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51.
Production of trichothecene and non-trichothecene mycotoxins by Fusarium species isolated from maize in Minnesota 总被引:1,自引:0,他引:1
Eighty-two cultures of Fusarium species isolated in 1986 from moldy maize in Minnesota were each cultured on rice for 4 weeks and found to produce the following mycotoxins: F. graminearum isolates, deoxynivalenol (DON, 4–225 g/g), 3-acetyldeoxynivalenol (3-ADON, 2–4g/g), 15-acetyldeoxynivalenol (15-ADON, 1–35 g/g) and zearalenone (ZEA, 5–4350 g/g); F. moniliforme, fusarin C (detectable amounts to 1000 g/g); F. mòniliforme, F. oxysporum, F. proliferatum and F. subglutinans isolates, moniliformin (15–6775 g/g); F. moniliforme, F. proliferatum, and F. subglutinans isolates, fusaric acid (detectable amounts). Other mycotoxins screened for in each rice sample and not detected were T-2 toxin, HT-2 toxin, neosolaniol, T-2 tetraol, nivalenol, fusarenon-X, scirpenols, alpha and beta trans-zearalenols, wortmannin, and fusarochromanone. The rat feeding bioassay indicated that other, unidentified toxins may be present. 相似文献
52.
J. Michalov 《Biologia Plantarum》1989,31(4):292-301
An analysis of flows through primary root and first node root tissues of plants grown under conditions of salinity and nutrient
deficiency induced by temperature gradients was carried out using. a mathematical model. The results obtained show that high
KNO3 concentration in Knop’s nutrient solution (salinity) causes an inhibition of volume and heat flows and that the omission
of KNO3 from Knop’s nutrient solution (deficiency) stimulates these flows. The causes of the inhibition lay in the fact that salinity
reduced hydraulic, electric, and osmotic conductivity when compared with the control (Knop’s solution), but relative to nutrient
deficiency, it increased osmotic conductivity, electrodiffusion, diffusion, and filtration of heat flow induced by the electric
and heat power. The causes of the stimulation were that deficiency partially decreased conductivities, similarly as salinity
when compared with the control, and also decreased osmotic abilities of the system. By contrast, it increased heat conductivity
and corresponding filtrations (diffusion-thermal, thermoosmotic). In first node root tissues, it increased all conductivities
with the exception of electric conductivity, then osmotic, electroosmotic, diffusion, electrodiffusion, and filtration of
heat flow and current flow, that is the number of possible ways of solution transport through root tissues increased.
Part II. 相似文献
53.
J. A. Thornton 《Hydrobiologia》1989,183(3):i
Contents of volume 183, 1989 相似文献
54.
Propionate metabolism in a methanogenic enrichment culture. Direct reductive carboxylation and acetogenesis pathways 总被引:1,自引:0,他引:1
Abstract Serial dilutions of methanogenic sludges in propionate medium gave a methanogenic non-acetoclastic enrichment degrading 1 mol of propionate to 1.6 mol of acetate and 0.17 mol of methane, with a transient accumulation of butyrate. NMR recordings showed the conversion of [2-13 C]- and [3-13 C]-propionate to [3-13 C]- and [4-13 C]-butyrate, respectively, thus demonstrating a reductive carboxylation of propionate to butyrate. The labelling found in the accumulated acetate and fermentation balances also suggested that reductive carboxylation was the major pathway involved in propionate conversion to acetate. 相似文献
55.
Summary When 458 parents of children suffering from cystic fibrosis (CF) from all over the German Democratic Republic were interviewed to determine the number of their siblings, it was found that the maternal families had a total of 1369 children and the paternal, 1220. While the fathers of CF patients tended to originate from families with one or two children, more mothers than fathers came from families with three to twelve children (P=0.01). The average number of children in the maternal families was 2.99; in the paternal families, only 2.66. To rule out any methodological errors, sibs of mothers and fathers of various control groups were studied. We found that the number of siblings in these groups was balanced. The differences in our findings are probably due to CF heterozygosity. The underlying mechanism is unknown. 相似文献
56.
57.
One hundred eighty sexually mature Saguinus mystax were imported from Peru in six lots over a period of 1 year. Within 1 year after arrival, the mortality was 60% and the majority of the tamarins showed signs similar to "wasting marmoset syndrome" (WMS). In an effort to improve the survival rate, an open formula diet replaced the commercial closed formula diet that had been fed since arrival of the tamarins. The open formula diet contained 26.2% crude protein, 12.3% ether extract, 43.3% nitrogen free extract and 5.9% crude fiber on a dry matter basis. The diet was evaluated on the basis of palatability, weight gain, mortality, digestibility, nitrogen balance, serum biochemical parameters and blood counts. The mean daily consumption on an as-is basis was 44.8g or 335 Kcal gross energy/Kg of body wt./day. During the 3 month open formula diet evaluation period average weight increased by 56g (p less than .05), mortality decreased demonstratively, and alopecia and chronic diarrhea were nearly eliminated. Mean daily gross energy intake for S. mystax (335 Kcal/Kg of body wt/day) was substantially greater than previously reported values for callitrichids. WMS signs observed in the S. mystax colony were controlled by providing what appears to be an adequate diet. 相似文献
58.
J. Kov 《Engineering in Life Science》1988,8(1):103-110
This paper describes our experience with the use of high performance liquid chromatography in the analysis and preparation of several NAD-dependent dehydrogenases and oxygen-dependent oxidases. The chromatographic materials tested were from Pharmacia (Sweden), LKB (Sweden) and Lachema (Czechoslovakia), the columns were attached to the fast protein liquid chromatographic (FPLC) system from Pharmacia. The preparative use of high performance ion exchange, molecular sieve and hydrophobic interaction chromatographies as well as of chromatofocusing made it possible to prepare tens of milligrams of completely pure enzymes in several hours. In most cases a combination of two high performance methods was sufficient to yield a homogeneous enzyme. The purified enzymes were used as analytical reagents for determining the concentrations of several metabolites and activities of some enzymes. A biotechnological application of immobilized alcohol dehydrogenase for the production of reduced nicotineadenine dinucleotide from the oxidized form of the coenzyme is discussed in a greater detail. 相似文献
59.
60.