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641.
礼赞穿越生命之河
我从青春年少时就在歌吟情有独钟的倒淌河,古稀暮秋时依然如故,让礼赞穿越生命之河,去迎接希望的春天…… 相似文献
642.
Dawei Cai Zhuowei Tang Huixin Yu Lu Han Xiaoyan Ren Xingbo Zhao Hong Zhu Hui Zhou 《Journal of archaeological science》2011,38(4):896-902
China has a long history of sheep husbandry, and has several indigenous sheep breeds. However, the exact geographic origin of Chinese domestic sheep remains unclear. To provide valuable genetic information for origin of Chinese domestic sheep, we performed an ancient DNA study on 22 sheep excavated from four Bronze Age archaeological sites in Northern China. Two lineages (A and B) were observed in ancient Chinese sheep, of which lineage A was predominant reaching a frequency of 95.5%. Furthermore, phylogenetic network showed that the most frequent haplotype in ancient sheep was the founder of lineage A. These results suggest that Lineage A may hold the key to understanding the origin of Chinese domestic sheep. Sequence sharing and principal component analysis showed that the ancient Chinese sheep had a close affinity to modern Chinese sheep. However, there was no significant breed structure among three modern Chinese sheep groups, making it difficult to determine their relationship to ancient Chinese sheep. Lastly, our results imply that ancient DNA analysis could provide a new way to investigate prehistoric East-West contact. 相似文献