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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
357.
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
358.
An investigational drug (2-picoline, 6-amino-4-nitro-, 1-oxide) was evaluated to characterize the anti-coccidial spectrum of the compound. Two concentrations of the drug (125 and 250 ppm) were evaluated for bioactivity; weight gain, survival, dropping, and lesion scores were the response variables utilized to ascertain activity. The activities of the picoline derivative were compared with monensin, maduramicin, and a narasin/nicarbazin (1:1) combination. The investigational drug had significant activity against Eimeria tenella and Eimeria necatrix, and the 250-ppm level was significantly more active than 125 ppm. At 250 ppm, the E. tenella activity of the picoline derivative was comparable to both monensin (120 ppm) and the 50-ppm narasin/nicarbazin combination, significantly less effective than maduramicin (6 ppm), and significantly more efficacious than 30 ppm narasin/nicarbazin. At the same level (250 ppm), the picoline derivative had significantly less E. necatrix activity than monensin (120 ppm), maduramicin (6 ppm), and narasin/nicarbazin (50 ppm), and significantly greater activity than 30 ppm narasin/nicarbazin. At best, only extremely weak Eimeria acervulina, Eimeria brunetti, and Eimeria maxima activities were noted with the investigational drug; higher concentrations of the picoline derivative may achieve greater anti-coccidial activity against these species. The efficacy of narasin/nicarbazin compared favorably with monensin and maduramicin; the 50-ppm level of the combination appeared significantly more efficacious than 30-ppm. 相似文献
359.
The dopamine metabolite, homovanillic acid, decreases in concentration in plasma between 8:30 A.M. and 12:30 P.M. In patients with schizophrenia this cyclic change is attenuated by chronic neuroleptic treatment; however, if the 8 A.M. dose of neuroleptic is omitted, the decrease in level occurs. Presuming that neuroleptics attenuate the decline through a receptor mediated compensatory increase in dopamine release, it would appear that receptors are not fully occupied by neuroleptics even at therapeutically effective doses. The usual morning decrease in plasma cortisol levels was unaffected by neuroleptics. 相似文献
360.
The study of water relaxation rates of solutions of melanins with paramagnetic metal ions provides a powerful tool for investigating the binding sites and for obtaining useful structural and dynamic information. The measure of 1H- and 2H-longitudinal and transverse relaxation rates at a single, high-magnetic field for H2O/D2O (80:20) solutions allows the determination of tau c, tau R, tau e, tau M, r, q, and Z (the outer sphere contribution to the overall relaxation rate) for Mn(II)-L-Dopa melanin system. 相似文献