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1.
将水稻(Oryza sativa L.)种子浸于从0到3 mg• L-1不同浓度梯度的GeO2溶液中,测量其生理指标:呼吸强度,可溶性糖含量,淀粉酶活性等。发现在浸种的前期,GeO2对以上各项生理指标均有促进作用,而随着浸种时间的延长,促进逐渐减弱并转为抑制,淀粉酶同功酶电泳则表明,植物体内复杂多样的同功酶系统在一定范围内对GeO2的毒害作用有某种程度的适应与调节能力。  相似文献   

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水稻幼苗冷锻炼过程中钙的效应   总被引:29,自引:0,他引:29  
冷锻炼处理提高了水稻(Oryza sativa L.)幼苗叶片中抗氧化剂(还原型谷胱甘肽,GSH;抗坏血酸,AsA)含量和膜保护酶(超氧化物歧化酶,SOD)的活性,同时也提高了可溶性蛋白质中热稳定蛋白的含量。CaCl2 浸种处理对上述冷锻炼的作用有加强的效果,且明显地提高了过氧化氢酶(CAT)和过氧化物酶(POD)的活性。有无CaCl2 处理的冷锻炼处理均减轻冷胁迫引起的GSH 及AsA 含量、SOD 活性及热稳定蛋白质含量的下降程度,有利于幼苗在恢复过程中GSH、AsA、CAT、SOD、POD及热稳定蛋白质水平迅速回升。结合CaCl2 处理的冷锻炼苗在冷胁迫恢复生长时增长迅速,且苗健壮浓绿,说明CaCl2浸种对冷锻炼处理提高水稻幼苗的抗冷力有明显的促进作用,这与CaCl2 浸种结合冷锻炼能更有效的提高细胞膜保护能力有关  相似文献   

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葡萄糖淀粉酶研究进展   总被引:8,自引:1,他引:7  
葡萄糖淀粉酶研究进展杨依军,李多川,沈崇尧(北京农业大学植物科技学院.北京100094)葡萄糖淀粉酶(GlucoamvlaseE·C3.2.1.3),又称淀粉葡萄糖苷酶(Amyloglucosidase)或γ-淀粉酶(γ-amylase),简称糖化酶...  相似文献   

4.
用2μg/ml玉米素溶液预处理叶绿体或在光活化前于活化液中加入2μg/ml玉米素溶液,观察到玉米素能促进叶绿体膜上耦联因子DTT光活化Mg2+-ATPase及Mg2+GTPase的活力.且对GTPase的促进比例常较ATPase的大些。王米素对OG活化可溶性CF1Mg2+-ATPase活力同样表现出促进作用。用玉米素预处理CF1-β亚基(含微量CF1-α亚基)也观察到它能促进CF1-β亚基催化的Mg2+-ATPase活力。这些结果表明,玉米素在CF1上的作用部位至少有一个在β亚基或α.β亚基交界处调节其催化功能的。  相似文献   

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用2μg/ml玉米素溶液预处理叶绿体或在光活化前于活化液中加入2μg/ml玉米素溶液,观察到玉米素能促进叶绿体膜上耦联因子DTT光活化Mg^2+-ATPase及Mg^2+-GTPase的活力,且对GTPase的促进比例常较ATPase的大些。玉米素对OG活化可溶性CF1Mg^2+-ATPase活力同样表现出促进作用。用玉米素预处理CF1-β亚基(含微量CF1-α亚基)也观察到它促进CF1-β亚基催  相似文献   

6.
钙对水稻幼苗抗冷性的影响   总被引:3,自引:0,他引:3  
CaCl2浸种提高水稻幼苗叶片中结合态钙、内源抗氧化剂(GSH、AsA)含量和膜保护酶(CAT、SOD和POD)活性,也增加可溶性蛋白质中煮沸稳定蛋白质(boiling-stableprotein)的含量。冷胁迫期间,CaCl2并能减少因冷胁迫引起的GSH、AsA含量,CAT、SOD和POD活性以及煮沸稳定蛋白质下降的程度。在恢复期间,经CaCl2处理的幼苗其GSH、ASA、CAT、SOD和POD以及煮沸稳定蛋白质水平均有回升。  相似文献   

7.
莲子超氧物歧化酶的特性分析   总被引:13,自引:0,他引:13  
比较了莲子、豇豆、绿豆、玉米、花生、菜心等种植物种子的胚或胚轴超的歧化酶9SOD)的活性和热稳定性,其中莲子胚轴中SOD活性及耐热性最高。莲子胚轴粗提液中的SOD有Mn ̄SOD和Fe-SOD两种类型,而Fe-SOD耐高温。经100℃处理、硫酸铵沉淀、Sephadex G-100凝胶过滤和DEAE-纤维素柱层析,获得纯化的耐热性强的超氧物歧化酶,纯化酶对PCN不敏感,活性受H2O2抑制,属于Fe-S  相似文献   

8.
活性氧与蛋白多糖的作用及损伤的蛋白多糖对矿化过…   总被引:3,自引:0,他引:3  
本文用凝胶色谱和琼脂糖-聚丙烯酰胺混俣凝胶电泳法比较地研究了活性氧和病区黄腐酸对氨基多糖和蛋白多糖作用,并用恒pH值法研究了完整和受损的PG对矿化的影响。结果表明:1,黄嘌呤-黄嘌呤氧化酶体系对GAG无明显降解作用,只损伤PG的核心蛋白。2,Fe(Ⅱ)-EDTA-H2O2体系同进损伤PG和GAG,并与H2O2浓度和作用时间正相关。3,FA不能直接降解GAG和PG。4,PG能推延磷酸钙成核的诱导期,  相似文献   

9.
研究了箬叶多糖FⅢ-a及其化学修饰物、亚硒酸钠和GSH对Cu2+诱导的低密度脂蛋白氧化修饰的保护作用.其结果表明箬叶多糖、硫酸酯多糖、硒酸酯多糖可显著抑制脂质过氧化产物(TBARS)及荧光物质的生成,彼此之间无明显差异.但对VE的消耗有着不同的保护作用,其顺序是FⅢ-a>S-FⅢ-a>Se-FⅢ-a,并且具有明显的量效关系.硒或GSH对Cu2+诱导的LDL氧化修饰无明显的抑制,但联合使用在0.125mmol/LNa2SeO3和0.2mmol/LGSH及12.5μmol/LNa2SeO3和0.02mmol/LGSH的浓度下能强烈地抑制TBARS的生成,甚至比正常的LDL还要低.但是对VE的消耗只有较弱的保护作用,硒酸酯多糖与此相似.Na2SeO3在0.125mmol/L时可以明显抑制荧光物质的生成.  相似文献   

10.
用PAGEA活性染色分析了D.radiodurans过氧化氢酶(Cat)和起氧化物歧化酶(SOD)。2种同种异型D.radiodurans(R1和Sark)的Cat在电泳带型上存在差异,两者Kat均可分为A、B和C3条带,但各带所占比例明显不同,SOD的分析结果表明,D.radiodurans SOD以Fe^2+和Mn^2+离子的嵌合体形式存在,其中Fe-SOD成分占90%以上。PAGE活性染色法  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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