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Purification and Characterization of β-Glucosidase from a Newly Isolated Strain Tolypocladium cylindrosporum Syzx4

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Chemical Research in Chinese Universities 2011年第4期27卷 557-561页

作者： ZHANG Yi-bo YUAN Li-jia CHEN Zhao-jie FU lu lu jia-hui MENG Qing-fan HE Huan YU Xiao-xiao LIN Feng TENG Li-rong Key Laboratory for Molecular Enzymology ＆ Engineering Ministry of Education College of Life Science Jilin University Changchun 130012 P. R. China Department of Endocrinology Chian-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

A higher β-glucosidase-producing strain was isolated and identified as Tolypocladium cylindrosporum syzx4 based on its morphology and internal transcribed spacer（ITS） rDNA gene *** present study is to ferment,purify and characterize a β-glucosidase from *** *** enzyme was purified to homogeneity by sulfate precipitataion,diethylaminoethyl cellulose anion exchange chromatography and Sephadex G-100 gel filtration with a 9.47-fold increase in specific activity and a recovery of 12.27%.The molecular weight（Mw） of the β-glucosidase was estimated to be 58600 by SDS-PAGE,which is much lower than that of the enzyme from other *** β-glucosidase shows high activity over a wide range of temperature from 35℃ to 70℃ and the optimum pH is approximately *** the kinetic parameters Km（0.85 mmol/L） and vmax[85.23 mmol/（L·s）] of the β-glucosidase were studied,respectively with high affinity p-nitrophenyl-β-D-glucopyranoside（p-NPG） as the substrate,inhibition constant Ki（39.5 mmol/L） with the tolerance of *** β-glucosidases have been purified and characterized from several other sources,*** β-glucosidase with the unique optimal pH and higher tolerance of glucose distinguished from others makes the β-glucosidase a potential application in simultaneous saccharification and fermentation（SSF）.

关键词： β-Glucosidase Purification Characterization Thermoacidophilic Tolypocladium cylindrosporum syzx4

Extraction, Purification and Anti-tumor Activity of Polysaccharide from Mycelium of Mutant Cordyceps Militaris

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Chemical Research in Chinese Universities 2010年第5期26卷 798-802页

作者： ZHANG Ai-li lu jia-hui ZHANG Na ZHENG Dan ZHANG Gui-rong TENG Li-rong College of Life Science Jilin University Changchun 130012 P R. China

A water-soluble polysaccharide（named MCMP） was isolated from the mycelium with high yield mutation Cordyceps militaris by hot-water extraction, deproteinization by sevage, alcohol precipitation, anion-exchange and gel filtration chromatography CL-6B. The polysaccharide contained mannose, rhamnose, galactose and glucose in a molar ratio of 59.36：1：8.31：39.50, of which the average molecular weight is 8100. In our research, Hep-G2 cells, Hela cells and mesangial cells were chosen to determine the anti-tumor activity of the polysaccharide. The results of MTT assay show that polysaccharides of the mutant strain presented inhibitory activity on the cells proliferation after 48 h incubation.

关键词： Cordyceps militaris Polysaccharide Anti-tumor

Optimization of Fermentation Medium for Epothilones Production with Sequential Statistical Approach

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Chemical Research in Chinese Universities 2010年第1期26卷 86-91页

作者： MENG Fan-xin LI You-xin GUO Wei-liang lu jia-hui DU Lin-na TENG Li-rong College of Life Science Jilin University Changchun 130012 P. R. China

A sequential statistical approach was applied to optimizing the fermentation medium of epothilones（Epos） production by means of a mutant which was obtained by treating polyangium cellulosum ATCC 15384 with nitrite and ultraviolet. The effects of different carbon sources and nitrogen sources on the fermentation medium were tested, and the suitable ones were selected. Then a uniform design was employed to design the experiments. A linear model was developed for identifying the significant components in fermentation medium, while a third degree polynomial model was used for studying the relationship between the concentration of the components in fermentation medium and the yield of Epos（YEPs）. A pattern search method was used for searching the optimum fermentation medium in the test space, which was as follows（g/L）： potassium nitrate 8.00, soybean peptone 17.60, potassium hydrogen phos- phate 1.00, beef extraction 6.46, yeast extraction 1.00, calcium chloride 0.25, sodium chloride 1.00 and ferric chloride 0.02. The optimum fermentation medium was expected to result in a yield of Epos（YEPs） of 2.48 mg/L. The validation experiments with the optimum medium were performed in triplicate and the average yield of Epos was 2.45 mg/L which was 7.78 times higher than that of Epos prepared without optimization.

关键词： Statistical approach Epothilones Uniform design Optimization of fermentation medium

A comprehensive evaluation of factors affecting the accuracy of pig genotype imputation using a single or multi-breed reference population

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Journal of Integrative Agriculture 2022年第2期21卷 486-495页

作者： ZHANG Kai-li PENG Xia ZHANG Sai-xian ZHAN hui-wen lu jia-hui XIE Sheng-song ZHAO Shu-hong LI Xin-yun MA Yun-long Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionMinistry of Education/Key Laboratory of Swine Genetics and BreedingMinistry of Agriculture and Rural Affairs/College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

Genotype imputation has become an indispensable part of genomic data analysis. In recent years, imputation based on a multi-breed reference population has received more attention, but the relevant studies are scarce in pigs. In this study, we used the Illumina Porcine SNP50 Bead Chip to investigate the variations of imputation accuracy with various influencing factors and compared the imputation performance of four commonly used imputation software programs. The results indicated that imputation accuracy increased as either the validation population marker density, reference population sample size, or minor allele frequency(MAF) increased. However, the imputation accuracy would have a certain extent of decrease when the pig reference population was a mixed group of multiple breeds or lines. Considering both imputation accuracy and running time, Beagle 4.1 and FImpute are excellent choices among the four software packages tested. This work visually presents the impacts of these influencing factors on imputation and provides a reference for formulating reasonable imputation strategies in actual pig breeding.

关键词： genotype imputation multi-breed reference population imputation accuracy

First-order Derivative Spectrophotometry for the Determination of Vitamin C in Medicament

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Chemical Research in Chinese Universities 2008年第1期24卷 29-31页

作者： MENG Qing-fan TENG Le-sheng jiaNG Chao-jun An Jin-shuang LI Lei lu jia-hui TENG Li-rong College of Life Science Jilin University Changchun 130012 P. R. China

A novel method for the determination of vitamin C（Vc） is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-order derivative spectrum were obtained from the original spectrum. The values of derivative selected at 995 nm were used for determination. It was proved that Vc could quickly react with Folin-Ciocalteau reagent within 5 min and the product was quite stable for a long time. The conditions required for this method is not very complicated, its precision and accuracy are similar to those of the iodometric titration described in Chinese Pharmacopoeia, and the limit of detection is 0.312 μg/mL. The determination of the results of vitamin C tablet, pill, and injection demonstrates that this method has wide pharmaceutical applications.

关键词： First-order derivative spectroscopy Vitamin C determination Folin-Ciocalteau regent

Application of Near Infrared Diffuse Reflectance Spectroscopy with Radial Basis Function Neural Network to Determination of Rifampincin Isoniazid and Pyrazinamide Tablets

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Chemical Research in Chinese Universities 2007年第5期23卷 518-523页

作者： DU Lin-na WU Li-hang lu jia-hui GUO Wei-liang MENG Qing-fan jiaNG Chao-jun SHEN Si-le TENG Li-rong College of Life Science College of Animal Science and Veterinary Medicine College of Chemistry Jilin University Changchun 130012 P. R. China

Partial least squares（PLS）,back-propagation neural network（BPNN）and radial basis function neural network（RBFNN）were respectively used for estalishing quantative analysis models with near infrared（NIR）diffuse reflectance spectra for determining the contents of rifampincin（RMP）,isoniazid（INH）and pyrazinamide（PZA）in rifampicin isoniazid and pyrazinamide ***-Golay smoothing,first derivative,second derivative,fast Fourier transform（FFT）and standard normal variate（SNV）transformation methods were applied to pretreating raw NIR diffuse reflectance *** raw and pretreated spectra were divided into several regions,depending on the average spectrum and RSD *** component analysis（PCA）method was used for analyzing the raw and pretreated spectra in different regions in order to reduce the dimensions of input *** optimum spectral regions and the models＇ parameters were chosen by comparing the root mean square error of cross-validation（RMSECV）values which were obtained by leave-one-out cross-validation *** RMSECV values of the RBFNN models for determining the contents of RMP,INH and PZA were 0.00288,0.00226 and 0.00341,*** these models for predicting the contents of INH,RMP and PZA in prediction set,the RMSEP values were 0.00266,0.00227 and 0.00411,*** results are better than those obtained from PLS models and BPNN *** additional advantages of fast calculation speed and less dependence on the initial conditions,RBFNN is a suitable tool to model complex systems.

关键词： Rifampicin isoniazid and pyrazinamide tablets NIR diffuse reflectance spectroscopy Partial least square Back-propagation neural network Radial basis function neural network

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骨髓增生异常综合征发病机制研究进展

中国实验血液学杂志 2015年第6期23卷 1800-1807页

作者：许鸣陆嘉惠上海中医药大学附属岳阳中西医结合医院血液科上海200437 桐乡市第一人民医院中医科浙江桐乡314500 上海中医药大学附属市中医院血液科上海200071

骨髓增生异常综合征是一种克隆性骨髓干细胞异常的疾病,以无效造血和血细胞减少为临床特征。作为血液病学中信息度较低的一组"灰色病",随着近年来研究工作的不断深入,对其发病机制的探讨从分子遗传学、免疫表型特征转移到表观遗传学和... 详细信息

骨髓增生异常综合征是一种克隆性骨髓干细胞异常的疾病,以无效造血和血细胞减少为临床特征。作为血液病学中信息度较低的一组"灰色病",随着近年来研究工作的不断深入,对其发病机制的探讨从分子遗传学、免疫表型特征转移到表观遗传学和微环境等方面。然而,目前对MDS的发病机制仍然无明确的定论,通常应用的分子遗传学、免疫表型的研究已经不能满足MDS的实验和临床应用。目前针对造血干细胞、细胞因子、表观遗传等方面的研究更为深入,而且成果丰硕,相应的靶向药物如去甲基化药物氮杂胞苷和地西他滨等已经在MDS临床应用并已取得了令人满意的疗效。本文就近年来有关MDS发病机制中的造血干细胞、细胞因子、表观遗传改变等方面的研究进展进行综述,以便优化对MDS疾病进展的监控和指导其临床用药策略等。

关键词：骨髓增生异常综合征发病机制造血微环境表观遗传改变

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai jian hui jia Yu Wang Chun Cheng Yang Qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

电信服务业员工的情绪劳动与生活满意度——心理解脱的调节作用

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软科学 2012年第8期26卷 98-103页

作者：龚会时勘卢嘉辉中山大学管理学院广州510275 中国科学院研究生院管理学院北京100190

通过对332名电信营业厅服务岗位员工进行问卷调查,探讨员工工作中的心理解脱在情绪劳动与倦怠、情绪劳动与生活满意度的关系,以及在他们关系中的调节作用。结果发现,心理解脱不仅调节表层动作对生活满意度的负作用,而且调节倦怠对生活... 详细信息

通过对332名电信营业厅服务岗位员工进行问卷调查,探讨员工工作中的心理解脱在情绪劳动与倦怠、情绪劳动与生活满意度的关系,以及在他们关系中的调节作用。结果发现,心理解脱不仅调节表层动作对生活满意度的负作用,而且调节倦怠对生活满意度的预测作用。当员工在下班之后,经历高的心理解脱时,表层动作和倦怠对生活满意度的负面影响作用将会降低。研究结果有助于解释努力-恢复理论中,工作压力可以通过远离工作任务的方式,重新获得心理资源,促进这些因素在家庭界面的积极作用,提高个人幸福感和心理健康水平。

关键词：表层动作深层动作倦怠心理解脱生活满意度