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911.
912.
Homology modeling, molecular docking, and molecular dynamics simulation have been performed to determine human 15-hydroxyprostaglandin dehydrogenase (15-PGDH) binding with its NAD+ cofactor and prostaglandin E2 (PGE2) substrate. The computational studies have led to a three-dimensional (3D) model of the entire 15-PGDH-NAD+-PGE2 complex, demonstrating the detailed binding of PGE2 with 15-PGDH for the first time. This 3D model shows specific interactions of the protein with the cofactor and substrate in qualitative agreement with available experimental data. Our model demonstrates the PGE2-binding cavity of the protein for the first time. The model further leads to an interesting prediction that the catalytic activity of 15-PGDH should also significantly be affected by Gln148, in addition to the previously known three catalytic residues (Ser138, Tyr151, and Lys155). The reported 3D model of 15-PGDH-NAD+-PGE2 complex might be valuable for future rational design of novel inhibitors of 15-PGDH. 相似文献
913.
新疆部分地区动物Nipah病毒和Hendra病毒感染的调查 总被引:2,自引:0,他引:2
拟建立一步法实时RT-PCR检测Nipah病毒(Nipah virus,NiV)、Hendra病毒(Hendra virus,HeV)的方法,对采集自中国新疆部分地区动物外周血样本进行NiV和HeV检测,以获得我国新疆地区的NiV和HeV的病毒流行病学资料.采用NiV和HeV一步法实时RT-PCR检测方法,对2007年9-12月采集的新疆伊犁河谷地区以及巴音布鲁克草原放养的500匹马、100匹驴和160只犬外周血单个核细胞RNA进行NiV和HeV N基因片段检测.结果:对采集的动物血样本进行NiV和HeV核酸检测,成功进行了一步法实时RT-PCR反应,没有发现阳性样本.初步流行病学研究提示我国新疆部分地区天然牧场放养的动物中可能不存在NiV和HeV感染,该地区出现NiV和HeV爆发的可能性较小. 相似文献
914.
浙江北雁荡山野生蕨类植物资源 总被引:4,自引:0,他引:4
对浙江北雁荡山的蕨类植物进行专题研究。浙江乐清北雁荡山共有蕨类植物147种,隶属于37科70属。蕨类植物物种密度为42.13/100 km2。比西双版纳的密度1.71/100 km2要高。远大于全国蕨类植物密度0.027/1 000 km2,是我国东南沿海蕨类植物物种密度较高的地区之一。按照用途分为药用、食用、观赏和其他用途4大类型。并记录本地常用蕨类的俗名,统计草药市场药用蕨类资源销售量,为进一步开发利用蕨类植物资源提出建议。 相似文献
915.
Scanning electrochemical microscopy (SECM) is useful in probing and characterizing interfaces at high resolution. In this paper, the general principles of this technique are described and several applications of SECM to biological systems, particularly to living cells, is discussed, along with several example systems. Thiodione was detected and monitored electrochemically during the treatment of hepatocytes with cytotoxic menadione. The antimicrobial effects of silver(I) was followed by SECM through bacterial respiration. Living HeLa cells were shown to accumulate ferrocencemethanol (FcMeOH) and generated positive feedback for FcMeOH oxidation that can be further used to monitor the cell viability. Finally, individual giant liposomes, as cell models, with encapsulated redox compounds were successfully probed by SECM. In general SECM has the advantage of very high spatial resolution and versatility, especially for the detection of electroactive substances. 相似文献
916.
茶条槭及其次生代谢产物没食子酸的研究进展 总被引:2,自引:0,他引:2
综述了茶条槭及其次生代谢产物没食子酸的应用价值和目前的研究概况,探讨了利用细胞培养生产没食子酸的前景。 相似文献
917.
A quantitative trait locus,qSE3, promotes seed germination and seedling establishment under salinity stress in rice 总被引:1,自引:0,他引:1
Yongqi He Bin Yang Ying He Chengfang Zhan Yanhao Cheng Jiahui Zhang Hongsheng Zhang Jinping Cheng Zhoufei Wang 《The Plant journal : for cell and molecular biology》2019,97(6):1089-1104
Seed germination is a complex trait determined by both quantitative trait loci (QTLs) and environmental factors and also their interactions. In this study, we mapped one major QTLqSE3 for seed germination and seedling establishment under salinity stress in rice. To understand the molecular basis of this QTL, we isolated qSE3 by map‐based cloning and found that it encodes a K+ transporter gene, OsHAK21. The expression of qSE3 was significantly upregulated by salinity stress in germinating seeds. Physiological analysis suggested that qSE3 significantly increased K+ and Na+ uptake in germinating seeds under salinity stress, resulting in increased abscisic acid (ABA) biosynthesis and activated ABA signaling responses. Furthermore, qSE3 significantly decreased the H2O2 level in germinating seeds under salinity stress. All of these seed physiological changes modulated by qSE3 might contribute to seed germination and seedling establishment under salinity stress. Based on analysis of single‐nucleotide polymorphism data of rice accessions, we identified a HAP3 haplotype of qSE3 that was positively correlated with seed germination under salinity stress. This study provides important insights into the roles of qSE3 in seed germination and seedling establishment under salinity stress and facilitates the practical use of qSE3 in rice breeding. 相似文献
918.
Yang Zhan 《Anthropological Forum》2019,29(2):153-171
ABSTRACTIn contemporary China, migrant workers have gathered in urban villages and formed communities of their own. The regulative power of the state has not fully penetrated these enclaves, thus creating opportunities for NGOs to shoulder many of the ongoing welfare responsibilities. The primary goal of this study was to explore how NGO service projects can generate a new type of disciplinary power through give-and-take practices. I argue that service projects allow the givers to transform their economic power and social resources into political power, through which social inequality is obscured, legitimised, and translated into the delivery of ‘love’, ‘caring’ and ‘compassion’. Such political power also delivers middle-class values and lifestyles to rural migrants, who feel obligated to transform their subjectivities in order to reciprocate. 相似文献
919.
甜菜纤维的制备及其性质 总被引:2,自引:0,他引:2
甜菜纤维的制备及其性质樊志和周人纲王占武李晓芝韩炜(河北省农林科学院农业物理生理生化研究所,石家庄050051)Apracticalpreparationandcharacterizationofdietaryfiberfromsugar┐beetp... 相似文献
920.