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991.
Khiev P Oh SR Chae HS Kwon OK Ahn KS Chin YW Lee HK 《Chemical & pharmaceutical bulletin》2011,59(3):382-384
Bioactivity-guided isolation on a n-hexane-soluble fraction of Thyrsanthera suborbicularis led to the isolation of a new rosane-type diterpene, 19-hydroxy-1(10), 15-rosadiene (1), along with three known compounds, taraxerol, acetyl aleuritolic acid, and spathulenol. The structures of isolated compounds were determined by interpretation of NMR spectroscopic data and mass spectrometry. Compound 1 demonstrated significantly inhibitory activity on nitric oxide production in RAW264.7 lipopolysaccharide (LPS)-activated mouse macrophages with an IC(50) value of 2.91 μg/ml via the suppression of inducible nitric oxide synthase (iNOS) mRNA expression. 相似文献
992.
β-amino-α,α-dichloro sulfones 3 are prepared by the reaction of vinyl sulfone 1 with primary or secondary amines 2in the presence of CCI4 and NaH. 相似文献
993.
Reaction of lithio anion derived from diethyl alkanephosphonate in the presence of 2 eq. of n-BuLi with benzenesulfonyl chloride gives directly the corresponding diethyl-1-chloro-1-lithioalkanephosphonate, which reacts in situ with carbonyl compounds followed by intramolecular substitution reaction to give 1,2-epoxyalkanephosphonates. 相似文献
994.
[Methoxy(phenylthio)methyl]trimethylsilane reacted with arenes and alk-1-enes in the presence of a Lewis acid to give the Friedel-Crafts product and the ene product, respectively. 相似文献
995.
Chul‐Ho Ok Byoung‐Yong Kim Byeong‐Yun Oh Young‐Hwan Kim Kang‐Min Lee Hong‐Gyu Park 《Liquid crystals》2013,40(12):1373-1377
The nematic liquid crystal alignment capability and electro‐optical (EO) performance characteristics of in‐plane switching (IPS) cells were first demonstrated on organic hybrid overcoat layers via ion beam irradiation. Usually the organic hybrid overcoat is used as the material for making a plate alignment layer in a colour filter process. To characterise the organic hybrid overcoat layer, we analysed the surface composition of the organic hybrid overcoat by X‐ray photoelectron spectroscopy. The results show that the intensity of C = O and C–O bonding undergoes a change corresponding to the changes in energy of the ion beam exposure. Moreover, EO performance characteristics of IPS cells on the organic hybrid overcoat layer via ion beam irradiation were observed to have similar characteristics to the polyimide. 相似文献
996.
Soon Mo Choi Deepti Singh Yong Woo Cho Tae Hwan Oh Sung Soo Han 《Colloid and polymer science》2013,291(5):1121-1133
The aim of this work is to develop a novel biocompatible drug delivery carrier and tissue engineering scaffold with the ability of controlled drug release and also tissue regeneration. We have synthesized N-(2-hydroxypropyl)methacrylamide and 2-(dimethylamino)ethyl methacrylate copolymer-based hydrogels loaded with doxorubicin and tested in vitro. The manifestation of temperature sensitivity is noted with a sharp decrease or increase in hydrogel optical transparency that happens with the temperature exceeding a critical transition value. The drug release profile exhibited pH-sensitive behavior of the hydrogel. The hydrolytic degradation of gel and in vitro studies of polymer–doxorubicin conjugate and doxorubicin release from hydrogel matrix indicated that hydrogels were stable under acidic conditions (in buffers at pH 4.64 and 6.65). In both drug forms, polymer–doxorubicin conjugate and free doxorubicin could be released from the hydrogel scaffold at a rate depending directly on either the rate of drug diffusion from the hydrogel or rate of hydrogel degradation or at rate controlled by a combination of the both processes. In vitro analysis showed homogenous cell attachment and proliferation on synthesized hydrogel matrix. In vivo implantation demonstrated integration of the gel with the surrounding tissue of mice within 2 weeks and prominent neo-angiogenesis observed in the following weeks. This multifunctional hydrogels can easily overcome biological hurdles in the in vivo conditions where the pH range changes drastically and could attain higher site-specific drug delivery improving the efficacy of the treatment in various therapeutical applications, especially in cancer therapy, and could also be used as tissue engineering scaffold due to its porous interconnected and biocompatible behavior. 相似文献
997.
V. Janaki K. Vijayaraghavan Byung-Taek Oh A. K. Ramasamy Seralathan Kamala-Kannan 《Cellulose (London, England)》2013,20(3):1153-1166
The aim of the study was to analyze the potential application of cellulose/polyaniline (Ce/Pn) nanocomposite for the treatment of synthetic reactive dye bath effluent. The Ce/Pn composite was synthesized by chemical oxidative polymerization of aniline. A central composite experimental design, a most popular design of response surface methodology, was applied to optimize the level of variables, namely, cellulose and polyaniline, to get the best response on dye removal. Biological transmission electron microscopy studies reveal that the cellulose particles were uniformly distributed on the nanocomposite. The results of the batch experiment studies indicate that Ce/Pn nanocomposite removed 95.9, 91.9, 92.7, and 95.7 % of RBBR, RO, RV, and RBK, respectively, and it decolorized 82 % of dye bath effluent. However, the presence of the salts reduced the adsorption rate of the dyes. The Langmuir model and pseudo first-order rate expression exhibited satisfactory fit to adsorption data of single component. 相似文献
998.
999.
D. Kalyanasundaram J.-H. Kim W.-H. Yeo K. Oh K.-H. Lee M.-H. Kim S.-M. Ryew S.-G. Ahn D. Gao G. A. Cangelosi J.-H. Chung 《Analytical and bioanalytical chemistry》2013,405(6):1977-1983
Simple and rapid extraction of human genomic DNA remains a bottleneck for genome analysis and disease diagnosis. Current methods using microfilters require cumbersome, multiple handling steps in part because salt conditions must be controlled for attraction and elution of DNA in porous silica. We report a novel extraction method of human genomic DNA from buccal swab and saliva samples. DNA is attracted onto a gold-coated microchip by an electric field and capillary action while the captured DNA is eluted by thermal heating at 70 °C. A prototype device was designed to handle four microchips, and a compatible protocol was developed. The extracted DNA using microchips was characterized by qPCR for different sample volumes, using different lengths of PCR amplicon, and nuclear and mitochondrial genes. In comparison with a commercial kit, an equivalent yield of DNA extraction was achieved with fewer steps. Room-temperature preservation for 1 month was demonstrated for captured DNA, facilitating straightforward collection, delivery, and handling of genomic DNA in an environment-friendly protocol. Figure
Portable microtip device for human genomic DNA extraction 相似文献
1000.