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E M Nikulina O V Trapezov N K Popova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(6):1142-1146
Content of dopamine in the striatum; of serotonin, 5-hydroxyindolacetic acid and noradrenaline in the hypothalamus, striatum and midbrain was studied in three groups of minks from population of an animal farm, differing by their reaction to humans (cowardly, calm, aggressive). The reaction to humans was estimated by a system of marks at the attempt to catch the mink with a mitten. Aggressive animals had a lowered level of serotonin in the hypothalamus and striatum, a lesser content of serotonin metabolite--5-hydroxyindolacetic acid in the striatum. Minks of different groups did not differ by noradrenaline content, but dopamine level in the striatum of cowardly minks was higher than in calm and aggressive animals. Conclusion is made that polymorphism of behaviour corresponds to polymorphism of the state of monoaminergic systems. 相似文献
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N. L. Biddington P. A. Brocklehurst A. S. Dearman Jane Dearman 《Physiologia plantarum》1982,55(4):407-410
Celery seeds ( Apium graveolens L.) given a germination induction period (3 days imbibition at 17°C in the light) could be prevented from germinating by up to 14 days subsequent exposure to high temperature (32°C), polyethylene glycol (PEG), abscisic acid (ABA) or dark (22°C). When the seeds were returned to 17°C in the light, germination occurred and, except for the high temperature treatment, was more rapid compared to seeds given a germination induction period only.
Celery seeds incubated for 3 days at 17°C in the light and then air-dried at 20°C germinated slowly when re-sown at 17°C in the light, and achieved only 19% germination after 21 days. Exposing the seeds to high temperature, PEG, ABA or dark for up to 14 days before drying maintained seed viability and subsequent germination was faster. The longer treatment periods gave increased benefit, and PEG was the most effective treatment. It is suggested that the effectiveness of the treatments in inducing dehydration tolerance relates to their ability to inhibit germination possibly via their prevention of cell expansion. 相似文献
Celery seeds incubated for 3 days at 17°C in the light and then air-dried at 20°C germinated slowly when re-sown at 17°C in the light, and achieved only 19% germination after 21 days. Exposing the seeds to high temperature, PEG, ABA or dark for up to 14 days before drying maintained seed viability and subsequent germination was faster. The longer treatment periods gave increased benefit, and PEG was the most effective treatment. It is suggested that the effectiveness of the treatments in inducing dehydration tolerance relates to their ability to inhibit germination possibly via their prevention of cell expansion. 相似文献
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A A Grinev E I Samokhvalov N A Petrov S K Vasilenko V P Iuferov 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(9):43-45
The primary structure of hemagglutinin (HA) gene of Influenza virus A/USSR/90/77 (H1N1) variants after 3 and 11 passages has been determined. In the HA1 coding region of mice-adapted virus (11 passages) there are two amino acid substitutions: Thr 89----Ala and Asn 127----Asp. At the first stage of adaptation (3-rd passage) only a single mutation was detected: Asn 127----Asp. The adaptation is accompanied by the loss of specific carbohydrate attachment sites adjacent to the receptor-binding site located at HA1 subunit with a concomitant variation in antigenicity. 相似文献
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