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81.
蛋白质磷酸化修饰是一种重要的蛋白质翻译后修饰,在细胞代谢过程中发挥着重要作用。当蛋白质的正常磷酸化调节发生异常时,会导致癌症、糖尿病、心脏病等各种疾病的发生。因此,蛋白磷酸化分析对于疾病的早期快速诊断、药物筛选和治疗等方面具有重大的意义。由于蛋白质磷酸化过程是动态的,并且磷酸化肽段或蛋白在生物样品中的含量较低,因此高灵敏的蛋白磷酸化分析面临着巨大的挑战。该文依据在检测过程中,选择性识别或捕获磷酸化的肽段或蛋白的主要机理,综述了近几年纳米材料对磷酸化肽段的富集和信号放大作用在蛋白磷酸化分析中的研究进展,并对其未来研究方向进行了展望。  相似文献   
82.
复杂条件下潜在手印的发现及显现提取一直以来是刑事技术领域研究的热点和难点,尤其是潮湿或水中浸泡客体表面的潜在手印,往往因为环境条件的影响而无法使用常规的显现方法。因此,对于这类疑难条件下潜在手印的显现研究成为亟待解决的问题。本文分别对比了尼罗红、尼罗蓝、物理显影液三种可用于潮湿客体表面潜在手印显现的优化试剂,并对其可靠性、灵敏度及使用条件进行了详细的论证分析,为实战工作中疑难条件下潜在手印的显现提出了可靠的处理方法。  相似文献   
83.
Abstract

5-fluorouracil (5-FU) refers to a fluorinated pyrimidine analogue that has been widely used as an anticancer agent for colon, head, and neck cancers. Detection of 5-FU and its metabolites; 5-fluorouridine and 5-fluoro-2-deoxyuridine in biological samples allows optimization of pharmacotherapy and encourages fundamental investigations of this medication. The development of accurate and reliable sample preparation, as well as analytical methods, is critical to isolate targeted analytes from complex matrices, apart from increasing detection sensitivity of analytes. With that, this paper presents a review of prior studies pertaining to chromatographic and electrophoretic methods that focused on the analysis of 5-FU and its metabolites in biological matrices such as plasma and urine. This paper concentrates on HPLC, GC and CE systems, which are the most commonly used strategies for analytical separation of 5-FU and its metabolites from samples. Detection of these antineoplastic agents at trace level demands highly sensitive and selective analytical methodologies. Application of these analytical techniques to biological matrices is reviewed with a focus on method development strategies, including types of mobile phases and background electrolytes employed in LC and CE systems.  相似文献   
84.
[n.3.0]Bicycles (n = 3–6) can be synthesized using palladium-catalyzed asymmetric allylic alkylation followed by ruthenium-catalyzed cycloisomerization. New types of triarylphosphino-1,2-diaminooxazoline ligands show the same high levels of enantioselectivity observed with Trost ligand when employed in Pd-catalyzed allylic alkylation reactions. The enyne products of these allylic alkylation reactions were further elaborated using a Ru-catalyzed redox isomerization process, for which a mechanism is proposed.  相似文献   
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87.
Myotonic dystrophy (MyD) is a neuromuscular disease that is autosomal dominant and the most common form of muscular dystrophy affecting adults. The clinical features of MyD include a multisystemic disorder characterized by myotonia, progressive muscle weakness and wasting, cataracts, premature balding and mental retardation. The most severe type of MyD is classified as congenital MyD (CMyD). The muscle weakness in CMyD is very severe, but muscle development can be observed in the period of growth. However, no clinical case of this type has been reported yet. Therefore, we report on a girl with CMyD who had an increase in muscle strength over a four-year period. The girl with CMyD participated in this study from the age of 9 to the age of 12. The measurement of muscle strength was recorded as the maximum score of grip strength with the use of dynamometers. Grip strength was assessed once a year by the same two physical therapists. Grip strength of CMyD for each year was markedly weak when compared with the normal controls, but muscle strength changed within some specific growth areas. The muscle weakness in CMyD was remarkable, but the result showed that specific muscle strength of CMyD in childhood was actually increased.  相似文献   
88.
 Maintaining a high quality of research and development (R&D) is fundamental for the competitiveness of European industry. The development of new technologies and the improvement of existing technologies, products, production processes, measurement instrumentation and methods as well as basic research is essential. The objective of the workshop on "Quality Management in Analytical Chemical Research and Development" was to bring together experts from the academic world, industrial and institutional laboratories and also accreditation bodies to discuss the actual state of the art in the field of quality management in R&D, and to set up milestones for further activities. Furthermore, an important objective was to present the EURACHEM/CITAC Guide 2. The paper outlines the programme of the workshop and summarises the round-table discussions and expert recommendations. Most of the contributions to the round-table discussions will be published as full papers in a forthcoming issue of Accreditation and Quality Assurance. The workshop was organised by the Institut für Chemo- und Biosensorik (ICB), Münster, with the financial support of the SMT-Programme of the European Commission (Contract No.: SMT4-CT98-6534).  相似文献   
89.
水稻压致变异和高压对水稻生长发育的影响   总被引:13,自引:0,他引:13       下载免费PDF全文
 将高收获指数型优质籼稻(Oryza sativa L.)品种“粤香占”种子在不同条件下进行了3个生长周期的高压种子处理和实验室种植试验。稻种经高压处理后,与对照样品相比,当代种子发芽和秧苗成长较慢且植株个体差异较大;后期生长较快,分蘖数及产量与对照样持平或有所增加。受压样品产生了4种新的植株变异,其中2种为不育植株,另外两种变异植株种植至F2及F3代,变异性状都能稳定遗传。表明高压不仅可以对水稻当代植株生理产生明显的影响,而且可以诱导水稻产生明显和稳定的可遗传变异。  相似文献   
90.
In this research, the main purpose is to formulate a model to determine the optimum investment on port development from national investment prospective; on the other hand, costs and benefits are calculated from consumer and investor’s viewpoint. The formulated model is an integer-programming model. The emphasis is on how to formulate an investment optimization problem where cargo operation, investment costs, cargo-handling capacity, cargo transportation network, and the world maritime fleet constraints are included. Fuzzy numbers are used for cargo forecast study results. The output of the model is the type of design ships and design berths which are needed in each sub period, so that the port planner (the government) will find out the optimum development plan of port in each sub period when there is uncertainty in cargo handling forecast (fuzzy numbers).  相似文献   
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