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51.
In China, three institutes for botanical research were established in the 1920s. They were the Department of Botany, Biological Laboratory of the Science Society of China (1922, Nanjing), the Fan Memorial Institute of Biology (1928, Beiping), and the Institute of Botany, Beiping Academy of Sciences (1929, Beiping). 相似文献
52.
种间的遗传差异是物种分类和确定保护管理单元的基础,本研究利用DNA条形码技术对未知样本进行鉴定,通过NCBI进行BLAST得到结果是:与绿孔雀的同源性为96%。近一步通过对蓝孔雀(Pavo cristatus)和绿孔雀(Pavo muticus)线粒体细胞色素C氧化酶Ⅰ(cytochrome coxidaseⅠ,COⅠ)基因及线粒体基因组的比较分析,结果表明两物种间的COⅠ基因在碱基组成、核苷酸多样性等各项指标上均具有明显差异。遗传距离分析结果表明蓝孔雀与绿孔雀种内遗传距离为分别0和0.012,种间遗传距离为0.045,表明种间仍具有明显的遗传差异。通过对两物种线粒体基因组各基因的比较分析,发现ND1基因变异位点所占比例相对较高,考虑作为绿孔雀和蓝孔雀种群遗传学研究的最优分子标记。本研究将为分析孔雀类群间的系统发育及制定绿孔雀的保护措施提供了更多科学依据。 相似文献
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Lihua Zhang Fenghui Yuan Junhong Bai Hongtao Duan Xueying Gu Longyu Hou Yao Huang Mingan Yang Jin‐Sheng He Zhenhua Zhang Lijun Yu Changchun Song David A. Lipson Donatella Zona Walter Oechel Ivan A. Janssens Xiaofeng Xu 《Ecology letters》2020,23(5):821-830
Grassland ecosystems account for more than 10% of the global CH4 sink in soils. A 4‐year field experiment found that addition of P alone did not affect CH4 uptake and experimental addition of N alone significantly suppressed CH4 uptake, whereas concurrent N and P additions suppressed CH4 uptake to a lesser degree. A meta‐analysis including 382 data points in global grasslands corroborated these findings. Global extrapolation with an empirical modelling approach estimated that contemporary N addition suppresses CH4 sink in global grassland by 11.4% and concurrent N and P deposition alleviates this suppression to 5.8%. The P alleviation of N‐suppressed CH4 sink is primarily attributed to substrate competition, defined as the competition between ammonium and CH4 for the methane mono‐oxygenase enzyme. The N and P impacts on CH4 uptake indicate that projected increases in N and P depositions might substantially affect CH4 uptake and alter the global CH4 cycle. 相似文献
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Ming‐Yuan Du Jia‐Xi Duan Chen‐Yu Zhang Hui‐Hui Yang Xin‐Xin Guan Wen‐Jing Zhong Yan‐Zhe Liu Zi‐Ming Li Yu‐Rui Cheng Yong Zhou Cha‐Xiang Guan 《Cell biology international》2020,44(1):98-107
Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model. 相似文献
55.
Cong Tong Kai Qu Guorong Wang Ruiting Liu Baojun Duan Xiaoqiang Wang Chang Liu 《Cell biology international》2020,44(10):2075-2085
DNA‐binding protein A (dbpA) is reported to be upregulated in many cancers and associated with tumor progress. The present study aimed to investigate the role of dbpA in 5‐fluorouracil (5‐FU)‐resistant and oxaliplatin (L‐OHP)‐resistant colorectal cancer (CRC) cells. We found that 5‐FU and L‐OPH treatment promoted the expression of dbpA. Enhanced dbpA promoted the drug resistance of SW620 cells to 5‐FU and L‐OHP. DbpA knockdown inhibited cell proliferation, induced cell apoptosis, and cell cycle arrested in SW620/5‐FU and SW620/L‐OHP cells. Besides, dbpA short hairpin RNA (shRNA) enhanced the cytotoxicity of 5‐FU and L‐OHP to SW620/5‐FU and SW620/L‐OHP cells. Meanwhile, dbpA shRNA inhibited the activation of the Wnt/β‐catenin pathway that induced by 5‐FU stimulation in SW620/5‐FU cells. Activation of the Wnt/β‐catenin pathway or overexpression of checkpoint kinase 1 (Chk1) abrogated the promoting effect of dbpA downregulation on 5‐FU sensitivity of CRC cells. Importantly, downregulation of dbpA suppressed tumor growth and promoted CRC cells sensitivity to 5‐FU in vivo. Our study indicated that the knockdown of dbpA enhanced the sensitivity of CRC cells to 5‐FU via Wnt/β‐catenin/Chk1 pathway, and DbpA may be a potential therapeutic target to sensitize drug resistance CRC to 5‐FU and L‐OHP. 相似文献
56.
Jianping Duan Ying Li Jie Du Erzhen Duan Yuyu Lei Shimei Liang Xian Zhang Xin Zhao Yunchao Kan Lunguang Yao Xinfeng Yang Xingtan Zhang Xiangwei Wu 《Molecular ecology resources》2020,20(5):1372-1383
Antheraea pernyi is a semi‐domesticated lepidopteran insect species valuable to the silk industry, human health, and ecological tourism. Owing to its economic influence and developmental properties, it serves as an ideal model for investigating divergence of the Bombycoidea super family. However, studies on the karyotype evolution and functional genomics of A. pernyi are limited by scarce genomic resource. Here, we applied PacBio sequencing and chromosome structure capture technique to assemble the first high‐quality A. pernyi genome from a single male individual. The genome is 720.67 Mb long with 49 chromosomes and a 13.77‐Mb scaffold N50. Approximately 441.75 Mb, accounting for 60.74% of the genome, was identified as repeats. The genome comprises 21,431 protein‐coding genes, 85.22% of which were functionally annotated. Comparative genomics analysis suggested that A. pernyi diverged from its common ancestor with A. yamamai ~30.3 million years ago, and that chromosome fission contributed to the increased chromosome number. The genome assembled in this work will not only facilitate future research on A. pernyi and related species but also help to progress comparative genomics analyses in Lepidoptera. 相似文献
57.
Zhang Hongling Ran Chao Teame Tsegay Ding Qianwen Hoseinifar Seyed Hossein Xie Mingxu Zhang Zhen Yang Yalin Olsen Rolf Erik Gatlin Delbert M. Ringø Einar Duan Ming Zhou Zhigang 《Reviews in Fish Biology and Fisheries》2020,30(4):569-586
Reviews in Fish Biology and Fisheries - The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a... 相似文献
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2-O-α-D-甘油葡糖苷是一种在食品、化妆品、保健品及医药领域有着重大应用前景的高附加值产品,但国内仍未实现2-O-α-D-甘油葡糖苷的工业化生产,且鲜有关于2-O-α-D-甘油葡糖苷合成的相关报道。文中旨在开发一种利用食品安全级重组枯草芽孢杆菌全细胞催化合成2-O-α-D-甘油葡糖苷的方法,通过构建一株异源表达肠膜明串珠菌蔗糖磷酸化酶 (Sucrose phosphorylase,SPase) 的重组枯草芽孢杆菌Bacillus subtilis 168/pMA5-gtfA,并将其用作全细胞催化剂合成2-O-α-D-甘油葡糖苷,通过优化培养温度、时间及全细胞转化条件,提高其转化合成2-O-α-D-甘油葡糖苷的产量。结果表明,重组枯草芽孢杆菌B. subtilis 168/pMA5-gtfA在30 ℃下培养20 h,菌体裂解物酶活力最大达1.43 U/mL,并且在1 mol/L蔗糖、2.5 mol/L甘油、pH 7.0、菌体OD600为40、30 ℃下全细胞转化反应48 h,共生成2-O-α-D-甘油葡糖苷189.3 g/L,平均转化速率为15.6 mmol/(L·h),蔗糖转化率约为75.1%,是目前报道的利用重组枯草芽孢杆菌催化合成2-O-α-D-甘油葡糖苷的最高产量,这为2-O-α-D-甘油葡糖苷的工业化生产及应用奠定了理论和实验基础。 相似文献