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Enantio-selective preparation of (S)-1-phenylethanol by a novel marine GDSL lipase MT6 with reverse stereo-selectivity 被引量:4
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作者 邓盾 张云 +1 位作者 孙爱君 胡云峰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1966-1974,共9页
We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein... We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein,we have investigated the use of MT6 in stereo-selective biocatalysis through direct hydrolysis reactions.Notably,the stereo-selectivity of MT6 was also demonstrated to be opposite to that of other common lipases in hydrolysis reactions.Parameters,including temperature,organic co-solvents,pH,ionic strength,catalyst loading,substrate concentration,and reaction time,affecting the enzymatic resolution of racemic 1-phenylethyl acetate were further investigated,with the e.e.of the final(S)-l-Phenylethanol product and the conversion being 97%and 28.5%,respectively,after process optimization.The lengths of side chains of 1-phenylethyl esters greatly affected the stereo-selectivity and conversion during kinetic resolutions.MT6 is a novel marine microbial GDSL lipase exhibiting opposite stereo-selectivities than other common lipases in both trans-esterification reactions and hydrolysis reactions. 展开更多
关键词 GDSLlipase BIOCATALYSIS Kinetic resolution Direct hydrolysis (S)-1-Phenylethanol reverse stereo-selectivity
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Preparation and Characterization of Cathode Materials La_(0.7)Sr_(0.3-x)Ca_xCo_(0.9)Fe_(0.1)O_(3-δ) by Reverse Titration Co-Precipitation Method for ITSOFC 被引量:1
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作者 高文元 胡志强 +5 位作者 李长敏 唐乃岭 孙福禄 唐旭 魏蔷薇 孙永平 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期358-363,共6页
The precursors of La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF, x=0.05, 0.10, 0.15, 0.20) as the cathode materials for intermediate temperature solid oxide fuel cell (ITSOFC) were prepared by reverse titration co-precipitatio... The precursors of La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF, x=0.05, 0.10, 0.15, 0.20) as the cathode materials for intermediate temperature solid oxide fuel cell (ITSOFC) were prepared by reverse titration co-precipitation method with metal-nitrates as starting materials and mixed alkali (NaOH and Na2CO3) as a precipitating agent. The formation process of LSCCF from the precursors was monitored by TG-DSC, and the crystal structure and particles morphology of the precursors which were calcined at 600, 800, 1000 ℃ for 3 h were characterized using XRD, SEM technologies. Compared with the solid state reaction of constituent oxides, when the pH value of the precipitating solution was in the range of 9.1~9.5, the LSCCF powders from the precursors caclined at 800 ℃ for 3 h had high purity, homogeneous and single perovskite phase. The electrical conductivity of the LSCCF samples sintered at 1200 ℃ for 3 h, which was measured as a function of temperatures from 100 to 800 ℃ by DC four-probe method in air, decreased with x from 0.05 to 0.20. The value of electrical conductivity was almost equal because of Ca2+, Sr2+ co-dopant resulting in the 'mix effect' while x=0.10 or 0.15. The electrical conductivity of all doped samples was higher than 100 S·cm-1 at intermediate temperatures from 500 to 800 ℃, and there was good compatibility between the LSCCF cathode and Ce0.8Sm0.2O2 electrolyte. 展开更多
关键词 intermediate temperature solid oxide fuel cell La_(0.7)Sr_(0.3-x)Ca_xCo(1-y)Fe_yO_(3-δ) reverse titration co-precipitation property rare earths
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Differential interformational velocity analysis as an effective direct hydrocarbon indicator under velocity reversal conditions,an example from the anomalously high temperature and over-pressured DF1-1 Gas Field in the Yinggehai Basin,South China Sea
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作者 Zhu Hongtao Liu Keyu +2 位作者 Chen Kaiyuan Li Min Huang Shengbing 《Petroleum Science》 SCIE CAS CSCD 2009年第4期339-346,共8页
In the DF1-1 Gas Field in the Yinggehai Basin, South China Sea, the velocity-depth plot and velocity spectra show significant variations from a linear trend, exhibiting a distinct reversal phenomenon. Velocity paramet... In the DF1-1 Gas Field in the Yinggehai Basin, South China Sea, the velocity-depth plot and velocity spectra show significant variations from a linear trend, exhibiting a distinct reversal phenomenon. Velocity parameters derived from velocity spectral analysis of the seismic data and sonic logs indicate that the interval velocity reverses below 2,100 m (2.2 s two-way time (TWT)) in the DF1-1 Gas Field. Some direct hydrocarbon indicators (DHIs) models developed for the shallow strata cannot be simply applied to the moderately to deeply buried strata for direct exploration target recognition because the velocity reversal has caused the middle-deep gas reservoirs to exhibit a moderate or weak seismic amplitude. The hydrocarbon indicator method of “Differential Interformational Velocity Analysis (DIVA)” with the aid of other hydrocarbon indicating techniques was employed to effectively identify DHIs in the middle-deep strata under velocity inversion. The result has shown that the DIVA technique can be effectively used as a DHI in both the shallow and the middle-deep strata in the study area with the shallow strata characterized by Type I DIVA anomaly and the middle-deep strata characterized by the Type II DIVA anomaly. 展开更多
关键词 DF1-1 Gas Field velocity reversal direct hydrocarbon indicator differential interformational velocity analysis South China Sea
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Synthesis and biological evaluation of novel 1-aryl-5-iodo-6-benzyluracils as potent HIV-1 non-nucleoside reverse transcriptase inhibitors
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作者 王惟 李立 +5 位作者 刘畅 张亮 闫寒 张志丽 王孝伟 刘俊义 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第4期312-317,共6页
We have synthesized the novel compounds 1a-1i,which are a series of hybrid analogues to 6-benzyl-1-(benzyloxymethyl)- 5-iodouracil,a compound showing strong activity against HIV-1.We also evaluated the activity of t... We have synthesized the novel compounds 1a-1i,which are a series of hybrid analogues to 6-benzyl-1-(benzyloxymethyl)- 5-iodouracil,a compound showing strong activity against HIV-1.We also evaluated the activity of these compounds as the inhibitors of HIV-1 reverse transcriptase(HIV-1 RT),and they have demonstrated moderate activity. 展开更多
关键词 HIV-1 reverse transcriptase Non-nucleoside reverse transcriptase inhibitors l-[(2-Hydroxyethoxy)methyl]-6-phenylthiothymine
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The epigallocatechin gallate derivative Y_6 reverses drug resistance mediated by the ABCB1 transporter both in vitro and in vivo 被引量:4
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作者 Yan Wen Ruiqiang Zhao +10 位作者 Pranav Gupta Yingfang Fan Yunkai Zhang Zhenguang Huang Xiaohui Li Yuangang Su Lijuan Liao Yu-An Xie Donghua Yang Zhe-Sheng Chen Gang Liang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2019年第2期316-323,共8页
Previously, we reported that Y_6, a new epigallocatechin gallate derivative, is efficacious in reversing doxorubicin(DOX)–mediated resistance in hepatocellular carcinoma BEL-7404/DOX cells. In this study, we evaluate... Previously, we reported that Y_6, a new epigallocatechin gallate derivative, is efficacious in reversing doxorubicin(DOX)–mediated resistance in hepatocellular carcinoma BEL-7404/DOX cells. In this study, we evaluated the efficacy of Y_6 in reversing drug resistance both in vitro and in vivo by determining its effect on the adenosine triphosphate-binding cassette protein B1 transporter(ABCB1 or P-glycoprotein, P-gp). Our results showed that Y_6 significantly sensitized cells overexpressing the ABCB1 transporter to anticancer drugs that are ABCB1 substrates. Y_6 significantly stimulated the adenosine triphosphatase activity of ABCB1. Furthermore, Y_6 exhibited a higher docking score as compared with epigallocatechin gallate inside the transmembrane domain of ABCB1. In addition, in the nude mousetumor xenograft model, Y_6(110 mg/kg, intragastric administration), in combination with doxorubicin(2 mg/kg, intraperitoneal injection), significantly inhibited the growth of BEL-7404/DOX cell xenograft tumors, compared to equivalent epigallocatechin gallate. In conclusion, Y_6 significantly reversed ABCB1-mediated multidrug resistance and its mechanisms of action may result from its competitive inhibition of the ABCB1 drug efflux function. 展开更多
关键词 EPIGALLOCATECHIN gallate(EGCG) 5 3’ 4’ 3″ 4″ 5″-6-O-ethylEGCG(Y6) Drug RESISTANCE RESISTANCE reversAL ABCB1 P-gp
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“合谷刺与反合谷刺”治疗顽固性周围性面瘫32例 被引量:9
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作者 郑颖颖 郑健刚 《辽宁中医杂志》 CAS 2014年第2期338-339,共2页
目的:观察"合谷刺与反合谷刺"对顽固性周围性面瘫的疗效。方法:从临床工作中,收集病程>2个月的周围性面瘫,均采用"合谷刺与反合谷刺"法进行治疗。结果:经过8个疗程治疗后,治愈29例,占90.62%;显效2例,好转1例,无... 目的:观察"合谷刺与反合谷刺"对顽固性周围性面瘫的疗效。方法:从临床工作中,收集病程>2个月的周围性面瘫,均采用"合谷刺与反合谷刺"法进行治疗。结果:经过8个疗程治疗后,治愈29例,占90.62%;显效2例,好转1例,无效0例,总有效率为100%。结论:"合谷刺与反合谷刺"对顽固性周围性面瘫有良好疗效。 展开更多
关键词 合谷刺 反合谷刺 顽固性 面瘫
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Significance of combined detection of LunX mRNA and tumor markers in diagnosis of lung carcinoma 被引量:3
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作者 Hui Yu Xiuying Huang +4 位作者 Zhihua Zhu Yi Hu Wei Ou Lanjun Zhang Ningning Zhou 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第1期89-94,共6页
Objective:To evaluate the significance of combined detection of LunX mRNA,carcinoembryonic antigen (CEA),neuron-specific enolase (NSE),and cytokeratin 21-1 fragment (CYFRA21-1) in clinical diagnosis of lung car... Objective:To evaluate the significance of combined detection of LunX mRNA,carcinoembryonic antigen (CEA),neuron-specific enolase (NSE),and cytokeratin 21-1 fragment (CYFRA21-1) in clinical diagnosis of lung carcinoma.Methods:Based on the quantitative RT-PCR and chemiluminescence immunoassay,the expression levels of LunX mRNA,CEA,NSE,and CYFRA21-1 in 113 patients with lung carcinoma (case group) and 30 healthy participants (control group) were detected.Meantime,the sensitivity,specificity,and accuracy of the combination detection were also explored.Results:The positive rates of LunX mRNA in peripheral blood and CEA,NSE,and CYFRA21-1 in serum were significandy higher in case group than those in control group (x2=17.295,16.825,19.148,and 17.450; P<0.05).There was no statistical significance when positive rate of LunX mRNA was evaluated among different pathological types (x2=0.047,P>0.05).The positive rate of LunX mRNA in stage Ⅰ + Ⅱ,Ⅲ,and Ⅳ had a significandy increasing tendency (x2=10.565,32.462,P<0.05).The positive rate of CYFRA21-1 was highest in squamous carcinoma (78.5%),the positive rate of NSE was highest in small cell carcinoma (86.7%),and the positive rate of CEA wag highest in lung adenocarcinoma (80.4%).The sensitivity and accuracy of the combination detection were 91.1% and 88.1%,respectively.Conclusions:The combined detection of LunX mRNA and tumor markers (TMs) including CEA,NSE,and CYFRA21-1 in peripheral blood is helpful to increase the diagnostic accuracy of lmg cancer.Also,it can inform the pathological typing of lung carcinoma. 展开更多
关键词 Lung cancer reverse transcription-polymerase chain reaction LunX mRNA carcinoembryonic antigen (CEA) neuron-specific enolase (NSE) cytokeratin 21-1 fragment (CYFRA21-1
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Synthesis and anti-HIV activities of phorbol derivatives
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作者 HUANG Xiaolei TANG Chengrun +9 位作者 HUANG Xusheng YANG Yun LI Qirun MA Mengdi ZHAO Lei YANG Liumeng CUI Yadong ZHANG Zhenqing ZHENG Yongtang ZHANG Jian 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第2期146-160,共15页
In this study,37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated,building upon our previous synthesis of 51 phorbol derivatives.12-Para-electron-acceptor-trans-cinnamoyl-13-dec... In this study,37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated,building upon our previous synthesis of 51 phorbol derivatives.12-Para-electron-acceptor-trans-cinnamoyl-13-decanoyl phorbol derivatives stood out,demonstrating remarkable anti-HIV-1 activities and inhibitory effects on syncytia formation.These derivatives exhibited a higher safety index compared with the positive control drug.Among them,12-(trans-4-fluorocinnamoyl)-13-decanoyl phorbol,designated as compound 3c,exhibited the most potent anti-HIV-1 activity(EC_(50)2.9 nmol·L^(−1),CC50/EC_(50)11117.24)and significantly inhibited the formation of syncytium(EC_(50)7.0 nmol·L^(−1),CC50/EC_(50)4891.43).Moreover,compound 3c is hypothesized to act both as an HIV-1 entry inhibitor and as an HIV-1 reverse transcriptase inhibitor.Isothermal titration calorimetry and molecular docking studies indicated that compound 3c may also function as a natural activator of protein kinase C(PKC).Therefore,compound 3c emerges as a potential candidate for developing new anti-HIV drugs. 展开更多
关键词 Phorbol esters Anti-HIV-1 activity Syncytia formation 12-(Trans-4-fluorocinnamoyl)-13-decanoyl phorbol Safety index HIV-1 entry inhibitor HIV-1 reverse transcriptase inhibitor PKC activator
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