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991.
依据丙型肝炎病毒(HCV)多蛋白核心区N端氨基酸序列和密码子简并性,人为设计并采用半化学半酶促的方法合成了一个DNA片段。经核酸杂交检测以及DNA序列分析证实,该片段的核苷酸序列与设计完全一致。将合成的DNA片段插入融合表达载体pGEX-2T中,表达产物经亲和层析纯化后进行Western免疫印迹实验和间接ELISA分析,结果表明,融合蛋白具有HCV核心区抗原的免疫反应性,可望用于HCV抗体的检测.此外,编码HCV优势抗原表位的化学合成基因有可能为HCV嵌合抗原的研究提供一条捷径。 相似文献
992.
993.
Francisco J. L. Aragao Maria F. Grossi de Sa Eleonora R. Almeida Eugen S. Gander Elibio L. Rech 《Plant molecular biology》1992,20(2):357-359
Bean (Phaseolus vulgaris L.) mature embryos were transformed using biolistic methods with a plasmid containing 2S albumin and -glucuronidase structural sequences, both under the control of the 35S CaMV promoter. We have shown that chimaeric tissues could be obtained and that both structural sequences were expressed to similar levels. 相似文献
994.
Seminal liquefaction corresponds to a proteolysis of glycoproteins and could also result in a lysis of linked glycans involving glycosidases. It is well known that α-1-4 glucosidase is a real epipidymal marker. The aim of this study is to point out new markers among the glycosidases and especially β-D-mannosidase, α-L-fucosidase and N-acetyl-β-D-glucosaminidase. There is no correlation between the three enzymatic activities and the sperm count. Moreover in case of azoospermia enzymatic activities were always present. The variations observed are both quantitative (β-MAN activity is significantly decreased) and qualitative (modifications of the relative proportions of the different enzymatic forms) according to the etiology of azoospermia. 相似文献
995.
996.
Rajaa Boulahjar Angela Rincon Arias Raphaël Bolteau Nicolas Renault Mathilde Coevoet Amélie Barczyk Romain Duroux Saïd Yous Patricia Melnyk Laurence Agouridas 《Bioorganic & medicinal chemistry》2018,26(12):3296-3307
Imidazo[1,2a]pyridines have gained much interest in the field of medicinal chemistry research. In the aim of accessing new privileged structure, we decided to design and synthesize 8-aminated-imidazo[1,2a]pyridines substituted on positions 2 and 6. This scaffold, rarely found in the literature, was obtained via palladium-catalyzed coupling reactions (Suzuki reaction or N-hydroxysuccinimidyl activated ester method) and tested on adenosine receptor A2A. We demonstrated how incorporation of an exocyclic amine enhanced affinity towards this receptor while maintaining low cytotoxicity. 相似文献
997.
998.
Jingwen Feng Tong Feng Chengwen Yang Wei Wang Yu Sa Yuanming Feng 《Apoptosis : an international journal on programmed cell death》2018,23(5-6):290-298
This study was to explore the feasibility of prediction and classification of cells in different stages of apoptosis with a stain-free method based on diffraction images and supervised machine learning. Apoptosis was induced in human chronic myelogenous leukemia K562 cells by cis-platinum (DDP). A newly developed technique of polarization diffraction imaging flow cytometry (p-DIFC) was performed to acquire diffraction images of the cells in three different statuses (viable, early apoptotic and late apoptotic/necrotic) after cell separation through fluorescence activated cell sorting with Annexin V-PE and SYTOX® Green double staining. The texture features of the diffraction images were extracted with in-house software based on the Gray-level co-occurrence matrix algorithm to generate datasets for cell classification with supervised machine learning method. Therefore, this new method has been verified in hydrogen peroxide induced apoptosis model of HL-60. Results show that accuracy of higher than 90% was achieved respectively in independent test datasets from each cell type based on logistic regression with ridge estimators, which indicated that p-DIFC system has a great potential in predicting and classifying cells in different stages of apoptosis. 相似文献
999.
1000.