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1.
半乳甘露聚糖植物胶加工是我国70年代中期兴起的新兴产业。本文从我国植物资源发展的角度。重点论证了瓜尔豆(Cyanopsis tetragonoloba(L.)Taubert.)、田菁(Sesbania cannabina(Retz.)Pers.)、胡芦巴(Trigonella foenum-graecum L.)的生产情况,认为胡芦巴适应性强、产量高、易于机械化大面积种植与轮作,并具有改良土壤以及经济效益好等优势。因此,发展半乳甘露聚糖胶资源,大量种植胡芦巴是最好的选择。  相似文献   

2.
Chloroplast DNA from three barley cultivars and from one lettuce cultivar was prepared from chloroplasts isolated by Conventional differential centrifugation. Barley chloroplast DNA size was sensibly lower (130 kpb) than lettuce chloroplast DNA (150 kpb). Chloroplast DNAs from the three barley cultivars showed similar restriction fragment patterns after digestion with: BamHI, EcoRI or HindIII. The lettuce chloroplast DNA restriction pattern was very different from the barley chloroplast DNA restriction pattern.  相似文献   

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Swards of Dactylis glomerata cultivars (cvs) KM2 and Lutetia and of Lolium perenne cvs Aurora and Vigor were grown under full irrigation or prolonged summer drought (80 d) in a field experiment in the South of France.
After irrigation was withheld, leaf extension rates of all cvs fell by 90% within 9–12 d, and rapid scorching of laminae followed. Tiller mortality at the end of the drought was very different in the cocksfoot cvs (4% for KM2 and 76% for Lutetia) and intermediate (41%) for both ryegrass cvs. Following re-watering, rates of herbage regrowth were closely correlated with tiller survival. Measured minerals contributed c . 0·52 MPa to osmotic potential in all treatments, whereas water-soluble carbohydrates (WSC) contributed 0·25 MPa under irrigation and 0·46 MPa during drought.
There was no systematic difference between the two species for summer survival under severe drought, but large differences between the cocksfoot cvs. The traits most strongly associated with superior survival were: (a) a deep root system and greater water uptake at depth; (b) low water and osmotic potentials in surviving laminae, i.e. better tolerance to dehydration; (c) large pool-size of WSC reserves (fructans having degree of polymerization >4) in entire tiller bases (stubble); (d) low accumulation of proline in stubble; (e) rapid nitrogen uptake after rewatering.  相似文献   

5.
α and β chains of hemoglobin have been modified with cobalt(II) tetrasulfonated phthalocyanine in place of heme. They display properties very similar to those of iron(II) phthalocyanine modified α and β chains. Mixed together they form tetrameric cobalt(II) phthalocyanine hemoglobin.Incorporation of Co(II)L into α and β globins results in stabilization of the protein structure, which is shown by a marked increase in its helicity content. Cobalt phthalocyanine substituted α and β chains are able to combine reversibly with oxygen giving more stable oxygenated species than their native analogues. The rate of both processes is lower in the case of the modified α chain. Recombination of the phthalocyanine α and β chains with the alternate heme containing chains give tetrameric hybrid hemoglobins. These comprise two phthalocyanine modified subunits and two heme containing subunits. The helicity content of the tetrameric hybrid hemoglobin calculated for one subunit is lower that the arithmetic mean of helicities for its isolated subunits. This suggests a destabilizing chain-chain interaction within the tetramer. Unlike in the separated subunits, oxygen binding by hybrid hemoglobins is irreversible. Deoxygenation by argon bubbling leads to the formation of inactive species which in oxygen atmosphere undergo irreversible oxidation with destruction of the complex.  相似文献   

6.
青海赖草属一新种和一新变种   总被引:8,自引:1,他引:7  
1 青海赖草 新种 图1:1~9LeymusqinghaicusL.B.Cai,sp.nov.Fig.1:1~9HaecspeciesL.secalino(Georgi)Tzvel.proxima,aquodiffertspicisbrevibus,6~10cmlongis,brunneisvelbrunneolis,glumisangustelanceolatis,saepe1nervibus,inutroquelatereleviterasymmetricis,paleislemmatibusevidenterbrevi…  相似文献   

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红凤菜和白子菜总黄酮含量的动态变化   总被引:1,自引:0,他引:1  
红凤菜[Gynura bicolor (Willd. ) DC. ]和白子菜[G. divaricata (L. ) DC. ]均为菊三七属(Gynura Cass. )植物~([1]).红凤菜的嫩茎叶中含有丰富的营养成分,可作蔬菜食用~([2]);白子菜叶片在民间用于治疗糖尿病,动物实验证明其有显著的降血糖作用~([3]).  相似文献   

9.
中国芦荟染色体核型分析   总被引:8,自引:1,他引:7  
以中国芦荟为试验材料,按常规染色体压片法,观察中期分裂相并进行显微摄影。染色体类型按Levan方法分类,其核型为K(2n)=6st+8sm。  相似文献   

10.
粗山羊草(Aegilops tauschii(Coss.)Schmal.,DD,2n=14)是普通小麦(Triticumaestivum L.,AABBDD,2n=42)D染色体组的供体。粗山羊草中含有丰富的抗病,抗虫,抗逆,优质等优异基因,因此粗山羊草是改良普通小麦的宝贵遗传资源。但有关普通小麦与粗山羊草杂交的研究报道较少。本文试图通过对普通小麦与粗山羊草杂种后代的细胞遗传学和染色体分离规律的研究,探讨转移粗山羊草优异基因的方法和途径。  相似文献   

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百合科(Liliaceae)天门冬属(Asparagus (Tourn.)L.)植物具有悠久的药用历史,如天门冬(A.cochinchinesis (Lour) Merr.)早在汉代《神农本草经》中就被列为上品,具有滋阴、润燥、降火、止咳等功效。现代药理研究及临  相似文献   

13.
Zusammenfassung In Zisternen des granulären ER der Leydigschen Bindegewebszellen von Lymnea stagnalis L. finden sich Bündel relativ dickwandiger, drahtartig wirkender Mikrotubuli, deren Durchmesser 250 Å beträgt. Ihre Wand besteht aus 12 zirkulär angeordneten Untereinheiten, die in der Längsrichtung der Röhrchen als ca. 30 Å dicke, etwas unregelmäßig gestaltete Querbänder in Erscheinung treten. Es wird vermutet, daß die beschriebenen mikrotubulären Strukturen nur temporär ausgebildete Substrate geordneter Proteinkomplexe darstellen, die als Zwischenprodukte eines von den Leydigschen Zellen synthetisierten Materials aufzufassen sind.
Microtubular formations in cysterns of the endoplasmic reticulumElectronmicroscopical investigations of connective tissue cells in Lymnea stagnalis L. (Pulmonata)
Summary In the cisternae of granular endoplasmic reticulum of connective tissue cells of Lymnea stagnalis L. (so called Leydig cells) bundles of thread-like microtubules are present. One microtubule has a diameter of about 250 Å. The wall consists of 12 circular arranged subunits which, tangentially sectioned, are composed of close packed, diskshaped elements. It is assumed that the microtubules exhibit an intermediate stage of cellular synthesis, showing temporarily the pattern of a structural protein.
Herrn Prof. Dr. med. W. Bargmann zum 65. Geburtstag gewidmet.  相似文献   

14.
以大麦(HordeumVulgareL)叶片为实验材料,研究盐酸胍处理大麦类囊体膜对金属阳离子调节激发能分配的影响。结果表明:当未用盐酸胍处理时,Mg2+对类囊体膜的F686/F736比值有显著的刺激作用,而用不同浓度盐酸胍处理类囊体膜,则明显阻滞Mg2+调节激发能向PSII分配,表明盐酸胍处理可能损伤类囊膜上LHC—II与Mg2+调节作用有关的蛋白质,从而导致Mg2+调节效应降低.用SDS—PAGE方法研究盐酸胍处理后的类囊体膜色素蛋白复合物的组成变化,结果表明盐酸胍处理导致MIC—II中MICP1和LHCP2组分消失,这说明盐酸胍处理阻滞Mg2+调节效应可能与LJIC—II上的LHCP1,LHCP2受损有关。  相似文献   

15.
A new experimental system was developed for studying the hormonal mechanisms which control tracheid differentiation. In this system the tracheids redifferentiated from parenchyma cells in the hypocotyl of young Pinus pinea L. seedlings. The experimentally induced tracheids have unique shapes and patterns, and are therefore easily distinguished from the primary and secondary tracheids formed before the experiments. Auxin (0·1–1% NAA) alone sufficed to cause the redifferentiation of short tracheids, usually in discontinuous patterns across the hypocotyl. Gibberellin by itself did not induce redifferentiated tracheids. Combinations of auxin with gibberellin (0·1% NAA+0·1–1% GA3) promoted the differentiation of long tracheids (up to threefold greater than those induced by auxin) in continuous patterns along the stem axis. Gibberellin in the presence of auxin promoted tracheid elongation by stimulating intrusive growth of both the upper and lower ends of the differentiating tracheids. The role of auxin and gibberellin in controlling the evolution of tracheary elements, from tracheids to vessels and fibres, is discussed.  相似文献   

16.
紫苏腺毛的形态发生研究   总被引:4,自引:0,他引:4  
紫苏叶上有两种腺毛:质状腺毛和头状腺毛。两者都具1个基细胞、1个柄细胞和头部。前者的头部可由1、2、4或8个分泌细胞组成,扩展成质状;后者的头部由1、2或4个分泌细胞组成,聚成圆球状。两种腺毛的原始细胞都来源于原表皮细胞,经两次平周分裂产生基细胞、柄细胞和顶细胞。在腺毛后期的形态发生中,柄细胞的分化状态决定腺毛的类型。若柄细胞保持扁平关且处于分生状态时,其顶细胞将发育成质状腺毛的头部;若柄细胞纵向  相似文献   

17.
重组HIV-1壳体蛋白在转基因枸杞根系中的分泌表达   总被引:7,自引:1,他引:7  
P24壳体蛋白(capsid, CA)是HIV¬-1早期感染的一个重要标志.用含有植物表达载体pCAMBIA 1305.2- MA4-CA(包含GRP信号肽和MA4-CA融合基因)的农杆菌菌株侵染枸杞,将转有MA4-CA融合基因的转化株诱导生根,并进行毛状根的培养; western blot证实根系及培养液中的MA4-CA融合蛋白以二聚体的形式存在,分子量为50 kDa;免疫组织化学显示,CA定位在细胞浆、细胞壁和细胞间隙中,充分证实了利用GRP信号肽可以引导重组蛋白分泌表达。建立枸杞中HIV-1壳体蛋白的根分泌表达系统,为研究植物HIV-1 CA-病毒样颗粒(VLPs)疫苗奠定基础。  相似文献   

18.
紫苏叶上有两种腺毛:盾状腺毛和头状腺毛。两者都具1个基细胞、1个柄细胞和头部。前者的头部可由1、2、4或8个分泌细胞组成,扩展成盾状;后者的头部由1、2或4个分泌细胞组成,聚成圆球状。两种腺毛的原始细胞都来源于原表皮细胞,经两次平周分裂产生基细胞、柄细胞和顶细胞。在腺毛后期的形态发生中,柄细胞的分化状态决定腺毛的类型。若柄细胞保持扁平状且处于分生状态时,其顶细胞将发育成盾状腺毛的头部;若柄细胞纵向引长并迅速液泡化时,其顶细胞将发育成头状腺毛的头部。  相似文献   

19.
Artificial hemoglobins have been prepared with Mn(III) and Zn(II) tetrasulfonated phthalocyanines in place of heme. Their structure and properties have been investigated by difference spectroscopy, CD, epr, electrophoresis, and molecular weight estimation.Spectrophotometric titration data indicate the ratio of the reagents in this process to be 1:1. The visible absorption spectra show the main peak at 625 nm for the manganese compound and 681 nm for the zinc one. It is evident from CD experiments that incorporation of Mn(III)L into apohemoglobin increases helical content of the protein whereas that of Zn(II)L increases its unfolding due to the change of electronic configuration of Zn(II) ion on coordination with the protein.On the basis of spectroscopic and epr data, the formula of the manganese complex is suggested to be (O)Mn(IV)L-globin, whereas that of the zinc complex Zn(II)L-globin. Electrophoresis and molecular weight estimation indicate both complexes to be dimers.Manganese complex binds additional ligands as CN?, imidazole, CO, and NO. Spectroscopic and epr data indicate reduction of the manganese complex and formation of the NO adduct with probable formula (NO)+Mn(II)L-globin. Mechanism of this process is suggested.Both phthalocyanine globins are not able to combine reversibly with oxygen and cannot act as physiological oxygen carriers.  相似文献   

20.
根据对崖白菜的腊叶标本和武汉植物园栽培的崖白菜活体植物的研究,结合崖白菜的野外调查,认为全缘叶崖白菜应作为崖白菜的异名处理.  相似文献   

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