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721.
Pavel V Mazin Mikhail S Gelfand Andrey A Mironov Aleksandra B Rakhmaninova Anatoly R Rubinov Robert B Russell Olga V Kalinina 《Algorithms for molecular biology : AMB》2010,5(1):29
Background
Recent progress in sequencing and 3 D structure determination techniques stimulated development of approaches aimed at more precise annotation of proteins, that is, prediction of exact specificity to a ligand or, more broadly, to a binding partner of any kind. 相似文献722.
723.
Ludmila P. Ponomarenko Anatoly I. Kalinovsky Ekaterina A. Martyyas Roman V. Doudkin Petr G. Gorovoy Valentin A. Stonik 《Phytochemistry letters》2012,5(1):118-122
Six naturally occurring terpenoids were isolated from the hexane extract of rabbit-head wormwood Artemisia lagocephala (Fisch. ex Besser) DC. The terpenoids’ structures were elucidated by spectroscopic and chemical methods as 3β-acetoxycycloartan-24-ozonide (1), 3β-acetoxycycloartan-24-al (2), 25,26,27-trisnor-3β-acetoxycycloartan-24-ol (3), 24,25,26,27-tetranor-3β-acetoxycycloartan-23-ol (4), and the previously known caryophyllene oxide (5) and (1R,4S)-p-menth-2-en-1-ol (6). 相似文献
724.
Boris A. Dmitriev Anatoly Ya. Chernyak Oleg S. Chizhov Nikolay K. Kochetkov 《Carbohydrate research》1976,47(1):25-34
Acid-catalyzed acetonation of d-glycero-d-galacto-heptose yields solely the 1,2:3,4:6,7-tri-O-isopropylidene pyranoid derivative, whereas d-glycero-l-gluco- and d-glycero-l-manno-heptose react in the furanose form to give 1,2:5,6-(major) and 1,2:6,7-di-O-isopropylidene-d-glycero-l-gluco-heptose (minor), and 2,3:5,6-(major) and 2,3:6,7-di-O-isopropylidene-d-glycero-l-manno-heptose (minor), respectively. 相似文献
725.
Anatoly A. Gitelson Supat Laorawat Galya P. Keydan Avigad Vonshak 《Journal of phycology》1995,31(5):828-834
Reflectance and vertical attenuation coefficient spectra from 400 to 1100 nm were investigated in detail on dense algal cultures of Spirulina in order to create algorithms for remote estimation of pigment and biomass concentration. Reflectance and the vertical attenuation coefficients were compared with biomass and pigment concentration in outdoor algal cultures. For assessing biomass concentration, the sum of reflectance above the base line from 670 to 950 nm was used. This allows the estimation of biomass with an error of less than 0.06 g·L?1 For chlorophyll a and phycocyanin estimation, vertical attenuation coefficients at the wavelengths 440 nm (or 676 nm) and 624 nm, respectively, were employed. The developed algorithms were tested by using independent data sets in the range of chlorophyll a from 0.2 to 20mg·L?1 and biomass from 0.15 to 1.1 g·L?1. An error of pigment estimation of less than 0.80 mg·L?1 was achieved. The potential use of the algorithms in algal biotechnology is further discussed. 相似文献
726.
Addition of chloroazide to 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-d-lyxo- (1) and -d-arabino-hex-1-enitol (2) under u.v. irradiation proceeds regio- and stereo-selectively yielding mainly O-acetyl derivatives of 2-azido-2-deoxy-d-galactopyranose and -d-glucopyranose, respectively. 3,4,6-Tri-O-acetyl-2-chloro-2-deoxy-α-d-galactopyranosyl azide and 3,4,6-tri-O-acetyl-2-azido-2-deoxy-α-d-talopyranose (from 1), and 1,3,4,6-tetra-O-acetyl-2-chloro-2-deoxy-α-d-glucopyranosyl azide and 1,3,4,6-tetra-O-acetyl-2-azido-2-deoxy-α-d-mannopyranose (from 2) are byproducts. 1,5-Anhydro-3,4,6-tri-O-benzyl-2-deoxy-d-lyxo- and -d-arabino-hex-1-enitol reacted more rapidly with chloroazide, to give, under irradiation, derivatives of 2-azido-2-deoxy-d-galactose and -d-glucose, respectively. However, reaction in the dark gave mainly O-benzyl derivatives of 2-chloro-2-deoxy-α-d-galacto- and -α-d-glucopyranosyl azide. The difference between the products obtained may depend on the existence of two parallel processes, one radical (under irradiation), and the other ionic (reaction in the dark). 相似文献
727.
Timofey V. Malyarenko Alla A. Kicha Natalia V. Ivanchina Anatoly I. Kalinovsky Pavel S. Dmitrenok Svetlana P. Ermakova Valentin A. Stonik 《Steroids》2011,76(12):1280-1287
Six new steroidal biglycosides, cariniferosides A–F (1–6), were isolated along with six previously known glycosides, 7–12, from the alcoholic extract of the starfish Asteropsis carinifera. The structures of 1–6 were determined by extensive NMR and ESIMS techniques. The isolated compounds did not show any apparent cytotoxicity in cancer cell lines HCT-116, RPMI-7951, and T-47D, but sulfated compounds 6, 11, and 12 demonstrated a significant inhibition of RPMI-7951 and T-47D cell colony formation in a soft agar clonogenic assay. 相似文献
728.
Peter Strizhak Igor S. Magura Konstantin B. Yatsimirskii Anatoly I. Masyuk 《Journal of biological physics》1995,21(4):233-239
A modified method of the return map reconstruction is proposed. The method is applied to the analysis of intracellular calcium oscillations. On the basis of the approach developed, these oscillations are recognized as low-dimensional deterministic chaotic process. 相似文献