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61.
62.
Ruye Ma Dandan Yu Yu Peng Hongfei Yi Yingcong Wang Taofang Cheng Bingqing Shi Guang Yang Weiming Lai Xiaosong Wu Ye Lu Jumei Shi 《Acta biochimica et biophysica Sinica》2021,(6):775-783
Resveratrol,a natural compound extracted from the skins of grapes,berries,or other fruits,has been shown to have anti-tumor effects against multiple myeloma(MM)... 相似文献
63.
Ze-Hua Wang Yue-Nan Zhou Xi-Qian Ye Xiao-Tong Wu Pei Yang Min Shi Jian-Hua Huang Xue-Xin Chen 《Insect Science》2021,28(6):1567-1581
Polydnaviruses (PDVs) are obligatory symbionts of parasitoid wasps and play an important role in suppressing host immune defenses. Although PDV genes that inhibit host melanization are known in Microplitis bracovirus, the functional homologs in Cotesia bracoviruses remain unknown. Here, we find that Cotesia vestalis bracovirus (CvBV) can inhibit hemolymph melanization of its host, Plutella xylostella larvae, during the early stages of parasitization, and that overexpression of highly expressed CvBV genes reduced host phenoloxidase activity. Furthermore, CvBV-7-1 in particular reduced host phenoloxidase activity within 12 h, and the injection of anti-CvBV-7-1 antibody increased the melanization of parasitized host larvae. Further analyses showed that CvBV-7-1 and three homologs from other Cotesia bracoviruses possessed a C-terminal leucine/isoleucine-rich region and had a similar function in inhibiting melanization. Therefore, a new family of bracovirus genes was proposed and named as C -terminal L eucine/isoleucine-rich P rotein (CLP). Ectopic expression of CvBV-7-1 in Drosophila hemocytes increased susceptibility to bacterial repression of melanization and reduced the melanotic encapsulation of parasitized D. melanogaster by the parasitoid Leptopilina boulardi. The formation rate of wasp pupae and the eclosion rate of C. vestalis were affected when the function of CvBV-7-1 was blocked. Our findings suggest that CLP genes from Cotesia bracoviruses encoded proteins that contain a C-terminal leucine/isoleucine-rich region and function as melanization inhibitors during the early stage of parasitization, which is important for successful parasitization. 相似文献
64.
65.
Chengcheng Liang Xiong Xiong Rongwei Cui Yuanxiao Hong Xin Liu Guoru Zhao Lizi Ye Shuxin Qu 《仿生工程学报(英文版)》2021,18(4):927-943
The aim of this study was to reconstruct surface porous structure with hundreds of micrometers and then bio-mineralize Sr-doped Calcium Phosphate(Sr-doped CaP)o... 相似文献
66.
Fast classification and compositional analysis of cornstover fractions using Fourier transform near-infrared techniques 总被引:2,自引:0,他引:2
The objectives of this research were to determine the variation of chemical composition across botanical fractions of cornstover, and to probe the potential of Fourier transform near-infrared (FT-NIR) techniques in qualitatively classifying separated cornstover fractions and in quantitatively analyzing chemical compositions of cornstover by developing calibration models to predict chemical compositions of cornstover based on FT-NIR spectra. Large variations of cornstover chemical composition for wide calibration ranges, which is required by a reliable calibration model, were achieved by manually separating the cornstover samples into six botanical fractions, and their chemical compositions were determined by conventional wet chemical analyses, which proved that chemical composition varies significantly among different botanical fractions of cornstover. Different botanic fractions, having total saccharide content in descending order, are husk, sheath, pith, rind, leaf, and node. Based on FT-NIR spectra acquired on the biomass, classification by Soft Independent Modeling of Class Analogy (SIMCA) was employed to conduct qualitative classification of cornstover fractions, and partial least square (PLS) regression was used for quantitative chemical composition analysis. SIMCA was successfully demonstrated in classifying botanical fractions of cornstover. The developed PLS model yielded root mean square error of prediction (RMSEP %w/w) of 0.92, 1.03, 0.17, 0.27, 0.21, 1.12, and 0.57 for glucan, xylan, galactan, arabinan, mannan, lignin, and ash, respectively. The results showed the potential of FT-NIR techniques in combination with multivariate analysis to be utilized by biomass feedstock suppliers, bioethanol manufacturers, and bio-power producers in order to better manage bioenergy feedstocks and enhance bioconversion. 相似文献
67.
南海岛屿种子植物区系地理的研究 总被引:13,自引:2,他引:13
本文通过实地考察,广泛收集前人的研究资料,概述了南海岛屿地区的自然条件和植被,对南海岛屿种子植物的区系组成、特点、分布区类型、特有现象和替代现象等进行了较详细的分析,并与邻近植物区系进行了比较研究。同时,根据区内植物分布的特点和自然条件特征划分为5个植物区系小区,最后对南海岛屿地区植物区系的起源与演化进行了讨论。 相似文献
68.
锡林郭勒盟煤电基地开发生态脆弱性评价 总被引:2,自引:3,他引:2
内蒙古锡林郭勒盟国家大型煤电基地的建设,对我国华北和华东区域能源安全具有重要的作用。但随着锡盟大型煤电基地的开发,其对锡林郭勒盟这一具有重要生态屏障功能的典型草原区的生态环境造成不利影响。通过对区域生态敏感性、生态弹性及生态压力的系统研究,建立了基于生态敏感性、生态弹性及生态压力的生态脆弱性评价模型,对该区域生态脆弱性进行了评价。结果表明,锡盟地区总体生态环境质量较好,但呈现由东北向西南递减的特征。研究为锡林郭勒盟国家大型煤电基地的开发建设,区域协调发展与生态环境保护提供理论支持。 相似文献
69.
Guoqin Huang Xiuying Liu Longwang Liu Fang Ye Mingling Zhang Yanhong Shu 《Frontiers of Biology in China》2008,3(3):344-350
According to the principles and methods of ecology and system engineering, we set up an evaluation indicator system for multi-component
and multiple cropping systems, evaluated the comprehensive benefits of multi-component and multiple cropping systems using
grey relation clustering analysis and screened out the optimized model based on research done in the upland red soil in Jiangxi
Agricultural University from 1984 to 2004. The results show that the grey relation degree of “cabbage/potato/maize — sesame”
was the highest among 23 multi-component and multiple cropping systems and was clustered into the optimized system. This indicates
that “cabbage/potato/maize — sesame” can bring the best social, economic and ecological benefits, increase product yield and
farmers’ income and promote sustainable development of agricultural production. Therefore, it is suitable for promotion on
upland red soil. The grey relation degree of “canola/Chinese milk vetch/maize/mung bean/maize” was second, which is suitable
for implementation at the city outskirts. In conclusion, these two planting patterns are expected to play important roles
in the reconstruction of the planting structure and optimization of the planting patterns on upland red soil.
__________
Translated from Acta Ecologica Sinica, 2006, 26(8): 2532–2539 [译自: 生态学报] 相似文献
70.
Microbial transformation of ginsenoside Rb1 by Rhizopus stolonifer and Curvularia lunata 总被引:2,自引:0,他引:2
Of 49 microbial strains screened for their capabilities to transform ginsenoside Rb1, Rhizopus stolonifer and Curvularia lunata produced four key metabolites: 3-O-[-d-glucopyranosyl-(1,2)--d-glucopyranosyl]- 20-O-[-d-glucopyranosyl]-3,12, 20(S)-trihydroxydammar-24-ene (1), 3-O-[-d-glucopyranosyl-(1,2)--d- glucopyranosyl]-20-O-[-d-glucopyranosyl]-3,12, 20(S)-trihydroxydammar-24-ol (2), 3-O-[-d-gluco- pyranosyl-(1,2)--d-glucopyranosyl]-3, 12, 20(S)-trihydroxydammar-24-ene (3), and 3-O--d-glucopyranosyl-3, 12, 20(S)-trihydroxydammar-24-ene (4), identified by TOF-MS, 1H- and 13C-NMR spectral data. Metabolites 1, 3 and 4 were from the incubation with R. stolonifer, and 1 and 2 from the incubation with C. lunata. Compound 2 was identified as a new compound. 相似文献