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11.
The effective synthesis of 4,4,14α-trimethyl-19 (10 → 9β) abeo-steroids (iv), (v), and (Vl) with two- and five-carbon side chains from lanosterol is described. Their structures were proved on the basis of spectral data. The title compounds are the first synthetic synthons for the preparation of 4,4,14α-trimethyl-steroids with an unnatural configuration. 相似文献
12.
A simple filter method for the fluorometric estimation of DNA in alkaline and neutral sucrose gradient fractions with DABA·2HCl is discussed. Alpha-450 membrane filters of regenerated cellulose (Gelman Instrument Co., Ann Arbor, Michigan) were used. In the proposed method washing of the DNA precipitate as well as the reaction with DABA·2HCl were performed directly on the filters, thus avoiding repeated washing and centrifugations of DNA precipitates applied hitherto in analogous fluorometric techniques. A good coincidence of the results concerning localization of DNA sedimentation profiles determined by radioisotopic and fluorometric methods was obtained. The method is very convenient for DNA estimation in alkaline and neutral sucrose density gradient fractions obtained by ultracentrifugation of DNA of nonproliferating cells where DNA labeling is very difficult, and in the case of human lymphocytes even impossible without stimulation for blastic transformation. Its other advantages are a considerably simplified procedure and a higher precision with respect to other fluorometric methods for determination of DNA. 相似文献
13.
Summary Normal mouse spleen cells take up in vitro radioactively labeled immune RNA. RNA taken up is present in nuclei, polysomes, membranes and cytoplasm. About 20–40% of immune RNA is nonspecifically associated with cell surface. 45% of RNA taken up is degraded and reutilized inside the cells within 2 hours.This work was supported by the Polish Academy of Sciences within the project 09.7.4.1.1. 相似文献
14.
Protha Biswas Uttpal Anand Suchismita Chatterjee Saha Nishi Kant Tulika Mishra Harison Masih Ananya Bar Devendra Kumar Pandey Niraj
Kumar Jha Madhumita Majumder Neela Das Vijaykumar
Shivaji Gadekar Mahipal S. Shekhawat Manoj Kumar Radha Jarosaw Prokw Jos M. Prez de la Lastra Abhijit Dey 《Journal of cellular and molecular medicine》2022,26(11):3083
15.
Genetic analysis of Curvularia lunata IM 2901 transformants, previously obtained by electroporation with plasmid pAN7-1, was carried out. Isolates displayed several differences in hygromycin B resistance and their physiology. It was shown that plasmid pAN7-1 was integrated in different copy numbers and at different positions in the genome of the strains studied. Both the wild type and pAN7-1 isolates, when growing in liquid media, produced an extracellular emulsifying agent. The transformants differed in their growth kinetics, intensity of surfactant production and in the efficiency of cortexolone 11beta-hydroxylation, in comparison with the wild type. The micro-organisms varied in susceptibility to the lytic enzyme complex (Novozyme 234), which indicated the presence of differences in their cell wall composition and/or in architecture caused by an integrated plasmid pAN7-1. 相似文献
16.
Biotransformation of 4‐fluoro‐N‐(1‐{2‐[(propan‐2‐yl)phenoxy]ethyl}‐8‐azabicyclo[3.2.1]octan‐3‐yl)‐benzenesulfonamide,a novel potent 5‐HT7 receptor antagonist with antidepressant‐like and anxiolytic properties: In vitro and in silico approach 下载免费PDF全文
Karolina Słoczyńska Katarzyna Wójcik‐Pszczoła Vittorio Canale Paweł Żmudzki Paweł Zajdel Elżbieta Pękala 《Journal of biochemical and molecular toxicology》2018,32(5)
The aim of the study was to investigate the metabolism of 4‐fluoro‐N‐(1‐{2‐[(propan‐2‐yl)phenoxy]ethyl}‐8‐azabicyclo[3.2.1]octan‐3‐yl)‐benzenesulfonamide (PZ‐1150), a novel 5‐HT7 receptor antagonist with antidepressant‐like and anxiolytic properties, by the following three ways: in vitro with microsomes; in vitro employing Cunninghamella echinulata, and in silico using MetaSite. Biotransformation of PZ‐1150 with microsomes resulted in five metabolites, while transformation with C. echinulata afforded two metabolites. In both models, the predominant metabolite occurred due to hydroxylation of benzene ring. In silico data coincide with in vitro experiments, as three MetaSite metabolites matched compounds identified in microsomal samples. In human liver microsomes PZ‐1150 exhibited in vitro half‐life of 64 min, with microsomal intrinsic clearance of 54.1 μL/min/mg and intrinsic clearance of 48.7 mL/min/kg. Therefore, PZ‐1150 is predicted to be a high‐clearance agent. The study demonstrated the applicability of using microsomal model coupled with microbial model to elucidate the metabolic pathways of compounds and comparison with in silico metabolite predictions. 相似文献
17.
Szoszkiewicz Krzysztof Jusik Szymon Lewin Iga Czerniawska-Kusza Izabela Kupiec Jerzy Mirosław Szostak Marta 《Hydrobiologia》2018,808(1):327-342
Hydrobiologia - The aim of the study was to compare the patterns of development of macrophytes and macroinvertebrates in different types of reference mountain rivers. The study is based on... 相似文献
18.
Hanna Grajek Regina Drabent Grażyna Żurkowska Czesław Bojarski 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,801(3):456-460
The electronic absorption spectra of the flavomononucleotide (FMN) in aqueous solution and in glycerine-water solution with change of the dye concentration have been measured. The FMN dimer absorption spectrum, monomer absorption spectrum, dimerization constant K and molar fraction of the monomer were calculated. It was found that FMN dimerization constants in aqueous solution were Ka = 118.0 l/mol and in glycerine Kg = 20.5 l/mol. In the region of the monomer absorption band two dimer absorption bands appear, in accordance with the Kasha molecular exciton theory. 相似文献
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20.
Bączyk Justyna Gogiel Tomasz Wolańska Małgorzata Bruczko Marta Guszczyn Tomasz Popko Janusz Romanowicz Lech 《International journal of peptide research and therapeutics》2020,26(1):271-280
International Journal of Peptide Research and Therapeutics - The progressive damage of human articular cartilage is associated with loss of integrity of its extracellular matrix components. Their... 相似文献