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Non-Fusion and Fusion Expression of β-Galactosidase from Lactobacillus bulgaricus in Lactococcus lactis

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Biomedical and Environmental Sciences 2008年第5期21卷 389-397页

作者： CHUAN WANG CHAO-wu ZHANC HENG-CHUAN LIU QIAN YU AND XIAO-FANG pei Department of Medical Technology West China School of Public Health Sichuan University Chengdu 610041 Sichuan China

Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Loctobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate （27.1%） was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a host-related weak secretion signal peptide gene within the structure gene of Lb. bulgaricus β-galac

关键词： β-galactosidase Lactococcus lactis Lactose intolerance Protein expression Protein secretion.

1986—2022年河南省夏棉品种遗传改良成效

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河北农业科学 2024年第1期28卷 81-85页

作者：李武薄晓培赵付安吕淑平聂利红王红卫杨晓杰河南省农业科学院经济作物研究所河南郑州450002

本研究目的是为河南省夏棉遗传改良提供理论依据。以1986—2022年河南省审定的43个夏棉品种为试验材料,对其早熟性、产量、品质、抗病性等方面的遗传改良成效进行分析。结果表明:河南省夏棉品种的早熟性、产量、纤维品质遗传改良成效显... 详细信息

本研究目的是为河南省夏棉遗传改良提供理论依据。以1986—2022年河南省审定的43个夏棉品种为试验材料,对其早熟性、产量、品质、抗病性等方面的遗传改良成效进行分析。结果表明:河南省夏棉品种的早熟性、产量、纤维品质遗传改良成效显著。其中,子棉、皮棉、霜前皮棉产量每个时期分别以142.110、70.119和70.121 kg/hm^(2)的速度递增,同时生育期缩短4~15 d,现有品种产量的增长主要是通过提高单株铃数和衣分来实现的;纤维长度和断裂比强度每个时期分别以0.083 mm和0.407 cN/tex的平均速度递增,遗传改良效果显著;但马克隆值逐渐变大,纤维变粗趋势明显。枯萎病、黄萎病指数每个时期分别以1.015和2.233的平均速度递增,需进一步加强枯、黄萎病的抗性育种。

关键词：夏棉品种遗传改良产量品质抗病性

Perennial aneuploidy as a potential material for gene introgression between maize and Zea perennis

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Journal of Integrative Agriculture 2015年第5期14卷 839-846页

作者： FU Jie YANG Xiu-yan CHENG Ming-jun L Gui-hua WANG pei wu Yuan-qi ZHENG Ming-min ZHOU Shu-feng RONG Ting-zhao TANG Qi-lin Maize Research Institute Sichuan Agricultural University

Hybridization,which allows for gene flow between crops,is difficult between maize and Zea *** this study,we aim to initiate and study gene flow between maize and *** via a special aneuploid plant（MDT） derived from an interspecific hybrid of the two *** chromosome constitution and morphological characters of MDT as well as certain backcross progenies were *** from genomic in situ hybridization（GISH） indicate that aneuploid MDT consisted of nine maize chromosomes and 30 *** *** backcross progenies of MDTxmaize displayed significant diversity of vegetative and ear morphology;several unusual plants with specific chromosome constitution were founded in its *** special perennial progeny with several maize chromosomes were obtained by backcrossing MDT with ***,and the first whole chromosome introgression from maize to *** was detected in this *** this novel material and method,a number of maize-tetraploid teosinte addition or substitution lines can be generated for further study,which has great significance to maize and *** genetic research,especially for promoting introgression and transferring desirable traits.

关键词： chromosomes maize fertility pollen parental vegetative displayed tetraploid constitution sterility

耐低温超低压缩永久变形三元乙丙橡胶的配方设计

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橡胶科技 2024年第1期22卷 15-19页

作者：苏春义丁业乾杨春何培柯玉超田友峰章维国祝磊吴晨安徽中鼎密封件股份有限公司安徽宁国242300

研究由乙烯、丁烯和亚乙基降冰片烯为单体,茂金属催化合成的新型三元乙丙橡胶(EBT EPDM)和通用三元乙丙橡胶(EPDM)的耐低温性能以及炭黑种类对EBT EPDM胶料耐低温性能的影响。结果表明:与EPDM胶料相比,EBT EPDM胶料的t_(10)和t_(90)均缩... 详细信息

研究由乙烯、丁烯和亚乙基降冰片烯为单体,茂金属催化合成的新型三元乙丙橡胶(EBT EPDM)和通用三元乙丙橡胶(EPDM)的耐低温性能以及炭黑种类对EBT EPDM胶料耐低温性能的影响。结果表明:与EPDM胶料相比,EBT EPDM胶料的t_(10)和t_(90)均缩短,F_(max)-FL增大;EBT EPDM硫化胶在低温条件(-40℃×72 h)下的压缩永久变形减小71.5%,脆性温度降低37.7%,低温回缩温度TR10最低,低温弯曲后表面未出现裂纹,耐低温性能优异;随着炭黑粒径的增大,EBT EPDM硫化胶的低温压缩永久变形减小,脆性温度降低;在相同低温条件下,EBT EPDM硫化胶的压缩永久变形与硅橡胶硫化胶相近,但EBT EPDM价格远低于硅橡胶,可拓宽其在低温密封领域的应用。

关键词：三元乙丙橡胶压缩永久变形脆性温度低温回缩试验炭黑

排石颗粒联合微创手术治疗泌尿系统结石的临床观察

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中国社区医师 2017年第18期33卷 87-87,89页

作者：余学江吴培郑晨星仝墨泽合肥市第二人民医院泌尿外科 230000

目的:探讨排石颗粒联合微创手术治疗泌尿系统结石的效果。方法:收治泌尿系统结石患者200例,分为对照组和观察组。观察组采用排石颗粒联合微创手术治疗,对照组采用微创手术治疗,比较两组治疗效果。结果:治疗后,观察组治疗总有效率显著高... 详细信息

目的:探讨排石颗粒联合微创手术治疗泌尿系统结石的效果。方法:收治泌尿系统结石患者200例,分为对照组和观察组。观察组采用排石颗粒联合微创手术治疗,对照组采用微创手术治疗,比较两组治疗效果。结果:治疗后,观察组治疗总有效率显著高于对照组,且尿红细胞数显著低于对照组和治疗前(P<0.05)。结论:排石颗粒联合微创手术治疗泌尿系统结石的效果显著。

关键词：微创手术排石颗粒泌尿结石

Tissue-engineered composite scaffold of poly(lactide-co-glycolide) and hydroxyapatite nanoparticles seeded with autologous mesenchymal stem cells for bone regeneration

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第11期18卷 963-976页

作者： Bing ZHANG pei-biao ZHANG Zong-liang WANG Zhong-wen LYU Han wu Department of Clinical Laboratory Second Hospital of Jilin UniversityChangchun 130041China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Radiology China-Japan Union Hospital of Jilin UniversityChangchun 130033China Department of Orthopedics China-Japan Union Hospital of Jilin UniversityChangchun 130033China

Objective： A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapaUte （g-HA）/ poly（lactide-co-glycolide）（PLGA） carried with autologous mesenchymal stem cells （MSCs） and bone morphogenetic protein-2 （BMP-2） was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated. Methods： A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were ob- served by intramuscular implantation, as well as the repair of the critical radius defects in rabbits. Results： After eight weeks post-surgery, scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDX） revealed that g-HNPLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HNPLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HNPLGA at 2-8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HNPLGA, while only fibrous tissues formed in PLGA. Conclusions： The incorporation of g-HA mainly im- proved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone for- mation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.

关键词： Nanocomposite Surface modification Bone marrow mesenchymal stem cells Biomineralization Bone repair

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基于Burg算法的短序列谱估计研究

西安电子科技大学学报 2005年第5期32卷 724-728页

作者：罗丰段沛沛吴顺君西安电子科技大学雷达信号处理重点实验室陕西西安710071

在频域对采集数据进行了分析,提出了一种基于修正伯格算法的短序列谱估计方法.该方法在阶数估计时引入收敛因子,从而更为有效地估计了阶数,同时未直接采用伯格算法计算反射系数,而是先求得二阶预测误差系数,再求出一阶反射系数,并最终... 详细信息

在频域对采集数据进行了分析,提出了一种基于修正伯格算法的短序列谱估计方法.该方法在阶数估计时引入收敛因子,从而更为有效地估计了阶数,同时未直接采用伯格算法计算反射系数,而是先求得二阶预测误差系数,再求出一阶反射系数,并最终求得高阶系数完成谱估计.这种算法减小了谱偏,提高了分辨率.

关键词：功率谱估计最大熵方法伯格算法数字信号源

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草铵膦原药pH测量结果不确定度评估

山东化工 2021年第10期50卷 98-98,104页

作者：王广友林波吴培韩金涛山东省农药科学研究院山东省化学农药重点实验室山东济南250033

应用测量不确定度评定与表达的理论,以测定pH为例,分析了各种不确定度分量的来源并加以评定,计算合成不确定度及扩展不确定度,得出pH测量不确定度表达式,为实验室质量管理和控制提供科学依据。

关键词： pH值不确定度草铵膦

Automatic Matching of Multi-scale Road Networks under the Constraints of Smaller Scale Road Meshes

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Journal of Geodesy and Geoinformation Science 2019年第4期2卷 73-83页

作者： Hongxing pei Renjian ZHAI Fang wu Jinghan LI Xianyong GONG Zheng wu Center of TH-Satellite of China Beijing 100081China Institute of Geospatial Information Information Engineering UniversityZhengzhou 450000China

In this paper,we propose a new method to achieve automatic matching of multi-scale roads under the constraints of smaller scale *** matching process is:Firstly,meshes are extracted from two different scales road ***,several basic meshes in the larger scale road network will be merged into a composite one which is matched with one mesh in the smaller scale road network,to complete the N∶1(N>1)and 1∶1 ***,meshes of the two different scale road data with M∶N(M>1,N>1)matching relationships will be ***,roads will be classified into two categories under the constraints of meshes:mesh boundary roads and mesh internal roads,and then matchings between the two scales meshes will be carried out within their own categories according to the matching *** results show that roads of different scales will be more precisely matched using the proposed method.

关键词： multi-scale matching road networks matching road meshes