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1.
Kai-For Mo 《Carbohydrate research》2009,344(4):439-1494
The synthesis of laminarahexaose is described. NMR studies of several of the intermediates leading to the β-1,3-glucan show anomalously small coupling constants for some of the C-1 hydrogens. An X-ray structure for the protected hexasaccharide shows that the small coupling constants are due to some of the glucopyranose rings adopting a twist-boat conformation. The X-ray studies also explain other unexpected NMR observations. 相似文献
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Yao Chen Jie Zhu Jun Mo Hongyu Yang Xueyang Jiang Hongzhi Lin 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):290-302
Small molecule cholinesterases inhibitor (ChEI) provides an effective therapeutic strategy to treat Alzheimer’s disease (AD). Currently, the discovery of new ChEI with multi-target effect is still of great importance. Herein, we report the synthesis, structure–activity relationship study and biological evaluation of a series of tacrine-cinnamic acid hybrids as new ChEIs. All target compounds are evaluated for their in vitro cholinesterase inhibitory activities. The representatives which show potent activity on cholinesterase, are evaluated for the amyloid β-protein self-aggregation inhibition and in vivo assays. The optimal compound 19, 27, and 30 (human AChE IC50?=?10.2?±?1.2, 16.5?±?1.7, and 15.3?±?1.8?nM, respectively) show good performance in ameliorating the scopolamine-induced cognition impairment and preliminary safety in hepatotoxicity evaluation. These compounds deserve further evaluation for the development of new therapeutic agents against AD. 相似文献
4.
Shi Fenghua Tan Muxiu Mo Qiaocheng Chen Xiaoying Zhao Yimin Guo Xiaoyun Jiang Ni 《Journal of plant biochemistry and biotechnology.》2020,29(3):528-538
Journal of Plant Biochemistry and Biotechnology - The dried buds of Lonicera hypoglauca Miq. have antipyretic, antidotal and anti-inflammatory properties and as Flos lonicerae are widely used in... 相似文献
5.
胚乳性状的遗传模型和世代平均数 总被引:25,自引:7,他引:18
谷类作物的胚乳是三倍体组织,胚乳性状受3N遗传控制。本文分析了胚乳性状的遗传特征,建立了相应的遗传模型,推导了世代群体的平均数分量,并提出了研究胚乳性状基因效应的一些简单的交配设计。 相似文献
6.
The heart as an endocrine organ 总被引:1,自引:0,他引:1
Modern data on atrial natriuretic factor (ANF) are presented. Synthesis of this factor, its storage and release from cardiac atria are described. The role of ANF in the body fluid volume regulation and blood pressure homeostasis is discussed. ANF is regarded as a circulating hormone. 相似文献
7.
在自生异养条件下,旋扭山绿豆根瘤菌MXDI6菌株的氢酶诱导表达受气相、pH值、镍等因子影响:氢酶表达的最适氧浓度为4%,最适氢浓度为15%,二氧化碳没有明显影响;氢酶表达的pH值以5.0—6.0为宜;0.5μmol/LNiCl2明显促进吸氢活性,但镍浓度大于1μmol/L则抑制吸氢活性. 相似文献
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Francesco Ricci Kshitij Tandon Maria Moßhammer Ellie H.-J. Cho Linda L. Blackall Michael Kühl Heroen Verbruggen 《Environmental microbiology》2023,25(8):1505-1521
The coral skeleton harbours a diverse community of bacteria and microeukaryotes exposed to light, O2 and pH gradients, but how such physicochemical gradients affect the coral skeleton microbiome remains unclear. In this study, we employed chemical imaging of O2 and pH, hyperspectral reflectance imaging and spatially resolved taxonomic and inferred functional microbiome characterization to explore links between the skeleton microenvironment and microbiome in the reef-building corals Porites lutea and Paragoniastrea benhami. The physicochemical environment was more stable in the deep skeleton, and the diversity and evenness of the bacterial community increased with skeletal depth, suggesting that the microbiome was stratified along the physicochemical gradients. The bulk of the coral skeleton was in a low O2 habitat, whereas pH varied from pH 6–9 with depth. Physicochemical gradients of O2 and pH of the coral skeleton explained the β-diversity of the bacterial communities, and skeletal layers that showed O2 peaks had a higher relative abundance of endolithic algae, reflecting a link between the abiotic environment and the microbiome composition. Our study links the physicochemical, microbial and functional landscapes of the coral skeleton and provides new insights into the involvement of skeletal microbes in the coral holobiont metabolism. 相似文献
10.
Fluorescence nanosensors based on functional nucleic acids have been explored as a powerful sensing platform for disease-relevant miRNAs. This work developed a new hybrid nanosensor (Zr-B) through coordination-driven self-assembly of Zr ions and beacons. The prepared nanosensor exhibited high loading efficiency of beacons and could achieve sensitive and specific detection for miRNAs. The hybrid nanosensor could transfer beacons into living cells efficiently and maintain high stability and biocompatibility in the biological environment, achieving effective miRNA fluorescence imaging in living cells. Therefore, the resultant nanosensor holds potential for applications in disease diagnostics. 相似文献