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1.
为了解汉江上游干支流沉积物细菌多样性以及确定性过程和随机性过程在沉积物细菌群落构建过程中的相对重要性,基于Illumina高通量测序技术,分析了环境因子对细菌群落组成的影响,采用非度量多维尺度(NMDS)排序探究了季节之间沉积物细菌群落的差异,并结合中性群落模型和标准化随机率量化了确定性过程和随机过程对群落构建的影响。结果表明:汉江上游及其支流细菌群落主要由变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、蓝藻门(Cyanophyta)、浮霉菌门(Planctomycetes)和酸杆菌门(Acidobacteria)等组成;细菌群落在不同季节有显著差异;地理距离和环境因子对细菌群落结构影响较小,确定性过程并未在细菌群落组成中起到主导作用;随机过程很大程度上影响了群落在秋季和春季的组成,是沉积物细菌群落构建的主导因素。  相似文献   
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Inhibition of PSD-95 has emerged as a promising strategy for the treatment of ischemic stroke, as shown with peptide-based compounds that target the PDZ domains of PSD-95. In contrast, developing potent and drug-like small molecules against the PSD-95 PDZ domains has so far been unsuccessful. Here, we explore the druggability of the PSD-95 PDZ1-2 domain and use fragment screening to investigate if this protein is prone to binding small molecules. We screened 2500 fragments by fluorescence polarization (FP) and validated the hits by surface plasmon resonance (SPR), including an inhibition counter-test, and found four promising fragments. Three ligand efficient fragments were shown by 1H,15N HSQC NMR to bind in the small hydrophobic P0 pockets of PDZ1-2, and one of them underwent structure-activity relationship (SAR) studies. Overall, we demonstrate that fragment screening can successfully be applied to PDZ1-2 of PSD-95 and disclose novel fragments that can serve as starting points for optimization towards small-molecule PDZ domain inhibitors.  相似文献   
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目的检测収酵食品倒笃菜中细菌和真菌菌群结构。方法利用第二代高通量测序对倒笃菜中的真菌和细菌菌群结构迚行测定分析。结果检测出倒笃菜产品中,细菌群落中占主要地位为假单胞菌属(Pseudomonas)、拟杆菌属(Bacteroides)和Faecalibacterium属,分别占比例为11.4%、9.3%和8.9%,而对収酵起至兲重要的芽孢乳杆菌属(Lactobacillus)仅占比例为1.1%。倒笃菜中真菌群落中占主要地位的真菌菌属为曲霉属(Aspergillus),占比为88.8%,而其余真菌占比仅为11.2%。其中,曲霉真菌属中存在可以产生真菌毒素的黄曲霉菌(A.flavus)、寄生曲霉菌(A.parasiticus)等。结论结果表明传统腌制倒笃菜产品中可能会存在一定的致病细菌与可产真菌毒素的真菌,从而有引起食品安全问题的风险,因此,应迚一步对倒笃菜微生物的安全性迚行深入检测分析。  相似文献   
5.
Tuberculosis is one of the leading cause of death in the world, mainly due to the increasing number of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) strains. Factors such as the HIV pandemic contribute further. Also, the ineffectiveness of the chemotherapy in current use increases the mortality rate. Therefore, new and repurposed antituberculosis drugs are urgently needed for the treatment of MDR-TB, and riminophenazines are among those drugs that are being reinvestigated for their potential in the treatment of TB. This review delivers a brief historical account of riminophenazines, their general synthesis, mechanisms of action, and their physicochemical properties. The discussion is limited to those studies that investigated the activity of these compounds as antituberculosis agents. Given their unique properties, this review will be of great significance in giving direction towards the design and development of new riminophenazine analogues.  相似文献   
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We define the emerging research field of applied data science as the knowledge discovery process in which analytic systems are designed and evaluated to improve the daily practices of domain experts. We investigate adaptive analytic systems as a novel research perspective of the three intertwining aspects within the knowledge discovery process in healthcare: domain and data understanding for physician- and patient-centric healthcare, data preprocessing and modelling using natural language processing and (big) data analytic techniques, and model evaluation and knowledge deployment through information infrastructures. We align these knowledge discovery aspects with the design science research steps of problem investigation, treatment design, and treatment validation, respectively. We note that the adaptive component in healthcare system prototypes may translate to data-driven personalisation aspects including personalised medicine. We explore how applied data science for patient-centric healthcare can thus empower physicians and patients to more effectively and efficiently improve healthcare. We propose meta-algorithmic modelling as a solution-oriented design science research framework in alignment with the knowledge discovery process to address the three key dilemmas in the emerging “post-algorithmic era” of data science: depth versus breadth, selection versus configuration, and accuracy versus transparency.  相似文献   
8.
窖泥质量对浓香型白酒的发酵具有重要影响。一般来说,窖龄越大,窖泥质量越好,酿酒质量越好。近年来,以提高窖泥质量、促进窖泥老熟为导向的研究成为热点。本文按照从基础理论到改良应用研究的逻辑顺序,参考相关文献资料,就窖泥菌群结构、菌种功能及人工窖泥改良三方面进行综述。在时间维度上,随窖龄增加,窖泥原核菌群多样性逐渐增加,菌群结构逐渐趋于稳定(老熟),而真核菌群多样性逐渐减少,甚至消失。在空间分布上,池底窖泥原核菌群多样性大于池壁泥,而真核菌群相反,且其在池底老窖泥中趋于消失状态。窖泥中一些菌种参与己酸合成,如克氏梭菌(Clostridium kluyveri)和Ruminococcaceae CPB6,随窖泥老熟,窖泥菌群逐渐形成了完整的代谢网络。人工窖泥改良可以有效促进窖泥菌群的老熟。通过本综述,为进一步的窖泥菌群理论及应用研究提供了新思路。  相似文献   
9.
Fenretinide (4-HPR) is a synthetic derivative of all-trans-retinoic acid (ATRA) characterised by improved therapeutic properties and toxicological profile relative to ATRA. 4-HPR has been mostly investigated as an anti-cancer agent, but recent studies showed its promising therapeutic potential for preventing metabolic syndrome. Several biological targets are involved in 4-HPR's activity, leading to the potential use of this molecule for treating different pathologies. However, although 4-HPR displays quite well-understood multitarget promiscuity with regards to pharmacology, interpreting its precise physiological role remains challenging. In addition, despite promising results in vitro, the clinical efficacy of 4-HPR as a chemotherapeutic agent has not been satisfactory so far. Herein, we describe the preparation of a library of 4-HPR analogues, followed by the biological evaluation of their anti-cancer and anti-obesity/diabetic properties. The click-type analogue 3 b showed good capacity to reduce the amount of lipid accumulation in 3T3-L1 adipocytes during differentiation. Furthermore, it showed an IC50 of 0.53±0.8 μM in cell viability tests on breast cancer cell line MCF-7, together with a good selectivity (SI=121) over noncancerous HEK293 cells. Thus, 3 b was selected as a potential PET tracer to study retinoids in vivo, and the radiosynthesis of [18F] 3b was successfully developed. Unfortunately, the stability of [18F] 3b turned out to be insufficient to pursue imaging studies.  相似文献   
10.
不同含量低污染水对人工湿地中细菌的影响研究   总被引:1,自引:0,他引:1  
探究水平流人工湿地(HFCW)系统处理低污染水过程中,相同COD/ρ(TN)下不同碳氮含量对细菌群落结构的影响。结果表明,进水为较高碳氮含量的HFCW(HF1)和进水为较低碳氮含量的HFCW(HF2)对COD和TN的去除效率具有一定的差异,HF1和HF2对COD的去除效率分别为48.26%和28.89%,对TN的去除率分别为79.06%和81.87%。HF1中细菌的丰富度和多样性均高于HF2,HF1中富集的优势细菌为Chloroflexaceae、Comamonadaceae和Rhodocyclaceae,均具有异养反硝化功能,HF2中富集的优势细菌为Xanthomonadaceae和Rhodocyclaceae,其中Xanthomonadaceae具有自养反硝化功能。COD、NH4^+-N和NO3^--N对HF1中细菌群落的影响大于对HF2中细菌群落的影响,HF1中COD对细菌群落的影响大于NH4^+-N和NO3^--N。  相似文献   
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