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41.
S. S. Terekhov T. V. Bobik Yu. A. Mokrushina A. V. Stepanova N. M. Aleksandrova I. V. Smirnov A. A. Belogurov N. A. Ponomarenko A. G. Gabibov 《Applied Biochemistry and Microbiology》2016,52(2):162-169
A platform for the cloning and expression of active human butyrylcholinesterase (BuChE) in the yeast Pichia рastoris is first presented. Genetic constructs for BuChE gene expression, separately and in conjunction with a proline-rich peptide called proline-rich attachment domain (PRAD), are based on the vector pPICZαA. It is shown that the highest level of production is achieved in the expression of a BuChE gene without PRAD pPICZαA. It is found that one can obtain up to 125 mg of active enzyme from 1 L of culture medium at an optimal pH environment (pH 7.6), an optical seed culture density of 3 o.u., and an optimum methanol addition mode of (0.5% methanol in the first day and 0.2% thereafter from the second day). 相似文献
42.
The stratigraphic distribution and peculiarities of burial of caddis cases from 293 Mesozoic localities in Eurasia are analyzed. An attempt is made to analyze and interpret the co-occurrence of trichopteran cases and adults in the major localities. The main stages in the evolution of the building behavior of trichopteran larvae in the Mesozoic have been elucidated. 相似文献
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A new coptoclavid larva (Coleoptera: Adephaga: Dytiscoidea) from the Middle Jurassic of China,and its phylogenetic implication 总被引:2,自引:0,他引:2
Daohugounectes primitivus, a new genus and species of coptoclavid beetles, is described from 67 fossil larvae from the Jurassic locality of Daohugou,
northeastern China. It differs from other coptoclavids in the combination of the following characters: lateral lobes of nasale
present; legs relatively short, with tarsi flat and slightly dilated; abdominal tergite VIII almost circular; derivative of
abdominal segment IX present; urogomphi short; and helical thickening of tracheae weak. Most of these features are plesiomorphic
for the family Coptoclavidae and the superfamily Dytiscoidea. Among dytiscoids, a derivative of abdominal segment IX is present
only in the larvae of the recently discovered relic family Aspidytidae. 相似文献
45.
V. P. Shubin A. A. Ponomarenko A. S. Tsukanov O. A. Maynovskaya E. G. Rybakov M. V. Panina V. N. Kashnikov S. A. Frolov Yu. A. Shelygin 《Russian Journal of Genetics》2018,54(6):698-702
The expression profile of the ZEB1, ZEB2, VIM, CDH1, SFRP2, FOXQ1, TNC, MACC1, PLS3, CFTR, FLNA, MUC2, TFF3, and RARRES3 genes, as well as the mutational status of the KRAS, NRAS, BRAF, and PIK3CA genes, were investigated in 40 patients with colorectal cancer and liver metastases. A comparative analysis of changes in gene expression in primary tumor cells and liver metastases was performed. Statistically significant differences were found between the expression levels of the ZEB2 (p = 0.004), VIM (p < 0.001), FLNA (p = 0.04), and MUC2 (p < 0.001) genes. It was demonstrated that the overall frequency of mutations of the KRAS gene was 18/40 (45%) and the PIK3CA gene was 9/40 (23%). Mutations in the NRAS and BRAF genes were not found. The concordance between the primary tumor and metastases in the liver by mutation status was 100%. 相似文献
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FRANCESC SARDÀ‐PALOMERA GERARD BOTA CARLOS VIÑOLO ORIOL PALLARÉS VÍCTOR SAZATORNIL LLUÍS BROTONS SPARTACUS GOMÁRIZ FRANCESC SARDÀ 《Ibis》2012,154(1):177-183
Unmanned aircraft systems (UAS) are remote‐controlled devices capable of collecting information from difficult‐to‐access places while minimizing disturbance. Although UAS are increasingly used in many research disciplines, their application to wildlife research remains to be explored in depth. Here, we report on the use of a small UAS to monitor temporal changes in breeding population size in a Black‐headed Gull Chroicocephalus ridibundus colony. This method makes it possible to obtain georeferenced data on nest locations without causing colony disturbance, which would not otherwise be possible via direct ground observations. 相似文献
50.
Ponomarenko M. P. Rasskazov D. A. Chadaeva I. V. Sharypova E. B. Drachkova I. A. Ponomarenko P. M. Oshchepkova E. A. Savinkova L. K. Kolchanov N. A. 《Russian Journal of Genetics》2019,55(9):1137-1151
Russian Journal of Genetics - Atherosclerosis (AS) and AS-related pathologies such as coronary heart disease, myocardial infarction, angina pectoris, and stroke are the leading causes of death in... 相似文献