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1.
Jacek Kęsy Beata Maciejewska Magdalena Sowa Magdalena Szumilak Krzysztof Kawałowski Maja Borzuchowska Jan Kopcewicz 《Plant Growth Regulation》2008,55(1):43-50
It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production
is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of
IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis
and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis. 相似文献
2.
Anna Nowakowska-Waszczuk Andrzej Sokoŀowski 《Applied microbiology and biotechnology》1987,26(4):363-364
Summary In an air-lift fermenter, the following production was obtained from 125 g sucrose in mineral medium at pH 2.5 : 15.76 g mycelium dry wt, 107.2 g citric acid anhydrous and 0.594 mol CO2 within 138 h (run I) and 13.72 g mycelium dry wt, 114.28 g citric acid and 0.516 mol CO2 within 144 h (run II). Initially, the carbon content of consumed sugar and products did not balance. At the end of fermentation, the carbon content of the products was 0.9%–5.5% higher than that of the consumed sugar. For the purpose of the calculations the carbon content in mycelium was accepted as 0.462.The work was a part of Project No 04.11 CPBP, topic No 2.24 相似文献
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Yellow lupin nodule specific sequences were selected by screening of cDNA library prepared from lupin nodule poly(A)+RNA. From about 3,000 clones containing fragments of lupin DNA 150-1,500 base pair long, 7% of clones carrying nodule specific sequences were identified. Among them the most abundant sequence species, represented by 32% clones, encodes leghemoglobin. Another abundant species designated pLN13 is represented by 13% clones. The Northern blot analysis of lupin mRNA confirmed nodule specificity of the cloned sequences. The nucleotide sequence of one clone, pLN281 of 225 bp, is presented. 相似文献
5.
The effect of tin and lead on levels of essential metals (Zn, Cu, Ca, Fe) in rabbit tissues was compared in relation to the route of administration. Animals received intraperitoneally, or per os, SnCl2 (2 mg Sn/kg) or Pb(CH3COO)2 (3.5 mg Pb/kg) every day for 5 d or for 1 mo. Copper, zinc, iron, and calcium were determined by AAS in the liver, kidneys, spleen, brain, bone marrow, and blood; lead and tin concentration were measured in the blood of animals. Tin and lead administered per os caused either no changes or the decreased concentration of endogenous metals in several tissues. The other route of administration (ip) of both metals generally contributed to the increased storage of essential elements. Blood tin levels of tin treated animals were only about less than or equal to 1/10 of blood lead concentrations of rabbits exposed to lead. 相似文献
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It was shown in the mathematical model described elsewhere that when growth rate of the chicks is maximized and not constrained by the food availability, the optimal relationship between body mass and alimentary tract mass should conform to a single straight line, or two-, or three-segmented straight lines. Here, we present the data on growth of 11 bird species, and we test the model using the mass of intestines as an indicator of growth of the alimentary tract. The results support the predictions of the model for altricial species and contradict them for precocials. Since precocial species examined here were not food-limited, we suggest that the lack of optimal growth of their alimentary tract is inherent to their mode of development. This may account for their lower growth rate, as compared to altricials. The existence of the optimal growth of the alimentary tract in altricial nestlings suggests that under natural conditions the food is much more abundant than it is generally assumed. 相似文献
7.
Andrzej Paszczyński Jan Fiedurek Zdzislaw Ilczuk Grażyna Ginalska 《Applied microbiology and biotechnology》1985,22(6):434-437
Summary Two proteases from Aspergillus niger C post-culture medium were isolated by fractionation on a DEAE-sepharose column and ultrafiltration. The four fractions of glucoamylase activity (GA1, GA2, GA3 and GA4) present in the medium showed different susceptibility to the influence of proteases. The effects of proteases on the different glucoamylase fractions during the growth of the fungus are demonstrated. The activity was found to decrease at the beginning of the culture, but by its end there was a stimulation of GA4 glucoamylase. After treating GA2 and GA3 with protease II, a new additional fraction of glucoamylase was detected. 相似文献
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Summary A new form of ectodermal dysplasia was observed in two siblings, offspring of healthy non-consanguineous parents. The main findings in both children are: hypodontia, abnormally shaped teeth, scalp hypotrichosis, pili annulati, follicular hyperkeratosis on the trunk and limbs, intensified delineation and reticular hyperpigmentation of the nape, and hyperopia; one of the siblings also has astigmatism. As both patients have normal nails and are euhidrotic, this is an ectodermal dysplasia of the pilodental subgroup. The cause is probably genetic and autosomal-recessive inheritance is most likely. 相似文献
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