排序方式: 共有180条查询结果,搜索用时 0 毫秒
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Raisi F Blizard BA Raissi Shabari A Ching J Kintz GJ Mitchell J Lemoff A Taylor MT Weir F Western L Wong W Joshi R Howland P Chauhan A Nguyen P Petersen KE 《Journal of separation science》2004,27(4):275-283
The growing importance of analyzing the human genome to detect hereditary and infectious diseases associated with specific DNA sequences has motivated us to develop automated devices to integrate sample preparation, real-time PCR, and microchannel electrophoresis (MCE). In this report, we present results from an optimized compact system capable of processing a raw sample of blood, extracting the DNA, and performing a multiplexed PCR reaction. Finally, an innovative electrophoretic separation was performed on the post-PCR products using a unique MCE system. The sample preparation system extracted and lysed white blood cells (WBC) from whole blood, producing DNA of sufficient quantity and quality for a polymerase chain reaction (PCR). Separation of multiple amplicons was achieved in a microfabricated channel 30 microm x 100 microm in cross section and 85 mm in length filled with a replaceable methyl cellulose matrix operated under denaturing conditions at 50 degrees C. By incorporating fluorescent-labeled primers in the PCR, the amplicons were identified by a two-color (multiplexed) fluorescence detection system. Two base-pair resolution of single-stranded DNA (PCR products) was achieved. We believe that this integrated system provides a unique solution for DNA analysis. 相似文献
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Cobalt oxide nanoparticles (Co3O4-NPs) were synthesized by aqueous extract of Artemisia vulgaris plant at 50°C. The biosynthesized extract mediated Co3O4-NPs were characterized through different methods containing FT-IR (Fourier transform infrared spectroscopy), FESEM (Field emission scanning electron microscopy), EDS (Energy-dispersive x-ray spectroscopy), and XRD (x-ray diffraction). Co3O4-NPs as an efficient and practical catalyst was employed for the electrochemical oxidation of formaldehyde; which was an irreversible charge transfer controlled by mass transfer. The coefficients of electron transfer and diffusion were 0.87 and 0.122 cm2/s for formaldehyde oxidation on Co3O4 electrode, respectively. The formation of the CoOOH species during potential sweeping appears to be involved in the catalytic activity of the Co3O4 toward formaldehyde oxidation. 相似文献
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Jiang B Xu D Allocco J Parish C Davison J Veillette K Sillaots S Hu W Rodriguez-Suarez R Trosok S Zhang L Li Y Rahkhoodaee F Ransom T Martel N Wang H Gauvin D Wiltsie J Wisniewski D Salowe S Kahn JN Hsu MJ Giacobbe R Abruzzo G Flattery A Gill C Youngman P Wilson K Bills G Platas G Pelaez F Diez MT Kauffman S Becker J Harris G Liberator P Roemer T 《Chemistry & biology》2008,15(4):363-374
Natural products provide an unparalleled source of chemical scaffolds with diverse biological activities and have profoundly impacted antimicrobial drug discovery. To further explore the full potential of their chemical diversity, we survey natural products for antifungal, target-specific inhibitors by using a chemical-genetic approach adapted to the human fungal pathogen Candida albicans and demonstrate that natural-product fermentation extracts can be mechanistically annotated according to heterozygote strain responses. Applying this approach, we report the discovery and characterization of a natural product, parnafungin, which we demonstrate, by both biochemical and genetic means, to inhibit poly(A) polymerase. Parnafungin displays potent and broad spectrum activity against diverse, clinically relevant fungal pathogens and reduces fungal burden in a murine model of disseminated candidiasis. Thus, mechanism-of-action determination of crude fermentation extracts by chemical-genetic profiling brings a powerful strategy to natural-product-based drug discovery. 相似文献
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Mohammad Ali Kamyabi Fatemeh Soleymani‐Bonoti Fariba Alirezaei Rahman Bikas Nader Noshiranzadeh Marzieh Emami Marta S. Krawczyk Tadeusz Lis 《应用有机金属化学》2019,33(12)
A new dinuclear cobalt(III) coordination compound, [Co2L(μ‐N3)(N3)2]·CH3OH ( 1 ), was synthesized and characterized by elemental analysis, spectroscopic methods, and single‐crystal X‐ray analysis in which H3L is a heptadentate ligand obtained by the condensation of triethylenetetramine with 5‐bromo‐2‐hydroxybenzaldehyde. X‐ray analysis revealed that two cobalt(III) ions have distorted octahedral geometry and are connected together by a phenoxy and an azide bridging ligand. The catalytic activity of compound 1 for oxygen (O2) reduction reaction was investigated. Compound 1 can efficiently catalyze the reduction of O2 by a weak electron donor, ferrocene (Fc), at the polarized water–1,2‐dichloroethane interface. It was found that compound 1 can catalyze O2 reduction to H2O2, whereas in the presence of Fc, it can catalyze the reduction of O2 to water. 相似文献
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Ali Ramazani Mehdi Khoobi Fariba Sadri Roghayeh Tarasi Abbas Shafiee Hamideh Aghahosseini Sang Woo Joo 《应用有机金属化学》2018,32(1)
Palladium immobilized magnetic nanoFe3O4@hyperbranched polyethylenimine (Fe3O4@HPEI.Pd) was prepared according to a simple and cost effective pathway and it was employed as a new efficient and selective organic–inorganic hybrid nanocatalyst for the aqueous oxidation of primary and secondary alcohols to their corresponding products in good yields applying oxone (potassium hydrogen monopersulfate) and H2O2 as an oxidant at room temperature. Moreover, the catalytic system was reused at least 13 times without significant loss of activity. The complete characterization of this efficient nanocatalyst was investigated by FTIR, UV–Vis, TEM, SEM, XRD, TGA, VSM, ICP and EDX techniques. 相似文献
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Boehmite (BO) nanoparticles (NPs) were prepared via the injection of aqueous NaOH solution to aqueous aluminum nitrate solution at room temperature. Afterwards, a new complex of copper was immobilized on BO-NPs (Cu-Guanidine@BO-NPs). This heterogeneous nanocatalyst was used as a practical, recyclable, chemo and homoselective nanocatalyst in the organic processes, i.e. the preparation of tetrazole five-membered heterocycles and chemoselective sulfoxidation of sulfides using H2O2 as oxidant. In this sense, the prepared nanocatalyst was characterized by AAS, N2 adsorption–desorption isotherms, WDX, EDS, SEM, and TGA techniques. The reusability of this catalyst was investigated in the described organic reactions for several runs without notable loss of its catalytic activity. Moreover, all of the tetrazole and sulfoxide derivatives were isolated in high Turn Over Number (TON) and Turn Over Frequency (TOF) numbers indicating the high activity and selectivity of Cu-Guanidine@BO-NPs in the described reactions. 相似文献