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XIAO Chang-jiang SUN Ming ZHOU Hong-yan LIU Sui-xin LONG Kai-chao HE Fei LI Tong 《中南工业大学学报(英文版)》2005,12(Z1)
Objective Study on the effect of NF-κB in ox-LDL injured HUVEC-304 and the intervention with the serum of Tongmai Decoction. Methods Tongmai Decoction herbage-contained serum was made by the serum pharmacology methods, then the HUVEC-304 cells were divided into 5 groups and incubated for 24 h: 1) normal group;2) fetal calf serum group; 3) ox-LDL group; 4) simvastatin group; 5) Tongmai Decoction group. RT-PCR was used to determine the mRNA of NF-κB in the cells, Western Blot Assay was used to determine the protein content of NF-κB in the cells. Results 1) Compared with the cells in normal group and serum control group , the endothelial cells in ox-LDL group are seriously injured, while those in Tongmai Decoction group grow better; 2) Compared with the cells in normal group and fetal calf serum group, the expressions of NF-κB gene and protein are up-regulated in ox-LDL group(P<0.05, P<0.01); 3) Compared with the cells in ox-LDL group, the expression of NF-κB gene and protein in Tongmai Decoction group are significantly down-regulated, there is no difference between Tongmai Decoction group and simvastatin group(P>0.05). Conclusion Tongmai Decoction can protect the injured endothelial cells, up-regulate the expressions of NF-κB gene and protein content. 相似文献
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Shaofeng Wang Jianwei Xu Yuejin Tong Lin Wang Chaobin He 《Polymer International》2005,54(9):1268-1274
A novel cholesterol‐imprinted polymer (CMIP‐H) was prepared by a hybrid method of covalent imprinting and non‐covalent imprinting. This approach involves the copolymerization of a template‐containing monomer, cholesteryl 2‐hydroxyethyl methacrylate carbonate, and a cross‐linker, followed by hydrolysis to afford a flexible guest‐binding site accompanied with the easy and efficient removal of a ‘sacrificial spacer’. The effect of solvent on the binding capacity of CMIP‐H towards cholesterol was studied, indicating that a good binding capacity towards cholesterol could be achieved in a less‐polar solvent. The binding experiments of CMIP‐H towards a series of structural analogues of cholesterol, including cholesterol acetate, progesterone and stigmasterol, were carried out in hexane. The results showed that CMIP‐H almost did not bind cholesterol acetate at all because the hydrogen‐bonding site is blocked. It exhibited a similar binding towards both cholesterol and stigmasterol, but much higher binding towards progesterone. Copyright © 2005 Society of Chemical Industry 相似文献
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Dongchang Sun Liyong Tong 《International journal for numerical methods in engineering》2004,60(11):1911-1932
A novel finite element model is presented for static and dynamic analysis of composite plates integrated with a laminated piezoelectric layer, a host laminated composite plate and an adhesive layer between them. A new adhesive element is developed which includes both peel and shear effects in the adhesive layer based on first‐order shear deformation plate theory. The thin adhesive layer between the piezoelectric layer and the host plate is modelled by assuming that it carries constant shear and peel strains throughout its thickness. In addition, a weighted static shape control scheme for finding the optimal voltage distribution for static shape control is given. By selecting different weighting matrices, a variety of items such as displacements, slopes, curvatures, strains and even generalized forces, can be included in finding the optimal actuating voltage for static shape control. The present model is validated by comparing with those results available in the literature. The numerical results show that the weighted linear least method can give a satisfactory voltage distribution to best match the desired shape. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Hui Chen D.T.K. Tong 《Photonics Technology Letters, IEEE》2005,17(4):801-803
Symmetric interference in two-dimensional multimode silicon waveguides is experimentally investigated. For a 100/spl times/100 /spl mu/m/sup 2/ cross section, 2700-/spl mu/m-long waveguide fabricated on silicon-on-insulator substrate, an 8/spl times/8 matrix of replicated images with high contrast ratio is demonstrated for 1530-1570 nm wavelength range. Symmetric interference results in reduced device length, and the actual device length is consistent with the theoretical expectation. The device also exhibits stable imaging in terms of good loss uniformity, and low wavelength and polarization dependencies among the replicated images. 相似文献
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The ennoblement of corrosion potential (Ecorr) of passive metal immersed in seawater was investigated with electrochemical technology and epifluorescence microscopy. The in situ observation showed that the bacteria number increased on the metal surface according to an exponential law which was in the same way with the ennoblement of Ecorr. At the same time, the anodic polarization current of high‐Mo stainless steel decreased in the initial days. According to the mix‐potential theory and the characteristics of polarization curves of high‐Mo steel in natural seawater, the ennoblement of corrosion potential may be induced by the decrease of the passive current density. 相似文献
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基于DSP+CPLD的高精度信号发生器 总被引:2,自引:0,他引:2
介绍了基于直接数字式频率合成(DDS)原理的全数字信号发生器(DSP),利用DSP芯片快速、高精度的运算优势以及CPLD芯片灵活的编程逻辑、大容量存储功能的特点,采用通用可编程芯片以及数字波形合成技术,形成高稳定、高精度、高动态的数字合成信号.该信号发生器可产生0~25 kHz的正弦波、三角波和方波,输出电压峰峰值为0~5 V,频率步进1 Hz,幅度步进0.001 V. 相似文献
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