异性分别为71.4%和77.8%。外周血CD8+CD28-CD57+T淋巴细胞预后预测的AUC为0.91(95%CI,0.83~0.99),将最适诊断界点60.2%作为预测死亡可能的临界点,敏感性和特异性分别为81.0%和92.6%。结论 老年脓毒症患者外周血高CD8+CD28-CD57+T淋巴细胞比例与ICU死亡率增加相关,一定程度上可用于评估此类人群的病情严重程度及预测预后。 展开更多
关键词 CD8+CD28-cd57+T淋巴细胞 老年患者 脓毒症 预后
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Glycine-β-cyclodextrin-assisted cometabolism of phenanthrene and pyrene by Pseudomonas stutzeri DJP 1 from marine sediment
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作者 Junfeng JIANG Weijun TIAN +3 位作者 Zhiyang LU Meile CHU Huimin CAO Dantong ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期560-569,共10页
Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs).Unfortunately,due to low bio-accessibility and high biotoxicity,the come... Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs).Unfortunately,due to low bio-accessibility and high biotoxicity,the cometabolic degradation rate of HMW-PAHs is limited.Glycine-β-cyclodextrin(GCD)was obtained through amino modification ofβ-cyclodextrin(BCD)and added to cometabolic system of phenanthrene(PHE)and pyrene(PYR)to assist PYR biodegradation.Results show that the addition of GCD(100 mg/L)effectively improved the removal rate of PYR(20 mg/L)by 42.3%.GCD appeared to increase the bio-accessibility and reduce the biotoxicity of PHE and PYR,and then promoted the growth of Pseudomonas stutzeri DJP1 and stimulated the elevation of dehydrogenase(DHA)and catechol 12 dioxygenase(C12O)activities.The phthalate metabolic pathway was accelerated,which improved the cometabolic degradation.This study provided a new reference for the cometabolic degradation of HMW-PAHs. 展开更多
关键词 COMETABOLISM PHENANTHRENE PYRENE glycine-β-cyclodextrin biological accessibility biotoxicity
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Morphological Evolution of Self-Assembled Sodium Dodecyl Sulfate/Dodecyltrimethylammonium Bromide@Epoxy-β-Cyclodextrin Supramolecular Aggregates Induced by Temperature
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作者 Qingran Meng Wenwen Xu +2 位作者 Zuobing Xiao Qinfei Ke Xingran Kou 《Journal of Renewable Materials》 EI CAS 2024年第4期629-641,共13页
Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interact... Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interaction with guest molecules.The different forms of supramolecular self-assemblies can be transformed into each other under certain conditions.The regulation of supramolecular self-assembly is not only helpful to understand the self-assembly principle,but also beneficial to its application.In the present study,the self-assembly behavior of epoxy-β-cyclodextrin(EP-β-CD)and mixed anionic and cationic surfactant system(sodium dodecyl sulfate/dodecyltrimethylammonium bromide,SDS/DTAB)in aqueous solution was studied.Morphological and particle size characterization found that the SDS/DTAB@EP-β-CD complex,as the basic building unit,self-assembled into worm-like micelles at lower temperatures and vesicles at higher temperatures.Nuclear magnetic resonance(NMR)and Fourier transform infrared spectroscopy(FT-IR)analysis revealed that the driving force for the formation of vesicles and worm-like micelles was the hydrogen bonds between EP-β-CD molecules,while water molecules played an important role in promoting vesicle formation between SDS/DTAB@EP-β-CD units.Herein,the mechanism of the morphologic transformation of SDS/DTAB@EP-β-CD supramolecular aggregates induced by temperature was elucidated by exploring the self-assembly process,which may provide an excellent basis for the development of delivery carriers. 展开更多
关键词 Epoxy-β-cyclodextrin SDS/DTAB SELF-ASSEMBLY TEMPERATURE morphological evolution
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Adsorption of Phenanthrene in Soil to Biochar Modified by β-Cyclodextrin
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作者 Wanke Chen Qing Guo +3 位作者 Xiaoyan Wang Xiao Wang Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第9期44-54,共11页
In this study, the adsorption effect of β-cyclodextrin modified biochar (BC) on phenanthrene (PHE) in contaminated soil was investigated, aiming to provide an efficient and environmentally friendly remediation strate... In this study, the adsorption effect of β-cyclodextrin modified biochar (BC) on phenanthrene (PHE) in contaminated soil was investigated, aiming to provide an efficient and environmentally friendly remediation strategy for Polycyclic Aromatic Hydrocarbons (PAHs) contaminated soil. Through kinetic and isotherm analysis, β-CDBC-CA showed excellent phenanthrene adsorption performance, and the adsorption effect increased with the increase of time and was affected by temperature. The results show that β-CDBC-CA can not only effectively adsorb phenanthrene in soil, but also serve as a surfactant to help desorption phenanthrene adsorbed by soil organic matter and improve the efficiency of microbial degradation. The experimental data showed that the Elovich model could describe the adsorption behavior of β-CDBC-CA on phenanthrene well, while Langmuir and Freundlich models performed better in fitting parameters, revealing the adsorption mechanism of phenanthrene in contaminated soil by β-cyclodextrin-modified biochar. In addition, temperature has a significant effect on the adsorption capacity of β-CDBC-CA, and its application in soil remediation can be optimized by adjusting temperature. This study not only provides new materials and technical means for soil remediation but also provides important data support for an in-depth understanding of the environmental behavior of PAHs. By citing relevant research results, this study further improves the control and understanding of environmental risks of PAHs, which is of great significance for the protection of ecological environment and human health. 展开更多
关键词 PAHS BIOCHAR β-cyclodextrin MODIFICATION ADSORPTION Soil Remediation
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Synthesis and Characterization of β-Cyclodextrin Modified Biochar Environmental Remediation Materials
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作者 Qing Guo Xiao Wang +3 位作者 Wanke Chen Xiaoyan Wang Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第4期42-52,共11页
In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cy... In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cyclodextrin (β-CD) was used to modify biochar (BC). The prepared modified biochar materials were labeled with β-CDBC, β-CDBC-Na, β-CDBC-CA and β-CDBC-H, respectively. The infrared spectrum, X-ray diffractometer, scanning electron microscope and specific surface area of the four modified materials were tested. The results showed that the C-O stretching vibration peak at 1020 cm<sup>−</sup><sup>1</sup> of the modified materials was slightly offset compared with that of biochar. The characteristic absorption peaks of XRD pattern decrease obviously at 2θ = 26.7˚ and 29.5˚. It can be obviously observed on the electron microscope image that the surface is loaded or formed clathrates, and BET data and graphs also show that the specific surface area of the modified biochar is larger. Therefore, β-cyclodextrin successfully modified biochar and formed clathrates on the surface of biochar or was loaded in the pore structure of biochar, especially β-CDBC-CA achieved better modification effect. Because biochar and β-cyclodextrin raw materials are cheap, easy to prepare and green, and less prone to secondary pollution, it has a good advantage in environmental governance. 展开更多
关键词 BIOCHAR β-cyclodextrin MODIFICATION CLATHRATE Green Environmental Protection
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β-CD和CMCD对2-硝基联苯微生物降解的影响研究 被引量:2
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作者 蔡邦成 高士祥 +3 位作者 韩尚富 陆根法 宋莉娟 邵云 《环境科学与技术》 CAS CSCD 北大核心 2006年第8期1-2,共2页
对β-环糊精(β-CD)和羧甲基-β-环糊精(CMCD)对一株不动杆菌属菌株降解2-硝基联苯的影响进行研究。结果表明β-CD和CMCD均能增加2-硝基联苯的表观溶解度和促进其微生物降解,CMCD的促进作用比β-CD更明显;环糊精对2-硝基联苯降解的促进... 对β-环糊精(β-CD)和羧甲基-β-环糊精(CMCD)对一株不动杆菌属菌株降解2-硝基联苯的影响进行研究。结果表明β-CD和CMCD均能增加2-硝基联苯的表观溶解度和促进其微生物降解,CMCD的促进作用比β-CD更明显;环糊精对2-硝基联苯降解的促进作用大小与增溶作用的强弱表现出相同的趋势。 展开更多
关键词 Β-环糊精 羧甲基-β-环糊精 2-硝基联苯 不动杆菌 降解
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升温速率对β-CD/1-MCP热分解反应动力学的影响 被引量:6
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作者 何翊 孙挺 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第4期469-472,共4页
用程序升温热重法对-βCD与1-MCP包结物的热分解动力学进行了研究,考察了升温速率对TG/DTG谱图的影响,并用单一升温速率法和多个升温速率组合法分别作了动力学分析.结果表明:动力学参数(Tm和(dα/dT)m)均随着升温速率的升高而增大,两种... 用程序升温热重法对-βCD与1-MCP包结物的热分解动力学进行了研究,考察了升温速率对TG/DTG谱图的影响,并用单一升温速率法和多个升温速率组合法分别作了动力学分析.结果表明:动力学参数(Tm和(dα/dT)m)均随着升温速率的升高而增大,两种计算方法得到的动力学参数是不同的,单一升温速率法计算出的E和A值遵循关系式:lnA=0.1059E+1.013,即存在动力学补偿效应;多个升温速率组合法对E的计算,则依赖于升温速率的组合. 展开更多
关键词 β-环糊精 1-甲基环丙烯 升温速率 热分解动力学 程序升温热重法
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β-Cyclodextrin promoted oxidation of aldehydes to carboxylic acids in water 被引量:7
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作者 Dong Po Shi Hong Bing Ji 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期139-142,共4页
A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with... A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with β-cyclodextrin (β-CD) were oxidized selectively with excellent yields. 展开更多
关键词 Substrate-selective OXIDATION β-cyclodextrin (β-cd ALDEHYDES
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DM-β-CD对盐酸二氢埃托啡离体鼻黏膜渗透的影响 被引量:1
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作者 贾立华 付聪 +1 位作者 丁桥兰 高永良 《中国新药杂志》 CAS CSCD 北大核心 2007年第7期551-553,共3页
目的:考察不同条件下二甲基-β-环糊精(DM--βCD)对盐酸二氢埃托啡促渗作用的影响。方法:采用透皮实验用扩散池装置用于透黏膜实验,HPLC法测定黏膜渗透药量,分别考察DM-β-CD的质量浓度和加入方式对渗透的影响。结果:DM-β-CD的质量浓... 目的:考察不同条件下二甲基-β-环糊精(DM--βCD)对盐酸二氢埃托啡促渗作用的影响。方法:采用透皮实验用扩散池装置用于透黏膜实验,HPLC法测定黏膜渗透药量,分别考察DM-β-CD的质量浓度和加入方式对渗透的影响。结果:DM-β-CD的质量浓度与黏膜渗透率不呈线性关系,DM-β-CD的加入方式对黏膜渗透速率有较强的影响。结论:促渗剂质量浓度为10 mg.mL-1,以超声包合法制备DM-β-CD和盐酸二氢埃托啡的包合物,可使渗透速率达到最大。 展开更多
关键词 盐酸二氢埃托啡 二甲基-β-环糊精(DM-β-cd) 包合物 渗透速率
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β-CD去除蛋黄卵磷脂中胆固醇工艺的研究 被引量:1
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作者 李硕绵 李妹玲 +2 位作者 乔宁 王迎春 董世山 《黑龙江畜牧兽医》 CAS 北大核心 2015年第6期137-139,288,共4页
为了优化蛋黄卵磷脂中胆固醇的去除工艺,建立适合大规模生产低胆固醇蛋黄卵磷脂的工艺流程,试验采用薄层色谱法和皂化比色法定性和定量测定胆固醇,利用β-环状糊精(β-CD)的包埋吸附作用去除胆固醇,研究不同条件参数对胆固醇去除率的影... 为了优化蛋黄卵磷脂中胆固醇的去除工艺,建立适合大规模生产低胆固醇蛋黄卵磷脂的工艺流程,试验采用薄层色谱法和皂化比色法定性和定量测定胆固醇,利用β-环状糊精(β-CD)的包埋吸附作用去除胆固醇,研究不同条件参数对胆固醇去除率的影响。结果表明:10 g鲜蛋黄液经乙醇萃取卵磷脂后添加1.6 gβ-CD,常温下混合搅拌10 min,5 000 r/min离心10 min,得到的卵磷脂制品胆固醇去除率可达99.00%。 展开更多
关键词 蛋黄 卵磷脂 胆固醇 β-环状糊精(β-cd) 优化 工艺
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Electrokinetic movement of multiple chlorobenzenes in contaminated soils in the presence of β-cyclodextrin 被引量:3
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作者 YUAN Song-hu WAN Jin-zhong LU Xiao-hua 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第8期968-976,共9页
This study investigated the electrokinetic (EK) behavior of multiple chlorobenzenes, including 1,2,3,4-tetrachlorobenzene (TeCB), 1,2,4,5-tetrachlorobenzene (i-TeCB), and 1,2,3-trichlorobenzene (TCB) in contam... This study investigated the electrokinetic (EK) behavior of multiple chlorobenzenes, including 1,2,3,4-tetrachlorobenzene (TeCB), 1,2,4,5-tetrachlorobenzene (i-TeCB), and 1,2,3-trichlorobenzene (TCB) in contaminated clayed soils. The effect of β-cyclodextrin (β- CD) on the EK removal of the chlorobenzenes was studied. The largest removal was obtained when Na2CO3/NaHCO3 buffer was used as anodic purging solution without β-CD. The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow, greater solubility led to higher removal efficiency. The addition of β-CD inhibited the EK removal efficiency of all chlorobenzenes. The inhibition increased with the increase of β-CD concentration. With the same β-CD concentration, the inhibition increased with the rise of electric potential. It was found that the inclusion compounds between β-CD and chlorobenzenzes were less soluble than chlorobenzenes. The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil. It was feasible to use the EK technology to remove chlorobenzenes in contaminated soils using water as the anodic flushing solution. The addition of β-CD was not recommended for the EK removal of chlorobenzenes. 展开更多
关键词 CHLOROBENZENES ELECTROKINETIC soil remediation β-cyclodextrin (β-cd
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全衍生化β-CD键合固定相的合成及其在HPLC中的应用研究进展 被引量:7
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作者 许志刚 艾萍 +2 位作者 袁黎明 周岩 韩熠 《云南师范大学学报(自然科学版)》 2005年第3期45-47,共3页
文章通过查阅大量文献,研究了6位单取代β-CD及其全衍生化产物的不同合成方法,并报到了各种全衍生化β-CD作为高效液相色谱键合固定相的合成方法及其在HPLC中的应用。
关键词 β-cd 全衍生化β-cd 键合固定相 HPLC
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Fe^(3+)-CdS/TiO_2复合半导体光催化剂的制备与表征 被引量:10
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作者 苏碧桃 董娜 +4 位作者 慕红梅 雷自强 佟永纯 白洁 王克 《精细化工》 EI CAS CSCD 北大核心 2007年第9期856-859,898,共5页
采用溶胶-凝胶法制备了系列不同配比的Fe3+-CdS/TiO2光催化材料,用TEM、EDS、XRD、UV-vis等技术对其形貌、结构和光吸收特性进行了表征。以亚甲基蓝(MB)的脱色降解为模型反应,考察了光源、煅烧温度、煅烧时间、掺杂Fe3+和CdS对催化剂催... 采用溶胶-凝胶法制备了系列不同配比的Fe3+-CdS/TiO2光催化材料,用TEM、EDS、XRD、UV-vis等技术对其形貌、结构和光吸收特性进行了表征。以亚甲基蓝(MB)的脱色降解为模型反应,考察了光源、煅烧温度、煅烧时间、掺杂Fe3+和CdS对催化剂催化性能的影响。结果表明,Fe3+掺杂和CdS半导体复合相结合的技术,可以使TiO2对光的响应拓展到整个紫外-可见光区;当n(Fe3+)∶n(CdS)∶n(TiO2)=0.005∶1∶1、煅烧温度为300℃、煅烧时间为1 h、光源为太阳光时,Fe3+-CdS/TiO2的光催化活性最高,在1 h内可以使亚甲基蓝(MB)溶液的降解率达98.62%。 展开更多
关键词 FE^3+ -cdS/TiO2 复合半导体 功能材料
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Biomimetic asymmetric Michael addition reactions in water catalyzed by amino-containing β-cyclodextrin derivatives 被引量:4
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作者 朱庆英 沈海民 +1 位作者 杨祖金 纪红兵 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1227-1234,共8页
Nineβ‐cyclodextrin derivatives containing an amino group were synthesized via nucleophilic sub‐stitution from mono(6‐O‐p‐tolylsulfonyl)‐β‐cyclodextrin and used in asymmetric biomimetic Mi‐chael addition re... Nineβ‐cyclodextrin derivatives containing an amino group were synthesized via nucleophilic sub‐stitution from mono(6‐O‐p‐tolylsulfonyl)‐β‐cyclodextrin and used in asymmetric biomimetic Mi‐chael addition reactions in water at room temperature. The mechanism responsible for the moder‐ate activity and enantioselectivity of the β‐cyclodextrin derivatives was explored using nuclear magnetic resonance spectroscopy, namely 2D 1H rotating‐frame overhauser effect spectroscopy (ROESY), ultraviolet absorption spectroscopy, and quantum chemical calculations, which provide a useful technique for investigating the formation of inclusion complexes. The effects of the pH of the reaction medium, theβ‐cyclodextrin derivative dosage, the structure of the modifying amino group, and various substrates on the yield and enantioselectivity were investigated. The results indicated that these factors had an important effect on the enantiomeric excess (ee) in the reaction system. Experiments using a competitor for inclusion complex formation showed that a hydrophobic cavity is necessary for enantioselective Michael addition. A comparison of the reactions using 4‐nitro‐β‐nitrostyrene and 2‐nitro‐β‐nitrostyrene showed that steric hindrance improved the enan‐tioselectivity. This was verified by the optimized geometries obtained from quantum chemical cal‐culations. An ee of 71%was obtained in the asymmetric Michael addition of cyclohexanone and 2‐nitro‐β‐nitrostyrene, using (S)‐2‐aminomethylpyrrolidine‐modified β‐CD as the catalyst, in an aqueous buffer solution, i.e., CH3COONa‐HCl (pH 7.5). 展开更多
关键词 β-cyclodextrin MODIFICATION Enantioselective Michael addition Quantum chemistry calculation
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乙肝疫苗无、弱应答与B7-CD28及IL-12、IL-10的相关性 被引量:33
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作者 黄茵 陈智 +3 位作者 徐承槐 李敏伟 蔡玲斐 金建华 《免疫学杂志》 CAS CSCD 北大核心 2002年第6期452-455,共4页
目的 研究乙肝疫苗无、弱应答与B7 CD2 8分子及IL 1 2、IL 1 0的相关性。方法 分离并培养乙肝疫苗强应答和无、弱应答者PBMCs ,以PHA或rHBsAg刺激。用流式细胞术检测培养细胞CD80、CD86及CD2 8的表达 ;酶标法检测上清IL 1 2、IL 1 0... 目的 研究乙肝疫苗无、弱应答与B7 CD2 8分子及IL 1 2、IL 1 0的相关性。方法 分离并培养乙肝疫苗强应答和无、弱应答者PBMCs ,以PHA或rHBsAg刺激。用流式细胞术检测培养细胞CD80、CD86及CD2 8的表达 ;酶标法检测上清IL 1 2、IL 1 0的水平 ;MTT法检测细胞增殖反应。结果 rHBsAg刺激后 ,无、弱应答组与强应答组比较 ,CD80和CD86的表达率、IL 1 2和IL 1 0水平、细胞增殖反应均降低 ,差异显著 ;但CD4+、CD8+细胞CD2 8的表达率无显著差异。PHA刺激后 ,上述指标在2组之间均无显著差异。结论 乙肝疫苗无、弱应答者一般的细胞免疫功能正常。抗 HBs低下与CD80、CD86表达及IL 1 2、IL 1 0产生不足等有关 ,但无T细胞CD2 展开更多
关键词 免疫应答 流式细胞术 乙肝疫苗 B7-cd28 IL-12 IL-10 细胞培养
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HP-β-CD对不动杆菌降解高浓度硝基苯的影响 被引量:11
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作者 邵云 高士祥 +2 位作者 杨彬 蔡邦成 王连生 《环境科学学报》 CAS CSCD 北大核心 2004年第4期690-695,共6页
研究了在不动杆菌降解高浓度硝基苯的过程中添加羟丙基-β-环糊精(HP-β-CD)对细菌生长、硝基苯的去除及中间产物的转化的影响.利用乙酸酐直接将硝基苯的降解样品酰基化,通过GC-MS分析定性出降解中间产物2 氨基苯酚.在适宜降解菌生长的4... 研究了在不动杆菌降解高浓度硝基苯的过程中添加羟丙基-β-环糊精(HP-β-CD)对细菌生长、硝基苯的去除及中间产物的转化的影响.利用乙酸酐直接将硝基苯的降解样品酰基化,通过GC-MS分析定性出降解中间产物2 氨基苯酚.在适宜降解菌生长的400mg·L-1硝基苯初始浓度下,加入250和500mg·L-1HP-β-CD对生物量和硝基苯的降解基本无影响;当硝基苯初始浓度约为850mg·L-1时,加入HP-β-CD(>2000mg·L-1)显著促进了细菌的生长、硝基苯的降解和2-氨基苯酚的生物转化,并且促进程度与加入量成正比.这种促进主要是因为HP-β-CD的空腔对硝基苯和2-氨基苯酚的包合产生了脱毒的效果.当HP-β-CD的加入浓度分别为0,2000,4000mg·L-1时,降解菌对850mg·L-1硝基苯的降解都遵循一级反应动力学,降解速率常数由0 0077h-1分别增加到0 0089和0 0161h-1,当HP-β-CD的加入浓度为8000mg·L-1时,降解菌对850mg·L-1硝基苯的降解遵循零级反应动力学,其降解速率常数为16 1162mg·L-1·h-1. 展开更多
关键词 HP-β-cd 硝基苯 微生物 环糊精 2-氨基苯酚 有机污染物
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CD_(40)-CD_(40L)与动脉粥样硬化的研究进展 被引量:5
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作者 贾运乔 刘朝霞 +2 位作者 赵欢 侯桂英 司秋菊 《中国老年学杂志》 CAS CSCD 北大核心 2010年第18期2710-2712,共3页
关键词 CD40-cd40L 动脉粥样硬化 炎症
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壳聚糖-CdS复合膜制备及其对吡啶的传感特性 被引量:13
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作者 王姗 房喻 +3 位作者 张颖 王明珍 胡道道 廖奕坤 《物理化学学报》 SCIE CAS CSCD 北大核心 2003年第6期514-518,共5页
利用壳聚糖(CS)易于成膜的特点,模拟生物矿化,在有机物调制下通过异相成核生长制备了CS/CdS纳米颗粒复合膜.研究了成膜条件对膜的水热稳定性和发光性能的影响,以及CS/CdS纳米颗粒复合膜对水体中吡啶的响应特性.扫描电镜分析表明CS/CdS... 利用壳聚糖(CS)易于成膜的特点,模拟生物矿化,在有机物调制下通过异相成核生长制备了CS/CdS纳米颗粒复合膜.研究了成膜条件对膜的水热稳定性和发光性能的影响,以及CS/CdS纳米颗粒复合膜对水体中吡啶的响应特性.扫描电镜分析表明CS/CdS纳米颗粒复合膜均匀性好,CdS以物理掺杂方式均匀分布于CS薄膜中,CdS颗粒尺寸在70nm左右.但薄膜荧光光谱位置和形状表明实际发光的CdS簇集体直径小于20nm.由此推测电镜观察到的CdS颗粒可能是由许多CdS小颗粒聚集而成,小颗粒之间因有机物的存在而相互隔离.CS/CdS纳米颗粒复合膜的荧光发射对水体中吡啶的存在十分敏感,微量吡啶的存在会引起薄膜荧光发射急剧增强.除铜和碘离子外,水体系中其他常见离子对薄膜荧光发射没有显著影响,预期CS/CdS纳米颗粒复合薄膜有可能发展成为一种重要的水体系吡啶测定专用传感薄膜材料. 展开更多
关键词 硫化铜 壳聚糖 荧光 纳米复合材料 薄膜 壳聚糖-cdS复合膜 制备 吡啶 传感特性
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EDTA、β-CD对唐古特白刺果实红色素稳定性的影响 被引量:5
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作者 张勇 李彩霞 +3 位作者 李鹏 曹洋 裴生美 陈年来 《食品科学》 EI CAS CSCD 北大核心 2007年第6期51-55,共5页
研究了EDTA和β-CD对唐古特白刺果实红色素稳定性的影响。结果表明:Fe3+对唐古特白刺果实红色素有明显的不良影响;加入EDTA、β-CD不仅可减缓唐古特白刺果实红色素的褪色速度,还可有效地抑制色素因Fe3+而对其产生的影响。实验结果还表明... 研究了EDTA和β-CD对唐古特白刺果实红色素稳定性的影响。结果表明:Fe3+对唐古特白刺果实红色素有明显的不良影响;加入EDTA、β-CD不仅可减缓唐古特白刺果实红色素的褪色速度,还可有效地抑制色素因Fe3+而对其产生的影响。实验结果还表明:EDTA对含Fe3+色素的护色作用均优于β-CD,增强了色素的稳定性,使之扩大了应用范围,提高使用价值。 展开更多
关键词 唐古特白刺果实 红色素 Fe^(3+) 稳定性 EDTA β-cd
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壳聚糖-CdS复合纳米粒子对甲基橙的光催化降解作用 被引量:15
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作者 侯进 陈国华 孟显丽 《材料科学与工艺》 EI CAS CSCD 北大核心 2008年第1期54-57,共4页
用反相微乳液法制备了壳聚糖-CdS复合纳米粒子,并考察了复合纳米粒子用量、光照条件和溶液pH值等因素对光催化降解甲基橙的影响.结果表明:在100 mL质量浓度为20 mg/L的甲基橙溶液中加入0.30 g复合纳米粒子,可以达到较好的光催化降解效果... 用反相微乳液法制备了壳聚糖-CdS复合纳米粒子,并考察了复合纳米粒子用量、光照条件和溶液pH值等因素对光催化降解甲基橙的影响.结果表明:在100 mL质量浓度为20 mg/L的甲基橙溶液中加入0.30 g复合纳米粒子,可以达到较好的光催化降解效果;甲基橙在光催化降解过程中最大吸收波长464 nm处的吸收峰迅速减弱,并最终消失,且在258 nm和455 nm处出现了新的吸收峰,说明甲基橙发生了降解;溶液pH值对光催化降解甲基橙有一定的影响,在弱酸性条件下降解效率较高;复合纳米粒子比普通CdS降解效率高,2 min时高出50%,400 min时高出21.3%.初步提出了复合纳米粒子光催化降解机理,复合纳米粒子的吸附作用是光催化降解作用的前置步骤. 展开更多
关键词 反相微乳液 壳聚糖-cdS复合纳米粒子 甲基橙 光催化降解 降解机理
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