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The authenticity and traceability of meat products are issues of primary importance to ensure food safety. Unfortunately, food adulteration (e.g. the addition of inexpensive cuts to minced meat products) and mislabelling (e.g. the inclusion of meat from species other than those declared) happens frequently worldwide. The aim of this study was to apply a droplet digital PCR assay for the detection and quantification (copies μL−1) of the beef, pork, horse, sheep, chicken and turkey in meat products. The analysis conducted on commercial meat showed the presence of traces of DNA from other animal species than those declared. We show that the method is highly sensitive, specific and accurate (accuracy = 100%). This method could be adopted by competent food safety authorities to verify compliance with the labelling of meat products and to ensure quality and safety throughout the meat supply chain, from primary production to consumption.  相似文献   
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日本国家高级工业科学与技术研究所的一个研究组正在利用快速移动的细菌来驱动微转子马达,这是第一个在无机材料中加进了细菌的微机械器件。这种生物分子马达能比传统的马达更有效的将化学能转化为机械能,还能在大型结构中发挥自修复和自组织的潜能,有望用在微型机器人和微小电子系统中。  相似文献   
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An LC-ESI-MS/MS method was developed for the quantitative detection of postharvest fungicide residues in citrus juices and reported in this paper. The analyses of thiabendazole (TBZ), carbendazim (MBC), thiophanate methyl (TPM), imazalil (IMZ) and prochloraz (PCZ) residues were performed by using a gradient elution in conjunction with positive ionization mode electrospray ionization tandem mass spectrometry. Fungicides were extracted from citrus juices with recoveries ranging from 79.8 to 101.2% and relative standard deviation better than 15%. The quantification limits ranged from 0.01 μg/kg IMZ to 0.06 μg/kg for MBC. The LC-MS-MS method was applied to commercial citrus juices, detecting MBC, TBZ and IMZ residues in the 90% of the samples. Prochloraz residues were detected only in one of the multifruit juice (orange, lemon and carrot) samples.  相似文献   
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A new technique to obtain microporous hydrogels was realised. It permits us to obtain a microporous structure directly on the already cross-linked hydrogel. It consists in stratifying the already cross-linked hydrogel on to a filter with known porosity and forcing the CO2 bubbles, derived from the addition of HCl to a porogen salt (NaHCO3), to cross through the filter first and then the matrix. By changing the porosity of the filter, it was possible to modulate the porous morphology of the hydrogels. The polysaccharides selected were hyaluronane, alginate, and carboxymethylcellulose. The influence of the porous morphology on the physico-chemical properties of the gel has been evaluated by FT-IR, FRAP, calorimetric, water uptake, and rheological analysis.  相似文献   
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In this pilot study, ethosomes and transethosomes were investigated as potential delivery systems for cholecalciferol (vitamin D3), whose deficiency has been correlated to many disorders such as dermatological diseases, systemic infections, cancer and sarcopenia. A formulative study on the influence of pharmaceutically acceptable ionic and non-ionic surfactants allowed the preparation of different transethosomes. In vitro cytotoxicity was evaluated in different cell types representative of epithelial, connective and muscle tissue. Then, the selected nanocarriers were further investigated at light and transmission electron microscopy to evaluate their uptake and intracellular fate. Both ethosomes and transethosomes proven to have physicochemical properties optimal for transdermal penetration and efficient vitamin D3 loading; moreover, nanocarriers were easily internalized by all cell types, although they followed distinct intracellular fates: ethosomes persisted for long times inside the cytoplasm, without inducing subcellular alteration, while transethosomes underwent rapid degradation giving rise to an intracellular accumulation of lipids. These basic results provide a solid scientific background to in vivo investigations aimed at exploring the efficacy of vitamin D3 transdermal administration in different experimental and pathological conditions.  相似文献   
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The 9139 follow-up records of 438 myasthenia gravis (MG) patients were reviewed. Excluding those patients who were diagnosed 5 or more years after symptom onset (n = 37) and those who experienced only oculomotor symptoms throughout follow-up (n = 21), there were 380 patients. A survival analysis approach was used to assess the influence of prognostic factors on the following endpoints: (a) stable complete remission, (b) complete remission of at least 6 months and (c) pharmacological remission of at least 6 months. Early diagnosis was associated with a better prognosis with respect to all endpoints. Thymectomy also improved the prognosis but only for those patients without thymoma. Later MG onset was associated with a higher tendency to achieve pharmacological remission.  相似文献   
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