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991.
SONG Guo-bin XI Guo-ping LI Yan-hua LI Jia-shan LIU Jian-chun CHAI Zhi XIAO Bao-guo ZHANG Guang-xian MA Cun-gen 《园艺学报》2017,33(12):2113-2120
AIM: To explore the neuroprotective effect of fasudil combined with bone marrow-derived neural stem cells (BM-NSCs) on the mice with experimental autoimmune encephalomyelitis (EAE). METHODS: Female C57BL/6 mice (8~10 weeks old, n=32) were immunized with myelin oligodendrocyte glycoprotein 35-55 (MOG35-55) to establish chronic EAE model. The mice were randomly divided into control (ddH2O) group, fasudil group, BM-NSCs group, and fasudil+BM-NSCs group. The clinical score and body weight were recorded every other day. The expression of neurotrophic factors was determined by immunofluorescence staining. RESULTS: In comparison with ddH2O group, fasudil combined with BM-NSCs delayed onset and ameliorated severity of EAE. The numbers of brain-derived neurotrophic factor, glial cell-derived neurotrophic factor, nerve growth factor, neurotrophin-3 and ciliary neurotrophic factor positive cells in fasudil group, BM-NSCs group and fasudil+BM-NSCs group were all increased in various extents. In particularly, the expression of these neurotrophic factors in fasudil+BM-NSCs group was significantly higher than that in the mice treated with fasudil or BM-NSCs alone (P<0.01). CONCLUSION: Fasudil combined with BM-NSCs promotes the expression of neurotrophic factors and improves microenvironment of central nervous system, thus playing a positive role in neural restoration and regeneration through a synergistic and superimposed effect. 相似文献
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AIM: To evaluate specific metabolomics profiles in the serum of patients with chronic mountain sickness (CMS) and to explore the potential metabolic biomarkers in the native Tibetans living on the Qinghai-Tibet Pla-teau.METHODS: A gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) approach as a metabolomics technique was used to evaluate metabolic differences. The native Tibetan CMS patients (n=10) and healthy Tibetan controls (n=10) were enrolled from YuShu in Qinghai province in this study. The serum samples were collected and analyzed by GC-TOF-MS coupled with a series of multivariate statistical analyses such as principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA).RESULTS: The intergroup differences between CMS patients and control subjects have been observed. A list of differential metabolites and several top altered metabolic pathways have been identified. The levels of fumaric acid, an intermediate in the tricarboxylic acid (TCA) cycle, and inosine were highly upregulated in the CMS patients, suggesting a greater effort to hypoxic adaptation in high elevation area. Other differential metabolites, such as methyl phosphate, 2-ketoadipate, lyxose and phytanic acid were also identified. Importantly, the differential metabolites possessed higher area under the ROC curve (AUC) values, indicating an excellent clinical ability for the prediction of CMS. Increased levels of amino acids (isoleucine, glycine, serine, L-cysteine, citrulline and trimethyllysine) were detected in CMS group, yet significantly decreased levels of sulfuric acid, oxamic acid, lyxose and glutamine were also detected in CMS group than those in control group. At the same time, the levels of ribose and glucose-1-phosphate were markedly elevated in CMS group (P<0.05).CONCLUSION: The metabolic activities are significantly altered in the serum of CMS patients. High altitude hypoxia may act on the disturbed glucose metabolism and amino acid metabolism in part of the Tibetan triggered by CMS. 相似文献
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以4年生"玫瑰香"葡萄为试材,设置改良霍格兰营养液0.5、1.0、1.5倍3个浓度,探讨了不同养分供应量对"玫瑰香"葡萄树体营养生长、光合特性和果实品质的影响。结果表明:不同营养液浓度处理下的新梢长度、粗度和主干基部直径均表现为1.5倍1.0倍0.5倍,0.5倍浓度和1.0倍浓度处理下的净光合速率高于1.5倍浓度,果实的可溶性固形物和花色苷含量均表现为1.0倍浓度处理最大,而可滴定酸含量为1.5倍0.5倍1.0倍。从整体情况来看,适当提高营养液浓度(1.0倍),有利于增加可溶性固形物、降低可滴定酸含量和果实的提前着色;营养液浓度过高时,可溶性固形物含量反而下降,可滴定酸含量增加,不利于提高果实品质和果实风味物质的形成。 相似文献
996.
以杜梨叶片为试材,采用同源序列和RACE技术克隆了梨ARRO(adventitious rooting related oxygenase)基因,并进行了基因的生物信息学和时空表达分析,以期对梨属植物不定根产生研究提供帮助。结果表明:PbARRO?1基因开放读码框全长831bp,编码276个氨基酸,相对分子量为30.535 9kD,等电点pI为5.53;推导氨基酸序列同源性分析显示该基因与苹果、梅花、毛果杨等具有较高同源性,其中苹果达到92%。荧光实时定量PCR分析表明,该基因在秋子梨根、茎、叶中均有表达,叶片中表达量初期较高,后期较低;茎中表达量则呈现先升高后降低的趋势,在第15天达到峰值,推测PbARRO-1基因与茎上不定根的形成密切相关。 相似文献
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基于Web of Science的土壤微生物研究文献国际发展态势分析 总被引:2,自引:0,他引:2
在文献调研、专家咨询和文献计量分析的基础上,对国际土壤微生物研究的发展历程进行了回顾,利用文献计量学方法分析了土壤微生物学研究的主要国家和机构状况,分析了近年来相关研究的学科分布以及热点主题内容,分析了国际土壤微生物研究的发展态势和挑战。结果表明:国际土壤微生物研究的学科分布主要集中在土壤科学、环境科学,而且土壤科学、环境科学、生态学、微生物学、农学生物技术应用微生物学的文献数量达到文献总量75.04%,表明这几个学科领域是土壤微生物研究的前沿热点;热点主题主要集中在土壤微生物多样性、生物量、有机质、土壤碳等方面,总结了这些领域的发展趋势和重点研究方向,并根据分析结果,对我国土壤微生物学领域采取的措施、今后发展的方向提出了建议。 相似文献
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