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31.
In the present communication, we report remarkably elevated levels of xanthine oxidase activity in the blood of the patients with myocardial infarction when compared to age and sex matched healthy persons. Highly significant increase of malondialdehyde, serving as an index of lipid peroxidation and thus free radical mediated damage, has also been found in the patients. We propose the measurement of the blood levels of xanthine oxidase, a very simple, reliable and less time consuming method as an indicator of myocardial infarction.  相似文献   
32.
利用圆二色光谱和荧光光谱法研究细胞色素b5蛋白在温度和酸度变化过程中蛋白质构象的情况。发现在升高温度和降低pH值的情况下,细胞色素b5蛋白的荧光吸收峰均有下降的趋势,表明色氨酸残基环境的极性增加而疏水性降低,细胞色素b5内部的疏水结构有所瓦解,构象发生改变。升高温度时,圆二色谱的谱图中α-helix含量下降,说明细胞色素b5的二级结构发生变化,稳定性降低。外部条件的改变,可使细胞色素b5的构象发生变化,分子内部极性增强,α-螺旋含量下降。  相似文献   
33.
DirectElectronTransferReactionsofGlucoseOxidaseandD┐AminoAcidOxidaseataGlasyCarbonElectrodeinOrganicMediaWeiJianjunQinYiqinLi...  相似文献   
34.
运用分子动力学模拟与路径通道分析法研究细胞色素c(Cyt c)在银纳米团簇表面上的主要吸附驱动力、构象变化和电子转移的耦合矩阵元。结果表明,银纳米团簇表面电荷对电子转移至关重要。不带电的银纳米团簇有利于细胞色素c的吸附,且容易发生电子转移反应。  相似文献   
35.
The lysyl oxidase (LOX) family encodes the copper-dependent amine oxidases that play a key role in determining the tensile strength and structural integrity of connective tissues by catalyzing the crosslinking of elastin or collagen. Estrogen may upregulate the expression of LOX and lysyl oxidase-like 1 (LOXL1) in the vagina. The objective of this study was to determine the effect of estrogen on the expression of all LOX family genes in the urogenital tissues of accelerated ovarian aging mice and human Ishikawa cells. Mice and Ishikawa cells treated with estradiol (E2) showed increased expression of LOX family genes and transforming growth factor β1 (TGF-β1). Ishikawa cells treated with TGF-β1 also showed increased expression of LOX family genes. The Ishikawa cells were then treated with either E2 plus the TGF-β receptor (TGFBR) inhibitor SB431542 or E2 alone. The expression of LOX family genes induced by E2 was reduced in the Ishikawa cells treated with TGFBR inhibitor. Our results showed that E2 increased the expression of the LOX family genes, and suggest that this induction may be mediated by the TGF-β signal pathway. E2 may play a role in regulating the expression of LOX family genes.  相似文献   
36.
本文利用生物信息学软件分析了23种昆虫线粒体Cytb基因序列的同源性,并构建分子进化树。序列同源性分析表明:蚕蛾科昆虫间的序列相似性较高,其次是螟蛾科,再次是大蚕蛾科;意大利蜜蜂与其它22种序列的相似性最低,东亚飞蝗与其它22种序列的相似性也较低。分子进化树分析表明:膜翅目的意大利蜜蜂与作为外群的斑节对虾聚为一支(A群);直翅目的东亚飞蝗与鳞翅目昆虫聚为一支(B群),双翅目昆虫聚为一支(C群)。  相似文献   
37.
The activities of enzymes responsible for lignification in pepper, pre-inoculation with arbuscular mycorrhizal (AM) fungus ofGlomus intraradices and/or infection with pathogenic strain ofPhytophthora capsici, and the biological control effect ofG. intraradices on Phytophthora blight in pepper were investigated. The experiment was carried out with four treatments: (1) plants pre-inoculated withG. intraradices (Gi), (2) plants pre-inoculated withG. intraradices and then infected withP. capsici (Gi+Pc). (3) plants infected withP. capsici (Pc), and (4) plants without any of the two microorganisms (C). Mycorrhizal colonization rate was reduced by about 10% in pathogen challenged plants. Root mortality caused by infection ofP. capsici was completely eliminated by pre-inoculation with antagonisticG. intraradices. On the ninth day after pathogen infection, Peroxidase (POD) activity increased by 116.9% in Pc-treated roots but by only 21.2% in Gi+Pc-treated roots, compared with the control, respectively. Polyphenol oxidase (PPO) and Phenylalanine ammonia-lyase (PAL) activities gradually increased during the first 3 d and dramatically decreased in Pc-treated roots but slightly decreased in Gi+Pc-treated roots, respectively. On the ninth day after pathogen infection, PPO and PAL decreased by 62.8% and 73.9% in Pc-treated roots but by only 19.8% and 19.5% in Gi+Pc-treated roots, compared with the control, respectively. Three major POD isozymes (45000, 53000 and 114000) were present in Pc-treated roots, while two major bands (53000 and 114000) and one minor band (45000) were present in spectra of Gi+Pc-treated roots, the 45000 POD isozyme was significantly suppressed byG. intraradices, suggesting that the 45000 POD isozyme was induced by the pathogen infection but not induced by the antagonisticG. intraradices. A 60000 PPO isozyme was induced in Pc-treated roots but not induced in Gi+Pc-treated roots. All these results showed the inoculation of antagonisticG. intraradices alleviates root mortality, activates changes of lignification-related enzymes and induces some of the isozymes in pepper plants infected byP. capsici. The results suggested thatG. intraradices is a potentially effective protection agent againstP. capsici. Project supported by Korea Science and Engineering Foundation (KOSEF) through the Agricultural Plants Stress Research Center (APSRC) at Chonnam National University, Korea  相似文献   
38.
选取野桑蚕和5个中系家蚕地理品种为实验材料,采用PCR(polymerase chain reaction)产物直接测序法,获得细胞色素b(cytochrome b,Cyt b)基因5′端591bp的核苷酸序列。对6个核苷酸序列进行变异性分析,并分别利用DNASTAR和PHYLIP软件构建分子进化树。结果表明:所选中系家蚕品种间的序列变异性很低;家蚕品种沿河-1和楚雄是独立起源的;家蚕品种德清-1和延吉的亲缘关系较近。  相似文献   
39.
The effects of the alcoholic extract of the flowers ofIxora coccinea were studied on some of the antioxidant enzymes in dead space wounds created in rats. Increases in the tensile strength of the wound and in the level of lysyl oxidase, the crucial enzyme for collagen maturation, were observed indicating a definite prohealing action. In addition, a highly significant increase in the levels of catalase, glutathione peroxidase and glutathione reductase was observed in the drug-treated group. Thus, the gain in tensile strength may be attributed not only to the better cross-linking but also to the antioxidant properties of the drug.  相似文献   
40.
多酚氧化酶是一种氧化还原酶,主要与植物色素的生成及其产品的色变有关,有利于水果或作物营养价值的保持.本论文以绿豆嫩叶多酚氧化酶粗提液为研究对象,采用不同条件下的磁感应强度的稳恒磁场处理,研究其对多酚氧化酶活性的影响.实验过程分别选用不同的磁感应强度以及时间处理,结果表明:在测酶活性过程中,酶与底物反映很快,1min时底物已全部反应,吸光度也不再增加.在反应初,对照组吸光度为0.8822.处理条件为1.6T15min时,磁场处理对PPO活性促进作用最明显,吸光度为1.0023.反应初始阶段完成以后,对照组酶活力为0.668U.处理条件为0.8T10min时,磁场处理对PPO活性促进作用最明显,酶活力为0.781U.  相似文献   
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