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31.
V V Revin S A Kasatkin G N Cherkasova V T Nikolaev N S Iamashkina M N Chabushkina O A Popova V F Belianina 《Antibiotiki i khimioterapii͡a》1991,36(1):5-8
Influence of the quality of the fats used on their utilization in the process of cephalosporin C fermentation and accumulation was studied. A decrease in the level of all the fractions of the fatty acids was observed during the fermentation process. The antibiotic yield with the use of oxidized fats was lower. Treatment of the fats with gaseous nitrogen prevented their oxidation. It was supposed that the decreased yields of the antibiotic were associated with the influence of the oxidized fats on the biosynthetic processes. 相似文献
32.
L T Kushashvili A K Zhuravlev A G Borodkin G V Popova A D Nekliudov 《Antibiotiki i khimioterapii͡a》1988,33(1):16-22
The process of asymmetric deacylation of an acetyl derivative of 5-benzyl hydroxytryptophan racemate in the presence of native microbial aminoacylase was studied. The effect of pH, temperature, concentration of the enzyme and substrate were investigated. Conditions for preparation and isolation of individual amino acids were defined by optimization of N-Ac-DU-5-BOT hydrolysis. 相似文献
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V M Gagarinova E B Chepik E P Korneeva O M Litvinova T I Orlova N B Rumel' A K Golovanova M M Shvager T L Popova E A Smorodintseva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(12):34-37
In the summer of 1986 the epidemic, whose etiological agents were influenza viruses A (H1N1) and respiratory syncytial virus, was registered among the population of Novoshakhtinsk. In a number of mines 15.3-16.7% of the employees were affected. Influenza viruses A (H1N1) proved to be closely related in their antigenic and biological properties to viruses isolated in the USSR in March-June 1986, as well as to viruses A (H1N1), the etiological agents of the epidemic which developed in the USSR in October-December 1986. 相似文献
34.
Effects of delta sleep-inducing peptide on the intercentral integration during experimental epilepsy
N S Popova O S Adrianov R Veskov B Iankovich L Rakich 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(8):147-150
In free behavior experiments on cats it has been shown, that the intraperitoneal injection of delta-sleep-inducing peptide (100 mg/kg) may change organization of the pathology integration-epileptic discharges did not spread all the structures simultaneously. The slow-waves were registered in central medium of the thalamus and nucl. caudati. The epileptic discharges were registered first in visual and auditory cortex, hippocampus. After that they were observed in the motor cortex, nucl. caudati and centrum medianum of the thalamus. 相似文献
35.
ATP is an important modulator of gating in type 1 ryanodine receptor (RyR1), also known as a Ca2+ release channel in skeletal muscle cells. The activating effect of ATP on this channel is achieved by directly binding to one or more sites on the RyR1 protein. However, the number and location of these sites have yet to be determined. To identify the ATP-binding regions within RyR1 we used 2N3ATP-2′,3′-Biotin-LC-Hydrazone (BioATP-HDZ), a photo-reactive ATP analog to covalently label the channel. We found that BioATP-HDZ binds RyR1 specifically with an IC50 = 0.6±0.2 mM, comparable with the reported EC50 for activation of RyR1 with ATP. Controlled proteolysis of labeled RyR1 followed by sequence analysis revealed three fragments with apparent molecular masses of 95, 45 and 70 kDa that were crosslinked by BioATP-HDZ and identified as RyR1 sequences. Our analysis identified four glycine-rich consensus motifs that can potentially constitute ATP-binding sites and are located within the N-terminal 95-kDa fragment. These putative nucleotide-binding sequences include amino acids 699–704, 701–706, 1081–1084 and 1195–1200, which are conserved among the three RyR isoforms. Located next to the N-terminal disease hotspot region in RyR1, these sequences may communicate the effects of ATP-binding to channel function by tuning conformational motions within the neighboring cytoplasmic regulatory domains. Two other labeled fragments lack ATP-binding consensus motifs and may form non-canonical ATP-binding sites. Based on domain topology in the 3D structure of RyR1 it is also conceivable that the identified ATP-binding regions, despite their wide separation in the primary sequence, may actually constitute the same non-contiguous ATP-binding pocket within the channel tetramer. 相似文献
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I. V. Sorokina I. Ya. Mainagashev N. A. Zhukova D. V. Korchagina T. G. Tolstikova V. P. Nikolin N. A. Popova M. A. Pokrovskii A. G. Pokrovskii N. F. Salakhutdinov 《Russian Journal of Bioorganic Chemistry》2013,39(2):194-201
Amides containing homopiperidine and piperazine cycles were synthesized from dihydrobetulonic acid obtained by the oxidation of dihydrobetulin. All substances were shown to have a high antitumor activity (CCID50 = 3.5–36.2 μM) in vitro in lymphoid (CEM-13, U-937) and monocytic (MT-4) human cell lines. Amides containing the methyl- and ethylpiperazine residues do not influence the viability of Lung Lewis Carcinoma cells in culture and do not have a significant effect on its transplants in C57BL/6 mice. However, these amides efficiently inhibit the development of metastases in lungs of these mice. The antimetastatic activity of the studied amides increases with changing the methyl by ethyl aliphatic residue in the piperazine cycle. 相似文献
40.
Antonia P. Popova 《Journal of cell communication and signaling》2013,7(2):119-127
Bronchopulmonary dysplasia (BPD) is a chronic lung disease affecting premature infants with long term effect on lung function into adulthood. Multiple factors are involved in the development of BPD. This review will summarize the different mechanisms leading to this disease and highlight recent bench and clinical research targeted at understanding the role of the mesenchyme (both its cellular and extracellular components) in the pathogenesis of BPD. 相似文献