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排序方式： 共有507条查询结果，搜索用时 15 毫秒
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Wakayama T Tabar V Rodriguez I Perry AC Studer L Mombaerts P 《Science (New York, N.Y.)》2001,292(5517):740-743
Embryonic stem (ES) cells are fully pluripotent in that they can differentiate into all cell types, including gametes. We have derived 35 ES cell lines via nuclear transfer (ntES cell lines) from adult mouse somatic cells of inbred, hybrid, and mutant strains. ntES cells contributed to an extensive variety of cell types, including dopaminergic and serotonergic neurons in vitro and germ cells in vivo. Cloning by transfer of ntES cell nuclei could result in normal development of fertile adults. These studies demonstrate the full pluripotency of ntES cells. 相似文献
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Oxygen-18-oxygen-16 fractionation of coexisting quartz and magnetite from the Biwabik iron formation varies as a function of distance of the sample from an intrusive contact. This isotope fractionation is related to observed mineralogic variations and compared with a theoretical heat-flow model. 相似文献
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Barnes JW Brown RH Turtle EP McEwen AS Lorenz RD Janssen M Schaller EL Brown ME Buratti BJ Sotin C Griffith C Clark R Perry J Fussner S Barbara J West R Elachi C Bouchez AH Roe HG Baines KH Bellucci G Bibring JP Capaccioni F Cerroni P Combes M Coradini A Cruikshank DP Drossart P Formisano V Jaumann R Langevin Y Matson DL McCord TB Nicholson PD Sicardy B 《Science (New York, N.Y.)》2005,310(5745):92-95
Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80 degrees W and 20 degrees S. This area is bright in reflected light at all observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Science Subsystem. We discuss various hypotheses about the source of the spot, reaching the conclusion that the spot is probably due to variation in surface composition, perhaps associated with recent geophysical phenomena. 相似文献
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Walter S. De Jong Donald E. Halseth Bill B. Brodie Keith L. Perry Joseph B. Sieczka Barbara J. Christ Gregory A. Porter Ken M. Paddock Michael W. Peck Robert L. Plaisted 《American Journal of Potato Research》2006,83(2):189-193
‘Marcy’ is a white-skinned, white-fleshed potato cultivar notable for its high yield, good chip color, and resistance to common scab and race Ro1 of the golden cyst nematode. It was selected from a cross made at Cornell University in 1990 between ‘Atlantic’ and Q155-3. Full-season marketable yields of Marcy have averaged 15% to 20% greater than Atlantic in 83 trials across New York, Maine, and Pennsylvania. Specific gravity of Marcy has averaged 0.008 less than Atlantic. Chip color out of 7 C storage in New York has been similar to ‘Pike’, but not as light as ‘Snowden’. Marcy tubers have an attractive oval shape, shallow eyes, and highly textured skin. Marcy was jointly released by the New York and Pennsylvania Agricultural Experiment Stations in 2002. 相似文献