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系统功能语法中的“基调”与“情态”的关系研究 被引量:1
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作者 唐建福 《宜宾学院学报》 2008年第3期105-107,共3页
"情态"是一个经久不衰的研究主题,长期以来就是许多哲学家、逻辑学家和语言学家研究的对象之一。由于语言是一个动态的系统,语言的某一个子系统与其他系统必然存在着联系。文章在涉及情态系统与基调系统的关系时,主要讨论了... "情态"是一个经久不衰的研究主题,长期以来就是许多哲学家、逻辑学家和语言学家研究的对象之一。由于语言是一个动态的系统,语言的某一个子系统与其他系统必然存在着联系。文章在涉及情态系统与基调系统的关系时,主要讨论了五大基调在陈述句、特殊疑问句、一般疑问句和命令句中表达情态的意义,指出了基调是情态的语法实现方式。 展开更多
关键词 系统功能语法 “基调” “情态” 关系
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《再别康桥》是一种“基调”吗?
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作者 李坚 《中学语文教学》 北大核心 2001年第8期28-28,共1页
关键词 《再别康桥》 徐志摩 抒情诗 高中 语文 “基调”
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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话剧舞台语言中“调”的音乐性研究
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作者 黄韵茜 《戏剧之家》 2023年第28期3-5,共3页
话剧舞台语言的音乐特性是在解释并发展情节的基础上对“调”的探索,本文拟以斯坦尼斯塔夫斯基表演理论为理解舞台语言“音乐性”的基础,从舞台语言的“基调”及“语调”两个维度重释“音乐性”的具体含义。在其中融入基础乐理作为分析... 话剧舞台语言的音乐特性是在解释并发展情节的基础上对“调”的探索,本文拟以斯坦尼斯塔夫斯基表演理论为理解舞台语言“音乐性”的基础,从舞台语言的“基调”及“语调”两个维度重释“音乐性”的具体含义。在其中融入基础乐理作为分析工具,在对语调的音乐性分析中尝试构想舞台语言的“总乐谱”,在宏观与微观层面捕捉舞台语言的音乐性能。 展开更多
关键词 斯坦尼斯拉夫斯基舞台语言 “音乐性” “远景” “基调” “语调”
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Camptothecin and 10-Hydroxycamptothecin Accumulate Differentially Under Specific Developmental Control in Camptotheca acuminata 被引量:11
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作者 祖元刚 唐中华 +1 位作者 于景华 赵春建 《Acta Botanica Sinica》 CSCD 2003年第4期494-499,共6页
Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics ... Camptotheca acuminata Decaisne is a tree unique to China, producing terpenoid indole alkaloid (TIA), camptothecin (CPT), and 10-hydroxycamptothecin (HCPT), which possesses strong anti-cancer bioactivity. The dynamics of HCPT and CPT during seed maturation, seed germination, postgerminative development and daily growth were measured by High Performance Liquid Chromatography (HPLC). This article provides some evidence for presenting the theory that each characteristic of HCPT and CPT accumulation is under developmental regulation and then attempt to elucidate the metabolic relationships between them. HCPT accumulates particularly in young tissues and organs and is relatively unstable, while the distribution of CPT is more ubiquitous and stable. Their different distribution properties suggest that HCPT and CPT are differentially regulated and play distinct roles:during development. 展开更多
关键词 Camptotheca acuminata CAMPTOTHECIN 10-HYDROXYCAMPTOTHECIN CONTROL DEVELOPMENT
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Plant Anthocyanin Synthesis and Gene Regulation 被引量:6
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作者 马廷蕊 张金文 +1 位作者 梁慧光 柳永强 《Agricultural Science & Technology》 CAS 2012年第3期507-511,540,共6页
This paper aims to explain the biochemistry of anthocyanin synthesis based on an overview of plant anthocyanin synthesis genes and environmental factors in the regulation of anthocyanin metabolism. The results show t... This paper aims to explain the biochemistry of anthocyanin synthesis based on an overview of plant anthocyanin synthesis genes and environmental factors in the regulation of anthocyanin metabolism. The results show that: ① The metabolism of anthocyanins in plants is affected by the temperature, light, ultraviolet, fertilization status, hormone levels and other factors, which affect the military anthocyanin biosynthetic genes, and then induce or inhibit the synthesis of anthocyanins. ② In the regulation of genes, some of the structural genes of anthocyanin synthesis showed promoting effect, while others showed inhibitory effect. At different environ- mental conditions, the regulation of gene activation and inhibition of the amount of different regulatory genes that anthocyanin accumulation is different, and cause different colors of plant-organs production. ③ In different environmental factors or hor-mones induced to produce the same or different regulation of gene expression changes in regulatory genes, resulting in several different anthocyanins or anthocyanin ratio changes, so that the color of plant organs in different colors. 展开更多
关键词 ANTHOCYANIN Structural protein Regulatory genes regulation factors
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Extracellular Calmodulin Induces rbcS-3A Gene Expression in Suspension Culture of Tomato Cells 被引量:2
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作者 张素巧 马力耕 孙大业 《Acta Botanica Sinica》 CSCD 2000年第6期653-655,共3页
利用番茄 (LycopersicumesculentumMill.)悬浮培养细胞为材料 ,以3 2 P标记的寡核苷酸 (40bp)为探针检测了细胞外钙调素对番茄细胞rbcS_3A及rbcS_3C基因表达的影响。当向暗中培养的番茄悬浮细胞 (第 7天 )中加入外源纯化钙调素 (10 -7mo... 利用番茄 (LycopersicumesculentumMill.)悬浮培养细胞为材料 ,以3 2 P标记的寡核苷酸 (40bp)为探针检测了细胞外钙调素对番茄细胞rbcS_3A及rbcS_3C基因表达的影响。当向暗中培养的番茄悬浮细胞 (第 7天 )中加入外源纯化钙调素 (10 -7mol/L)并处理 2 4h后 ,rbcS_3A基因的表达明显增加 ,而相同浓度的S_10 0蛋白和BSA则没有作用。加入外源钙调素 (10 -7mol/L)对rbcS_3C基因的表达没有影响。上述结果表明细胞外钙调素对暗中培养的番茄rbcS基因的表达有调控作用 ,并且这种调控作用具有亚型特异性 ,即对番茄rbcS_3A基因的表达有诱导作用 ,而对番茄rbcS_3C基因的表达没有作用。 展开更多
关键词 extracellular CaM rbcS_3A gene TOMATO
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Advances in the Regulation of RpoS Protein Expression and Its Function in Bacteria 被引量:2
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作者 王淑娴 李天保 +4 位作者 叶海斌 魏鉴腾 王勇强 刁菁 杨秀生 《Agricultural Science & Technology》 CAS 2012年第6期1215-1221,1225,共8页
RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulat... RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulated at three levels: transcription level, translation level and post-translational level. Environmental stress enters bacterial cells through signal transduction and leads to a series of variations in microenvironment, thereby causing changes of regulator and controlling its levels based on the direct and indirect interaction between regulator and RpoS protein. In addition, RpoS protein has played special roles in bacteria, therefore the changes of RpoS protein levels will lead to variations in expression levels of a large number of genes, thereby causing variations of bacterial response to different environmental stress and changes of certain characteristics of bacteria, which provides a new strategy for the control of bacterial diseases in the future. This paper reviewed the recent progress on the regulation of RpoS protein expression and its function in several common bacteria. Due to the functional complexity of RpoS protein, there are still a lot of unknown functions to be further identified. 展开更多
关键词 RpoS or σ S rpoS gene Expression regulation Environmental stress RpoS function
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Isolation and Characterization of a Mitochondrial atp6 Gene from Soybean (Glycine max) 被引量:1
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作者 贺超英 吴晓雷 +2 位作者 张劲松 盖钧镒 陈受宜 《Acta Botanica Sinica》 CSCD 2001年第1期51-58,共8页
Mitochondrial ATPase (mtATPase) complex plays vital roles in higher plants. It consists of a few subunits. In the present study, a new copy of the mtATPase subunit 6 (EC 3.6.1.34) gene (atp6) was cloned and characteri... Mitochondrial ATPase (mtATPase) complex plays vital roles in higher plants. It consists of a few subunits. In the present study, a new copy of the mtATPase subunit 6 (EC 3.6.1.34) gene (atp6) was cloned and characterized from Glycine max (L.) Merr., which has the shortest opening reading frame of 223 amino acids in all organisms examined and designated as the atp6 copy3 (atp6_3). PCR amplifications of the atp6_3 from 9 soybean cultivars combined with sequencing analysis suggested its wide occurrence in G. max . RFLP analysis of a RILs population implied that paternal inheritance of the atp6_3 might occur in G. max at undetermined frequency. Under salicylic acid (SA)_treated condition, the expression of the atp6 gene was significantly inhibited. The possible role of this inhibition was discussed. 展开更多
关键词 Glycine max mitochondrial atp6 down_regulation salicylic acid
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Cloning of cDNA Encoding CCoAOMT from Populus tomentosa and Down-regulation of Lignin Content in Transgenic Plant Expressing Antisense Gene 被引量:22
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作者 魏建华 赵华燕 +2 位作者 张景昱 刘惠荣 宋艳茹 《Acta Botanica Sinica》 CSCD 2001年第11期1179-1183,共5页
cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically... cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically in the developing secondary xylem and its expression was coincident with lignification. The antisense CCoAOMT cDNA was transformed into P. tremula x P. alba mediated by Agrobacterium tumefaciens ( Smith et Townsend) Conn. Transgenic plants were identified with PCR, PCR-Southern and Southern analysis. Lignin content in 5- to 6-month-old transgenic plants was measured. One of the transgenic lines had significant reduction of 17.9% in Klason lignin content as compared with that of untransformed poplar. The results demonstrate that antisense repression of CCoAOMT is an efficient way to reduce lignin content for improving pulping property in engineered trees. 展开更多
关键词 RT-PCR Populus tomentosa CCOAOMT antisense RNA LIGNIN
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Transcriptional Regulation of 10 Mitochondrial Genes in Different Tissues of NCa CMS System in Brassica napus L. and Their Relationship with Sterility 被引量:3
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作者 危文亮 王汉中 刘贵华 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期72-80,共9页
Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revea... Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed. 展开更多
关键词 Brassica napus L. cytoplasmic male sterility (CMS) mitochondrial gene expression restorer gene transcriptional regulation
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Regulatory genes controlling neural stem cells differentiation into neurons
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作者 张丽 顾振伦 秦正红 《Neuroscience Bulletin》 SCIE CAS CSCD 2006年第5期294-300,共7页
The recent progress in neural stem cells (NSCs) research has shed lights on possibility of repair and restoration of neuronal function in neurodegenerative diseases using stem cells. Induction of stem cells differen... The recent progress in neural stem cells (NSCs) research has shed lights on possibility of repair and restoration of neuronal function in neurodegenerative diseases using stem cells. Induction of stem cells differentiate into mature neurons is critical to achieve the clinical applications of NSCs. At present, molecular mechanisms modulating NSC differentiation are not fully understood. Differentiation of stem cells into neuronal and glial cells involves an array of changes in expression of transcription factors. Transcription factors then trigger the expression of a variety of central nervous system (CNS) genes that lead NSCs to differentiate towards different cell types. In this paper, we summarized the recent findings on the gene regulation of NSCs differentiation into neuronal cells. 展开更多
关键词 neural stem cells DIFFERENTIATION gene regulation
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Gene Expression and Regulation of Blastocyst Formation 被引量:1
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作者 陈瑛 张玉兰 张秋野 《Developmental and Reproductive Biology》 2002年第1期75-81,共7页
Blastocyst formation is a crucial stage of early embryo development.Cell junction proteins and cell adhesion associated proteins are involved in the establishment of cell junction,and subsequently induce cell compacti... Blastocyst formation is a crucial stage of early embryo development.Cell junction proteins and cell adhesion associated proteins are involved in the establishment of cell junction,and subsequently induce cell compaction,blastocyst formation,differentiation of trophectoderm and maintenance of blastocyst expansion.Genes regulating development and differentiation participate in embryo development and differentiation of inner cell mass and trophectoderm,which controls the transition from the undifferentiation to differentiation state.Furthermore,cytokine and growth factor have influence on the proliferation of cells of inner cell mass.In a word,many proteins and factors are involved in the gene expression and regulation of blastocyst formation. 展开更多
关键词 BLASTOCYST gene expression gene regulation
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Cloning of Brassica napus EIN3 Gene and Its Expression Induced by Sclerotinia sclerotiorum 被引量:4
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作者 许李明 黄军艳 +2 位作者 刘学群 覃瑞 刘胜毅 《Agricultural Science & Technology》 CAS 2009年第2期33-36,共4页
[Objective] The study was to investigate roles of Brassica napus EINB in ( BnEIN3 ) resistance to Sclerotinia sclerotiorum. [ Methods] Genomic PCR and RT-PCR were carded out to isolate genomic DNA and cDNA sequences... [Objective] The study was to investigate roles of Brassica napus EINB in ( BnEIN3 ) resistance to Sclerotinia sclerotiorum. [ Methods] Genomic PCR and RT-PCR were carded out to isolate genomic DNA and cDNA sequences of BnEIN3 from oilseed rape, based on the highly conserved region of EIN3 gene from Arabidopsis thaliana and the homologous sequences of oilseed rape ESTs. Expression levels of BnEIN3 were detected in three varieties of oilseed rape inoculated with S. sclerotiorum by real-time quantitative PCR.[Results] A 1 947 bp DNA fragment was obtained from oilseed rape. The fragment shared 82% identity to A. thaliana EIIV3, encoded 614 amino acids containing an EIN3 domain, and was named as BnEIN3. Real-time PCR results showed that expression patterns of BnEIN3 were drastically different in different varieties. In highly resistant oilseed rape variety D083, BnEIN3 expression level was significantly increased 72 h after S. sclerotiorum inoculation whereas in middle resistant and susceptible varieties Zhongshuang 9 and 84039, BnEIN3 expression was suppressed. [ Conclusion ] BnEIIV3 may play an important role in oilseed rape resistance to S. sclerotiorum. 展开更多
关键词 Brassica napus L. EINB RESISTANCE Sclerotinia sclerotiorum Real time PCR
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Effects of Selenium Dioxide on Apoptosis, Bcl-2 and P53 Expression, Intracellular Reactive Oxygen Species and Calcium Level in Three Human Lung Cancer Cell Lines 被引量:5
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作者 魏亚明 于海建 +1 位作者 赵熙妍 白海 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第3期141-146,193,共7页
Objective: To evaluate the anti-tumor effects of SeO2 and its mechanisms on three human lung cancer cell lines. Methods: Three lung cancer cells A549, GLC-82 and PG were treated with 3-30 μmol/L SeO2. Flow cytometry ... Objective: To evaluate the anti-tumor effects of SeO2 and its mechanisms on three human lung cancer cell lines. Methods: Three lung cancer cells A549, GLC-82 and PG were treated with 3-30 μmol/L SeO2. Flow cytometry was used to detect apoptosis, and analyze the changes of expression of p53 and Bcl-2, as well as ROS and Ca2+ level within cells. Results:SeO2 markedly inhibited cell proliferation and viability, and prompted apoptosis after 48 h treatment. SeO2 at 10 μmol/L induced 47.8% apoptosis in A549 cells, 40.8% in GLC-82 cells, 18.2% in PG cells. SeO2 at 30 μmol/L induced 37.8% apoposis in PG cells,but did not increase apoptotic raes in other two cells. SeO2 could down-regulate the mean fluorescent intensity of Bcl-2 from 65.8 to 9.6 in A549, but not in GLC-82 and in PG cells, up-regulate wild type p53 level in all three cells. SeO2 decreased the ROS and Ca2+ level markedly within three tested cells. Conclusion: SeO2 showed anti-tumor effect via apoptosis pathway in three lung cancer cell lines. The decrease of ROS and Ca2+ level within cells as well as regulation of Bcl-2 and p53 expression may play important roles in above apoptotic procedure. 展开更多
关键词 selenium dioxide APOPTOSIS BCL-2 P53 reactive oxygen species (ROS) CALCIUM lung cancer
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Design of a CMOS Current-Adjustable Charge-Pump Circuit Insensitive to Power Supply and Temperature
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作者 赵晖 徐栋麟 +3 位作者 潘莎 杨柯 任俊彦 章倩苓 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第3期260-265,共6页
A CMOS charge-pump circuit with adjustable current is presented.A bandgap voltage reference,a low drop-out regulator,and a capacitive DC-DC voltage-booster are used to generate supply voltage for the current reference... A CMOS charge-pump circuit with adjustable current is presented.A bandgap voltage reference,a low drop-out regulator,and a capacitive DC-DC voltage-booster are used to generate supply voltage for the current reference.This generated voltage is insensitive to the changes of external power supply voltage and temperature,while the current reference itself is insensitive to temperature.The circuit is designed in 0.18μm 1.8V standard digital CMOS process.The simulated results show that the performance of the circuit is satisfied. 展开更多
关键词 current-adjustable charge-pump bandgap low drop-out regulator DC-DC voltage-booster
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Fluctuation Resonance of Feed Forward Loops in Gene Regulatory Networks 被引量:1
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作者 董翊 侯中怀 辛厚文 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期359-365,447,共8页
The feed forward loop (FFL), wherein a gene X can regulate target gene Z alone or cooperatively with gene Y, is one of the most important motifs in gene regulatory networks. Gene expression often involves a small nu... The feed forward loop (FFL), wherein a gene X can regulate target gene Z alone or cooperatively with gene Y, is one of the most important motifs in gene regulatory networks. Gene expression often involves a small number of reactant molecules and thus internal molecular fluctuation is considerable. Here we studied how an FFL responds to small external signal inputs at gene X, with particular attention paid to the fluctuation resonance (FR) phenomenon of gene Z. We found that for all coherent FFLs, where the sign of the direct regulation path from X to Z is the same as the overall sign of the indirect path via Y, the FR shows a regular single peak, while for incoherent FFLs, the FR exhibits distinct bimodal shapes. The results indicate that one could use small external signals to help identify the regulatory structure of an unknown FFL in complex gene networks. 展开更多
关键词 Gene regulatory network Fluctuation resonance Feed-forward-loop
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Design of a Bandgap Reference with a Wide Supply Voltage Range 被引量:4
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作者 孙越明 赵梦恋 吴晓波 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1529-1534,共6页
An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management (PM) controller chips applied to telecommunication, automotive, lighting equipment, ... An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management (PM) controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio (PSRR) and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD (Bipolar-CMOS-DMOS) technology. The experimental results show that all main expectations are achieved. 展开更多
关键词 wide supply voltage range bandgap reference line regulation sleep mode micro power
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Advances in Melatonin and Its Functions in Plants
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作者 张娜 张海军 +2 位作者 杨荣超 黄韫宇 郭仰东 《Agricultural Science & Technology》 CAS 2012年第9期1833-1837,共5页
Abstract Melatonin (N-acetyi-5-methoxytryptamine) is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has ... Abstract Melatonin (N-acetyi-5-methoxytryptamine) is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out. 展开更多
关键词 MELATONIN Plant ANTIOXIDANT Qrowth regulator PHOTOPERIOD
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The Progress on Abnormal Development Mechanism
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作者 张天宝 《Developmental and Reproductive Biology》 1996年第2期69-76,共8页
What summarized in this paper is the progress in recent years' in the causdive mechanism on study of developmental toxicants as chemical teratogenesis in three aspects.(1) It is about the phenomena and the possibl... What summarized in this paper is the progress in recent years' in the causdive mechanism on study of developmental toxicants as chemical teratogenesis in three aspects.(1) It is about the phenomena and the possible reason of chemical teratogenesis in the preimplantation period. These research results are contrary to the past traditional concepts. (2) Due to using much more molecular biology methods, it can be observed more dead foetus phenomena before birth, which cannot be done previously and are of great value for reference. (3) When analyzing the genetic reason of chemical abnormal, a new research idea may be showed, i.e. the developmental abnormal due to chemical teratogenesis is induced with association of more relative genes and their expression abnormal. 13 references are involved in. 展开更多
关键词 Abnormal development Chemically induced defect Toxicology
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