Two types of 11 - hsds were identified in vertebrates : whereas 11 - hsd2 , a nad - dependent oxidase , functions exclusively to convert biologically active gc into its inert form , attenuating gc ' s action , 11b - hsd1 was shown to act as a predominant nadp - dependent reductase in tact cells , thus amplifying gc ' s action 在体内，至少存在两种亚型的11 - hsd 。 11 - hsd2主要分布于盐皮质激素( mineralocorticoidhormone , mc )的靶器官，表现为单一的氧化酶活性，与作用底物的亲和力较高，亲和常数在nm水平。
L lp - hsdl ma of i . 5kb was detected in the rna extracted from cult ' ured chorionic trophoblast using northem blot hybridhation method . the expression of ll6 - hsdl wa was induced by treating the chorionic cells with dexamethasone ( l0 - ' , l0 ' m ) for 24h , and the induction was blocked by co - treatinent of the cells with ru486 . these results suggest a gr - mediated effect of glucocorticoid on the rnrna expression and reductase activity of l l 9 - hsd1 人h合成的肌?一加x门’ m ）对培养的绒毛膜滋养层细胞的11p hsdi还原酶活性具有诱导作用，此诱导作用可以被gr阻断剂ru486门0川）所阻断； northern印迹杂交方法进一步证实， dex亦可诱导绒毛膜滋养层细胞11p叫inrna的表达，此诱导作用也可以被ru486门0叫川）所阻断
Especially , apoptin is partially similar with ribonucleotide reductase , uridylate kinase and phosphotriesterase in the amino acid sequence . the similarity between them indicates that apoptin maybe takes part in the signal pathway of apoptosis with phosphotriesterase activity or operates on hnrna with ribonucleotide reductase or uridylate kinase activity 凋亡素与它们的长序列相似性表明，它可能具有磷脂酶活性，在细胞信号通路中起作用；或者具有核糖核苦酸还原酶和尿苦酸激酶活性而对hnrna发挥作用；或者是与其中具有某种活性的蛋白质存在竞争性抑制作用。
This study was to investigate the effects of sulfur dioxide inhalation at different concentrations on some glutathione - related enzymes such as glutathione s - transferase ( gst ) , glucose 6 - phosphate dehydrogenase ( g6pd ) and glutathione reductase ( gred ) in brain , lung , heart , liver , kidney and spleen of mice by the technology of biochemical toxicology . the results were showed as follows , so2 exposure at different concentrations caused the changes of glutathione redox system . moreover , the activities of antioxidative enzymes and the contents of reduced glutathione ( gsh ) were decreased significantly in different tissues at higher concentrations of soa 本研究利用生化毒理学技术研究了不同浓度二氧化硫吸入( 22 2mg m ~ 3 ， 64 3mg m ~ 3 ， 148 23mg m ~ 3 )对纯系昆明小鼠脑、肺、心、肝、肾、脾六种组织的谷胱甘肽还原酶( glutathionereductase ， gred ) 、谷胱甘肽硫转移酶( glutathiones - transferase ， gst )和葡萄糖- 6 -磷酸脱氢酶( glucose6 - phosphmedehydrogenase ， g6pd )活性的影响，结果表明so _ 2吸入使小鼠不同组织的谷胱甘肽氧化还原系统发生了改变，表现为随着so _ 2吸入浓度的增加，该系统中的抗氧化酶活性的显著变化和抗氧化物质水平的显著降低，且存在着组织差异性。
When inadequate n was added , the chloroplast structure in mesophyll cell was damaged in ear leaf , the amount of carbohydrate decreased in mestome sheath , and excessive n - redistribution and n - transportation to grain from vegetative mass appeared , which resulted in earlier leaf senescence . excessive n application led to too high activity of nitrate reductase , excessive vigorous nitrogen metabolism and too much exhaustion of carbohydrate in ear leaf , which resulted in the lack of enough carbohydrate in the lower leaf , meanwhile , the expansive chloroplast grana lamellae in leaf mesophyll cell and starch grain without nuclear in mestome sheath cell was observed , which led to the decrease of chlorophyll content and photosythetic capacity in maize leaf , then the early senescence occured 氮肥用量不足导致穗叶叶肉细胞叶绿体结构性差，维管束鞘细胞碳水化合物累积减少,营养体氮素再分配率大而引起叶片早衰；而过量供氮则导致生长后期硝酸还原酶活性过高，氮素代谢过旺，消耗了大量碳水化合物，以致下位叶不能得到充足的碳水化合物供应而提早脱落，同时叶肉细胞叶绿体片层结构膨胀，呈“肉汁化”特征，维管束鞘细胞淀粉粒大量消耗，无核淀粉粒出现，从而叶片叶绿素含量下降，光合能力降低而出现早衰。
Inhibitors of cyp51 , such as azalanstat ( rs - 2i607 ) and rs - 2i745 , could inhibit the synthesis of ff - mas to decrease the accumulation of ff - mas . inhibitor of a14 - reductase , such as ay9944 - a - 7 , could inhibit the metabolism of ff - mas to increase the accumulation of ff - mas ; and some other reagents , such as nystatin , could combine with the downstream intermediate in the cholesterol biosynthesis pathway to accumulate mas . in this study , we investigated the role of mas by using these reagents to change the level of endogenous ff - mas 抑制cyp51酶的抑制剂，如azalanstat ( rs - 21607 )和rs - 21745等，均能抑制mas的合成，降低mas的积累；而抑制14 -还原酶的抑制剂，如ay9944 - a - 7等，能抑制ff - mas向t - mas的转化而造成ff - mas的积累；还有一些物质，如制霉菌素，能阻止mas向下游的代谢而造成其积累，本文主要通过应用这些物质降低、或增加组织细胞中内源性mas的积累，来研究mas的作用。
Depending on cellular location and function of thioredoxins , there are two thioredoxin systems in high plants , one is nadp / thioredoxin system mainly existing in chloroplast of high plant and eucaryote algae and oxygenic photosynthetic prokaryote , which is composed of nadph , nadph - dependent thioredoxin reductase , thioredoxin - f and thioredoxin - m 在高等植物中，存在两个与硫氧还蛋白密切相关的硫氧还蛋白系统：一个是位于叶绿体中的铁氧还蛋白-硫氧还蛋白系统，该系统中含有两类核基因编码的硫氧还蛋白即f -型trx和m -型trx 。
The purposes of this project were to further analyze the characteristics of their iron efficiency under iron stress , to study the physiological and molecular mechanisms of iron efficiency under iron deficiency in c . junos and m . xiaojinensis , and to analyze the spatial expression model of fcr ( ferric chelate reductase ) gene under iron stress with the hope to cast a new light on iron stress tolerance on the molecular level , to lay solid foundations for cloning fcr gene in c . junos and m . xiaojinensis , and to provide some basic data for creating new rootstocks with excellent complex characters and iron efficiency 本研究通过进一步分析香橙和小金海棠的耐缺铁特性，研究它们耐缺铁的生理原因和分子基础，并通过分析三价铁螯合物还原酶基因的空间表达模式，从分子水平上去探讨植物耐缺铁的原因，为从香橙和小金海棠中克隆三价铁螯合物还原酶基因奠定基础，并为人工创造耐缺铁的果树砧木提供基础研究数据。
