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71.
RNA-binding protein QKI, a member of the Signal Transduction and Activation of RNA family, is found to be essential in the blood vessel development and postnatal myelination in central nervous system (Woo et al., Oncogene 28:1176–1186, 2009; Lu et al., Nucleic Acids Res 31(15):4616–4624, 2003; Bohnsack et al., Genesis 44(2):93–104, 2006). However, its wide expression pattern suggests other fundamental roles in vivo (Kondo et al., Mamm Genome 10(7):662–669, 1999). To facilitate the understanding of QKI function in various systems, we prepared the polyclonal and monoclonal antibodies against QKI. To obtain the antigen, recombinant His-tagged QKI was expressed in Escherichia coli and highly purified by Ni2+-chelated column combined with hydrophobic and ion exchange methods. Following three types of immunizations with different adjuvants, including Freund’s, PAGE gel, and nitrocellulose membrane, only the antiserum produced with Freund’s adjuvant is effective for Western blot detection. Several McAb clones are able to recognize both endogenous and over-expressed QKI with high affinity in Western blot and immunofluorescence. The specificity of Ab was validated as weakening, and no specific signals were observed in cells with QKI knocking down. Immunohistochemistry analysis further showed positive staining of QKI in kidney where QKI mRNA was abundantly expressed, ensuring the wide applications of the QKI Abs in the ongoing mechanistic studies.  相似文献   
72.
73.
Feng G  Jiang L  Wen P  Cui Y  Li H  Hu D 《The Analyst》2011,136(22):4822-4829
A new ion-exchange adsorbent (IEA) derived from Fe(3)O(4)/SiO(2)-GPTMS-DEAE with paramagnetic properties was prepared. Fe(3)O(4) nanoparticles were firstly prepared in water-in-oil microemulsion. The magnetic Fe(3)O(4) particles were modified in situ by hydrolysis and condensation reactions with tetraethoxysilane (TEOS) to form the core-shell Fe(3)O(4)/SiO(2). The modified particles were further treated by 3-glycidoxypropyltrimethoxysilane (GPTMS) to form Fe(3)O(4)/SiO(2)-GPTMS nanoparticles. Fe(3)O(4)/SiO(2)-GPTMS-DEAE nanoparticles (IEA) were finally obtained through the condensation reaction between the Cl of diethylaminoethyl chloride-HCl (DEAE) and the epoxy groups of GPTMS in the Fe(3)O(4)/SiO(2)-GPTMS. The obtained IEA has features of paramagnetic and ion exchange properties because of the Fe(3)O(4) nanoparticles and protonated organic amine in the sample. The intermediates and final product obtained in the synthesis process were characterized. The separation result of genomic DNA from blood indicated that Fe(3)O(4)/SiO(2)-GPTMS-DEAE nanoparticles have outstanding advantages in operation, selectivity, and capacity.  相似文献   
74.
We contribute to the classification of finite dimensional algebras under stable equivalence of Morita type. More precisely we give a classification of Erdmann’s algebras of dihedral, semi-dihedral and quaternion type and obtain as byproduct the validity of the Auslander-Reiten conjecture for stable equivalences of Morita type between two algebras, one of which is of dihedral, semi-dihedral or quaternion type.  相似文献   
75.
In this paper, a modified semidiscrete central-upwind scheme is derived for the scalar conservation laws with a discontinuous flux function in space. The new scheme is based on dealing with the phase transition at the stationary discontinuity, where the unknown variable function is not continuous, but the flux function is continuous. The main advantages of the new scheme are the same as them of the original semidiscrete central-upwind scheme. Numerical results are displayed to illustrate the efficiency of the methods.  相似文献   
76.
Tan Y  Yu J  Cui Y  Yang Y  Wang Z  Hao X  Qian G 《The Analyst》2011,136(24):5283-5286
A novel fluorescence chemosensor based on 2,6-dicarbonylpyridine was designed and synthesized and its photophysical properties were characterized. Upon coordination of Co(2+) by the central 2,6-dicarbonylpyridinyl functional group, the chemosensor 2,6-bis(4-diphenylamino-styrylcarbonyl)pyridine (PhPy) showed nearly complete fluorescence quenching, while no fluorescence response was seen towards other competing cations. The experimental results show the chemosensor is highly selective and sensitive towards Co(2+) in the presence of competing ions, even in the ppb range. Job plot analysis was carried out and the results suggested that the binding of PhPy and Co(2+) was probably a 2?:?1 stoichiometry.  相似文献   
77.
The first near-infrared luminescent ytterbium metal-organic framework has been realized for the highly selective and sensitive sensing of small molecules.  相似文献   
78.
A doubly interpenetrated semiconducting MOF Zn(4)O(2,6-NDC)(3)(DMF)(1.5)(H(2)O)(0.5)·4DMF·7.5H(2)O (UTSA-38) of a cubic net has been constructed, which exhibits photocatalytic activity for the degradation of methyl orange in aqueous solution.  相似文献   
79.
研究不确定因素对炸药在混凝土复合介质中爆炸的影响,并在不确定因素的影响下进行优化设计。用区间数模型来描述系统中的不确定参数,建立相应的区间数优化模型;通过高维代理模型的引入,以及对其中二层嵌套优化问题进行直接解耦,得到了一种高效的求解方法。研究表明:算法经过8个迭代步收敛到最优解,最优解得到的最佳炸药装填深度约为64cm,最佳姿态角约为30°;经过三个迭代步就能迅速定位到最优解附近。算法保证了在最大化毁伤面积的同时,尽量地追求不确定因素影响最小,即综合考虑了毁伤最大和偏差最小。该不确定优化设计方法能有效地推广到相关领域的优化设计,为处理爆炸系统的装药设计和爆炸初始状态参数设计等方面提供了新思路。  相似文献   
80.
This paper studies the structural monostability and structural cycle‐stability of Boolean networks (BNs). Firstly, the structural‐equivalent Boolean networks are converted to the algebraic forms by using the semitensor product of matrices. Secondly, the concepts of structural monostability and structural cycle‐stability for Boolean networks are proposed. On the basis of the algebraic forms of structural‐equivalent Boolean networks, some necessary and sufficient conditions are presented for the structural monostability and structural cycle‐stability of Boolean networks. Finally, an illustrative example is worked out to show the effectiveness of the obtained results.  相似文献   
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