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531.
Goué Nadia Montiel Grégory Levert Isabelle Gaudet Muriel Jay-Allemand Christian Label Philippe 《Trees - Structure and Function》2003,17(4):316-324
Trees - Improved wood production is a major aim for walnut forests and especially for hybrid walnut (Juglans nigra×Juglans regia). This paper presents the first report describing the structure... 相似文献
532.
Six novel 2‐(benzylcarbamoyl)phenyl derivatives were synthesized and characterized by 1H‐NMR, mass spectrometry, infrared spectra and elemental analysis. Their europium complexes were prepared and characterized by elemental analysis, EDTA titrimetric analysis, IR and UV spectra as well as molar conductivity measurements. The luminescence properties of these complexes were investigated and results show that 2‐(benzylcarbamoyl)phenyl derivatives possess high selectivity and good coordination with the europium ion. Complex Eu‐2‐(benzylcarbamoyl)phenyl‐2‐phenylacetate showed green luminescence that was emitted by the ligand of 2‐(benzylcarbamoyl)phenyl‐2‐phenylacetate, while other complexes showed the characteristic red luminescence of europium ion and also possessed high luminescence intensity. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
533.
Bao-Di Gou Yang Liu Yu-Xi Gao Kun Tang Lei Zheng Yi-Dong Zhao Tian-Lan Zhang 《Journal of structural biology》2019,205(1):41-47
The total calcium (tCa) in blood serum comprises free Ca2+ ions (fCa), protein-bound calcium (prCa), and complexed calcium by small anions (cCa). The cCa fraction, in addition to fCa, has been indicated to have some physiological activity. However, there is little evidence for the structure of its constituents. Here we report an ex vivo detection of the cCa constituents by synchrotron X-ray absorption near-edge structure spectroscopy. We collected the data directly on rat blood serum and, by making use of the reference samples, derived a spectrum that exhibits the features of cCa constituents. Among the features are those of the complexes of calcium phosphate and calcium carbonate. The detected complexes in the cCa fraction are mainly Ca(η2-HPO4)(H2O)4 and Ca(η1-HCO3)(H2O)5+, in which HPO42? and HCO3? serve as bidentate and unidentate ligands, respectively. The remained H2O molecules on the coordination sphere of Ca2+ enable these complexes to behave partially like aquated Ca2+ ions in protein-binding. Besides, as the dominant part of prCa, albumin-bound calcium (albCa) exhibits a spectrum that closely resembles that of fCa, indicating weak interactions between the protein carboxyl groups and calcium. The weak-bound cCa and albCa, along with fCa and the relevant anions, compose a local chemical system that could play a role in maintaining the calcium level in blood. 相似文献
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536.
Background
It is not clear how foreign DNA molecules insert into the host genome. Recently, we have produced transgenic mice to investigate the role of the fad2 gene in the conversion of oleic acid to linoleic acid. Here we describe an integration mechanism of fad2 transgene by homologous illegitimate random integration. 相似文献537.
538.
Sihu Dou Maocai Xu Jiazhuang Tian Bangcui Zhang Shuling Gao Yanhua Yang Baoling Wang Xiangguang Li Gaozhang Gou 《Luminescence》2023,38(8):1501-1510
To better understand the relationship between molecular structure and mechanofluorochromic characteristics, three carbazole-based N^O-chelated difluoroboron compounds ( Cz-S-BF 2 , Cz-PhNp-S-BF 2 , and Cz-BNp-S-BF 2 ) with different aryl substituents moieties were designed and synthesized. The mechanofluorochromic behaviours of Cz-S-BF 2 (luminescence from bluish-green to yellowish-green, emission from 504 to 535 nm) without aryl substitution and Cz-PhNp-S-BF 2 (luminescence from green and yellow, emission from 521 to 557 nm) with a phenyl-naphthalene group underwent reversible conversion using the grinding–fuming process. For Cz-BNp-S-BF 2 this was not apparent due to the well coplanarity of the binaphthalene moiety. Mechanofluorochromic properties were demonstrated through XRD patterns measurement. We envisage that this study will provide a practicable reference to acquire organic molecules with mechanofluorochromic characteristics. 相似文献
539.
In contrast to large-effect qualitative disease resistance, quantitative disease resistance (QDR) exhibits partial and generally durable resistance and has been extensively utilized in crop breeding. The molecular mechanisms underlying QDR remain largely unknown but considerable progress has been made in this area in recent years. In this review, we summarize the genes that have been associated with plant QDR and their biological functions. Many QDR genes belong to the canonical resistance gene categories with predicted functions in pathogen perception, signal transduction, phytohormone homeostasis, metabolite transport and biosynthesis, and epigenetic regulation. However, other “atypical” QDR genes are predicted to be involved in processes that are not commonly associated with disease resistance, such as vesicle trafficking, molecular chaperones, and others. This diversity of function for QDR genes contrasts with qualitative resistance, which is often based on the actions of nucleotide-binding leucine-rich repeat (NLR) resistance proteins. An understanding of the diversity of QDR mechanisms and of which mechanisms are effective against which classes of pathogens will enable the more effective deployment of QDR to produce more durably resistant, resilient crops. 相似文献
540.
Xi D Liu Q Guo J Yu H Yang Y He Y Mao H Gou X Deng W 《Molecular biology reports》2012,39(2):2011-2020
The gayal (Bos frontalis) is a rare semi-wild bovid species in which bovine spongiform encephalopathy (BSE) has not been reported. Polymorphisms of
the prion protein gene (PRNP) have been correlated significantly with resistance to BSE. In this study, the coding region of PRNP was cloned and characterized in samples from 125 gayal. A total of ten single nucleotide polymorphisms (SNPs), including
six silent mutations (C60T, G75A, A108T, G126A, C357T and C678T) and four mis-sense mutations (C8A, G145A, G461A and C756G),
corresponding to amino acids T3K, G49S9, N154S and I252M were identified, revealing high genetic diversity. Three novel SNPs
including C60T, G145A and C756G, which have not been reported previously in bovid species, were retrieved. There also was
one insertion–deletion (187Del24) at the N-terminal octapeptide repeat region. Alignment of nucleotide and amino acid sequences
showed a high degree of similarity with other bovid species. Using phylogenetic analyses it was revealed that gayal has a
close genetic relationship with Zebu cattle. In short, preliminary information is provided about genotypes of the PRNP in gayal. This could assist with the study of the pathogenesis of transmissible spongiform encephalopathies and cross species
transmission as well as a molecular breeding project for gayal in China. 相似文献