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排序方式: 共有9226条查询结果,搜索用时 15 毫秒
71.
Qian W Sass O Meng J Li M Frauen M Jung C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(1):27-34
Chinese semi-winter rapeseed is genetically diverse from Canadian and European spring rapeseed. This study was conducted to
evaluate the potential of semi-winter rapeseed for spring rapeseed hybrid breeding, to assess the genetic effects involved,
and to estimate the correlation of parental genetic distance (GD) with hybrid performance, heterosis, general combining ability
(GCA) and specific combining ability (SCA) in crosses between spring and semi-winter rapeseed lines. Four spring male sterile
lines from Germany and Canada as testers were crossed with 13 Chinese semi-winter rapeseed lines to develop 52 hybrids, which
were evaluated together with their parents and commercial hybrids for seed yield and oil content in three sets of field trials
with 8 environments in Canada and Europe. The Chinese parental lines were not adapted to local environmental conditions as
demonstrated by poor seed yields per se. However, the hybrids between the Chinese parents and the adapted spring rapeseed
lines exhibited high heterosis for seed yield. The average mid-parent heterosis was 15% and ca. 50% of the hybrids were superior
to the respective hybrid control across three sets of field trials. Additive gene effects mainly contributed to hybrid performance
since the mean squares of GCA were higher as compared to SCA. The correlation between parental GD and hybrid performance and
heterosis was found to be low whereas the correlation between GCA(f + m) and hybrid performance was high and significant in each set of field trials, with an average of r = 0.87 for seed yield and r = 0.89 for oil content, indicating that hybrid performance can be predicted by GCA(f + m). These results demonstrate that Chinese semi-winter rapeseed germplasm has a great potential to increase seed yield in spring
rapeseed hybrid breeding programs in Canada and Europe. 相似文献
72.
根据已知的其他物种PNAE酶cDNA序列设计引物,采用RT-PCR技术从云南萝芙木叶片中扩增获得pnae基因部分cDNA序列即PNAE酶基因中间大片段,再用RACE技术获得其两端序列。序列拼接得到完整的1 004 bp的PNAE酶基因,根据获得的序列,分析得到795 bp的开放阅读框,编码264个氨基酸。序列分析显示,云南萝芙木中PNAE酶氨基酸序列与蛇根木中的该酶氨基酸序列同源性高达90%,但和其他植物物种中的PNAE酶氨基酸序列,以及其他物种间的PNAE酶氨基酸序列同源性都不高,在40%-60%之间,表明不同物种中PNAE酶氨基酸序列不具有全序列的高度同源性。进一步序列分析发现,在各植物的PNAE酶氨基酸序列中都存在两个高度保守的氨基酸区域,表明不同物种中PNAE酶存在共同的高度保守区段。 相似文献
73.
Dragon's blood may have radioprotective effects in radiation-induced rat brain injury 总被引:2,自引:0,他引:2
74.
Yuting Wen Meng Cheng Lang Qin Wenming Xu 《Journal of cellular and molecular medicine》2022,26(10):2947
Early spontaneous abortion (ESA) is one of the most common complications during pregnancy and the inflammation condition in uterine environment such as long‐term exposure to high TNFα plays an essential role in the aetiology. Ferritin heavy chain (FTH1) is considered to be closely associated with inflammation and very important in normal pregnancy, yet the underlying mechanism of how TNFα induced abortion and its relationship with FTH1 remain elusive. In this study, we found that TNFα and FTH1 were positively expressed in decidual stromal cells and increased significantly in the ESA group compared with the normal pregnancy group (NP group). Besides, TNFα expression was positively correlated with FTH1 expression. Furthermore, in vitro cell model demonstrated that high TNFα could induce the abnormal signals of TNFR/NF‐κB/FTH1 and activate apoptosis both in human endometrium stromal cells (hESCs) and in local decidual tissues. Taken together, the present findings suggest that the excessive apoptosis in response to TNFα‐induced upregulation of FTH1 may be responsible for the occurrence of ESA, and thus provide a possible therapeutic target for the treatment of ESA. 相似文献
75.
Soomin Lee Zheng Li Dehua Meng Qinming Fei Libo Jiang Tengfei Fu Ze Wang Shuhao Liu Jian Zhang 《Acta biochimica et biophysica Sinica》2021,(11):1516-1526
Vascularization is an important early indicator of osteogenesis involving biomaterials.Bone repair and new bone formation are associated with extensive neovascu... 相似文献
76.
77.
Using two chloroplast DNA intergenic spacers, a phylogeographical study of Lagochilus ilicifolius with 168 individuals from 14 populations was performed to assess geographical patterns and genetic variation in relation to past climate change. Population structure and history were inferred by nested clade analysis, neutrality tests, divergence time estimates, and mismatch distribution analysis. Twelve haplotypes were identified. Genetic differentiation among populations within groups was also elevated (FSC = 0.772), suggesting restricted gene flow among populations within groups. Divergence time was at approximately 0.71 Ma, consistent with aridification and desert expansion during the middle Pleistocene. The Helan Mountains contained a large proportion of the haplotypes, which implies that the region may be the center of diversification for the species, whereas the Loess Plateau as a dispersal corridor for postglacial re-colonization northward. Climatic oscillation, aridification, and desert expansion within these regions have molded current distribution and biodiversity of L. ilicifolius. 相似文献
78.
Chick embryos grown in ex ovo culture by the modified Cornish pasty method reported in Nagai, Lin and Sheng in this issue. 相似文献
79.
从一株特殊生境荒漠药用植物沙蓬的内生真菌Rhinocladiella similis中分离得到4个苯甲酸大环内酯化合物,包括2个新化合物rhinoclactones E(2)和F(1)、2个已知化合物8,9-dihyrogreensporone D(3)和8,9-dihydrogreensporone A(4)。基于高分辨质谱与核磁共振谱数据以及相关文献比对,确定了新化合物与已知化合物的结构。化合物1和2是一对立体异构体,在大环内酯环中并有一个呋喃环,这种环系统在自然界比较稀少。化合物1-4对3株肿瘤细胞株和植物病原真菌没有抑制活性。本结果进一步丰富了该真菌的化学成分研究,暗示特殊生境荒漠植物内生真菌具有产生结构新颖的次级代谢产物的潜力,是发现新活性天然产物的一个新的重要宝库;此外,根据化合物的结构特征与生物活性结果,本文还探讨了这些化合物潜在的生态学功能。 相似文献
80.