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鸭肥胖基因的分子克隆、序列分析及原核表达

畜牧兽医学报 2005年第7期36卷 641-644页

作者：戴汉川龙良启华中农业大学水产学院淡水增养殖生物学重点实验室武汉430070

根据人、小鼠、猪等动物的肥胖基因编码区序列的保守性设计1对引物,利用RTPCR技术扩增出鸭肥胖基因的cDNA编码序列,将PCR产物插入pGEMT载体,经PCR和双酶切鉴定正确后进行序列测定,分析表明该cDNA序列由438个核苷酸组成,编码146个氨基酸... 详细信息

根据人、小鼠、猪等动物的肥胖基因编码区序列的保守性设计1对引物,利用RTPCR技术扩增出鸭肥胖基因的cDNA编码序列,将PCR产物插入pGEMT载体,经PCR和双酶切鉴定正确后进行序列测定,分析表明该cDNA序列由438个核苷酸组成,编码146个氨基酸组成的多肽,鸭与人、猪、小鼠、大鼠的核苷酸相似性分别为83%、84%、98%、94%;氨基酸的相似性分别为86%、83%、99%、96%。为了研究鸭肥胖基因体外表达的特点,构建了原核表达载体pET28aYa,在大肠杆菌中进行了诱导表达。结果表明,鸭肥胖基因在大肠杆菌中进行了高效特异性融合表达,融合蛋白分子量约为20ku,其中16ku为鸭肥胖基因表达的蛋白质,经薄层扫描分析,目的蛋白约占菌体总蛋白的30%。鸭肥胖基因的克隆和表达研究,为进一步研究鸭leptin的功能与应用奠定了基础。

关键词：鸭 ob基因基因表达 leptin

鲤鱼肥胖基因的分子克隆及在大肠杆菌中的表达

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动物学报 2005年第1期51卷 95-100页

作者：戴汉川龙良启丁光华中农业大学水产学院淡水增养殖生物学重点实验室武汉430070 云南农业大学动物科技学院昆明520001

为了研究鲤鱼肥胖基因的结构特点和体外表达产物的生物学活性 ,利用RT PCR技术从鲤鱼肠系膜脂肪组织中扩增出鲤鱼肥胖基因的cDNA编码序列 ,分析表明该cDNA序列由 4 38个核苷酸组成 ,编码 14 6个氨基酸组成的多肽 ,鲤鱼肥胖基因与人、猪... 详细信息

为了研究鲤鱼肥胖基因的结构特点和体外表达产物的生物学活性 ,利用RT PCR技术从鲤鱼肠系膜脂肪组织中扩增出鲤鱼肥胖基因的cDNA编码序列 ,分析表明该cDNA序列由 4 38个核苷酸组成 ,编码 14 6个氨基酸组成的多肽 ,鲤鱼肥胖基因与人、猪、鼠的相比 ,核苷酸同源性分别为 :84 %、 86 %、 95 % ;氨基酸的同源性分别为 84 %、 82 %、 96 %。构建了原核表达载体 pET 2 8a li,利用IPTG在大肠杆菌中进行了诱导表达 ,并对表达产物进行了初步纯化和生物活性检测 ,结果表明 ,鲤鱼肥胖基因在大肠杆菌中进行了高效特异性融合表达 ,融合蛋白质分子量约为 2 0kD ,经薄层扫描分析 ,目的蛋白占菌体总蛋白的 2 0 3%。表达产物经过纯化和复性能够明显抑制小鼠的摄食和生长。

关键词：肥胖基因生物学活性表达产物大肠杆菌 RT—PCR技术肠系膜核苷酸鲤鱼同源性利用

Asymmetric Synthesis of Perseal B and Viriolin

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有机化学 2004年第Z1期24卷 184-页

作者： XIA,Ya-Mu WANG,Xiao-long liang,qi-Ren CAO,Xiao-Ping PAN,Xin-Fu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

　　Perseal B (1) from the leaves of Persea obovatifolia, and viriolin (2) from the leaves of Virola surinamensis belong to 8-O-4' lignan. They show activity against leishmaniasis, a tropical disease transmitted by mo... 详细信息

关键词： belong to

基于ASHRAE晴空模型的日照作用下钢构件的温度场分析

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建筑钢结构进展 2012年第5期14卷 35-43页

作者：刘树堂龙期亮广州大学土木工程学院广州510006

分析钢结构温度效应和确定施工合拢温度关键在于确定温度场的分布。在日照下,由于钢构件的温度场分布非常复杂和不均匀,而难以确定。基于ASHRAE晴空模型,采用ANSYS的APDL语言对箱型钢构件在夏至日日间的温度场进行了数值模拟,模拟中考... 详细信息

分析钢结构温度效应和确定施工合拢温度关键在于确定温度场的分布。在日照下,由于钢构件的温度场分布非常复杂和不均匀,而难以确定。基于ASHRAE晴空模型,采用ANSYS的APDL语言对箱型钢构件在夏至日日间的温度场进行了数值模拟,模拟中考虑了太阳辐射强度、对流换热系数、构件表面太阳辐射吸收系数等对构件温度场的影响。结果表明:夏至日构件最高温度高达78.411℃,最大升温高达44.803℃;太阳辐射强度、对流换热系数和构件表面太阳辐射吸收系数对日照下的箱型钢构件温度场的影响起主导作用。

关键词：太阳辐射强度箱型钢构件温度场 ASHRAE晴空模型

城市地下通道近距离穿越地面桥梁桩基施工方案研究

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建筑技术 2013年第11期44卷 1041-1042页

作者：亓龙亮中国神华海外开发投资有限公司北京100011

地下空间的充分利用已成为解决日益严重的现代城市交通拥堵问题的主要途径,而地下空间施工不可避免地危害到邻近地面建筑或交通构筑物的运营安全,须慎重制订其施工方案。结合北京某地下人行通道近距下穿地面高架桥桩施工,并考虑承台-群... 详细信息

地下空间的充分利用已成为解决日益严重的现代城市交通拥堵问题的主要途径,而地下空间施工不可避免地危害到邻近地面建筑或交通构筑物的运营安全,须慎重制订其施工方案。结合北京某地下人行通道近距下穿地面高架桥桩施工,并考虑承台-群桩-土之间复杂的相互作用,运用有限差分软件FLAC3D,计算分析了地下通道施工对邻近地面桩基的沉降和受力影响,制订了合理的施工方案。

关键词：地下工程近距离下穿桩基沉降施工方案

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微生物降解对人参自毒作用的缓解效应

中国中药杂志 2014年第15期39卷 2868-2872页

作者：李勇龙期良丁万隆赵东岳中国医学科学院北京协和医学院药用植物研究所北京100193 中国中医科学院中药资源中心道地药材国家重点实验室培育基地北京100700

连作障碍问题严重制约人参生产及土地资源的合理利用,自毒作用是导致连作障碍的关键因子之一。在前期筛选到人参自毒物质降解菌的基础上,研究采用平板培养法和常规生理生化方法测定人参种子萌发的生物学指标和保护性酶活性,以探究自毒... 详细信息

连作障碍问题严重制约人参生产及土地资源的合理利用,自毒作用是导致连作障碍的关键因子之一。在前期筛选到人参自毒物质降解菌的基础上,研究采用平板培养法和常规生理生化方法测定人参种子萌发的生物学指标和保护性酶活性,以探究自毒物质降解菌对人参自毒作用的缓解效果。研究发现,除棕榈酸外,自毒物质苯甲酸、邻苯二甲酸二异丁酯、丁二酸二异丁酯和2,2-(4-羟基苯基)丙烷降解液对人参种子生长的毒害作用得到显著缓解,与对照无显著差异。除苯甲酸外,其余自毒物质降解后人参SOD,POD,CAT酶活性均较降解前显著降低。研究结果表明,微生物降解是缓解自毒物质抑制人参种子萌发的有效途径,该发现将有助于人参连作障碍问题的解决。

关键词：人参自毒物质降解菌种子萌发酶活性

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： Yi Li Bei-qi Wang Xin-Yin Zhang Shi-Jie Wang Cong-Yi Li Hui-long Yang Ran-Ran Su Tong Liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding

MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei Ming longfu Chen Tianliang Song Moxi Yele Hao Zhang long Yang Gegen Sarula Benliang liang Luting Yan Guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang Yanlin Fu Peiyan long Xiao Gao Zhengwei Wang Zhizhong Guan Xiaolan qi Wei Hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK