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61.
M. Grim B. Christ H. J. Jacob J. Kulich J. Pařízek 《Cellular and molecular life sciences : CMLS》1984,40(10):1142-1146
Summary Species-specific multiple forms of carboxyesterases (CE) were determined in zymograms obtained by isoelectric focusing (IEF) using homogenized wing zeugopodal tissues of chick, quail and quail-chick chimeras. The validity of the CE pattern of chimeric tissues was verified by the nuclear marker technique. Analytical IEF of CE was found to be useful for investigation of the origin of tissues in chimeras.Acknowledgment. This work was supported by grant AM21026. 相似文献
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Summary The right wing bud of 4-day-old chick embryos is suggested as a cultivation site for embryonic epithelial membranes. 相似文献
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Nanostructured semiconductors have been researched intensively for energy conversion and storage applications in recent decades. Despite of tremendous find- ings and achievements, the performance of the devices resulted from the nanomaterials in terms of energy conversion efficiency and storage capacity needs further improvement to become economically viable for subsequent commercializa- tion. Hydrogenation is a simple, efficient, and cost-effective way for tailoring the electronic and morphological properties of the nanostructured materials. This work reviews a series of hydrogenated nanostructured materials was produced by the hydrogenation of a wide range of nanomaterials. These materials with improved inherent conductivity and changed characteristic lattice structure possess much enhanced per- formance for energy conversion application, e.g., photo- electrocatalytic production of hydrogen, and energy storage applications, e.g., lithium-ion batteries and supercapacitors. The hydrogenation mechanisms as well as resultant properties responsible for the efficiency improvement are explored in details. This work provides guidance for researchers to use the hydrogenation technology to design functional materials. 相似文献
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Mikkelsen TS Wakefield MJ Aken B Amemiya CT Chang JL Duke S Garber M Gentles AJ Goodstadt L Heger A Jurka J Kamal M Mauceli E Searle SM Sharpe T Baker ML Batzer MA Benos PV Belov K Clamp M Cook A Cuff J Das R Davidow L Deakin JE Fazzari MJ Glass JL Grabherr M Greally JM Gu W Hore TA Huttley GA Kleber M Jirtle RL Koina E Lee JT Mahony S Marra MA Miller RD Nicholls RD Oda M Papenfuss AT Parra ZE Pollock DD Ray DA Schein JE Speed TP Thompson K VandeBerg JL Wade CM Walker JA Waters PD Webber C 《Nature》2007,447(7141):167-177
We report a high-quality draft of the genome sequence of the grey, short-tailed opossum (Monodelphis domestica). As the first metatherian ('marsupial') species to be sequenced, the opossum provides a unique perspective on the organization and evolution of mammalian genomes. Distinctive features of the opossum chromosomes provide support for recent theories about genome evolution and function, including a strong influence of biased gene conversion on nucleotide sequence composition, and a relationship between chromosomal characteristics and X chromosome inactivation. Comparison of opossum and eutherian genomes also reveals a sharp difference in evolutionary innovation between protein-coding and non-coding functional elements. True innovation in protein-coding genes seems to be relatively rare, with lineage-specific differences being largely due to diversification and rapid turnover in gene families involved in environmental interactions. In contrast, about 20% of eutherian conserved non-coding elements (CNEs) are recent inventions that postdate the divergence of Eutheria and Metatheria. A substantial proportion of these eutherian-specific CNEs arose from sequence inserted by transposable elements, pointing to transposons as a major creative force in the evolution of mammalian gene regulation. 相似文献
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TJ Pugh SD Weeraratne TC Archer DA Pomeranz Krummel D Auclair J Bochicchio MO Carneiro SL Carter K Cibulskis RL Erlich H Greulich MS Lawrence NJ Lennon A McKenna J Meldrim AH Ramos MG Ross C Russ E Shefler A Sivachenko B Sogoloff P Stojanov P Tamayo JP Mesirov V Amani N Teider S Sengupta JP Francois PA Northcott MD Taylor F Yu GR Crabtree AG Kautzman SB Gabriel G Getz N Jäger DT Jones P Lichter SM Pfister TM Roberts M Meyerson SL Pomeroy YJ Cho 《Nature》2012,488(7409):106-110
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T Hashimoto T Perlot A Rehman J Trichereau H Ishiguro M Paolino V Sigl T Hanada R Hanada S Lipinski B Wild SM Camargo D Singer A Richter K Kuba A Fukamizu S Schreiber H Clevers F Verrey P Rosenstiel JM Penninger 《Nature》2012,487(7408):477-481
Malnutrition affects up to one billion people in the world and is a major cause of mortality. In many cases, malnutrition is associated with diarrhoea and intestinal inflammation, further contributing to morbidity and death. The mechanisms by which unbalanced dietary nutrients affect intestinal homeostasis are largely unknown. Here we report that deficiency in murine angiotensin I converting enzyme (peptidyl-dipeptidase A) 2 (Ace2), which encodes a key regulatory enzyme of the renin-angiotensin system (RAS), results in highly increased susceptibility to intestinal inflammation induced by epithelial damage. The RAS is known to be involved in acute lung failure, cardiovascular functions and SARS infections. Mechanistically, ACE2 has a RAS-independent function, regulating intestinal amino acid homeostasis, expression of antimicrobial peptides, and the ecology of the gut microbiome. Transplantation of the altered microbiota from Ace2 mutant mice into germ-free wild-type hosts was able to transmit the increased propensity to develop severe colitis. ACE2-dependent changes in epithelial immunity and the gut microbiota can be directly regulated by the dietary amino acid tryptophan. Our results identify ACE2 as a key regulator of dietary amino acid homeostasis, innate immunity, gut microbial ecology, and transmissible susceptibility to colitis. These results provide a molecular explanation for how amino acid malnutrition can cause intestinal inflammation and diarrhoea. 相似文献
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