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A proximo-distal gradient of reduced glutathione (GSH), a non enzymatic antioxidant was observed in the original tails of the lizard, H. leschenaultii. In the regenerating tails, a gradual increase in the level of GSH was noted with tail elongation. In the newly regenerated tails also the level of GSH remained higher in the proximal part than the corresponding distal parts. 相似文献
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Muthukumar Karuppasamy Manojkumar Mahapatra Samiye Yabanoglu Gulberk Ucar Barij Nayan Sinha Arijit Basu Nibha Mishra Ashoke Sharon Umasankar Kulandaivelu Venkatesan Jayaprakash 《Bioorganic & medicinal chemistry》2010,18(5):1875-1881
3,5-Diaryl pyrazolines analogs were synthesized and evaluated for their monoamine oxidase (MAO) inhibitory activity. The compounds were found reversible and selective towards MAO-A with selectivity index in the magnitude of 103–105. The docking studies were carried out to gain further structural insights of the binding mode and possible interactions with the active site of MAO-A. Interestingly, the theoretical (Ki) values obtained by molecular docking studies were in congruence with their experimental (Ki) values. 相似文献
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不同耕作措施对冬小麦-夏玉米复种连作系统土壤有机碳和水分利用效率的影响 总被引:1,自引:1,他引:1
在连续8年田间定位试验的基础上,分析了关中平原冬小麦 夏玉米复种连作系统2008—2009年连续两个生长季期间不同耕作措施(结合秸秆还田和不还田)对土壤有机碳和水分利用率的影响.结果表明: 相对于传统耕作,保护性耕作有利于土壤有机碳、水分利用效率和作物产量的提高,其中在“深松+秸秆还田”耕作模式下的增幅最高,土壤有机碳含量在0~30 cm土层增幅达到19.5%,水分利用效率和作物产量提高了16.9%和20.5%,而免耕模式则有效提高了0~10 cm土层有机碳含量.在该地区土壤和气候条件下,深松结合秸秆粉碎还田是最理想的耕作模式,最有利于土壤有机碳累积,并提高水分利用效率和作物产量. 相似文献
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Sarkar Monaj Kumar Kar Amrita Jayaraman Adithyan Shanmugam Karthi Vadivel Vellingiri Mahapatra Santanu Kar 《Molecular biology reports》2021,48(6):5327-5334
Molecular Biology Reports - Myricitrin, a naturally occurring flavonoid in Madhuca longifolia, possesses several medicinal properties. Even though our earlier work revealed its role against the... 相似文献
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Mycobacterial lipid II is composed of a complex mixture of modified muramyl and peptide moieties linked to decaprenyl phosphate 下载免费PDF全文
Mahapatra S Yagi T Belisle JT Espinosa BJ Hill PJ McNeil MR Brennan PJ Crick DC 《Journal of bacteriology》2005,187(8):2747-2757
Structural analysis of compounds identified as lipid I and II from Mycobacterium smegmatis demonstrated that the lipid moiety is decaprenyl phosphate; thus, M. smegmatis is the first bacterium reported to utilize a prenyl phosphate other than undecaprenyl phosphate as the lipid carrier involved in peptidoglycan synthesis. In addition, mass spectrometry showed that the muropeptides from lipid I are predominantly N-acetylmuramyl-L-alanine-D-glutamate-meso-diaminopimelic acid-D-alanyl-D-alanine, whereas those isolated from lipid II form an unexpectedly complex mixture in which the muramyl residue and the pentapeptide are modified singly and in combination. The muramyl residue is present as N-acetylmuramic acid, N-glycolylmuramic acid, and muramic acid. The carboxylic functions of the peptide side-chains of lipid II showed three types of modification, with the dominant one being amidation. The preferred site for amidation is the free carboxyl group of the meso-diaminopimelic acid residue. Diamidated species were also observed. The carboxylic function of the terminal D-alanine of some molecules is methylated, as are all three carboxylic acid functions of other molecules. This study represents the first structural analysis of mycobacterial lipid I and II and the first report of extensive modifications of these molecules. The observation that lipid I was unmodified strongly suggests that the lipid II intermediates of M. smegmatis are substrates for a variety of enzymes that introduce modifications to the sugar and amino acid residues prior to the synthesis of peptidoglycan. 相似文献