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多效唑调节制种花期的研究
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作者 余秋平 《杂交水稻》 CSCD 北大核心 1989年第S1期58-60,共3页
关键词 多效 九二○ 包颈 幼穗分化 调节制 父母本花期 杂交稻制种 黄泥田 深中耕 柱头外露率
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匈牙利工资调节制度的新变革
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作者 李峻 《世界经济文汇》 1985年第6期30-32,65,共4页
一从1979年起,匈牙利为了克服由于对外经济不平衡所造成的困难,采取了增加出口、减少进口、严格限制国内消费的方针。为此,对工资制度进行了一系列调整,实行了较为严格的措施,使职工名义工资不超过计划数字、实际收入持平或略有下降、... 一从1979年起,匈牙利为了克服由于对外经济不平衡所造成的困难,采取了增加出口、减少进口、严格限制国内消费的方针。为此,对工资制度进行了一系列调整,实行了较为严格的措施,使职工名义工资不超过计划数字、实际收入持平或略有下降、防止收入差距拉大等。近六年多来,匈工资调节几经变化,但总的路子是一致的,即:国家控制全国工资总额;工资增长和经济效益挂勾;不同企业规定不同的增长系数;超过一定增长幅度国家征收高额累进税。由于匈工资调节制度建立在缜密的预测和计算基础上,所以几年来,工资实际增长数与计划数字极为接近,基本上控制了消费基金的增长,对于恢复国民经济平衡起了积极的作用。但是,由于单纯强调工资的分配职能,忽视了它的刺激职能,也出现了一些弊病,不利于企业效率的提高,束缚了企业和职工的积极性和创造性,限制了市场机制的发挥。匈牙利早在八十年代初就明确指出。 展开更多
关键词 国民经济平衡 企业效率 增长数 调节制 企业规定 纳税能力 不平衡 企业收入 企业利润 八十年代
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多效唑调节制种花期要慎重
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作者 吕树保 陆福干 +1 位作者 罗炳福 戚长宽 《种子科技》 1990年第2期27-27,共1页
利用多效唑调节制种花期确是一种既经济省工又见效明显的好办法。但多效唑是一种高效植物生长延缓剂,能明显地使被处理植株矮化,节间缩短,叶片(鞘)增厚。使用不当或过量,不但不能起到调节花期的作用,反而会使被处理植株穗部畸形,颖壳变... 利用多效唑调节制种花期确是一种既经济省工又见效明显的好办法。但多效唑是一种高效植物生长延缓剂,能明显地使被处理植株矮化,节间缩短,叶片(鞘)增厚。使用不当或过量,不但不能起到调节花期的作用,反而会使被处理植株穗部畸形,颖壳变小和加重母本包茎程度。 展开更多
关键词 多效 植物生长延缓剂 调节制 颖壳 植株矮化 包茎 节间 花期相遇 喷施时间 穗分化
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植物生长调节剂“芸乐收”在冬小麦上的施用效果试验初报 被引量:3
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作者 胡铁军 张怀杰 +2 位作者 许熔熔 周飞 魏杰 《上海农业科技》 2020年第6期113-113,115,共2页
为探究植物生长调节剂"芸乐收"对小麦产量的影响和对小麦赤霉病的防治效果,特在小麦不同生长期施用该药剂进行了其田间施用效果试验。结果表明,施用"芸乐收"可促进小麦生长,从而提高小麦产量,且该药剂对赤霉病也有... 为探究植物生长调节剂"芸乐收"对小麦产量的影响和对小麦赤霉病的防治效果,特在小麦不同生长期施用该药剂进行了其田间施用效果试验。结果表明,施用"芸乐收"可促进小麦生长,从而提高小麦产量,且该药剂对赤霉病也有一定的防治效果。以在小麦返青期、孕穗期和灌浆期各喷施1次"芸乐收",对小麦的增产效果最好,可较常规处理增产9.32%。 展开更多
关键词 植物生长调节制 芸乐收 小麦 产量 赤霉病 防效
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发达国家与我国职业学校比较分析
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作者 蒋森华 《外国中小学教育》 北大核心 1990年第2期18-21,共4页
一、办学模式灵活性与正规化的差别发达国家职业学校的办学模式,相当灵活,授课形式有几个月的,也有1年——4年的;有全日制、半日制、日间部分时间调节制(一周一天至三天)、早班课、夜班课、函授等,为适应职前职后技术培训服务。联邦德... 一、办学模式灵活性与正规化的差别发达国家职业学校的办学模式,相当灵活,授课形式有几个月的,也有1年——4年的;有全日制、半日制、日间部分时间调节制(一周一天至三天)、早班课、夜班课、函授等,为适应职前职后技术培训服务。联邦德国每一类职业学校都不是一种学制,即同一专业, 展开更多
关键词 办学模式 专业设置 培训服务 教学计划 职业技术教育 调节制 授课形式 实践技能培养 职校毕业生 职业教育经费
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发达国家与我国职业学校比较分析
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作者 蒋淼华 《职业教育研究》 1989年第5期46-49,共4页
办学模式灵活性与正规化的差别发达国家职业学校的办学模式,相当灵活,授课形式有几个月的,也有1年——4年的;有全日制、半日制、日间部分时间调节制(一周一天至三天)、早班课、夜班课、函授等等,为职前职后技术培训服务。联邦德国每一... 办学模式灵活性与正规化的差别发达国家职业学校的办学模式,相当灵活,授课形式有几个月的,也有1年——4年的;有全日制、半日制、日间部分时间调节制(一周一天至三天)、早班课、夜班课、函授等等,为职前职后技术培训服务。联邦德国每一类职业学校都不是一种学制, 展开更多
关键词 办学模式 专业设置 培训服务 职业技术教育 教学计划 调节制 授课形式 职业技术学校 职业教育经费 农业学校
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DC LOOP-CURRENT DETECTING AND RESTRAINING METHODS FOR PARALLEL INVERTER SYSTEM
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作者 陈良亮 肖岚 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期1-6,共6页
DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the pa... DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance. 展开更多
关键词 DC loop-current DETECT digital adjustment parallel inverter
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风格派
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作者 一文 《青苹果》 2008年第Z1期121-121,共1页
最纯粹的抽象运动是荷兰的风格派,它在观念意识上最强调精神方面。1917年风格派创于阿姆斯特丹,它的核心人物是蒙德里安和凡·杜斯堡等人。
关键词 风格派 蒙德里安 立体主义 新造型主义 偶像崇拜 调节制 唯心主义哲学 理性传统 野兽主义 静态平衡
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The pH control optimization in the crop fertigation system using ANN 被引量:1
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作者 陈希 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期21-24,共4页
pH regulation is a complicated and comprehensive technique in the crop fertigation system. In this paper, a method is put forward to improve the quality of pH regulation, using artificial neural network to map a nonli... pH regulation is a complicated and comprehensive technique in the crop fertigation system. In this paper, a method is put forward to improve the quality of pH regulation, using artificial neural network to map a nonlinear relationship between pH interfering factor and the switching frequency of pH control valve, which achieves the dynamic feedforward compensation to the main control system. 展开更多
关键词 fertigation system pH regulation artificial neural network(ANN) BP algorithm
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Theoretical Study of Double Cost Function Linear Quadratic Regulator(LQR)
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作者 姜澜 王信义 永井正夫 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期80-86,共7页
Double cost function linear quadratic regulator (DLQR) is developed from LQR theory to solve an optimal control problem with a general nonlinear cost function. In addition to the traditional LQ cost function, anothe... Double cost function linear quadratic regulator (DLQR) is developed from LQR theory to solve an optimal control problem with a general nonlinear cost function. In addition to the traditional LQ cost function, another free form cost function was introduced to express the physical need plainly and optimize weights of LQ cost function using the search algorithms. As an instance, DLQR was applied in determining the control input in the front steering angle compensation control (FSAC) model for heavy duty vehicles. The brief simulations show that DLQR is powerful enough to specify the engineering requirements correctly and balance many factors effectively. The concept and applicable field of LQR are expanded by DLQR to optimize the system with a free form cost function. 展开更多
关键词 optimal control linear quadratic regulator (LQR) search algorithm front steering angle compensation control
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A New Tuning Method for Two-Degree-of-Freedom Internal Model Control under Parametric Uncertainty 被引量:10
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作者 Juwari Purwo sutikno Badhrulhisham Abdul aziz +1 位作者 Chin Sim yee Rosbi Mamat 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期1030-1037,共8页
Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcom... Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcome the weakness. However, the setting of parameter becomes a complicated matter if there is an uncertainty model. The present study proposes a new tuning method for the controller. The proposed tuning method consists of three steps. Firstly, the worst case of the model uncertainty is determined. Secondly, the parameter of set point con- troller using maximum peak (Mp) criteria is specified, and finally, the parameter of the disturbance rejection con- troller using gain margin (GM) criteria is obtained. The proposed method is denoted as Mp-GM tuning method. The effectiveness of Mp-GM tuning method has evaluated and compared with IMC-controller tuning program (IMCTUNE) as bench mark. The evaluation and comparison have been done through the simulation on a number of first order plus dead time (FOPDT) and higher order processes. The FOPDT process tested includes processes with controllability ratio in the range 0.7 to 2.5. The higher processes include second order with underdarnped and third order with nonminimum phase processes. Although the two of higher order processes are considered as difficult processes, the proposed Mp-GM tuning method are able to obtain the good controller parameter even under process uncertainties. 展开更多
关键词 tuning 2DOF-IMC model uncertainty dead time process Mp-GM tuning IMCTUNE
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Calculation method for trajectory following control for autonomous vehicles 被引量:2
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作者 Wu Jianwei Sun Beibei +1 位作者 Fu Qidi Liu Yanhao 《Journal of Southeast University(English Edition)》 EI CAS 2021年第4期356-364,共9页
The current literature lacks uniform calculation methods for following trajectory control for autonomous vehicles,including the calculation of errors,determination of tracking points,and design of feedforward controll... The current literature lacks uniform calculation methods for following trajectory control for autonomous vehicles,including the calculation of errors,determination of tracking points,and design of feedforward controllers.Hence,a complete calculation method is proposed to address this gap.First,a control equation in the form of an error is obtained according to the dynamic equation of the vehicle coordinate system and the trajectory following model.Secondly,the deviation of the vehicle state is obtained according to the current vehicle s state and the following control model.Finally,a linear quadratic regulator(LQR)controller with feedforward control is designed according to the characteristics of the dynamic equation.With the proposed LQR,the simulation of computational time,anti-interference,and reliability analysis of the trajectory following control is performed by programming using MATLAB.The simulation outcomes are then compared with the experimental results from the literature.The comparison indicates that the proposed complete calculation method is effective,reliable,and capable of achieving real-time and anti-interference following control performance.The simulation results with or without feedforward control show that the steady-state error is eliminated and that good control performance is obtained by introducing feedforward control. 展开更多
关键词 trajectory following autonomous vehicle feedforward control linear quadratic regulator(LQR)
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Adaptive Immune Evolutionary Algorithms Based on Immune Network Regulatory Mechanism 被引量:3
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作者 何宏 钱锋 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期141-145,共5页
Based on immune network regulatory mechanism, a new adaptive immune evolutionary algorithm (AIEA) is proposed to improve the performance of genetic algorithms (GA) in this paper. AIEA adopts novel selection operation ... Based on immune network regulatory mechanism, a new adaptive immune evolutionary algorithm (AIEA) is proposed to improve the performance of genetic algorithms (GA) in this paper. AIEA adopts novel selection operation according to the stimulation level of each antibody. A memory base for good antibodies is devised simultaneously to raise the convergent rapidity of the algorithm and adaptive adjusting strategy of antibody population is used for preventing the loss of the population adversity. The experiments show AIEA has better convergence performance than standard genetic algorithm and is capable of maintaining the adversity of the population and solving function optimization problems in an efficient and reliable way. 展开更多
关键词 evolutionary algorithm immune network ADAPTATION stimulation level.
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Evolution of plant microRNA gene families 被引量:14
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作者 Aili Li Long Mao 《Cell Research》 SCIE CAS CSCD 2007年第3期212-218,共7页
MicroRNAs (miRNAs) are important post-transcriptional regulators of their target genes in plants and animals, miRNAs are usually 20-24 nucleotides long. Despite their unusually small sizes, the evolutionary history ... MicroRNAs (miRNAs) are important post-transcriptional regulators of their target genes in plants and animals, miRNAs are usually 20-24 nucleotides long. Despite their unusually small sizes, the evolutionary history of miRNA gene families seems to be similar to their protein-codingcounterparts. In contrast to the small but abundant miRNA families in the animal genomes, plants have fewer but larger miRNA gene families. Members of plant miRNA gene families are often highly similar, suggesting recent expansion via tandem gene duplication and segmental duplication events. Although many miRNA genes are conserved across plant species, the same gene family varies significantly in size and genomic organization in different species, which may cause dosage effects and spatial and temporal differences in target gene regulations. In this review, we summarize the current progress in understanding the evolution of plant miRNA gene families. 展开更多
关键词 MICRORNAS post-transcriptional regulation tandem duplication segmental duplication
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Proline-rich tyrosine kinase 2 and its inhibitor PRNK 被引量:1
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作者 Hao Jia Guo Hong You Kai Xiao Yinbing 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第5期307-312,共6页
Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulat... Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK. 展开更多
关键词 Proline-rich tyrosine kinase 2 Pyk2 related non-kinase Dominant negative
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Iodothyronine deiodinase gene analysis of the Pacific oyster Crassostrea gigas reveals possible conservation of thyroid hormone feedback regulation mechanism in mollusks 被引量:1
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作者 黄雯 许飞 +3 位作者 曲涛 李莉 阙华勇 张国范 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期997-1006,共10页
Iodothyronine deiodinase catalyzes the initiation and termination of thyroid hormones(THs) effects, and plays a central role in the regulation of thyroid hormone level in vertebrates. In non-chordate invertebrates, on... Iodothyronine deiodinase catalyzes the initiation and termination of thyroid hormones(THs) effects, and plays a central role in the regulation of thyroid hormone level in vertebrates. In non-chordate invertebrates, only one deiodinase has been identified in the scallop C hlamys farreri. Here, two deiodinases were cloned in the Pacific oyster C rassostrea gigas( Cg Dx and C g Dy). The characteristic in-frame TGA codons and selenocysteine insertion sequence elements in the oyster deiodinase c DNAs supported the activity of them. Furthermore, seven orthologs of deiodinases were found by a tblastn search in the mollusk Lottia gigantea and the annelid C apitella teleta. A phylogenetic analysis revealed that the deiodinase gene originated from an common ancestor and a clade-specific gene duplication occurred independently during the differentiation of the mollusk, annelid, and vertebrate lineages. The distinct spatiotemporal expression patterns implied functional divergence of the two deiodinases. The expression of C g Dx and Cg Dy was influenced by L-thyroxine T4, and putative thyroid hormone responsive elements were found in their promoters, which suggested that the oyster deiodinases were feedback regulated by TH. Epinephrine stimulated the expression level of C g Dx and Cg Dy, suggesting an interaction effect between different hormones. This study provides the first evidence for the existence of a conserved TH feedback regulation mechanism in mollusks, providing insights into TH evolution. 展开更多
关键词 iodothyronine deiodinase Crassostrea gigas thyroid hormone (TH) CLONE expression analysis
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Evaluation of Antitumor,Immunomodulatory and Free Radical Scavenging Effects of A New Herbal Prescription Seaweed Complex Preparation 被引量:3
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作者 LIU Xin SHAO Changlun +2 位作者 KONG Wenwen FANG Yuchun WANG Changyun 《Journal of Ocean University of China》 SCIE CAS 2013年第3期515-520,共6页
Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and dige... Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and digestive cancer. However, little infor- mation is available about the pharmacodynamic basis. The antitumor, immunomodulatory and free radical scavenging effects of SCP were evaluated in this study. Transplanted tumor in vivo method was used to determine the antitumor effect. The effects on spleno- cyte proliferation and phagocytosis of macrophages in tumor-bearing mice were measured by the MTT method and the phagocytizing cock red blood cell (CRBC) method respectively. The scavenging activities of SCP on DPPH and hydroxyl radicals in vitro were investigated. It was found that the medium-dose and high-dose of SCP could significantly inhibit the growth of transplanted hepatic tumor of murine hepatocarcinoma cell line H22, and promote proliferation of splenocytes and phagocytosis of macrophages. SCP possessed noticeable scavenging activities on DPPH and hydroxyl radicals. The antiturnor effects of SCP might be achieved by im- proving immune system and scavenging free radicals, which is in accordance with the viewpoint of traditional Chinese medicine in promoting the body resistance and eliminating pathogenic factors for cancer treatment. 展开更多
关键词 traditional Chinese medicine preparation Seaweed complex preparation ANTITUMOR IMMUNOMODULATORY free radicalscavenging
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Mechanism of T cell regulation by microRNAs 被引量:7
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作者 Juan Liu Chang-Ping Wu +1 位作者 Bin-Feng Lu Jing-Ting Jiang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2013年第3期131-137,共7页
MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that can modulate target gene expression at post- transcriptional level and participate in cell proliferation, differentiation, and apoptosis. T cells ha... MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that can modulate target gene expression at post- transcriptional level and participate in cell proliferation, differentiation, and apoptosis. T cells have important functions in acquired immune response; miRNAs regulate this immune response by targeting the mRNAs of genes involved in T cell developmentp proliferationj differentiationp and function. For instancep miR-181 family members function in progression by targeting Bcl2 and CD69, among others. MiR-17 to miR-92 clusters function by binding to CREB 1, PTEN, and Bim. Considering that the suppression ofT cell-mediated immune responses against tumor cells is involved in cancer progression, we should investigate the mechanism by which miRNA regulates T cells to develop new approaches for cancer treatment. 展开更多
关键词 MICRORNA T cell gene expression
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DNA-dependent activator of interferon-regulatory factors inhibits hepatitis B virus replication 被引量:4
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作者 Qi-Ying Chen Ying-Hui Liu +3 位作者 Jian-Hua Li Ze-Kun Wang Jiang-Xia Liu Zheng-Hong Yuan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第22期2850-2858,共9页
AIM: To investigate whether DNA-dependent activator of interferon-regulatory factors (DAI) inhibits hepatitis B virus (HBV) replication and what the mechanism is. METHODS: After the human hepatoma cell line Huh7... AIM: To investigate whether DNA-dependent activator of interferon-regulatory factors (DAI) inhibits hepatitis B virus (HBV) replication and what the mechanism is. METHODS: After the human hepatoma cell line Huh7 was cotransfected with DAI and HBV expressing plas- mid, viral protein (HBV surface antigen and HBV e an- tigen) secretion was detected by enzyme-linked immu- nosorbent assay, and HBV RNA was analyzed by real- time polymerase chain reaction and Northern blotting, and viral DNA replicative intermediates were examined by Southern blotting. Interferon regulatory factor 3 (IRF3) phosphorylation and nuclear translocation were analyzed via Western blotting and immunofluorescence staining respectively. Nuclear factor-KB (NF-KB) activity induced by DAI was detected by immunofluorescence staining of P65 and dual luciferase reporter assay. Tran- swell co-culture experiment was performed in order to investigate whether the antiviral effects of DAI were dependent on the secreted cytokines. RESULTS: Viral protein secretion was significantly re- duced by 57% (P 〈 0.05), and the level of total HBV RNA was reduced by 67% (P 〈 0.05). The viral core particle-associated DNA was also dramatically down- regulated in DAI-expressing Huh7 cells. Analysis of involved signaling pathways revealed that activation of NF-KB signaling was essential for DAI to elicit antivi- ral response in Huh7 cells. When the NF-KB signaling pathway was blocked by a NF-KB signaling suppressor (I~:B^-SR), the anti-HBV activity of DAI was remarkably abrogated. The inhibitory effect of DAI was indepen- dent of IRF3 signaling and secreted cytokines. CONCLUSION: This study demonstrates that DAI can inhibit HBV replication and the inhibitory effect is asso- ciated with activation of NF-KB but independent of IRF3 and secreted cytokines. 展开更多
关键词 DNA-dependent activator of interferon regu-latory factor Antiviral activity Hepatitis B virus Nuclearfactor-~B Interferon regulatory factor-3
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Selection of Measured Signals in the Navigation Measuring Complex 被引量:1
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作者 柯芳 Andrey PROLETARSKY Konstantin NEUSIPIN 《Journal of Measurement Science and Instrumentation》 CAS 2011年第4期346-348,共3页
To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a select... To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased. 展开更多
关键词 selected navigation complex functional systems intellectual components observation level selforganiza tion
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