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101.
The effect of triiodothyronine (T3′) on the uptake of several amino acids into the amino acid pools and into proteins of Rana catesbeiana tadpole liver and tail muscle and tail fin has been studied. Labeling of the alanine and glycine pool was stimulated in the liver more than the leucine pool. After exposure to T3 for 3 days, uptake of α-aminoisobutyric acid (a transport model substrate) into liver was stimulated about 55%. In tail tissues uptake of leucine was stimulated but uptake of alanine was depressed by T3. Incorporation of leucine and alanine into tissue protein was stimulated in the liver but inhibited in tail tissues after T3 injection.Changes in other macromolecules and ATP and ADP levels in liver and tail muscle were also investigated during induced metamorphosis. In the liver, the total DNA content did not change, but the RNA and protein content per liver increased significantly. The increase in RNA/DNA and protein/DNA ratios, suggested that liver cells underwent hypertrophy during induced metamorphosis. The ATP level showed a transient decrease after 3 days of T3 treatment. In tail muscle, protein and RNA content decreased as the muscle regressed, but the DNA content and ATP level remained unchanged throughout the experimental period. 相似文献
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Shoot tips, cotyledonary nodes and hypocotyls of chickpea (Cicer arietinum L.) were grown on 3 media: plant induction medium
(PIM), callus induction medium (CIM), and shoot induction medium (SIM). Maximum growth and differentiation was seen in PIM,
whereas minimum was observed in CIM. Shoot tips which differentiated to multiple shoots evolved negligible amounts of ethylene.
Maximum ethylene evolution was recorded by hypocotyls in PIM. Ethylene appears to have stimulatory effect on shoot bud differentiation
in cotyledonary nodes. But in hypocotyls, increased ethylene inhibited growth and differentiation. Calli on media containing
only auxin (PIM) evolved significantly more ethylene, whereas those on media with cytokinin (SIM) evolved more methane. Callus
forming explants like cotyledonary nodes and hypocotyls evolve more ethylene than shoot tips.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Dr. agr. Chandra Bhushan Prasad Mishra Prof. Dr. agr. habil. Lothar Behr 《Archives Of Phytopathology And Plant Protection》2013,46(6):373-376
Abstract In Anbetracht der weitreichenden Bedeutung des VIII. Internationalen Pflanzenschutzkongresses, der in der Zeit vom 22. bis 26. August 1975 in Moskau stattfand, hält es die Redaktion für erforderlich, die anläßlich des Kongresses verabschiedete Resolution im Wortlaut wiederzugeben. 相似文献
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