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91.
董赫男 《内蒙古民族大学学报(自然科学版)》2013,(5)
通过观察大鼠肱三头肌细胞膜自由基代谢的变化情况,研究力竭离心运动状态下自由基损伤细胞膜的可能机制,探求力竭性运动所产生的自由基对机体产生的影响,以期为训练方法和运动能力恢复手段提供理论和实验依据。研究发现,力竭离心运动后即刻自由基对细胞膜的损伤显著升高,24小时达到损伤高峰。 相似文献
92.
K. Saki Raheem Nigel P. Botting Gary WilliamsonDenis Barron 《Tetrahedron letters》2011,52(52):7175-7177
We report the first total synthesis of 3,5-O-dicaffeoylquinic acid and its derivatives, 3,5-O-diferuloylquinic acid and 3,5-(3,4-dimethoxycinnamyl)quinic acid, in a nine-step sequence. The key step involves Knoevenagel condensations between vanillin, 3,4-dimethoxybenzaldehyde or 4-hydroxy-3-methoxybenzaldehyde and the dimalonate ester of quinic acid. 相似文献
93.
Hongwei Kong Mei Wang Koen Venema Annet Maathuis Rob van der Heijden Jan van der Greef Guowang Xu Thomas Hankemeier 《Journal of chromatography. A》2009,1216(11):2195-2203
A high-performance liquid chromatography–high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC–FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by high-resolution tandem mass spectrometry. Degradation and bioconversion routes of the different ginsenosides at acidic (gastric) conditions and in the presence of intestinal microbiota were elaborated. Besides hydrolysis (deglycosylation) also hydration reactions occurred at acidic conditions. The results illustrate the value of metabolite profiling by HPLC–FTICR-MS for understanding of the mechanisms in bioavailability of herbal drugs and their metabolites. 相似文献
94.
François‐Ludovic Sauvage Nicolas Picard Franck Saint‐Marcoux Jean‐Michel Gaulier Gérard Lachâtre Pierre Marquet 《Journal of separation science》2009,32(18):3074-3083
LC coupled to single (LC–MS) and tandem (LC–MS/MS) mass spectrometry is recognized as the most powerful analytical tools for metabolic studies in drug discovery. In this article, we describe five cases illustrating the utility of screening xenobiotic metabolites in routine analysis of forensic samples using LC–MS/MS. Analyses were performed using a previously published LC–MS/MS general unknown screening (GUS) procedure developed using a hybrid linear IT–tandem mass spectrometer. In each of the cases presented, the presence of metabolites of xenobiotics was suspected after analyzing urine samples. In two cases, the parent drug was also detected and the metabolites were merely useful to confirm drug intake, but in three other cases, metabolite detection was of actual forensic interest. The presented results indicate that: (i) the GUS procedure developed is useful to detect a large variety of drug metabolites, which would have been hardly detected using targeted methods in the context of clinical or forensic toxicology; (ii) metabolite structure can generally be inferred from their “enhanced” product ion scan spectra; and (iii) structure confirmation can be achieved through in vitro metabolic experiments or through the analysis of urine samples from individuals taking the parent drug. 相似文献
95.
Summary Computer simulation of ecdysone metabolism in insects has been done by the a software called HPLC-Metabolexpert®, that served to generate the metabolic pathways of ecdysone in a retrospective manner. Some of the generated metabolites have already been detected, others are to be confirmed. Lists of the applied metabolic transformations, the predicted metabolites and their HPLC elution times are also given. 相似文献
96.
Gerhard Spiteller 《Angewandte Chemie (International ed. in English)》1985,24(6):451-465
Powerful separation methods developed during the past few decades, in particular glass capillary gas chromatography (GC) and high performance liquid chromatography (HPLC), can be combined with sensitive methods of detection such as mass spectrometry (MS) to provide new insights into metabolic processes. Research in a field that was long thought to be exhausted has thus been revitalized. New perspective have been opened up for studying the metabolism of foods, spices and flavorings, drugs, and compounds produced in the body as well as for establishing the way in which the organism rids itself of harmful substances or how and when these compounds can interfere with the metabolic processes occurring in the body. 相似文献
97.
Greatness of clear wine comes from wooden ploughs. As an indispensable part of Chinese food culture, wine has gone through thousands of years with us. This essay will make an introduction of aspects of ethanol's nature, origin, metabolism by means of personification and in form of how Alcohol pursues his own memories, aiming at making readers feel the taste of chemistry with the popularization of science integrating science and fun. 相似文献
98.
苏国兴 《苏州大学学报(医学版)》1998,14(1):85-90
受盐分胁迫,桑树叶片活性氧清除系统SOD、,CAT,POX及GSH的活性或含量水平逐渐下降,但仍维持较高的水平,并与低水平的细胞膜相对透性,膜脂过氧化作用相对应。 相似文献
99.
100.
G. M. Rodchenkov V. P. Uralets V. A. Semenov P. A. Leclercq 《Journal of separation science》1988,11(3):283-288
Adult male volunteers were administered orally 10 mg of the espective drug. Urine samples were investigated by micro-column liquid chromatography and capillary gas chromatography combined with on-line mass spectrometry. The former technique was found to be usable for the detection of these drugs. The latter method appeared to be superior in terms of sensitivity and for metabolism studies. The major excretion products of dexamethasone were identified as isomeric 6-hydroxy metabolites. Dexamethasone as such and its 20-hydroxy metabolite were found in minor quantities. Unlike dexamethasone, triamcinolone is excreted largely unchanged from the human body. Two metabolites were identified as 11-keto and 4,5-dihydrotriamcinolone. With the gas chromatography methods developed, abuse of these drugs can be detected up to 24 h after administration of a 5 mg single dose. 相似文献