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1.
DNaseⅠ超敏感位点的研究能够发现潜在的调控基因转录活化的位点,比较正常人外周血有核细胞,淋巴瘤细胞株P3HR1和人鼻咽癌低分化磷癌细胞株HOnE1和HNE2中Ha-ras-1瘤基因的DNaseⅠ超敏感位点发现,只有HONE1和HNE2细胞基因组中存在一个DNaseⅠ超敏感位点,位于第一个外显子上游0.37kb处,上述结果提示正常白细胞和P3HR1细胞中Ha-ras-1基因处于失活状态,而在鼻咽癌细胞基因组中则处于活化状态,它的活化可能与0.37kb处的DNA序列有密切的关系。 相似文献
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Parthenogenetic sporophytes were obtained from three strains of Laminaria japonica Areschoug. These sporophytes grew to maturity in the sea, producine spores that all grew into female gametophytes. These female gametophytes gave rise to another generation of parthenogenetic sporophytes during the next year, so that by the year 1990 parthenogenetic sporophytes had been cultivated for 12, 9, and 7 generations, respectively, for the three strains. When female gametophytes from parthenogenetic sporophytes were combined with normal male gametophytes, normal sporophytes that reproduced and gave rise to both female and male gametophytes were obtained. The parthenogenetic sporophytes were shorter and narrower than the normal sporophytes of the same strain. Chromosome counts on mature sporophytes showed that normal sporophytes (from fertilized eggs) were diploid (2n = approximately 40) and that the spores they produced were haploid (n = approximately 20), while nuclei from both somatic and sporangial cells in parthenogenetic sporophytes were haploid. All gametophytes were haploid. Young sporophytes derived from cultures with both female and male gametophytes were diploid, while young, sporophytes obtained from female gametophytes from parthenogenetic sporophytes had haploid, diploid, or polyploidy chromosome numbers. Polyploidy was associated with abnormal cell shapes. The presence of haploid parthenogenetic sporophytes should be use in breeding kelp strains with useful characteristics, since the sporophyte phenotype is expressed from a haploid genotype which can be more readily selected. 相似文献
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R T Mason J P Coghlan D A Denton D W Fei B A Scoggins J A Whitworth 《Prostaglandins》1984,27(4):527-534
The haemodynamic and renin responses to prostacyclin (PGI2) infusion were examined in sheep during sodium depletion and dietary sodium restriction. The haemodynamic effects of PGI2 infusion in sodium depleted and sodium restricted sheep were similar to those obtained in the sodium replete animal. The renin proportionate response to PGI2 was not altered by sodium restriction but blunted by sodium depletion, compatible with the hypothesis that endogenous PGI2 is high in Na depletion. 相似文献
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了解野放丹顶鹤的运动模式、家域和栖息地选择的时间节律特征对丹顶鹤种群保护和栖息地管理尤为重要。基于GPS-GSM跟踪数据,综合运用3S技术、动态布朗桥模型、栖息地选择指数,研究了盐城海滨湿地野放丹顶鹤在不同生活周期的活动节律、家域的面积和重叠指数,以及栖息地选择。结果表明:(1)丹顶鹤日活动节律具有明显的周期性特征。丹顶鹤活动强度:育成期>越冬期>孵化期>育雏期,孵化期和育雏期日间活动强度平稳,育成期和越冬期呈“双峰”模式。(2)丹顶鹤95%家域面积均值介于(111.18±22.15)hm2—(621.28±105.77)hm2,育成期((621.28±105.77) hm2)>育雏期((226.83±54.86) hm2)>孵化期((112.40±7.72) hm2)>越冬期((111.18±22.15) hm2);核心家域面积均值介于(0.53±0.26)—(45.78±6.66) hm2,育成... 相似文献
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Fei Tian Sijia Liu Bingzheng Zhou Yongtao Tang Yu Zhang Cunfang Zhang Kai Zhao 《DNA research》2022,29(4)
Gymnocypris przewalskii, a cyprinid fish endemic to the Qinghai-Tibetan Plateau, has evolved unique morphological, physiological and genetic characteristics to adapt to the highland environment. Herein, we assembled a high-quality G. przewalskii tetraploid genome with a size of 2.03 Gb and scaffold N50 of 44.93 Mb, which was anchored onto 46 chromosomes. The comparative analysis suggested that gene families related to highland adaptation were significantly expanded in G. przewalskii. According to the G. przewalskii genome, we evaluated the phylogenetic relationship of 13 schizothoracine fishes, and inferred that the demographic history of G. przewalskii was strongly associated with geographic and eco-environmental alterations. We noticed that G. przewalskii experienced whole-genome duplication, and genes preserved post duplication were functionally associated with adaptation to high salinity and alkalinity. In conclusion, a chromosome-scale G. przewalskii genome provides an important genomic resource for teleost fish, and will particularly promote our understanding of the molecular evolution and speciation of fish in the highland environment. 相似文献
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Yu B Zhao Y Zhao W Chen F Liu Y Zhang J Fu W Zong Z Yu A Guan Y 《Cell biochemistry and function》2003,21(2):183-188
Bovine seminal plasma contains a group of similar proteins, namely BSP-A1, BSP-A2, BSP-A3, and BSP-30-kDa (collectively called BSP proteins), and they are secreted by the seminal vesicles. In our study, we purified the BSP-A1/-A2 through affinity chromatography and found for the first time that BSP-A1/-A2 can inhibit the activity of protein kinase C (PKC) and tyrosine protein kinase (TPK). The inhibition was dose dependent. When the PKC and TPK activities are expressed as the logarithm of percentage activity taking the activity in the absence of the BSP-A1/-A2 as 100%, there is a linear relationship between the their activities and the dose of BSP-A1/-A2. 相似文献