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131.
水体氮素污染日益严重,如何经济、高效地去除水体氮素已成为研究热点。近年来,研究人员已从不同环境中分离到许多同时具有异养硝化和好氧反硝化功能的菌株,此类菌生长迅速,可在好氧条件下同时实现硝化和反硝化的过程,并可用于脱除有机污染物,是一类应用潜力巨大的脱氮菌。目前,异养硝化-好氧反硝化菌的脱氮途径和机制主要是通过测定氮循环中间产物或终产物、测定相关酶活性、注释部分氮循环相关基因及参考自养硝化菌和缺氧反硝化菌的氮循环途径等进行研究,其完整的氮素转化途径和氮代谢机制还需要进一步明确。总结了目前异养硝化-好养反硝化菌的脱氮相关酶系及其编码基因的研究进展,以期为异养硝化-好氧反硝化菌的理论研究及其在污水脱氮处理上的应用提供参考。 相似文献
132.
Liu Tengfei Sun Liang Meng Qiucheng Yu Jianghui Weng Lushui Li Jinjiang Deng Lihua Zhu Qihong Gu Xingyou Chen Caiyan Teng Sheng Xiao Guoying 《Plant and Soil》2021,463(1-2):39-53
Plant and Soil - Rice accumulates higher levels of cadmium (Cd) in grain than other cereals, and hybrid rice varieties cover around half of the total rice area in China. Therefore, understanding... 相似文献
133.
Triple-negative breast cancer (TNBC) is the most malignant and fatal subtype of breast cancer, which has characterized by negativity expression of ER, PR, and HER2. Metastasis is the main factor affecting the prognosis of TNBC, and the process of metastasis is related to abnormal activation of epithelial–mesenchymal transition (EMT). Recent studies have shown that long non-coding RNA (LncRNA) plays an important role in regulating the metastasis and invasion of TNBC. Therefore, based on the metastasis-related EMT signaling pathway, great efforts have confirmed that LncRNA is involved in the molecular mechanism of TNBC metastasis, which will provide new strategies to improve the treatment and prognosis of TNBC. In this review, we summarized many signal pathways related to EMT involved in the transfer process. The advances from the most recent studies of lncRNAs in the EMT-related signal pathways of TNBC metastasis. We also discussed the clinical research, application, and challenges of LncRNA in TNBC. 相似文献
134.
Yongfeng Li Xinmiao Rui Daobao Chen Haojun Xuan Hongjian Yang Xuli Meng 《Bioscience reports》2021,41(6)
Background: Long non-coding RNA associated with poor prognosis of hepatocellular carcinoma (AWPPH) is dysregulated in a variety of human cancers. However, the prognostic value of AWPPH in various cancers remains unclear.Methods: Comprehensive literature search was performed in PubMed, Web of Science, CNKI and Wangfang databases, and eligible studies were obtained according to the inclusion and exclusion criteria. The pooled hazard ratios (HRs) and odds ratios (ORs) were applied to assess the clinical value of AWPPH expression for overall survival (OS) and clinicopathological features.Results: A total of 19 articles including 1699 cancer patients were included in the study. The pooled results demonstrated that evaluated AWPPH expression was positively related to a poorer overall survival of patients with cancers (HR = 1.79, 95%CI: 1.44–2.14, P<0.001). Subgroup analysis revealed that tumor type and sample size affect the predictive value of AWPPH on OS, whereas cut-off value and HR estimation method have no impact on it. In addition, the pooled data also showed that AWPPH was positively linked to advanced TNM stage (OR = 2.50, 95%CI: 1.94–3.22, P<0.001), bigger tumor size (OR = 2.64, 95%CI: 1.47–4.73, P=0.001), macro-vascular invasion (OR = 2.08, 95%CI: 1.04–4.16, P=0.04) and lymph node metastasis (OR = 2.68, 95%CI: 1.82–3.96, P<0.001). Moreover, the results of the trim and fill analysis confirmed the reliability of our finding.Conclusions: Up-regulation of AWPPH was associated with advanced TNM stage, bigger tumor size, worse lymph node metastasis, macro-vascular invasion and shorter overall survival, suggesting that AWPPH may serve as a biomarker for prognosis and clinicopathological characteristics in human cancers among the Chinese population. 相似文献
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136.
Meng Xue Mu Fangfang Zhang Zeyu Wu Xinru Gao Tiantian Zhao Fenglan Xue Jianping Duan Yongbo Zhang Haijun 《Plant Cell, Tissue and Organ Culture》2021,146(3):473-482
Plant Cell, Tissue and Organ Culture (PCTOC) - Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. is an important medicinal plant rich in bioactive compounds. In vitro tissue culture... 相似文献
137.
【背景】化学防治污染日益严重,作物抗性、农药残留、病害再生现象越来越普遍,因此筛选新型生防菌株及研究其抗菌物质已成为热点。【目的】筛选出一株对禾旋孢腔菌等植物病原菌具有生防功能的贝莱斯芽孢杆菌,挖掘其调控合成细菌素、抗菌肽(RiPPs)的基因簇。【方法】通过分离筛选、对峙培养等方法筛选出菌株,通过全细胞脂肪酸和Biolog分析法以及分子生物学方法进行菌株鉴定。利用Illumina NovaSeq 6000平台进行全基因组序列测定,通过BAGEL4挖掘潜在的细菌素、RiPPs基因簇及潜在的作用机制。【结果】菌株RJW-5-5对禾旋孢腔菌的抑制效果最好,抑制率可达78.4%,对疫霉菌、菊池链格孢等病原菌均有较好的抑制作用,利用NCBI网站的BLAST功能对所测的16S rRNA基因和rpoB基因序列进行同源性分析,鉴定菌株RJW-5-5为贝莱斯芽孢杆菌(Bacillus velezensis)。BAGEL4分析菌株RJW-5-5全基因组序列含有合成Lasso_peptide、Cerecidin、Sactipeptides以及Propionicin_SM1的基因簇,其中Propionicin_SM1为首次在芽孢杆菌属中发现,能够合成双功能蛋白TrpGD、二硫还原酶、2-氧戊二酸脱氢酶E1组分等。【结论】菌株RJW-5-5能够抑制多种农作物病害,具有多种羊毛硫抗生素、套索肽、细菌素等抗菌肽基因簇,具有广阔的发展前景及应用潜力。 相似文献
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139.
Chai Qian Meng Ziang Lu Dexue Zhang Ziying Liu Meili Wu Weihua 《Molecular and cellular biochemistry》2021,476(6):2479-2489
Molecular and Cellular Biochemistry - Cardiomyocyte death is an important pathogenic process in cardiac complications of diabetes. Diabetic patients often suffer glycemic variability. Pyroptosis is... 相似文献