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The effect of serotonin after intracerebroventricular (ICV) injections in dosage of 0.3 and 0.15 μg/g of the body weight on the thermoregulatory behavior in juvenile carp Cyprinus carpio L. and goldfish Carassius auratus (L.) has been studied in two experiments of 10- to 11-day duration. It has been found that ICV injection of serotonin in dosage of 0.3 μg/g caused the initial decrease in preferred temperatures (PT) (2–3 days) followed by their further increase (4–8 days after the administration) in carp. ICV injection of serotonin in dosage of 0.15 μg/g caused more durable initial decrease in PT (2–8 days) followed by the increase of once (9–11 days of observation) in goldfish. The values of the ultimate preferred temperature in fish of the experimental group exceeded that in control specimens by 4.1 °C at the first experiment and by 3.1 °C in the second experiment. The data for the first time demonstrated long-term effect of a single ICV injection of serotonin on the thermoregulatory behavior in two closely related species of teleosts.  相似文献   
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Eurasian Soil Science - A comparative assessment of the carbon stock in loamy soils (Albic Retisols) of coniferous–broadleaved forests on the Moskvoretsko-Oksky Plain and sandy soils (Albic...  相似文献   
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Recent numerical simulations have yielded the most efficient geodynamo, having the largest dipole intensity when reversal frequency is low. Reliable paleointensity data are limited but heretofore have suggested that reversal frequency and paleointensity are decoupled. We report data from 56 Thellier-Thellier experiments on plagioclase crystals separated from basalts of the Rajmahal Traps (113 to 116 million years old) of India that formed during the Cretaceous Normal Polarity Superchron. These data suggest a time-averaged paleomagnetic dipole moment of 12.5 +/- 1.4 x 10(22) amperes per square meter, three times greater than mean Cenozoic and Early Cretaceous-Late Jurassic dipole moments when geomagnetic reversals were frequent. This result supports a correlation between intervals of low reversal frequency and high geomagnetic field strength.  相似文献   
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The activity of antioxidant enzymes and ultrastructural changes in tissues inoculated with P. infestans isolate have been studied in the previously developed independent transgenic lines of tomato with FeSOD1 gene and control plants. It is shown that the activity of superoxide dismutase is significantly higher in transgenic plants than that in control plants (nontransgenic plants). Chlorosis and obvious changes in tissue turgor were observed when the control tomato plants were inoculated, which indicates irreversible damages and unimpeded progression of infection. At the same time, the transgenic lines were characterized by the formation of clearly limited zones of damaged cells that rapidly arrested the infection. In addition, the damages differed from those in nontransgenic plants: the cells along the edges of the infection site were smaller and had heavy invaginations of the cell wall. The contacts between the cells were disrupted in this zone, but they were preserved in undisturbed zones of the tissue. Thus, the expression of the FeSOD1 transgene promotes the emergence of the resistance to P. infestans in tomato transgenic plants.  相似文献   
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The resistance of transgenic tomato plants containing genes of chitin-binding proteins from Amaranthus caudatus (ac) and A. retraflexus (RS-intron-Shir) and hevein-like antimicrobial peptides (amp1 and amp2) from Stellaria media is analyzed. Lines expressing genes ac, amp1, and amp2 are characterized, unlike the untransformed control, by enhanced resistance to a isolate Phytophthora infestans obtained from potato leaves.  相似文献   
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