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Multiple cold resistance loci confer the high cold tolerance adaptation of Dongxiang wild rice (Oryza rufipogon) to its high-latitude habitat 总被引:4,自引:0,他引:4
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含par位点的重组质粒Psjm3的构建及其稳定性研究 总被引:3,自引:0,他引:3
利用自然质粒pSC101par位点的分离稳定性功能,构建了含par位点的质粒pSJM4和pSJM3,通过在同样宿主E.coli HB101中的稳定性比较研究表明,不含par位点的重组质粒pSJ3很不稳定,E.coli G3(pSJ3)在培养到第10代时已开始出现pSJ3的丢失,到培养至50代时则已全部丢失;而含par位点的重组质粒pSJM3则表现得十分稳定,E.coli G3-1(pSJM3)经70代培养,仍无明显的质粒丢失现象,其稳定率保持97%以上。通过对不含par和含par的非重组质粒pUC18和pSJM4的稳定性比较也获得同样的结果。通过对E.coliG3(pSJ3)和E.coli G3-1(pSJM3)的产酶活性比较研究表明,G3-1菌株明显高于G3菌株,说明我们构建的重组质粒pSJM3上的par位点功能不仅没有因外源基因的表达而受影响,而且有利于外源基因的表达。 相似文献
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Tomohiro Teraminami Atsushi Nakashima Mao Ominami Masanori Yamamoto Zhang Guo Sheng Ken Yoshikawa 《Landscape and Ecological Engineering》2013,9(2):249-257
Salix cheilophila Schneid. is a naturally occurring Salix species in Mu Us Sandy Land, Inner Mongolia, China. We focused on the morphological adaptability of S. cheilophila to sand dune burial. For morphological measurements, 32 S. cheilophila seedlings were removed from a community which was in the process of being buried by a shifting sand dune. Each seedling collected included the entire root system. We measured the number, length, and biomass of the adventitious roots, primary lateral roots, and taproot, and compared the morphological characteristics of the root system, including adventitious roots, for seedlings buried to various levels in the sand. The growth range of adventitious roots increased as the length of the buried portion of the main shoot increased. In addition, the total dry weight of all current-year shoots tended to increase gradually with increasing total dry weight of the adventitious roots. These results suggest that S. cheilophila tends to make use of the sedimentary sand layer that accompanies shifting sand dunes. However, there was no correlation between biomass or number of adventitious roots and the length of the buried part of the main shoot. Thus, S. cheilophila does not grow adventitious roots proportional to the buried part. These morphological characteristics of the root system, including the adventitious roots, may indicate that S. cheilophila has poor morphological adaptability to sand dune burial. 相似文献
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Li Songtao Zhao Hongling Wang Ruxing Wang Jianping Mao Xiaoxia Hao Ting Chang Xiaomin Zhao Enhong Yin Zhifeng Deng Shuhua Yang Yaqi Wang Huina 《International journal of peptide research and therapeutics》2019,25(4):1361-1367
International Journal of Peptide Research and Therapeutics - It is demonstrated that gonadotropin-releasing hormone (GnRH) analogs can directly inhibit the proliferation of reproductive tissue... 相似文献
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蹄蝠科的核型进化:比较染色体涂色、G带和C带分析(英文) 总被引:1,自引:0,他引:1
与其姐妹科(菊头蝠科)相比,蹄蝠科的细胞遗传学研究较少。迄今为止,仅少数蹄蝠科几个物种有高分辨率的G带核型报道,且有关该科核型进化的大多数结论都是基于常规Giemsa染色研究而得。该研究利用三叶小蹄蝠的染色体特异探针,通过比较染色体涂色、G和C显带,建立了5种蹄蝠的染色体同源性图谱,并探讨了它们同源染色体间的G和C带异同。结果表明:罗伯逊易位、臂内倒位以及异染色质的扩增可能是蹄蝠科物种核型进化的主要机制。通过对这5种蹄蝠物种及其外群物种之间的同源染色体片段的比较分析,作者推测蹄蝠科的祖先核型并不像先前认为的全由端着丝粒染色体组成,而应该含有中着丝粒染色体。 相似文献
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Dingqian Wu Xiaoxiao Fu Yuanyuan Zhang Qiang Li Ligang Ye Shu Han Mao Zhang 《Experimental biology and medicine (Maywood, N.J.)》2020,245(18):1683
C16 peptide and angiopoietin-1 (Ang-1) have been found to have anti-inflammatory activity in various inflammation-related diseases. However, their combined role in acute respiratory distress syndrome (ARDS) has not been investigated yet. The objective of this study was to investigate the effects of C16 peptide and Ang-1 in combination with lipopolysaccharide (LPS)-induced inflammatory insult in vitro and in vivo. Human pulmonary microvascular endothelial cells and human pulmonary alveolar epithelial cells were used as cell culture systems, and an ARDS rodent model was used for in vivo studies. Our results demonstrated that C16 and Ang-1 in combination significantly suppressed inflammatory cell transmigration by 33% in comparison with the vehicle alone, and decreased the lung tissue wet-to-dry lung weight ratio to a maximum of 1.53, compared to 3.55 in the vehicle group in ARDS rats. Moreover, C + A treatment reduced the histology injury score to 60% of the vehicle control, enhanced arterial oxygen saturation (SO2), decreased arterial carbon dioxide partial pressure (PCO2), and increased oxygen partial pressure (PO2) in ARDS rats, while also improving the survival rate from 47% (7/15) to 80% (12/15) and diminishing fibrosis, necrosis, and apoptosis in lung tissue. Furthermore, when C + A therapy was administered 4 h following LPS injection, the treatment showed significant alleviating effects on pulmonary inflammatory cell infiltration 24 h postinsult. In conclusion, our in vitro and in vivo studies show that C16 and Ang-1 exert protective effects against LPS-induced inflammatory insult. C16 and Ang-1 hold promise as a novel agent against LPS-induced ARDS. Further studies are needed to determine the potential for C16 and Ang-1 in combination in treating inflammatory lung diseases. 相似文献