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281.
A. V. Khromov V. A. Gushchin V. I. Timerbaev N. O. Kalinina M. E. Taliansky V. V. Makarov 《Doklady. Biochemistry and biophysics》2018,479(1):90-94
The activity of the pool of sgRNA molecules designed for different regions of potato coilin and phytoene desaturase genes was compared in vitro. Due to the presence of nucleotides unpaired with DNA, sgRNA is able not only to inhibit but also to stimulate the activity of the Cas9–sgRNA complex in vitro. Although the first six nucleotides located in the DNA substrate proximally to the PAM site at the 3' end are the binding sites for cas9, they had no significant effect on the activity of the Cas9–sgRNA complex. 相似文献
282.
Pikunova A. V. Knyazev S. D. Golyaeva O. D. Bahotskaya A. U. Kalinina O. V. 《Russian Journal of Genetics》2019,55(9):1061-1071
Russian Journal of Genetics - The paper provides an overview of foreign and Russian studies of the genus Ribes genome by means of DNA markers. A list of methods for DNA extraction from currants is... 相似文献
283.
CHRISTOPHER R. TRACY KEITH A. CHRISTIAN NICOLE BURNIP BEAU J. AUSTIN ALYSSA CORNALL SEBASTIAN IGLESIAS STEPHEN J. REYNOLDS THOMAS TIXIER CAMILLE LE NOËNE 《Austral ecology》2013,38(4):476-483
Amphibians are typically intolerant of high temperatures and dehydrating conditions, and small species are particularly susceptible to desiccation. The rockhole frog, Litoria meiriana (Hylidae), is diurnal and is often observed on rocks in the sun near streams in tropical Australia. These hot, desiccating conditions are avoided by most frog species. We measured the microclimate in the areas used by frogs and the activity, body temperatures and hydric state of free‐ranging individuals of this small frog. We also used plaster models to further explore the dynamic nature of hydric state by combining estimates of water loss and water uptake with behavioural observations of activity and microhabitat selection. Both direct measures and estimates of dynamic hydric state indicated that free‐ranging frogs generally maintained a hydric state above 95% of full hydration, but occasionally, particularly during the afternoon, frogs allowed their hydric state to fall as low as 85%. Body temperatures of frogs remained below the critical thermal maximum (CTmax) even when the frogs were in the sun, because this species has no cutaneous resistance to evaporative water loss and so they cool by evaporation. However, during the hotter part of the day, on dry sunny substrates, the hydric state of the frogs could fall to near lethal hydration states (approximately 70% of full hydration) within a short period (approximately 20 min). Thus, the threat of desiccation appears to be more limiting than the threat of overheating. These diurnal frogs rely on frequent bouts of rehydration to support their ability to venture onto hot, dry rocks during the day. 相似文献
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D. S. Kalinina A. B. Vol’nova O. S. Alekseeva I. A. Zhuravin 《Journal of Evolutionary Biochemistry and Physiology》2016,52(5):352-358
Changes in electrical activity of the neocortex after prenatal hypoxia (day 14 of embryogenesis, E14, 7% O2 for 3 h) and intracortical microinjection of epileptogenic 4-aminopyridine (4-AP) were studied in adult (3-month-old) rats. The frequency–time parameters of electrocorticogram (ECoG) were analyzed during sleep and wakefulness as well as in a model of 4-AP-induced spike-wave discharge (SWD) epileptiform activity. The results showed that in rats exposed to prenatal hypoxia the theta rhythm had a lower frequency while sleep spindles displayed a lower spectral power in the low-frequency range as compared to the control group. In rats with prenatal pathology, there was revealed a delayed onset of epileptiform activity and a shifted frequency distribution of the SWD spectral power induced by 4-AP. 相似文献
286.
A micropropagation approach was developed for nine ornamental Prunus species, P. americana, P. cistena, P. glandulosa, P. serrulata ‘Kwanzan’, P. laurocerasus, P. sargentii, P. tomentosa, P. triloba, P. virginiana ‘Schubert’, commercially important in North America, and GF305 peach, commonly used for Prunus virus indexing. The micropropagation cycle based on proliferation of vegetative tissues includes establishment of tissue
culture through introduction of shoot meristems in vitro, shoot proliferation, root induction and plant acclimatization steps
and can be completed in 5 months. A meristem sterilization protocol minimized bacterial and fungal contamination. Multiple
shoot formation in ornamental Prunus was obtained through the use of 1 mg l−1 6-benzyladenine. For GF305 peach, alteration in the sugar composition, fructose instead of sucrose, and addition of 1 mg l−1 ferulic acid had a significant impact on the shoot proliferation rate and maintenance of long-term in vitro culture. Rooting
and plant acclimatization conditions were improved using a two-step protocol with a 4-day root induction in indole-3-butiric
acid (IBA)-containing media with consequent 3-week root elongation in IBA-free media. One-month incubation of rooted shoots
in a vermiculite-based medium resulted in additional shoot and root growth and provided better acclimatization and plant recovery.
The micropropagation approach can be used for maintenance of the clonal properties for Prunus spp. as well as a protocol to support meristem therapy against viral infection. 相似文献
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T E Kalinina 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1976,26(2):333-342
Elaboration and manifestation of motor alimentary conditioned reflexes were studied after a lesion of medial geniculate bodies (MGB) in adult cats. No substantial disturbance were recorded of the capacity for pitch analysis. In the case of more extensive MGB lesions, there were some difficulties in the elaboration of tone differentiations but not in their achievement. Additional temporo-parietal cortical ablation drastically reduced the animals' capacity for anlysing sound frequencies and more profoundly disturbed their capacity for inhibitory reactions. 相似文献
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