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31.
Permineralised wood of Eristophyton sp. is first described from the Carboniferous deposits of the Arkhangelsk region, northern Russia. The specimens used in the study show scalariform thickening of the metaxylem tracheids both on radial and tangential walls. Eristophyton sp. indicates well preserved elements of secondary xylem: uni-, rarely biseriate xylem rays up to 15–16 cells high; uni-, multiseriate tracheid pitting only on radial walls; 1–8 contiguous cross-field pits and their inclined narrow apertures. A brief review and comparison with known anatomically preserved plants from the Lower Carboniferous of different localities of Scotland, France, USA and Poland is discussed.  相似文献   
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Ectoparasites of bats in the Neotropics are diverse and play numerous ecological roles as vectors of microbial pathogens and endoparasites and as food sources for other cave fauna living both on their hosts and in bat roosts. The ectoparasites of bats in Jalisco State of western Mexico have not been as well described as those of other states with recent checklists that have focused primarily on the Yucatan Peninsula. We captured bats from 2011–2015 on the south coast and Sierra de Amula, Jalisco using mist nets, and we removed ectoparasites by hand. We identified 24 species of streblid bat flies and six ectoparasitic mites from bats caught in mist nets. There were an additional eight possibly undescribed species of Streblidae. Our collections extend the known range of species into Jalisco.  相似文献   
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Both leptin and ghrelin used separately at the concentrations corresponding to trimesters II–III of pregnancy increase the number of CD56bright NK cells in mononuclear cell suspension; their combination also enhances the L-selectin expression on the surface of these cells in the culture. These hormones do not affect the production of TGF-β1, IL-17А, or IFN-γ by NK cells, and they inhibit the production of IL-10. Leptin decreses the IL-4 production by NKp46+ cells, but the presence of ghrelin abrogates this effect.  相似文献   
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The desC gene for the acyl-lipid Delta9-desaturase from the thermophilic cyanobacterium Synechococcus vulcanus was introduced into Nicotiana tabacum under control of the 35S promoter. Expression of the desaturase was confirmed by Western blotting. Lipid analysis revealed that lipid content and the extent of fatty acid unsaturation significantly increased in leaves of transgenic plants. Chilling tolerance of those plants also increased, as estimated by the electrolyte leakage from the tissues damaged by cold treatments. Seeds of plants that expressed the desC gene imbibed at low temperatures demonstrated higher chilling tolerance than those of the control plants. The results demonstrate that the cyanobacterial thermophilic acyl-lipid desaturase was efficiently expressed in tobacco at ambient temperatures, and its expression resulted in the enhanced chilling tolerance of the transgenic plants.  相似文献   
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Petrukhin  O. V.  Orlova  T. G.  Nezvetsky  A. R.  Orlov  N. Ya. 《Biophysics》2019,64(5):694-695
Biophysics - Abstract—It has been previously shown in the study of the kinetic behavior of cGMP-specific phosphodiesterase in preparations of the outer segments of bovine retinal rods, which...  相似文献   
37.
During tumor invasion, benign myoepithelial cells of carcinoma ex-pleomorphic adenoma (CXPA) surround malignant epithelial cells and disappear. The mechanisms involved in the death and disappearance of these myoepithelial cells were investigated via analysis of the expression of regulatory proteins for apoptosis, autophagy and cellular senescence in an in situ in vitro model. Protein expression relating to apoptosis (Bax, Bcl-2, Survivin), autophagy (Beclin-1, LC3B) and cellular senescence (p21, p16) was evaluated using indirect immunofluorescence. β-galactosidase expression was assessed via histochemistry. Biopsies of CXPA (ex vivo) allowed immunhistochemical evaluation of p21 and p16, whilst LC3B, p21 and p16 protein expression was analyzed by western blotting. In the in vitro model, the myoepithelial cells were positive for LC3B (cytoplasm) and p21 (nucleus), whilst in vivo positivity for p21 and p16 was observed. In vitro, β-galactosidase activity increased in the myoepithelial cells over time. Western blotting analysis revealed an increased LC3B, p16 and p21 expression in the myoepithelial cells with previous contact with the malignant cells when compared with those without contact. The investigation of behavior of benign myoepithelial cells in ductal areas of CXAP revealed that the myoepithelial cells are involved in the autophagy-senescence phenotype that subsequently leads to their disappearance.  相似文献   
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An optical averaging of rat liver ribosome small subunit images revealed seven strands with a mean diameter of about 50 Å. A tentative model of the 3D arrangement of the strands is suggested. An assumption is made that these strands are clusters of protein molecules arranged on the double-helical regions of RNA.  相似文献   
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