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31.
Human alpha-galactosidase A (alpha-Gal A) is the lysosomal glycohydrolase that cleaves the terminal alpha-galactosyl moieties of various glycoconjugates. Overexpression of the enzyme in Chinese hamster ovary (CHO) cells results in high intracellular enzyme accumulation and the selective secretion of active enzyme. Structural analysis of the N -linked oligosaccharides of the intracellular and secreted glycoforms revealed that the secreted enzyme's oligosaccharides were remarkably heterogeneous, having high mannose (63%), complex (30%), and hybrid (5%) structures. The major high mannose oligosaccharides were Man5-7GlcNAc2 species. Approximately 40% of the high mannose and 30% of the hybrid oligosaccharides had phosphate monoester groups. The complex oligosaccharides were mono-, bi- , 2,4-tri-, 2,6-tri- and tetraantennary with or without core-region fucose, many of which had incomplete outer chains. Approximately 30% of the complex oligosaccharides were mono- or disialylated. Sialic acids were mostly N -acetylneuraminic acid and occurred exclusively in alpha2, 3-linkage. In contrast, the intracellular enzyme had only small amounts of complex chains (7.7%) and had predominantly high mannose oligosaccharides (92%), mostly Man5GlcNAc2 and smaller species, of which only 3% were phosphorylated. The complex oligosaccharides were fucosylated and had the same antennary structures as the secreted enzyme. Although most had mature outer chains, none were sialylated. Thus, the overexpression of human alpha-Gal A in CHO cells resulted in different oligosaccharide structures on the secreted and intracellular glycoforms, the highly heterogeneous secreted forms presumably due to the high level expression and impaired glycosylation in the trans- Golgi network, and the predominately Man5-7GlcNAc2 cellular glycoforms resulting from carbohydrate trimming in the lysosome.   相似文献   
32.
Ten healthy adult Kilis goat mesenteric lymph nodes were used to examine the general structure of lymph nodes, lymphocytes, plasma cells, reticular cells and reticular fibers using histological methods. We also detected T lymphocytes using anti-CD3 [SP7], anti-CD4 [74-12-4], mouse anti-bovine CD4 [CC30] and mouse anti-bovine CD8 [CC63] monoclonal antibodies (mAb); and B lymphocytes using anti-CD79a [HM57] mAb, macrophages using anti-macrophage [MAC387] mAb and follicular dendritic cells using anti-S100 polyclonal antibody (pAb). The distribution of these cells also was studied. Although the primer antibodies we used for CD3, CD8, CD79a, MAC387 and S100 worked well, the primer antibodies for CD4 were ineffective for paraffin embedded goat lymph nodes.  相似文献   
33.
Soybean isoflavones play diverse roles in human health, including cancers, osteoporosis, heart disease, menopausal symptoms and pabulums. The objective of this study was to identify the quantitative trait loci (QTL) associated with the isoflavones daidzein (DC), genistein (GeC), glycitein (GlC) and total isoflavone contents (TIC) in soybean seeds. A population of 184 F21:0 recombinant inbred lines derived from a ‘Xiaoheidou’ בGR8836’ cross was planted in pot and field conditions to evaluate soybean isoflavones. Twenty-one QTL were detected by composite interval mapping. Several QTL were associated with the traits for DC, GeC, GlC and TIC only. QDGeGlTIC4_1 and QDGlTIC12_1 are reported first in this study and were associated with the DC, GeC, GlC and TIC traits simultaneously. The QTL identified have potential value for marker-assisted selection to develop soybean varieties with desirable isoflavone content.  相似文献   
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采用硅胶柱层析色谱和重结晶方法对榕树须95%乙醇提取物进行分离,得到8化合物,通过理化性质和波谱技术分别鉴定为:α-香树脂醇乙酸酯(1),羽扇豆醇乙酸酯(2),木栓酮(3),木栓醇(4),正三十五烷醇(5),白桦酯酸(6),β-谷甾醇(7)和豆甾-4-烯-6β-羟基-3-酮(8)。除化合物6外,其余化合物均为首次从该植物中分离得到。  相似文献   
36.
在蒙古南部Lugiingol剖面卢金格尔(Lugiingol)组下部发现牙形刺Mesogondolell aidahoensis,该地层应归入下二叠统空谷阶,而不是像以前那样归入上二叠统。  相似文献   
37.
本文以雨生红球藻皂化产物中虾青素含量为评价指标,对β-环糊精包合雨生红球藻皂化产物可行性进行了实验研究。试验结果表明,当雨生红球藻粉在优选的实验条件下皂化产物经β-环糊精包合后,HPLC检测主要成分组成未见明显变化,包合率可达到90%。于温度40℃,湿度75%条件下进行稳定性加速实验,结果表明,经皂化后包合物中虾青素稳定性较好,达到了药物和保健食品原料的稳定性要求,说明该方法可行。  相似文献   
38.
本文检测了用基因芯片筛选出水稻种子被低能N+辐照后引起的差异表达的ABA代谢和信号途径相关基因。结果显示,与ABA合成相关的ZDS、Lyc-β、ZEP、NCED、SDR这五种酶的基因表达量均为上调;受ABA调控的的H+-ATPase、NR、Rubisco的基因表达变化显著;ABA依赖的逆境应答蛋白DREB和ASR的表达量上调;受ABA信号转导调控的蛋白LEA的表达量下调,GAD和P5CS的表达量上调。这些结果表明,6×1017N+·cm-2剂量的辐照可能促进了ABA的合成和幼苗气孔的开放,同时促进了ABA信号系统并激活或抑制了一些相关基因的表达。  相似文献   
39.
The aphid subfamily Hormaphidinae is a good candidate for the study of the evolution of insect – plant relationships. Most hormaphidine species depend on woody primary host plants and woody or herbaceous secondary host plants, and represent high host specificity, especially to their primary hosts. No detailed molecular phylogeny of Hormaphidinae has been reported, and the taxonomic positions of some taxa in this group remain unclear. To reconstruct major phylogenetic relationships and to understand the evolution of host association patterns for major lineages, we present the first detailed molecular phylogeny of Hormaphidinae, as inferred from nuclear and mitochondrial DNA sequences, using maximum parsimony, maximum likelihood, and Bayesian methods. The monophyly of Hormaphidinae and its three traditional tribes was supported, and a sister relationship between Hormaphidini and Nipponaphidini was suggested. Most inner relationships within tribes were also supported, and some novel relationships were revealed. Two subtribes of Cerataphidini are proposed. Divergence times estimated using a Bayesian approach indicate that tribal diversifications occurred during the Late Cretaceous and were coincident with the appearance of their primary host plants. The current pattern of secondary host association for the three tribes may have evolved in different time ranges. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 73–87.  相似文献   
40.
1. Although potentially vulnerable to predators, the offspring of subsocial insects are effectively protected by their parent(s). The female giant water bug Kirkaldyia deyrolli lays its egg masses on the vegetation above the water surface in aquatic environments and the males supply the eggs with water and guard them against cannibalistic females until hatchling dispersal. Field observations showed that egg masses are attacked by ants if the attending males are not present. 2. Laboratory experiments were conducted to evaluate the effects of paternal care by K. deyrolli against the ant Tetramorium tsushimae by means of four treatments: attending male with ant approach (WM‐WA); no attending male with ant approach (NoM‐WA); attending male without ant approach (WM‐NoA); and no attending male without ant approach (NoM‐NoA). 3. The rate of offspring survival was lower in the NoM‐WA group (45.3%) than in any other group, which showed similar offspring survival (WM‐WA = 80.4%, WM‐NoA = 75.1%, NoM‐NoA = 80.3%). Moreover, there were a total of 44 interactions between the attending male and ants in WM‐WA, and of these, a chemical compound was released by the attending male four times; this probably deterred ants from attacking because the ants went back to their colony. 4. In conclusion, the attending male can protect its eggs from ant predators and its care has an important role. To the best of the authors' knowledge, this is the first report of Lethocerinae males protecting their egg masses from ants by means of physical and chemical defence.  相似文献   
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