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61.
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Hong Yan Yue Hong Zhang Jing Chang Xin Gao Shuo Huang Long Hui Yao Xuan Yu Lin Er Jun Guo 《Analytical biochemistry》2015
A three-dimensional (3D) continuous and interconnected network graphene foam (GF) was synthesized by chemical vapor deposition using nickel foam as a template. The morphologies of the GF were observed by scanning electron microscopy. X-ray diffraction and Raman spectroscopy were used to investigate the structure of GF. The graphene with few layers and defect free was closely coated on the backbone of the 3D nickel foam. After etching nickel, the GF was transferred onto indium tin oxide (ITO) glass, which acted as an electrode to detect uric acid using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The GF/ITO electrode showed a high sensitivity for the detection of uric acid: approximately 9.44 mA mM−1 in the range of 25 nM–0.1 μM and 1.85 mA mM−1 in the range of 0.1–60 μM. The limit of detection of GF/ITO electrode for uric acid is 3 nM. The GF/ITO electrode also showed a high selectivity for the detection of uric acid in the presence of ascorbic acid. This electrode will have a wide range of potential application prospects in electrochemical detection. 相似文献
63.
Background
The epicuticular waxy layer of plant leaves enhances the extreme environmental stress tolerance. However, the relationship between waxy layer and saline tolerance was not established well. The epicuticular waxy layer of rice (Oryza sativa L.) was studied under the NaHCO3 stresses. In addition, strong saline tolerance Puccinellia tenuiflora was chosen for comparative studies.Results
Scanning electron microscope (SEM) images showed that there were significant changes in waxy morphologies of the rice epicuticular surfaces, while no remarkable changes in those of P. tenuiflora epicuticular surfaces. The NaHCO3-induced morphological changes of the rice epicuticular surfaces appeared as enlarged silica cells, swollen corns-shapes and leaked salt columns under high stress. Energy dispersive X-ray (EDX) spectroscopic profiles supported that the changes were caused by significant increment and localization of [Na+] and [Cl−] in the shoot. Atomic absorption spectra showed that [Na+]shoot/[Na+]root for P. tenuiflora maintained stable as the saline stress increased, but that for rice increased significantly.Conclusion
In rice, NaHCO3 stress induced localization and accumulation of [Na+] and [Cl−] appeared as the enlarged silica cells (MSC), the swollen corns (S-C), and the leaked columns (C), while no significant changes in P. tenuiflora. 相似文献64.
65.
《Mycological Research》2006,110(5):575-582
Gymnomyces xerophilus sp. nov., a sequestrate species in the Russulaceae, is characterized and described morphologically as a new species from Quercus-dominated woodlands in California. ITS sequences recovered from healthy, ectomycorrhizal roots of Quercus douglasii and Q. wislizeni matched those of G. xerophilus basidiomata, confirming the ectomycorrhizal status of this fungus. Phylogenetic analysis of the ITS region places G. xerophilus in a clade with both agaricoid (Russula in the section Polychromae) and sequestrate (Gymnomyces, Cystangium) relatives. We include a dichotomous key to the species of Gymnomyces associated with Quercus. 相似文献
66.
E. Yu. Zvychainaya A. A. Danilkin M. V. Kholodova T. P. Sipko A. P. Berber 《Biology Bulletin》2011,38(5):434-439
Analysis the of cytochrome b gene (1140 b.p.) polymorphism and polymorphism of 79 specimens of the control region (934 b.p.) of mtDNA of the Siberian
roe deer Capreolus pygargus from 23 regions of Russia and Kazakhstan has been carried out. The combined alignment of two fragments of mitochondrial DNA
revealed 36 haplotypes, which are distributed in three haplogroups. The net distance was 0.8, 1.3, and 1.3%. The specific
pattern of haplogroups was described for roe deer of each region (Ural, trans-Ural, Eastern Siberia, Far East, Northeastern
China). Unrelated haplogroups were found in populations of the Urals and Siberia. The variation pattern and spatial distribution
of mitochondrial lines allowed us to suggest that a haplogroup that initially belongs to C. p. tianschanicus occurs secondarily in C. p. pygargus. 相似文献
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目的:从星星草中克隆一个铁蛋白相关基因,分析其序列特征及基因表达模式。方法与结果:构建星星草RACE cDNA文库,根据GenBank中报道的铁蛋白基因EST序列设计引物,利用RACE方法克隆得到星星草铁蛋白基因PtFer的全长cDNA序列(GenBank登录号为HM125047);序列分析表明,PtFer的核苷酸序列长度为751 bp,开放读框为336 bp,编码111个氨基酸残基,预测蛋白质相对分子质量为12.8×103。其蛋白质序列具有铁蛋白的特征性保守区域,与水稻属同一进化分支,与其他禾本科植物铁蛋白的序列相似性达80%以上。Northern杂交分析表明,PtFer的表达量随Na2CO3的浓度和时间的增加而升高,并在12~24 h内持续保持较高的表达水平。结论:用分子生物学及生物信息学技术克隆并分析了星星草铁蛋白基因PtFer的全长cDNA序列及编码蛋白的结构,并初步探索了盐碱胁迫下其表达模式,为研究植物耐盐碱机理奠定了基础。 相似文献
70.
支气管哮喘(简称哮喘)是常见的慢性病,随着过敏患者的增加,小鼠过敏性哮喘模型的研究越来越重要。本文通过对近年来国内外小鼠过敏性哮喘的实验研究文献进行总结,从实验小鼠的选择、制备模型的方法及模型的评价指标等方面进行综合分析,为进一步开展哮喘研究提供帮助。 相似文献