四体的

基本解释 (translations)

tetrasomic

与四体的相关的网络例句 [注：此内容来源于网络，仅供参考]

The presence of REE tetrad effects in apatites and whole rocks of S-type granites has been reported by Sha and Chappell (1999) and Zhao et al.(1999), respectively. The REE tetrad effect in minerals, such as apatite, spessartite, beryl, alkali feldspar and spodumene, from all zones of Altay No. 3 pegmatite has been found remarkable, and the fractionations among isovalent incompatible elements in these minerals are also significant. This paper puts forward that the REE tetrad effect is one of the basic features of peraluminous melts and the origin of REE tetrad effect might be probably related to some processes prior to the formation of pegmatite magma. The immiscibile liquid separation between silicate melt and hydrosaline melt may be responsible for it.

由于阿尔泰3号伟晶岩脉各带磷灰石以及与其共生的石榴石、绿柱石、碱性长石、锂辉石矿物均存在明显的稀土"四重效应"以及相同电价、相似离子半径的不相容元素间存在显著的分异，并结合最近赵振华等(1999)和Sha and Chappell(1999)报道S型花岗岩全岩和单矿物(磷灰石、独居石、长石、黄玉等)均存在稀土"四重效应"这一现象，本文研究提出，稀土"四重效应"是富挥发分过铝质岩浆体系的一个基本特征，其机制既不可能由含稀土的副矿物早期结晶引起残余熔体相中REE含量变化的结果，也不能定性地归因于流体相与熔体相相互作用过程中稀土元素在流体/熔体之间分异的结果，而很可能与伟晶岩岩浆形成之前某些过程密切相关，S型花岗岩岩浆在液相线以上存在硅酸盐熔体与高盐熔体的不混溶液相分离有可能是过铝质岩浆体系产生稀土"四重效应"的主要原因。

The specific activity of the dimer is twice that of the tetramer.

四体的比活是二体的一半。

It indicated that the yield of tetraploidy not more than 25% induced by inhibiting the first mitosis with CB, colchicine and 6-DMAP, respectively, while it can be induced with higher percentage by blocking PB1releasing with CB. The tetraploidy percentage of groups shock began at 15—22min after fertilization are higher than that shock began at 42min, and the yield of tetraploidy also increased with the CB density and time lasting.

结果表明，CB、6-DMAP和秋水仙素抑制扇贝第一次卵裂诱发四倍体的比例低于25%；采用CB抑制PB1可有效地诱导产生四倍体，从授精后42min提前到15—22min开始处理，抑制PB1的放出有助于提高四倍体的比例，在12℃，处理开始和终止时间分别在授精后20—22min和62—67min时(即PB2始出现时)，面盘幼虫四倍体率最高，为56.5%。

Specifically, itcontains 8 chapters.In chapter 1, the formation, structures, properties and the futureprospect of liposome were thoroughly reviewed;In chapter 2, the stibility and permeability of phopholipid -eleostericacid liposome were studied together with the effect of polymerizationof eleostearic acid. This membrane system was very sensitive to 〓,the effect of 〓 was clarified to increase the aggregation/fusion ofliposomes and made the permeability of mixed liposomes much higher;In chapter 3, two polymerizable conjugated diyne bolaamphiphiles were synthesized. They could form very stable mixed liposome, andthe diyne could be polymerized by UV light in bilayer liposomes, as aresult, the stability of mixed liposome against solvent or surfactantafter polymerization were enhanced. In chapter 4, two kinds of amphiphilic amino acids were synthesized andstable liposomes were formed therefrom After the condensationpolymerization of amino acid in bilayer liposomes, stable polypeptide liposomes were obtained, which had lower phase transition temperatureand higher permeability.In chapter 5, four kinds of glycolipids were synthesized and theiraggregation behavior in water was comparied. When incorporated intophospholipid bilayer membranes, they could increase the phase transitiontemperatures and inhibit the aggregation and fusion of mixedliposomesat lower temperature.In chapter 6 and 7, three kinds of steroidal bolaamphiphiles withdifferent chain lengths were synthesized. Incorporation of steroidalmoiety to the center of lipid bilayer membrane obviously increased themobility of lipid membrane and shifted Tc to lower temperature side incomparasion with cholesterol. The bolaamphiphile which was shorter thanthe hosted lipid bilayer membrane thickness influenced the lipid packingmore obviously.

全文共分8章：第一章对脂质体的形成、结构、性质及展望进行了较为详细的文献综述；第二章研究了磷脂-桐酸脂质体的稳定性，通透能力及桐酸的聚合对这些性质的影响；磷脂-桐酸混合脂质体为一类对〓灵敏的脂质体，〓的作用首先是使脂质体集聚然后使脂质体融合，并加速内包荧光物的释放；第三章通过合成两种可聚合共轭双炔双极性双亲分子DDCA，DDOL，研究了共双炔分子在双分子层脂质体膜上的聚合及对脂质体性质的影响，聚合可以提高脂质体相对于溶剂及表面活性剂的稳定性；第四章合成了两类氨基酸为极性基团的双亲分子，它们均可以在超声下形成稳定的脂质体结构；氨基酸基团可以在脂质体上进行缩聚反应，若聚合后脂质体表面仍有足够的亲水能力，则可得到稳定的多肽型脂质体；聚合后脂质体的相变温度降低，通透能力增加；第五章合成了四种亲水基团为单糖基的双亲分子GL-l，GL-2，GL-3， GL-4，研究了它们在水中的分散情况、集合体形态与分子结构的关系；在DMPC双分子层膜中加入糖脂分子可以使脂质体的相变温度提高，阻止脂质体在低温放置时的集聚与融合；第六章-第七章合成了三种不同碳链长度的双极性含胆甾环双亲分子 CL-1，CL-2，CL-3；它们可以象胆固醇一样与磷脂混合形成稳定脂质体，胆甾环基团位于脂质体双分子层膜的中间；与胆固醇的作用相反，它们可以增加磷脂双分子层膜的流动性，降低混合脂质体的相变温度；三种分子的作用与其碳链长度和磷脂双分子层膜的厚度有关，比膜厚度短的分子影响最大。

NodD binds to and bends target promoters through anchoring two tandem and individual specific DNA sites. NodD functions as a tetramer, which has a V-shaped main body. Tetrameric NodD is to change its own conformation rather than its oligomeric forms in response to small signal molecules. The specific interaction between each NodD DNA-binding domain and each specific DNA site does not alter itself in spite of naringenin induction, and the induced conformational change is transferred from protein to DNA. Only the DNA conformation incited by induced NodD is competent for RNA polymerase to form the transcriptional open complex. It cannot be excluded that NodD may have protein-to-protein contacts with RNA polymerase, and that the NodD conformational change may also directly contribute to the transcriptional open complex formation. However, the NodD conformational change itself cannot serve as the determinant of the transcriptional molecular switch.

通过研究，我们提出了初步的NodD操纵子激活模型：第一，四聚体是NodD蛋白的功能单位，它通过铆钉两个串联的相对独立的DNA靶位点结合被诱导的启动子；第二，小分子配基的结合是改变NodD四聚体的构象而不是引发不同形式的寡聚体，在我们的模型中，NodD四聚体缩小其V形主体的弯折角，进而缩短其DNA结合功能域的间距；第三，小分子信号的诱导并没有改变NodD的DNA结合域和其DNA靶位点的相互作用，NodD的构象改变由蛋白质经其双铆钉位点传递给DNA；第四，只有诱导状态的NodD激发的DNA构象才能有效地使RNA聚合酶形成转录开放复合物；第五，不排除NodD与RNA聚合酶可能有直接的相互接触位点，不排除NodD构象的改变可能直接有利于RNA聚合酶形成转录开放复合物，但是我们认为NodD构象改变本身不是充当转录激活开关的决定因素。

Lithologies are mostly sand and carbonate rocks, caps are mud rock, shale and magmatite. Entrap types are anticline, fault block rebuilt by breaking and the screened entrap diapered rock mass. The composition is CO_2, N_2, CH_4, C_2H_6 and He etc. It is magma air source body and its geologic fashions are intrusion and buried volcanic conduit. The relations between gas reservoirs and gas source bodies have three types: magma intrusion-breaking-communicated gas reservoir, magma intrusion-contacted CO_2 reservoir and buried volcanic conduit-contacted gas reservoir. The CO_2 migration in magma intrusion is consisted of fusing and crystallizing phases;it in volcanic conduit is consisted of near-surface effusion and crystallizing phases.The buoyancy of CO_2 in water far more than migration resistance in breaking or chink, CO_2 is easy float upward, the floating can results in differentiation of different density gases and concentration of sealed gas. The gas in sand reservoir firstly migrate into the higher porosity and coefficient of permeability sand, and along with the pressure going up it migrate into the lower. In magma intrusion-breaking-reservoir migration, CO_2 firstly migrate into watered breaking, began gravity differentiation and concentrate, the gas pressure time and again go up, CO_2 migrate into reservoir and concentrate under expansibility as the pressure reach upward a given extend. The CO_2 in reservoir experience four breaking modes: chemistry deposition, dissolution, diffusion and mechanic breaking, the pressure balance can be broken by faulting and the CO_2 will further migrate and form new reservoir.

济阳坳陷已发现的八里泊、阳25、平方王、平南、高青、花17 CO_2气藏主要储集层位有奥陶系、中生界、沙四段、沙三段、沙一段、馆陶组和明化镇组，储集层岩性以砂岩和碳酸盐岩为主，盖层以泥质岩、页岩和岩浆岩为主。；圈闭类型主要为受断裂改造的背斜、断块及刺穿岩体遮挡圈闭。；气体成分主要有CO_2、N_2、CH_4、C_2H_6、He等。；主要气源体为岩浆气源体，气源体的主要地质形式为侵入体和埋藏的火山通道。；气藏和气源体的空间关系有岩浆侵入体一断裂一气藏沟通型、岩浆侵入体-CO_2气储集层接触型和埋藏火山通道-气储集层接触型三种类型。；岩浆侵入体CO_2气运移分为熔融运移阶段和结晶运移阶段，火山通道中CO_2气运移分成近地表喷发阶段和结晶运移阶段。；断裂中，CO_2在水中的浮力远大于运移阻力，CO_2气容易上浮，CO_2在断裂中的易浮性导致不同密度气体的分异和走向上封闭的断裂气体相对富集。；气体在砂岩储集层运移聚集具有选择性，会优先进入孔隙度和渗透率较高的砂岩，随着压力增加，才会进入孔隙度和渗透率较低的砂岩；在岩浆气源体-断裂-储集层空间输导格架下，CO_2气在膨胀力的驱动下，首先进入含水的断裂并重力分异而聚集，气体压力会不断增高，当压力增至一定程度，CO_2气会向高孔隙度、渗透率的储集层运移并聚集。；在岩浆气源体-储集层接触空间输导格架下，CO_2气受膨胀力的驱动直接向储集层运移并聚集。；成藏的CO_2气会经历化学沉淀、溶解、扩散和机械破坏四种破坏方式，会受断裂切割而打破压力平衡，沿断裂进一步运移和聚集成藏。

The results showed that: at metaphase I, the homoeologous chromosome pairing among different F1 hybrids ranged from 2.0 to 11.4 bi-valents formed by homoeologous chromosomes per pollen mother cell, and very few multivalents, and even very few bivalents were formed by two chromosomes within one genome rather than homoeologous chromosomes in some PMCs; at anaphase I, all biva-lents were disjoined and most univalents were divided.

结果表明在中期I阶段，这些杂种一代的近缘染色体联会变化很大，每个花粉母细胞中二价体形成的数目从平均2个到11.4个不等，甚至在某些花粉母细胞中，还发现极少的多价体和非部分同源染色体所形成的单基因组内二价体；在后期I时，所有的二价体分离，同时多数单价体也分离，分离的二价体和分离的单价体都移向两极，从而形成两组染色体；因为这时完整花粉母细胞中分离的二价体在两组染色体中总是对应出现，从而根据半二价体上染色体重组的位置可以分析在二价体的四分体时期发生在非姊妹染色体之间的多种染色体交换类型，如单交换、三线双交换、四线双交换、四线三交换和四线多交换。

In order to explain clearly the variation status of embryo from tetrapoid Robinia pseudoacacia and fully use the variation resource initiated in the sexual reproduction of TRP in the further improvement of TRP, the classification and vitalities of seed embryos from tetraploid Robinia pseudoacacia were studied. The main results are as follow. According to the cotyledon number, color and plumpness, the seed embryos of TRP could be divided into 5 types: YVT (yellow, very replete,2 cotyledons), YMT( yellow, more replete,3 cotyledons ), YRF ( yellow, replete,4 cotyledons ), GNT ( green, no-replete, 2 cotyledons ) and WNT ( white, no-replete, 2 cotyledons ).

为了阐明刺槐同源四倍体种子胚变异状况及充分利用刺槐同源四倍体有性过程创造的变异资源对四倍体刺槐进行遗传改良，研究了刺槐同源四倍体种子胚类型及其生活力特征，主要结论如下：刺槐同源四倍体种子胚按照子叶数量、颜色及饱满程度，可以划分出5个类型：黄二、黄三、黄四、绿二及白二，所有类型种子胚混合平均单胚重量接近二倍体的1/2。

Thus, the meiotic chromosome cofigurations showed that the tetraploids and hexaploids in C.reticulata allopolyploids, and the appearance of a few tetravalents in some populations might indicatehomology of chromosomes in different genomes to some extent.

根据减数分裂的构型，我们认为，四倍体和六倍体分别为异源四倍体和异源六倍体，少数四价体的存在表明染色体有部分同源性。

In meiosis of pollen mother cells of the tetraploids and the hexaploids, only bivalents were observed in most of the populations, although in several populations or individuals a few univalents or tetravalents appeared. In the hexaploids, hexavalents were not observed.

四倍体和六倍体的花粉母细胞减数分裂染色体构型在大多数居群都为二价体(四倍体中30个二价体，六倍体中45个二价体)，少数居群或是个体除二价体为主外还出现单价体和四价体，六倍体类型没有出现六价体构型。

与四体的相关的网络解释 [注：此内容来源于网络，仅供参考]

quadrivalent：四价的;四价体

quadriplex 四显性组合 | quadrivalent 四价的;四价体 | quadruplex 四显性组合

quadrivalent：四价的 四价染色体

四迭体 quadrigeminal bodies; corpora quadrigemina; quadrigeminum | 四价的;四价染色体 quadrivalent | 康布兰德猴面珍珠贝 Quadrula intermedia

tetrabranchiate：四鳃的

tetrabranch 四鳃软体类 | tetrabranchiate 四鳃的 | tetrabromated 四溴化的

tetraploid：四倍的 四倍体小麦

tetraplegia 四肢麻痹 | tetraploid 四倍的 四倍体小麦 | tetraploidplant 四倍体植物

tetartohedral：四半面体的

陆龟 Testudo | 四半面体的 tetartohedral | 四分半面形 tetartohedral form

tetragynous：四子房的;四花柱的

四雌蕊花 tetragynia | 四子房的;四花柱的 tetragynous | 四染色体单位体 tetrahaploid

tetrahydric：四氢的

tetrahexahedron 四六面体 | tetrahydric 四氢的 | tetrahydro 四氢化

tetrameric：四聚体的

tetramer 四聚体 | tetrameric 四聚体的 | precursor 前体

tetrasomic：四体

称为双单体;如双体中多暸一条染色体,使某一对同源染色体变成叁条,就称叁体(trisomic),即2n 1;双体中某一对同源染色体变成四条同源染色体,称为四体(tetrasomic)即2n 2;双体中增加暸二条非同源染色体的称为双叁体(ditrisomic),

thalloid：似叶状体的 , 似菌体的

四足动物 tetrapod | 似叶状体的 , 似菌体的 thalloid | 饲虫箱 wormery