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代谢组学是定量研究生物体内源性代谢物整体及其变化规律的科学,是系统生物学的一个重要组成部分. 通过代谢组分析,可以较为全面地认识给定生物系统受内因或外因的影响后其生物化学过程变化的规律. 目前,代谢组分析检测技术主要包括核磁共振波谱技术及色谱-质谱联用技术. 代谢组数据分析和挖掘技术主要包括非监督与监督的多变量分析模式识别方法. 目前已被广泛应用于病理生理、基因功能、药物毒理和环境毒理等领域. 该文简要综述了代谢组NMR分析中的实验设计、NMR谱的获取、模式识别技术和代谢组学在药物毒理评价中的应用. 相似文献
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In this paper, we establish a Liouville-type theorem for a system of higher-order parabolic inequalities by using the method of test functions and an integral estimate. As an application, we observe the Fujita blow-up phenomena for the corresponding parabolic system, which in particular fills up the gap in the recent result of Pang et. al. (Existence and nonexistence of global solutions for a higher-order semilinear parabolic system, Indiana Univ. Math. J., 55(2006), 1113-1134). Moreover, the importance of this observation is that we do not impose any regularity assumption on the initial data. 相似文献
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Isokinetic relationships of the series of electrophilic substitution reactions of o-substi-tuted phenylmercurials are studied, and the results show, for the first time, that isokinetic correlation analysis can reveal the dominant factor in the system of the reactions. The analysis of SE2 of o-substituted phenylmercuric chlorides indicates that the steric effect of o-substituents is the predominant factor when I2 is used as electrophilic agent, however, the electronic effect of o-substituents would become the predominant factor when HCI is used as the electrophilic agent. In SE1 of o-substituted phenylmercuric chlorides, the results of the analysis display that the predominant factor is the field effects of o-substituents. The determination of predominant factors in those reactions would provide further scientific basis for those reaction mechanisms. 相似文献
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绒癌是一种发生于育龄妇女的恶性滋养细胞肿瘤.经甲氨蝶呤、5-氟尿嘧啶等单药或多药联合化疗后,其治愈率通常高达90%.然而耐药仍是绒癌治疗失败的主要原因.目前绒癌耐药的机制尚不明确,前人多从蛋白和转录水平阐述,鲜有涉及代谢物层次的研究.本文采用基于核磁共振(NMR)的代谢组学方法,研究了甲氨蝶呤耐药株JEG3R与敏感株JEG3绒癌细胞及其培养基在代谢物水平上的差异.结果发现JEG3R耐药极可能与糖代谢异常相关,主要表现为耐药株细胞中山梨糖醇的累积,提示醛糖还原酶可能在耐药过程中起重要作用;其次,耐药株细胞中乳酸积累、丙氨酸流入三羧酸循环途径增强;此外,耐药株细胞相比敏感株细胞中氨基酸、核苷酸及磷酸胆碱等必需营养物质的显著性改变,且其变化与绒癌增殖速率正相关.本研究为绒癌的耐药机制研究补充了代谢层次的数据,为后续从分子生物学水平上揭示耐药机制提供了新思路. 相似文献
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随着人们对宿主肠道菌群的日益关注,关于胆汁酸与肠道菌群之间复杂关系的研究也越来越多.因肠道组织结构的复杂性和肠道菌群分布差异性,不同肠段胆汁酸的分布、表达及其生物学功能仍有待进一步研究.本文采用基于超高效液相色谱-三重四极杆-质谱联用(UPLC-QqQ-MS)的靶向代谢组分析结合基于核磁共振(NMR)波谱的非靶向代谢组分析方法,通过比较不同性别C57BL/6小鼠肠道各区段胆汁酸及粪样代谢组的变化水平,发现雌、雄小鼠不同肠段中胆汁酸的分布各不相同.另外,肠道下段各胆汁酸的性别差异性更为明显,以盲肠的性别差异性最为显著,这可能与盲肠的菌群微生态更为丰富有关.该研究为不同性别模型小鼠胆汁酸的代谢表型及其与肠道菌群的相互作用提供了基础研究数据. 相似文献
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