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161.
Dominance relations and the pituitary-adrenal system in rats 总被引:1,自引:0,他引:1
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Popov SV Vinter VG Patova OA Markov PA Nikitina IR Ovodova RG Popova GY Shashkov AS Ovodov YS 《Biochemistry. Biokhimii?a》2007,72(7):778-784
The pectic polysaccharide named rauvolfian RS was obtained from the dried callus of Rauvolfia serpentina L. by extraction with 0.7% aqueous ammonium oxalate. Crude rauvolfian RS was purified using membrane ultrafiltration to yield
the purified rauvolfian RSP in addition to glucan as admixture from the callus, with molecular weights 300 and 100–300 kD,
respectively. A peroral pretreatment of mice with the crude and purified samples of rauvolfian (RS and RSP) was found to decrease
colonic macroscopic scores, the total area of damage, and tissue myelope roxidase activity in colons as compared with a colitis
group. RS and RSP were shown to stimulate production of mucus by colons of the colitis mice. RSP appeared to be an active
constituent of the parent RS. The glucan failed to possess anti-inflammatory activity.
Published in Russian in Biokhimiya, 2007, Vol. 72, No. 7, pp. 955–962. 相似文献
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166.
Transcriptome‐based phylogeny of endemic Lake Baikal amphipod species flock: fast speciation accompanied by frequent episodes of positive selection
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167.
Tatiana V. Ilchibaeva Anton S. Tsybko Rimma V. Kozhemyakina Maria Y. Konoshenko Nina K. Popova Vladimir S. Naumenko 《Journal of Ethology》2017,35(1):75-81
Aggressive behavior is not a unitary trait, and different stimuli/situations elicit different kinds of aggressive behavior. According to numerous data the genotype plays a significant role in the expression of aggressive behavior. However, it remains unclear how genetic predisposition to one kind of aggression is linked with other kinds of aggressive behavior, especially pathological aggression (infanticide). Here, we report on our investigation of the expression of defensive, offensive, predatory and asocial aggression in wild rats selectively bred for 85 generations for either a high level or a lack of aggression towards humans. We found that those rats genetically predisposed to a high level of defensive aggression showed decreased social behavior and increased pathological aggressive behavior towards juvenile males. The highly aggressive rates showed a reduced latency time of attack and an increased latency time of the first social contact. Rats genetically predisposed to defensive aggression demonstrated increased predatory aggression—latency time of muricide was shorter in highly aggressive than in tame animals. At the same time, both lines of rats did not differ significantly in intermale aggression. We conclude that the data indicate a close relation between defensive, predatory and pathological aggressive behavior that allows us to suggest that similar genetic mechanisms underlie these types of aggressive behavior. 相似文献
168.
S. S. Popova I. M. Vikhlyantsev N. M. Zakharova Z. A. Podlubnaya E. E. Fesenko 《Doklady. Biochemistry and biophysics》2017,472(1):56-59
Seasonal changes in proteolytic activity and content of calpains in striated muscles of the longtailed ground squirrel Spermophilus undulatus were studied by casein zymography and Western blotting analysis. The results testify to hyperactivation of calpain proteases in the skeletal muscles of awakened animals during the “winter” activity. The observed changes are discussed in the context of adaptation of skeletal muscles of long-tailed ground squirrels to hibernation. 相似文献
169.
O. B. Popova N. M. Sanina G. N. Likhatskaya I. P. Bezverbnaya 《Russian Journal of Marine Biology》2008,34(3):179-185
The phospholipid and fatty acid composition and thermotropic behavior of total lipids were studied in the metal-accumulating marine strain Pseudomonas putida IB28 grown in the presence of Cu2+ and Cd2+ at 4 and 24°C. Despite the changes in acidic lipid content, unsaturated/saturated fatty acid ratio, and cyclopropane fatty acid level, the temperature range of calorimetric phase transitions of bacterial total lipids was slightly altered under these factors. The suppressive action of heavy metals on bacterial growth is attributable to the phase separation of lipids and, as a consequence, to a sharp increase in the ion permeability of the lipid bilayer. The increase in acidic phospholipid level under the influence of Cu2+ and Cd2+, especially at 24°C, is likely to be indicative of their complexation with heavy metal ions. 相似文献
170.
Thevelein JM Bonini BM Castermans D Haesendonckx S Kriel J Louwet W Thayumanavan P Popova Y Rubio-Texeira M Schepers W Vandormael P Van Zeebroeck G Verhaert P Versele M Voordeckers K 《Acta microbiologica et immunologica Hungarica》2008,55(2):75-89
In yeast the Protein Kinase A (PKA) pathway can be activated by a variety of nutrients. Fermentable sugars, like glucose and sucrose, trigger a spike in the cAMP level, followed by activation of PKA and phosphorylation of target proteins causing a.o. mobilization of reserve carbohydrates, repression of stress-related genes and induction of growth-related genes. Glucose and sucrose are sensed by a G-protein coupled receptor system that activates adenylate cyclase and also activates a bypass pathway causing direct activation of PKA. Addition of other essential nutrients, like nitrogen sources or phosphate, to glucose-repressed nitrogen- or phosphate-starved cells, also triggers rapid activation of the PKA pathway. In these cases cAMP is not involved as a second messenger. Amino acids are sensed by the Gap1 transceptor, previously considered only as an amino acid transporter. Recent results indicate that the amino acid ligand has to induce a specific conformational change for signaling. The same amino acid binding site is involved in transport and signaling. Similar results have been obtained for Pho84 which acts as a transceptor for phosphate activation of the PKA pathway. Ammonium activation of the PKA pathway in nitrogen-starved cells is mediated mainly by the Mep2 transceptor, which belongs to a different class of transporter proteins. Hence, different types of sensing systems are involved in control of the yeast PKA pathway by nutrients. 相似文献