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1.
Swellable microneedles (SMNs) are made of hydrogels and can deliver drug with controlled delivery rate by the cross-link density of the hydrogel. In this study, an acryl resin-based SMNs was developed for poorly water-soluble drugs. The making process of the SMNs is very simple and only need 60?min. The SMNs has high mechanical strength and is not easily broken. In-vitro release of SMNs-loaded model drug, granisetron base (GRB), was investigated. The results showed that seven days controlled release of GRB was obtained when SMNs contained pore-foaming agents (1.5% dicalcium phosphate (CaHPO4) and 1.5% polyvinylpyrrolidone (PVP)). The maximum amount delivered into skin was 86.158?±?7.82% of the initial GRB (2.1?mg) loaded on SMNs preparation. Pharmacokinetics study in rats indicated a dose-dependent profile of plasma GRB concentrations and that the controlled release of 2.1?mg dose was observed for 144?hours. In conclusion, these SMNs provided a potential minimally invasive route for controlled-release systemic delivery of poorly water-soluble drugs.  相似文献   
2.
A multi-residue HPLC–ESI–MS/MS method has been developed for the simultaneous extraction, detection and confirmation of the 11 coccidiostats referenced by Regulation 2009/8/EC (lasalocid sodium, narasin, salinomycin sodium, monensin sodium, semduramicin sodium, maduramicin ammonium alpha, robenidine hydrochloride, decoquinate, halofuginone hydrobromide, nicarbazin, and diclazuril) in feedstuffs at carry-over level. The sensitivity of the method allows quantification and confirmation for all coccidiostats below target concentration. The method was in-house validated and meets all criteria of European legislation (2002/657/EC). The precision of the method was determined under repeatability and within-laboratory reproducibility conditions; RSDr and RSDR were below the maximum permitted values for every tested concentration. The specificity was checked by analysing representative blank samples and blank samples fortified with potentially interfering substances (benzimidazoles, corticosteroides, triphenylmethane dyes, quinolones, nitrofurans, nitroimidazoles, phenicols); no interference were found. Concerning quantification, a quadratic regression model was fitted to every calibration curve with a regression coefficient r 2 above 0.99 on each data set. Finally, the expanded uncertainty U was calculated with data obtained within the laboratory while applying the method during validation and in routine tests.  相似文献   
3.
1997年发现H5N1禽流感病毒(H5N1 AIV)跨越物种障碍使人感染,致死率60%,表明H5N1是一强致病力的流感病毒。H7N9禽流感病毒是2013年3月在我国上海和安徽发现并感染人的一种新的禽流感病毒株。我国立即采取了重大措施加以控制。H7N9禽流感的出现受到了世界许多国家和世界卫生组织的严重关注。本文介绍了禽流感病毒的分类和命名法,及以往H7禽流感的流行和人感染病例,讨论了H7亚型致病力的机制,综述了H7N9流感病毒及抗病毒药物研究进展,为H7N9禽流感的预防、治疗的研究和新药开发提供有益的参考。  相似文献   
4.
本文阐述了分子蒸馏技术的基本原理和特点,比较了分子蒸馏和传统精馏的特点。介绍了近年来分子蒸馏技术在中药有效成分提取和西药成品绩及中间体分离纯化中的应用。  相似文献   
5.
Chemical safety of meat and meat products   总被引:3,自引:0,他引:3  
Since the Second World War the consumer behaviour in developed countries changed drastically. Primarily there existed the demand for sufficient food after a period of starvation, afterwards the desire for higher quality was arising, whereas today most people ask for safe and healthy food with high quality. Therefore a united approach comprising consistent standards, sound science and robust controls is required to ensure consumers' health and to maintain consumers' confidence and satisfaction. Chemical analysis along the whole food chain downstream (tracking) from primary production to the consumer and upstream (tracing) from the consumer to primary production is an important prerequisite to ensure food safety and quality. In this frame the focus of the following paper is the “chemical safety of meat and meat products” taking into account inorganic as well as organic residues and contaminants, the use of nitrite in meat products, the incidence of veterinary drugs, as well as a Failure Mode and Effect Analysis (FMEA) system assessing (prioritizing) vulnerable food chain steps to decrease or eliminate vulnerability.  相似文献   
6.
超声辅助提取技术在天然产物提取中的应用   总被引:5,自引:0,他引:5  
简述超声辅助提取技术提高活性成分提取率的作用及原理,对超声辅助提取技术在天然产物有效成分(生物碱、黄酮、蒽醌、皂甙、植物油)提取方面,以及在农残分析样品提取方面的应用研究成果进行概述,并指出当前研究中存在的问题和今后的研究方向。  相似文献   
7.
Discoveries of tumor-resistant pharmacological drugs have mainly resulted from screening of natural products and their analogs. Some are also discovered incidentally when studying organisms. The great biodiversity of microorganisms raises the possibility of producing secondary metabolites (e.g., mevastatin, lovastatin, epothilone, salinosporamide A) to cope with adverse environments. Recently, natural plant pigments with anti-tumor activities such as β-carotene, lycopene, curcumin and anthocyanins have been proposed. However, many plants have a long life cycle. Therefore, pigments from microorganisms represent another option for the development of novel anti-tumor drugs. Prodigiosin (PG) is a natural red pigment produced by microorganisms, i.e., Serratia marcescens and other gram-negative bacteria. The anti-tumor potential of PG has been widely demonstrated. The families of PG (PGs), which share a common pyrrolylpyrromethene (PPM) skeleton, are produced by various bacteria. PGs are bioactive pigments and are known to exert immunosuppressive properties, in vitro apoptotic effects, and in vivo anti-tumor activities. Currently the most common strain used for producing PGs is S. marcescens. However, few reports have discussed PGs production. This review therefore describes the development of an anti-tumor drug, PG, that can be naturally produced by microorganisms, and evaluates the microbial production system, fermentation strategies, purification and identification processes. The application potential of PGs is also discussed.  相似文献   
8.
Polymethoxyflavones (PMFs) extracted from citrus peel exhibit potent anti-cancer activity, but are highly hydrophobic molecules with poor solubility in both water and oil at ambient and body temperature, which limits their bioavailability. The possibility of encapsulating PMFs within nanoemulsion-based delivery systems to facilitate their application in nutraceutical and pharmaceutical products was investigated. The influence of oil type (corn oil, MCT, orange oil), emulsifier type (β-lactoglobulin, lyso-lecithin, Tween, and DTAB), and neutral cosolvents (glycerol and ethanol) on the formation and stability of PMF-loaded nanoemulsions was examined. Nanoemulsions (r < 100 nm) could be formed using high pressure homogenization for all emulsifier types, except DTAB. Lipid droplet charge could be altered from highly cationic (DTAB), to near neutral (Tween), to highly anionic (β-lactoglobulin, lyso-lecithin) by varying emulsifier type. PMF crystals formed in all nanoemulsions after preparation, which had a tendency to sediment during storage. The size, morphology, and aggregation of PMF crystals depended on preparation method, emulsifier type, oil type, and cosolvent addition. These results have important implications for the development of delivery systems for bioactive components that have poor oil and water solubility at application temperatures.  相似文献   
9.
A simple and rapid multiresidue method for the determination of different veterinary drug residues in meat-based baby food (MBF) and powdered milk-based infant formulae (PMIF) has been developed. The method involves an extraction procedure based on buffered QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology, without any further clean-up step, followed by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method has been validated in two baby food matrices (MBF and PMIF) at three different concentration levels, obtaining suitable recoveries and precision (inter and intra-day precision) values. Quantification was carried out using matrix-matched standard calibration. Furthermore, the decision limit (CCα) and the decision capability (CCβ) were evaluated, ranging from 0.5 to 16.2 μg/kg and from 1.2 to 22.4 μg/kg, respectively. Finally, the method was applied to the analysis of several kinds of baby food samples and traces of some veterinary drugs were detected.  相似文献   
10.
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