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141.
The timing of vertical migration in planktonic foraminifera (ex. ontogenetic, diel) is still an open debate. This work aims to investigate the diel vertical migration (DVM) of Neogloboquadrina pachyderma (N. pachyderma) and Turborotalita quinqueloba (T. quinqueloba) in the Arctic during the midnight sun. N. pachyderma and T. quinqueloba dominate the total assemblage in the cold Polar Water and warmer North Atlantic Water masses, respectively. Foraminifera were collected at several depths along the Fram Strait. Afterwards sampling was performed at the same station for 24 h at continuous and discrete time intervals. Results show no evidence of planktonic foraminifera DVM since there was no significant variability in the abundance and size distribution during the 24-h collection period. This finding provides information to improve the interpretation of foraminifera in paleoclimatic works. This is especially relevant in the Fram Strait as paleoclimatic studies in this region are fundamental to investigating the history of the Atlantic water inflow into the Arctic Ocean. 相似文献
142.
Mitochondrial dysfunction in a transgenic mouse model expressing human amyloid precursor protein (APP) with the Arctic mutation 下载免费PDF全文
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The maximum aerobic power and aerobic efficiency (anaerobic threshold) have been determined in major league soccer players. The aerobic capacity of soccer players from leading Russian teams is substantially lower than that of players from leading European teams. 相似文献
146.
Jabmila Solábová T. Herben Libuše Pavlová Kateřina Pánková J. Tupý 《Biologia Plantarum》1985,27(2-3):237-240
147.
A V Pavlov 《Arkhiv anatomii, gistologii i émbriologii》1988,95(7):51-54
By means of cytometry estimation of mitotic index and nucleo-cytoplasmic relation of parathyrocytes, parathyroid glands have been studied in 52 white rats and 28 white mice under conditions of intal inhibition (30 mg/kg of body mass twice a day intraperitoneally) of tissue basophils (TB) secretory activity. For stimulation of the glands, repeated injections of trilon B and hemiparathyroidectomy are used. The experiment lasts for 3.5 days. In the rat parathyroid glands, containing a considerable amount of TB, intal does not produce any important effect of quantitative parameters of the organ's structure in intact animals, nevertheless it prevents development of hypertrophy of the parathyrocytes in the stimulated glands, as well as makes weaker the proliferative response of the cells to hemiparathyroidectomy. In mice, their parathyroid glands containing single TB, under conditions of stimulation of the parathyroid function, intal does not produce any inhibitory effect to growth of middle size parathyrocytes. The results obtained demonstrate that the parathyroid TB actively participate in regulation of the organ's morphofunctional state, intensifying the stimulating effect of hypocalcaemia to the parathyroid parenchyma. 相似文献
148.
D. S. Pavlov A. E. Veselov V. V. Kostin D. A. Efremov M. A. Ruchiev S. B. Tuniev 《Journal of Ichthyology》2018,58(1):93-103
Conditions of reproduction and distribution of the Black Sea trout Salmo trutta labrax in the basin of the Mzymta River after Olympic objects′ construction are considered. In the main river channel of the Mzymta, the structure of spawning and nursery grounds are destroyed along 57 km from the river mouth. The total area of these grounds in the Mzymta basin is 572800 m2, and 49% of this area is situated above the dam of the Krasnopolyanskaya Power Plant and is inaccessible for spawners of the migratory form of the Black Sea trout listed in the Red Data Book of the Russian Federation. Consequently, natural reproduction of the migratory form discontinued. The resident form of trout still exists in the upper parts of the Mzymta and in 19 of its tributaries not affected by construction. On the 2.4-km-long stretch of the riverbed situated below the inflow of the Pslukh tributary, the substrate is in the process of natural restoration due to the descent of mudslides followed by washing of the substrate by the flow. The river is partially inhabited by trout individuals from habitats not affected by construction. 相似文献
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