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101.
氧化棉子糖分子内交联猪血红蛋白对其结构功能的影响 总被引:6,自引:3,他引:3
用高碘酸盐氧化法制得氧化开环棉子糖,并用它分别修饰处在氧合及脱氧构象的猪血红蛋白得到两种不同的修饰衍生物。与天然蛋白质相比,两种修饰后的猪血红蛋白衍生物均具有明显的抗α2β2四聚体解聚的特性。经SDS-PAGE和反相HPLC分析发现这两种修饰衍生物均为分子内交联产物,而且交联都发生于2个β亚基之间,两种交联产物的紫外-可见光谱没有明显差别,但在相同浓度下,脱氧构象下被修饰蛋白质的荧光发射光强度明显 相似文献
102.
The taxonomical history of the woody group(peonies) in the genus Paeonia is reviewed in the present paper. The group is endemic to China, but Paeonia suffruticosa is
commonly cultivated throughout the north temperate region and has long been known as “the
King of Flowers” in China. However, the taxonomy of the group had been neglected before
the 1990' s. Since 1990, a number of new species and subspecies have been published. With
the support from the National Geographic Society, the senior author of the present paper and
his coworkers have made expeditions to all parts of the distribution area of the group, visited
all the type localities and sampled a total of 64 populations. Based on the character analysis
and examination of the type specimens or photos, each taxon is reviewed with its name
checked nomenclaturally, and finally the taxonomy of the whole group is revised. As a result, eight species, three of which each contains two subspecies, are recognized. They are
Paeonia suffruticosa Andrews subsp. suffruticosa and subsp. yinpingmudan D. Y.
Hong, K. Y. Pan et Z. W. Xie, P. jishanensis T. Hong et W. Z. Zhao, P. qiui Y. L.
Pei et D. Y. Hong, P. ostii T. Hong et J. X. Zhang, P. rockii (S. G. Haw et L. A.
Lauener )T. Hong et J. J. Li subsp. rockii and subsp. taibaishanica D. Y. Hong, P. decomposita Hand.-Mazz. Subsp. decomposita and subsp. rotundiloba D. Y. Hong, P.
delavayi Franeh. and P. ludlowii (Stern et Taylor)D. Y. Hong. P. baokangensis Z. L.
Dai et T. Hong and P. yananensis T. Hong et M. R. Li are considered as hybrids between
P. rockii and P. qiui and between P. rockii and P. jishanensis respectively. In addition, the reduction of a number of names recently published to synonyms is explained. 相似文献
103.
104.
105.
Fifteen natural populations representing all the taxa in Adenophora potaninii
complex were investigated using vertical slab polyacrylamide gel electrophoresis. Allozyme
data for ten loci of seven enzymes demonstrate high levels of genetic variation within populations, with the values of P=0.40~0.70, A=1.5~2.5 and He=O.102~0.291. At specific level, there existed the highest variation in A. wawreana (A= 2.10, P=0.63, He
=0.237), followed by those of A. lobophylla (A=1.85, P=0.60, He=0.204) and A.
potaninii (A=1.83, P=0.60, He =O.188). Based on Wright's F-statistics, the outcrossing rates( t ) were 0.86 ( A.wawreana ), O.74 ( A.potaninii ) and 0.63 ( A.lobophylla). The analysis on population genetic structure indicates that most variation resided
within populations, which is consistent with the high rate of outcrossing rates in the complex. On the basis of genetic identity(I), cluster analysis shows that there was high genetic divergence between A. lobophylla populations and A. wawreana-A, potaninii clade,
while no clear genetic difference was found between A. wawreana populations and A.
potaninii populations. Consequently, the present allozyme data justify the establishment of
A. lobophylla, but give no support for treating A. wawreana and A. potaninii as a sepa-rate species.
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106.
Paeonia suffruticosa Andrews subsp. spontanea (Rehder) S. G. Haw et L. A.
Lauener ( =P. spontanea = P. jishanensis) has been considered as the wild form of widely
cultivated P. suffruticosa. However, the subspecies differs from the cultivated one in
shape, division and indumentum of leaves and reproductive biology. As a result of extensive
field work, a form with two individuals in Yinping Shan, Caohu, Anhui, and Songxian,
Henan, are found to be extremely similar to P. suffruticosa, but apparently different from
P. jishanensis. The form is considered to be the wild one of P. suffruticosa and described as new: P. suffruticosa subsp, yinpingmudan Hong, K. Y. Pan et Z. W. Xie. 相似文献
107.
A new sesquiterpene, 12,13-di-acetoxyl-l ,4,6,11-eudesmanetetol 1, together with six known com-pounds, was isolated from Michelia yunnanensis. The structures were elucidated on the basis of spectral means. 相似文献
108.
The effects of auxin polar transport inhibitors,9-hydroxy-fluorene-9-carboxylic acid (HFCA);2,3,5-triiodobenzoic acid(TIBA) and trans-cinnamic acid (CA) on leaf pattern formation were investigated with shoots formed from cultured leaf explants of tobacco and cultured pedicel explants of Orychophragmus violaceus,and the seedlings of tobacco and Brassica chinensis,Although the effective concentration varies with the inhibitors used,all of the inhibitors induced the formation of trumpet-shaped and/or fused leaves.The frequency of trumpet-shaped leaf formation was related to the concentration of inhibitors in the medium.Histological observation of tobacco seedlings showed that there was only one main vascular bundle and several minor vascular bundles in normal leaves of the control,but there were several vascular bundles of more or less the same size in the trumpet-shaped leaves of treated ones.These results indicated that auxin polar transport played an important role on bilateral symmetry of leaf growth. 相似文献
109.
采用饲养试验方法,研究了平均体质量为(7.16±0.07)g的大菱鲆(Scophthalmus maximus)幼鱼分别在盐度12、18、24、30和36下饲养60 d后,其鳃Na+-K+-ATPase活力、血清离子浓度、生长激素(GH)、皮质醇激素(COR)、特定生长率(SGR)和饲料效率(FCE)的变化。结果表明:幼鱼鳃Na+-K+-ATPase活力、血清Na+浓度均随盐度的升高而上升,分别在3.48~8.30 U/mg和169.99~180.00 mmol/L之间,其中12盐度组最低,36盐度组最高。幼鱼血清中K+和Cl-浓度分别在2.20~3.47 mmol/L和136.67~142.00 mmol/L之间,各盐度组之间差异不显著。幼鱼血清中GH和COR浓度分别在0.41~1.66 ng/ml和35.33~76.41 ng/ml之间;其中GH在36盐度组最高,12盐度组最低,而COR在12盐度组最高,36盐度组最低。幼鱼SGR和FCE分别在(1.45~2.00)%/d和1.12%~1.38%之间,与盐度的相关性不显著,两者均为12盐度组最低。由此可见,盐度变化显著影响大菱鲆幼鱼鳃Na+-K+-ATPase活力、血清Na+浓度和激素含量。本研究对大菱鲆养殖生理生态条件分析具有重要参考意义,研究结果可为大菱鲆养殖的盐度选择提供理论依据。 相似文献
110.
部分双壳贝类的线粒体遗传方式不同于标准的母系遗传(SMI),被称为双单性遗传现象(DUI)。池蝶蚌(Hyriopsis schlegelii)是淡水双壳贝类,是否存在双单性遗传现象?本文采用普通PCR扩增、SHOT-GUN测序及软件拼接获得了雄性池蝶蚌线粒体基因组(以下简称Hs-mtDNA)全序列,并与本实验室已报道的雌性池蝶蚌线粒体基因组全序列进行差异性分析。结果表明,雄性和雌性Hs-mtDNA全长分别为15961 bp和15939 bp,雄性比雌性长22 bp,雌雄线粒体基因组成与排列顺序一致。各蛋白编码基因的碱基数目均一致,碱基转换率为1.01%~7.34%,颠换率为0.00%~0.62%,氨基酸差异率为0.00%~9.35%;其中,COX1基因变异率为2.72%;COX2基因碱基变异率最高,达7.50%,雄性COX2的3'末端没有出现编码延伸区。雄性12S rRNA基因发生5 bp的碱基转换,差异率为0.6%;16S rRNA基因比雌性长9 bp,碱基差异率仅为1.2%。雌雄tRNA-His均位于H链上,介于COX2与ND3之间,没有出现位置的差异性。雌雄Hs-mtDNA的非编码区共有28个1~393 bp的片段,但未见控制区。在tRNA-Glu与tRNA-Tyr间有一段长393 bp的非编码区存在蛋白质翻译功能,但非雄性特异性蛋白。以COX1基因建立系统进化树,池蝶蚌和三角帆蚌(H.cumingii)聚在一起,而含有双单性遗传现象的无齿蚌属的Pyganodon grandis、小方蚌亚科的Venustaconcha ellipsiformis及小方形蚌属的Quadrula quadrula三者雄性聚为一支,雌性聚为一支。因此,雌雄池蝶蚌线粒体存在一定的差异性,但其差异要比其他具有双单性遗传现象的淡水双壳类小得多,且池蝶蚌线粒体遗传可能不存在双单性遗传现象。 相似文献