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61.
Pospisilova J; Wilhelmova N; Synkova H; Catsky J; Krebs D; Ticha I; Hanackova B; Snopek J 《Journal of experimental botany》1998,49(322):863-869
Plantlets of Nicotiana tabacum L. cv. Petit Havana SR1
were grown in vitro on Murashige and Skoog medium
containing 2% saccharose, and then transplanted ex
vitro into pots with coarse sand and Hewitt nutrient solution.
In the first day after transplantation, the anti-transpirant abscisic acid
(ABA; 0.01, 0.05 or 0.10 mM) was added to the substrate. Leaf stomatal
conductance (gs), which was high in plants during the
first days after transplantation similarly as in plantlets grown
in vitro, was considerably decreased by ABA-treatment.
However, in the further days gs decreased more quickly
in control than in ABA-treated plants, and after 2 or 3 weeks
gs was significantly lower than that of plantlets
grown in vitro but similar in control and ABA-treated
plants. Two weeks after transplantation, net photosynthetic rate,
chlorophyll a + b content,
maximal photochemical efficiency, and actual quantum yield of photosystem
II in plant leaves were higher in comparison with those in plantlets grown
in vitro. ABA-treatment had slight positive or
insignificant effect on photosynthetic parameters and enhanced plant
growth. Thus ABA application can alleviate 'transplant shock' and speed up
acclimation of plantlets to ex vitro
conditions. 相似文献
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Summary The child with iminoglycinuria is in our observation. Hyperprolinuria was seen at 5 months by screening program. The child was repeatedly examined in the hospital and was seen last time at 16 months. IQ was 67, in the urine were excessive amounts of glycine, proline a hydroxyproline. In the blood aminoacids were in normal levels. In the child was noticed the same increase of proline in the blood as in the control child of the same age following loading test with L-proline, indicating normal intestinal absoption. Both parents and father's sister's 2-year-old mentally retarded child exhibit excessive glycinuria. The father, his sister, father's father, and grandfather are partialy, congenitaly deaf. 相似文献
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A mathematical model of errors of the spleen colony technique is applied to data obtained from four mouse strains and F1 hybrids. the variance of the colony counts was close to the Poisson distribution in inbred mice and F1 hybrids. However, it should be checked regularly. the magnitude of the error in CFU-s determination and of the estimations of the S phase fraction was derived, and is presented relative to the mean colony counts for all mouse strains studied. the optimum spleen colony counts are generally higher than those which are commonly used. However, the utilization of the optimum spleen colony counts requires a correction for the effect of colony overlap. 相似文献
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Various theories have been put forward to explain the regenerative capacity of liver tissue induce by partial hepatectomy (PH). One of them presumes the existence of humoral factors stimulating proliferation of the liver tissue. We evaluated the course of liver regeneration after 65-70% PH as influenced by dialysates (DIA) of the organs of a rat killed 17 h after PH. In addition to kidney DIA, we were particularly interested in the effect of liver and spleen DIA. The experiments were carried out on rats weighting 310-370 g. Kidney, liver or spleen dialysate was administered subcutaneously and the rats were killed 12 or 24 h later by exsanguination from the abdominal aorta. In further rats, PH was performed 24 h after administering DIA and the rat were killed 18, 24, 30, 48 and 72 h after the operation. The initiation of liver regeneration was stimulated by all the given DIA, but especially by liver DIA. The faster onset of liver regeneration 18 h after PH in rats given spleen DIA is interesting. DIA did not greatly affect the hepatocytes of intact liver, but accelerated the initiation of liver regeneration after PH by synchronizing the cell cycle of proliferating hepatocytes. DIA obtained 17 h after PH contained substances which primarily stimulated liver DNA synthesis. From the changes in inhibition of the migration of spleen macrophages in the medium containing liver antigens, and from the circulating immunocomplex values, we conclude that DIA activation of the immune system, a well as the hepatic stimulator substance contained in the DIA, participates in acceleration of the liver regeneration process. 相似文献