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一株四环素高效降解菌的分离及降解特性 被引量:14
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作者 吴学玲 吴晓燕 +3 位作者 李交昆 申丽 余润兰 曾伟民 《生物技术通报》 CAS CSCD 北大核心 2018年第5期172-178,共7页
四环素类抗生素在养殖业中广泛使用引起药物残留,给环境及人类健康带来了深远影响。从利用四环素类抗生素作为饲料添加剂的养猪厂底泥中,筛选获得一株能够高效降解四环素的细菌XY-1,经革兰氏染色、形态学观察、生理生化及16S rDNA序列... 四环素类抗生素在养殖业中广泛使用引起药物残留,给环境及人类健康带来了深远影响。从利用四环素类抗生素作为饲料添加剂的养猪厂底泥中,筛选获得一株能够高效降解四环素的细菌XY-1,经革兰氏染色、形态学观察、生理生化及16S rDNA序列分析等,确定该菌株属于拉乌尔菌属,命名为Raoultella sp.XY-1。采用高效液相色谱(HPLC)测定了菌株XY-1对四环素的降解能力,结果表明,该菌株最佳降解条件是温度为25℃,初始pH值为7.0,在此最佳条件下,XY-1在第8天时生长量最大且四环素降解率最高达到70.68%。对XY-1的四环素耐药基因进行了初步探究,首次在该菌株中检测到两种四环素耐药基因tet(D)和tet(E)。 展开更多
关键词 四环素降解菌 筛选及鉴定 降解特性 四环素耐药基因
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不同用量配伍当归芍药散对动物学习记忆功能及脑内NO的影响 被引量:7
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作者 刘红 zeng +2 位作者 Yu 曾宇 马世平 《中国临床药理学与治疗学》 CAS CSCD 2005年第9期974-977,共4页
目的:研究不同用量配伍当归芍药散对动物学习记忆功能及脑内神经化学物质NO的影响。方法:用避暗法和水迷宫法测定小鼠的学习记忆功能,脑内NO的测定参照试剂盒方法进行。结果:不同归芍比的当归芍药散对正常小鼠的学习记忆能力都有一定的... 目的:研究不同用量配伍当归芍药散对动物学习记忆功能及脑内神经化学物质NO的影响。方法:用避暗法和水迷宫法测定小鼠的学习记忆功能,脑内NO的测定参照试剂盒方法进行。结果:不同归芍比的当归芍药散对正常小鼠的学习记忆能力都有一定的促进作用,其中归芍比为15.4、11.34的组方能明显改善东莨菪碱所致小鼠被动回避障碍,明显延长小鼠潜伏期,减少错误次数;在改善小鼠空间辨别障碍方面,归芍比为11.34的当归芍药散能明显缩短利血平化小鼠水迷宫潜伏期,改善小鼠空间辨别障碍,其余各组方对正常小鼠水迷宫潜伏期影响不明显;而不同归芍比的当归芍药散能降低东莨菪碱所致的被动回避障碍小鼠脑内NO含量升高。结论:当归芍药散中归芍比为11.34时,既能明显改善小鼠被动回避障碍,又能明显改善小鼠空间辨别障碍,降低东莨菪碱所致的被动回避障碍小鼠脑内NO含量的升高,益智作用最佳。 展开更多
关键词 当归芍药散 配伍 学习 记忆功能 一氧化氮
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BIM技术在建筑设计阶段的正向设计应用探索 被引量:65
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作者 曾旭东 周鑫 +1 位作者 张磊 zeng 《西部人居环境学刊》 2019年第6期119-126,共8页
当前,BIM技术在建筑设计应用过程中普遍存在"翻模"现象,这种"翻模"方法没有在建筑设计阶段真正运用BIM技术,未能体现BIM技术在设计阶段的价值,实现BIM技术在建筑设计阶段的正向设计应用已迫在眉睫。根据建筑设计数... 当前,BIM技术在建筑设计应用过程中普遍存在"翻模"现象,这种"翻模"方法没有在建筑设计阶段真正运用BIM技术,未能体现BIM技术在设计阶段的价值,实现BIM技术在建筑设计阶段的正向设计应用已迫在眉睫。根据建筑设计数字化所具有的特性,在BIM技术本身所具有的核心功能下,以不同工程实例在建筑设计各个阶段中BIM技术的应用过程为基础,探索BIM技术在建筑设计阶段正向设计中的特点与发展方向,分别提出BIM技术在建筑方案设计、初步设计和施工图设计过程中的工作要点。 展开更多
关键词 BIM技术 正向设计 建筑设计
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铝电解废槽衬资源化利用技术进展 被引量:6
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作者 李雪莲 曾华 +1 位作者 徐芮 王丽 《矿冶》 CAS 2022年第3期50-58,共9页
铝电解废槽衬是铝电解工业产生的一种危险固体废弃物,含可溶的氟化物和氰化物,会对周围的环境造成危害。介绍了铝电解废槽衬的形成原因、废阴极炭块的综合回收利用工艺以及废耐火材料的无害化处理技术。总结了废槽衬中有害物质的存在形... 铝电解废槽衬是铝电解工业产生的一种危险固体废弃物,含可溶的氟化物和氰化物,会对周围的环境造成危害。介绍了铝电解废槽衬的形成原因、废阴极炭块的综合回收利用工艺以及废耐火材料的无害化处理技术。总结了废槽衬中有害物质的存在形式及分布位置,分析了电解铝过程中钠的渗透行为以及阴极炭块石墨化过程的机理及影响因素。 展开更多
关键词 废槽衬 固体废弃物 分离回收 无害化处理 石墨化
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英语拟声词的结构及其音韵特征 被引量:6
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作者 曾素琴 zeng Su-qin 《集美大学学报(哲学社会科学版)》 2001年第2期91-95,共5页
从英语语音规则制约的角度 ,在音节结构和构词方法两个方面对英语拟声词的结构特点进行了分析 ;
关键词 英语 拟声词 音节结构 构词方法 音韵特征 语音 韵律
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Therapeutic endoscopic retrograde cholangiopancreatography in a patient with situs inversus viscerum 被引量:4
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作者 Yi Hu +9 位作者 Hao zeng Xiao-Lin Pan Nong-Hua Lv Zhi-Jian Liu Yang Hu 《World Journal of Gastroenterology》 SCIE CAS 2015年第18期5744-5748,共5页
Situs inversus viscerum(SIV)is a rare congenitalcondition characterized by complete transposition of all viscera.This anatomical pathology makes endoscopic retrograde cholangiopancreatography(ERCP)technically difficul... Situs inversus viscerum(SIV)is a rare congenitalcondition characterized by complete transposition of all viscera.This anatomical pathology makes endoscopic retrograde cholangiopancreatography(ERCP)technically difficult.We report a new case of a 70-year-old Chinese male with total SIV who had obstructive jaundice.Magneticresonance cholangiopancreatography demonstrated a number of stones in the gallbladder and common bile duct(CBD).Therapeutic ERCP was performed to relieve biliary obstruction and remove the CBD stones.This procedure started with the patient in a supine position and the endoscopist at the left side of the table.When the papilla was maintained,the patient was repositioned to a prone position and standard endoscopic sphincterotomy and endoscopic papillary balloon dilatation procedures were conducted.ERCP was performed successfully and relevant complications did not occur in this patient.We also present a review of the literature published between 1985 and 2014in the Pub Med and EMBASE databases.There were eight published cases during this period,with one each from America,Finland,India,Italy,South Korea and Pakistan,and two from Spain.Our case is the first reported in China. 展开更多
关键词 Situs inversus ENDOSCOPIC RETROGRADE cholan-giopancreatography Common BILE duct ENDOSCOPIC SPHINCTEROTOMY ENDOSCOPIC PAPILLARY balloon DILATATION
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Isolation and characteristics of one marine psychrotrophic cellulase-generating bacterium Ar/w/b/75°/10/5 from Chuckchi Sea,Arctic 被引量:4
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作者 zeng Yinxin(曾胤新) +1 位作者 Chen Bo(陈波) 《Chinese Journal of Polar Science》 2002年第2期157-168,共12页
Microorganisms living in polar zones play an important part as the potential source of organic activity materials with low temperature characteristics in the bio-technological applications. A psychrotrophic bacterium ... Microorganisms living in polar zones play an important part as the potential source of organic activity materials with low temperature characteristics in the bio-technological applications. A psychrotrophic bacterium (strain Ar/w/b/75°/10/5) , producing cellulose at low temperatures during late-exponential and early-stationary phases of cell growth, was isolated from sea ice-covered surface water in Chuckchi Sea, Arctic. This bacterium, with rod cells, was Gram-negative, slightly halophilic. Colony growing on agar plate was in black. Optimum growth temperature was 15℃. No cell growth was observed at 351 or above. Optimum salt concentration for cell growth was between 2 and 3 % of sodium chloride in media. Maximal cellulase activity was detected at a temperature of 35℃ and pH8. Cellulase was irreversibly inactivated when incubated at 55℃ within 30 min. Enzyme can be kept stable at the temperature no higher than 25℃. Of special interest was that this bacterium produced various extracellular enzymes including cellulase, amylase, agar hydrolase and protease, at low or moderate temperature conditions, which is certainly of it potential value for applications. 展开更多
关键词 PSYCHROTROPHIC BACTERIUM CELLULASE Chuckchi Sea Arctic.
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谢桥煤矿1212(3)工作面运输巷沿空掘巷的研究与应用
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作者 曾锋 柯成名 +6 位作者 张敏 zeng Feng HE Cheng-ming ZHANG Min 《煤矿开采》 2005年第3期50-52,共3页
介绍了谢桥矿C13 1煤层沿空掘巷的支护方式和生产期间的治理经验。为“三软”煤层沿空掘巷的支护和生产期间的治理提供一定的依据。
关键词 采煤工作面 沿空掘巷 支护与治理 应用效果
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A facile preparation of hausmannite as a high-performance catalyst for toluene combustion 被引量:1
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作者 Qi Liu Gao Cheng +6 位作者 Ming Sun Weixiong Yu Xiaohong zeng Shichang Tang Yongfeng li Lin Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期392-401,共10页
Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic compounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn_(3)O_(4)(mMn_(3)O_(4))with... Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic compounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn_(3)O_(4)(mMn_(3)O_(4))without the use of templates or surfactants.In this method,KCl protects oxygen defects on the surface of fresh Mn_(3)O_(4) crystallites.m-Mn_(3)O_(4) shows higher ameliorative catalytic activity than bulk-Mn_(3)O_(4)(b-Mn_(3)O_(4)) and calcined-Mn_(3)O_(4)(c-Mn_(3)O_(4)),achieving toluene catalytic oxidation of T_(10) and T_(90)(the temperature at a conversion rate of about 10%and 90%)at 191℃and 230℃,respectively(WHSV=40,000 ml·g^(-1)·h^(-1)).Based on various characterizations,the prepared m-Mn_(3)O_(4)has large specific surface area and abundant oxygen defects,and thus can provide more surface active sites,which give it superior toluene combustion activity. 展开更多
关键词 CATALYSIS NANOMATERIALS Environment TOLUENE Solvents Mn_(3)O_(4)
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IMPROVEMENT OF HOT CORROSION RESISTANCE OF Ti_3Al INTERMETALLIC COMPOUND BY 被引量:1
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作者 zeng Chaoliu Zhang +2 位作者 Jianqing Wu, Weitao Zhu, Shenglong(Corrosion Science Laboratory Institute of Corrosion and Protection of Metals, Academia Sinica , Shenyang 110015) 《中国有色金属学会会刊:英文版》 CSCD 1995年第1期76-79,共4页
IMPROVEMENTOFHOTCORROSIONRESISTANCEOFTi_3AlINTERMETALLICCOMPOUNDBYSPUTTEREDNiCrAlYCOATINGZeng;ChaoliuZhang;J... IMPROVEMENTOFHOTCORROSIONRESISTANCEOFTi_3AlINTERMETALLICCOMPOUNDBYSPUTTEREDNiCrAlYCOATINGZeng;ChaoliuZhang;JianqingWu,;Weitao?.. 展开更多
关键词 INTERMETALLIC COMPOUNDS Ti3Al NICRALY coating hot corrosion
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从投资增量分析绿色建筑节能技术应用的意义
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作者 曾姗姗 zeng +3 位作者 Shanshan 赵玉兰 Zhao Yulan 《中国科技期刊数据库 工业A》 2016年第9期270-271,共2页
目前绿色建筑在我国已经进入全面推行的阶段,但由于对绿色建筑增量成本的认识不明,大大地制约了绿色建筑节能技术的应用,同时也影响了绿色建筑的发展。本文以实际绿色建筑工程为例对绿色建筑节能技术的应用和增量成本进行了分析,得出绿... 目前绿色建筑在我国已经进入全面推行的阶段,但由于对绿色建筑增量成本的认识不明,大大地制约了绿色建筑节能技术的应用,同时也影响了绿色建筑的发展。本文以实际绿色建筑工程为例对绿色建筑节能技术的应用和增量成本进行了分析,得出绿色建筑不一定是高成本,只要按照绿色建筑节能实施细则选用合理的绿色建筑节能技术,就会在增加少量成本的基础上收到高效的节能效果。 展开更多
关键词 绿色建筑节能技术 技术增量成本 低成本高收益
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The First Total Synthesis of 16-Hydroxygeranylgeraniol
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作者 Li zeng +4 位作者 PENG Tian Sheng MEI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第3期249-250,共2页
Facile synthesis of 16-hydroxygeranylgeranio 1, a naturally occurring alicyclic diterpene, by alkylation reaction of allylic iodide 3 with phenyl sulfone 4, is described.
关键词 Total synthesis 16-hydroxygeranylgeraniol diterpene.
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ISHIKAWA ITERATIVE PROCESS FOR CONSTRUCTING SOLUTIONS OF m-ACCRETIVE OPERATOR EQUATIONS
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作者 zeng Liu-chuan(曾六川) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期686-693,共8页
The convergence of the Ishikawa iteration sequences with errors for constructing solutions of m-accretive operator equations is characterized. Moreover, the error estimates of approximate solutions for locally Lipschi... The convergence of the Ishikawa iteration sequences with errors for constructing solutions of m-accretive operator equations is characterized. Moreover, the error estimates of approximate solutions for locally Lipschitzian and m-accretive operator equations are established. 展开更多
关键词 m-accretive operator Ishikawa iterative sequence uniformly smooth Banach space
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Wavelength Reusability of Failure Protection Based on Rerouting in Wavelength-routed Optical Networks
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作者 杨旭东 zeng +6 位作者 Qingji Wang Yun Liu Fengqing ZHU Xu 《High Technology Letters》 EI CAS 2004年第1期8-12,共5页
This paper investigates the wavelength efficiency of failure protection based on rerouting in wavelength-routed optical networks. In order to study the impacts of different traffic pattern over the efficiency, a param... This paper investigates the wavelength efficiency of failure protection based on rerouting in wavelength-routed optical networks. In order to study the impacts of different traffic pattern over the efficiency, a parameter, wavelength reusability ρ, is introduced as an evaluation criterion. Performance of different failure protection methods and the influence of different routing schemes over the performance are investigated. The routing and wavelength assignment problem involved in failure protection is formulated as integer linear programming problem, relevant heuristic optimization algorithms are also developed, numerical results are presented and discussed in detail. 展开更多
关键词 密集波长复用技术 故障保护 波长路径 光学网络 拥塞 最优化算法 线性程序 数据传输网
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Wavelength Assignment in WDM Optical Networks with Limited-range Wavelength Conversion
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作者 叶通 zeng +4 位作者 Qingji Zhu Guolong Yang Junjie 《High Technology Letters》 EI CAS 2004年第3期6-9,共4页
According to previous studies, limited range wavelength conversion (LWC) can improve the performance of optical network. In this paper, the effects of FWM (Four Wave Mixing) and XGM (Cross-Gain Modulation) conversion ... According to previous studies, limited range wavelength conversion (LWC) can improve the performance of optical network. In this paper, the effects of FWM (Four Wave Mixing) and XGM (Cross-Gain Modulation) conversion are both examined. It is found that the performance difference between LWC and full conversion becomes quite remarkable with the increase in numbers of wavelengths per-link. So in order to improve the performance of optical network with limited conversion in the case of large number of wavelengths, three simple dynamic wavelength assignment algorithms (LUWC, FUWC and WSM) are proposed. Simulation results show that the algorithms greatly reduce the blocking probabilities of networks with LWC. Moreover, the algorithms require no global information of network. 展开更多
关键词 波长分配 WDM光学网络 有限平行波长转换 FWM XGM 波混合 数字信号处理
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Design of Survivable Routing with and without Wavelength-continuity Constraints in WDM Networks
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作者 刘逢清 zeng +6 位作者 Qingji ZHU Xu YANG Xudong Xiao Shilin 《High Technology Letters》 EI CAS 2004年第4期1-5,共5页
The problem of routing logical links (lightpaths) on a physical topology of WDM networks in a way that the logical topology remains connected in the event of single physical link failure is called survivable routing. ... The problem of routing logical links (lightpaths) on a physical topology of WDM networks in a way that the logical topology remains connected in the event of single physical link failure is called survivable routing. This paper addresses the survivable routing problem with and without wavelength-continuity constraints by proposing a new Integer Linear Programming (ILP) algorithm, which is based on a simplified necessary and sufficient condition. Numerical results are given and discussed to show that survivable routing solutions of most logical topologies can be found by the algorithm of the authors. Furthermore, comparing with other similar methods, the above algorithm can find out a survivable solution in much shorter time, and it works especially well with sparse-connected logical topologies. The impact of wavelength-continuity constraints and the other factors that influence the probability to find out a survivable solution are also discussed in the paper. 展开更多
关键词 WDM网络 ILP算法 物理拓扑 逻辑拓扑 RWA通信 波分多路转换技术
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A Design and Implementation of Multicrypt Solution for DVB Receiver
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作者 陈君 Sun +4 位作者 Peng zeng Xuewen HOU Ziqiang 《High Technology Letters》 EI CAS 2004年第3期10-14,共5页
Conditional Access (CA) System is the essential basis of a Pay-TV System to charge the subscribers. This paper first introduces the standards and mechanisms for a Set-Top-Box(STB)to receive programs scrambled by d... Conditional Access (CA) System is the essential basis of a Pay-TV System to charge the subscribers. This paper first introduces the standards and mechanisms for a Set-Top-Box(STB)to receive programs scrambled by different CA systems. Then, according to DVB multicrypt solution, a design in detail for such a DVB receiver, I.e. STB is presented. Decoder manufacturers provide STBs with the standard DVB common interface and CA system providers provide detachable CA modules to plug into the STBs through Common Interface. This solution allows broadcasters and customers to change CA system without replacing the STB. Such a design has been implemented in a decoder based on LSI SC2000, and is proved to be an open and secure solution for conditional access. 展开更多
关键词 设计 DVB接收器 CA系统 电视系统
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Evaluation of the Importance of Web Pages
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作者 宋聚平 Wang +4 位作者 Yongcheng YIN Zhonghang zeng Yuming 《High Technology Letters》 EI CAS 2001年第4期23-26,共4页
Google’s algorithm on PageRank is analyzed in details. Some disadvantages of this algorithm is presented, for instance, preferring old pages, ignoring special sites and inaccurate judge of hyperlinks pointed out from... Google’s algorithm on PageRank is analyzed in details. Some disadvantages of this algorithm is presented, for instance, preferring old pages, ignoring special sites and inaccurate judge of hyperlinks pointed out from one page. Furthermore, author’s improved algorithm is described. Experiments show that the author’s consideration on evaluating the importance of pages can make an improvement over the original algorithm. Based on this improved algorithm a topic specific searching system have been developed. 展开更多
关键词 Search engine Authority of pages PAGERANK Hyperlink analysis
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The storage characters related to indica/japon ica differentiation of rice
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作者 zeng TENGSheng +1 位作者 KunihiroYasufumi QIANQian 《Chinese Rice Research Newsletter》 2000年第4期7-7,共1页
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水稻‘一目惚’抵御盐碱胁迫部分相关基因表达 被引量:1
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作者 吴楠 唐玙璠 +3 位作者 林宇杰 曾媛 马建 王宁宁 《分子植物育种》 CAS CSCD 北大核心 2019年第23期7634-7640,共7页
在本研究中,采用三种不同浓度(0.075 mol/L,0.05 mol/L,0.0375 mol/L)盐碱溶液胁迫水稻优良品种‘一目惚’,并通过表型观测及实时荧光定量PCR方法对植株进行验证分析。表型观测结果显示盐碱胁迫对于‘一目惚’的正常生长都有损伤,主要... 在本研究中,采用三种不同浓度(0.075 mol/L,0.05 mol/L,0.0375 mol/L)盐碱溶液胁迫水稻优良品种‘一目惚’,并通过表型观测及实时荧光定量PCR方法对植株进行验证分析。表型观测结果显示盐碱胁迫对于‘一目惚’的正常生长都有损伤,主要表现为叶片发黄及植株矮小,且相对来说碱胁迫损伤程度更大。但0.0375 mol/L浓度盐胁迫的植株在恢复生长7 d后生长态势与正常生长植株差异较小,推测该浓度处于‘一目惚’可应答胁迫范围内。在碱胁迫组中,植株的根部生长较为旺盛,且根长与胁迫浓度呈正相关。基因表达检测结果显示,基因OsAMT1;1和同家族基因OsAMT3;2在受胁迫植株中表达量增加,OSAMT基因家族与铵离子转运相关,表达上调表明氮代谢过程受到促进,植株以此抵御盐碱逆境;基因OsCBL4在受胁迫植株中表达下调,其作为Ca2+相关因子,在逆境来临时,形成盐碱耐受因子,以此减少盐碱逆境对植物代谢的伤害,具体分子机制还需要进一步研究。本研究创新性地采用优良耐盐碱品种‘一目惚’,进行验证性分析该品种的耐性研究,旨在提供一定的耐盐碱数据支持,为深入研究植物耐盐碱机制提供一定的实验帮助。 展开更多
关键词 ‘一目惚’(Hitomebore) 盐碱胁迫 基因表达
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