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51.
Co‐Co3O4/carbon nanotube/carbon foam (Co‐Co3O4/CNT/CF) nanocomposites were prepared by soaking melamine foam into a solution of Co(NO3)2·6H2O, followed by calcination in N2 and air in sequence. The obtained Co‐Co3O4/CNT/CF nanocomposites were characterized with scanning electron microscopy and cyclic voltammetry. It was found that Co3O4 nanoparticles were grown on the external of CF successfully, while CNTs were grown on the surfaces of CF in a large amount, which further improved the electrical conductivity of the. The prepared Co‐Co3O4/CNT/CF nanocomposites were then used to construct nonenzymatic sensor to detect glucose in alkaline solution. The sensor showed detection range from 1.2 μM to 2.29 mM with a detection limit of 0.4 μM (S/N =3) and a high sensitivity of 637.5 μA?1 cm?2. The developed sensor also showed an instant response, favorable reproducibility, and high selectivity. The results attest that Co‐Co3O4/CNT/CF composites have great potential in the development of nonenzymatic sensors for glucose. 相似文献
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In this article, a simple, effective chemiluminescence (CL) method for the detection of methylparaben (MP) in cosmetic samples was developed based on an IO4?–H2O2–carbon nitrogen quantum dots (CNQDs) system without a separation process. The results indicated that the redox reaction between periodate and hydrogen peroxide released hydroxide radicals and superoxide radical anions in the presence of bicarbonate. These two radicals were responsible for the formation of excited luminophor CNQD* with a maximum wavelength at 480 nm. Due to the competitive reaction with hydroxide radicals, CL intensity was markedly diminished in the presence of MP. The relative standard deviation in the intraday assay was below 5.5% (n = 9), and the detection limit was as low as 0.50 μmol/L. The proposed method allowed for the successful, selective determination of MP in cosmetics. 相似文献
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Kyungtae Kim Dinh Truong Nguyen Minkyung Choi Jin-Hoi Kim Han Geuk Seo Hailu Dadi 《Animal biotechnology》2013,24(3):243-250
To confirm the beneficial effects of alpha (1,2)-fucosyltransferase (FUT1) M307 A on piglet survival on commercial farms, we performed PCR-RFLP analysis of FUT1 M307 in successfully marketed (n = 245) and disease affected/deceased pigs during weaning (n = 252) at a commercial farm. We also evaluated the FUT1 genotypes of 190 healthy pigs from three different genetic backgrounds. The distribution of genotypes differed between the successfully marketed and disease affected/deceased pig groups. The frequency of the A allele, associated with resistance to edema and post-weaning diarrhea, was higher in the post-weaning survival group (0.21) than in the non-survival group (0.16, P < 0.05). The odds ratio for piglet survival between AA and GG genotypes was 1.98; thus, piglet survival for individuals with the AA genotype was almost two-fold greater than for GG individuals. The FUT1 gene polymorphism can be used as an effective marker for selection programs to improve post-weaning piglet survival. 相似文献
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Othman Wan-Norafikah Wasi Ahmad Nazni Han Lim Lee Pawanchee Zainol-Ariffin Mohd Sofian-Azirun 《Saudi Journal of Biological Sciences》2013,20(3):241-250
The resistance status towards permethrin among the laboratory strain, the permethrin-selected strain and four field strains of Culex quinquefasciatus collected in Kuala Lumpur, Malaysia was determined using three standard laboratory methods: WHO larval bioassay, WHO adult bioassay and biochemical microplate assay. Cx. quinquefasciatus permethrin-selected strain larvae were the least susceptible to permethrin with a resistance ratio of 47.28-folds, whereas all field strain larvae of the same species were tolerant to permethrin with resistance ratios of more than 3-folds. In contrast, in adult stage, the permethrin exposed permethrin-selected strain (resistance ratio = 1.27) was found to be more susceptible to permethrin than all permethrin-exposed field strains (resistance ratios = 2.23–2.48). Complete mortalities for all strains of Cx. quinquefasciatus adults proved the effectiveness of the synergist; piperonyl butoxide (PBO). For the biochemical microplate assay, the reduction of the mean optical density of elevated oxidase activity of three field strains upon exposure to PBO confirmed the association between oxidase activity and permethrin tolerance. On the other hand, irregular patterns of the mean optical density of elevated oxidase activity in the laboratory strain, permethrin-selected strain and Jalan Fletcher strain illustrated the gene variation within these mosquito colonies as well as the involvement of other enzyme activities in the permethrin resistance occurred. 相似文献
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Cancer marker discovery is an emerging topic in high-throughput quantitative proteomics. However, the omics technology usually generates a long list of marker candidates that requires a labor-intensive filtering process in order to screen for potentially useful markers. Specifically, various parameters, such as the level of overexpression of the marker in the cancer type of interest, which is related to sensitivity, and the specificity of the marker among cancer groups, are the most critical considerations. Protein expression profiling on the basis of immunohistochemistry (IHC) staining images is a technique commonly used during such filtering procedures. To systematically investigate the protein expression in different cancer versus normal tissues and cell types, the Human Protein Atlas is a most comprehensive resource because it includes millions of high-resolution IHC images with expert-curated annotations. To facilitate the filtering of potential biomarker candidates from large-scale omics datasets, in this study we have proposed a scoring approach for quantifying IHC annotation of paired cancerous/normal tissues and cancerous/normal cell types. We have comprehensively calculated the scores of all the 17219 tested antibodies deposited in the Human Protein Atlas based on their accumulated IHC images and obtained 457110 scores covering 20 different types of cancers. Statistical tests demonstrate the ability of the proposed scoring approach to prioritize cancer-specific proteins. Top 100 potential marker candidates were prioritized for the 20 cancer types with statistical significance. In addition, a model study was carried out of 1482 membrane proteins identified from a quantitative comparison of paired cancerous and adjacent normal tissues from patients with colorectal cancer (CRC). The proposed scoring approach demonstrated successful prioritization and identified four CRC markers, including two of the most widely used, namely CEACAM5 and CEACAM6. These results demonstrate the potential of this scoring approach in terms of cancer marker discovery and development. All the calculated scores are available at http://bal.ym.edu.tw/hpa/. 相似文献