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排序方式: 共有750条查询结果,搜索用时 15 毫秒
731.
732.
A new sulphated heteropolysaccharide containing glucuronic acid, mannose, galactose, xylose, fucose and a protein moiety has been extracted from Sargassum linifolium. The polysaccharide extracted with HCl was richer in its carbohydrate and protein contents and contained lower amounts of ash than that extracted with oxalic acid. 相似文献
733.
Polyclonal activation of T and B lymphocytes by concanavalin A and lipopolysaccharide mitogens, respectively, was used to study the effect of iv injection of the following platinum compounds: cis-dichlorodiammine platinum, dichloro 1,2 benzenediamine N,N' platinum, cis-dichlorobis(cyclohexylamine) platinum, and cis-dichlorobis(cyclopentylamine) platinum, on murine T and B splenic lymphocytes. The results indicated that platinum compounds were more toxic to T-lymphocyte function than to B-lymphocyte function. These results were from both single-dose-time-course analysis and dose-response studies. 相似文献
734.
Elhendawy Mohammed Abdul-Baki Enas A. Abd-Elsalam Sherief Hagras Maha M. Zidan Abdul-Aziz Abdel-Naby Amira Y. Watany Mona Elkabash Ibrahem Ali Salem Mohamed Labib Elshanshoury Mohamed Soliman Shaimaa Abdou Said 《Molecular biology reports》2020,47(7):4955-4955
Molecular Biology Reports - The correct spelling of the 7th authors' name is Mona Watany. 相似文献
735.
Khalid M. Badr El-Din Hesham Salem Sayed Derayea Amany Abdelaziz Dalia M. Nagy 《Luminescence》2023,38(9):1583-1590
A spectrofluorimetric approach that is sensitive, simple, validated, and cost-effective has been proposed for the estimation of amlodipine (AML) and perindopril (PER) in their bulk powders, pharmaceutical formulations, and spiked human plasma. The recommended approach utilized the quantitative quenching effect of the two cited drugs on the fluorescence intensity of erythrosine B, as a result of complex binary reactions among each drug with erythrosine B at pH 3.5 (Teorell and Stenhagen buffer). The quenching of erythrosine B fluorescence was recorded at 554 nm after excitation at 527 nm. The calibration curve was detected in the range 0.25–3.0 μg ml−1, with a correlation coefficient of 0.9996 for AML, and 0.1–1.5 μg ml−1, with a correlation coefficient of 0.9996 for PER. The established spectrofluorimetric approach was validated for the estimation of the cited drugs with high sensitivity regarding International Council on Harmonization guidelines. Therefore, the established approach could be utilized for quality control of the cited drugs in their pharmaceutical formulations. 相似文献
736.
737.
738.
Karima Salem Fatma Elgharbi Hajer Ben Hlima Massimiliano Perduca Adel Sayari Aïda Hmida-Sayari 《Biotechnology progress》2020,36(4):e2964
An extracellular amylase (AmyKS) produced by a newly isolated Bacillus subtilis strain US572 was purified and characterized. AmyKS showed maximal activity at pH 6 and 60°C with a half-life of 10 min at 70°C. It is a Ca2+ independent enzyme and able to hydrolyze soluble starch into oligosaccharides consisting mainly of maltose and maltotriose. When compared to the studied α-amylases, AmyKS presents a high affinity toward soluble starch with a Km value of 0.252 mg ml−1. Coupled with the size-exclusion chromatography data, MALDI–TOF/MS analysis indicated that the purified amylase is a dimer with a molecular mass of 136,938.18 Da. It is an unusual feature of a non-maltogenic α-amylase. A 3D model and a dimeric model of AmyKS were generated showing the presence of an additional domain suspected to be involved in the dimerization process. This dimer arrangement could explain the high substrate affinity and catalytic efficiency of this enzyme. 相似文献
739.
740.
The acid-extractable, water-soluble, sulphated heteropolysaccharide, sargassan, contains residues of D-glucuronic acid, D-mannose, D-galactose, D-xylose, and L-fucose, and a protein moiety. Partial, acid hydrolysis of sargassan and auto-hydrolysis of the free-acid polysaccharide have been studied. Several acidic and neutral oligosaccharides were subsequently isolated. Evidence is advanced for the presence of ester sulphate on some galactose and fucose residues. It is concluded that the carbohydrate moiety of sargassan involves a backbone chain of D-glucuronic acid and D-mannose residues, and side chains involving residues of D-galactose, D-xylose, and L-fucose with sulphate attached to some galactose and fucose residues. 相似文献