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51.
The genetic determination of variability of barley doubled haploid (DH) lines in regard of their susceptibility to Fusarium head blight caused by Fusarium culmorum was studied. The susceptibility was evaluated in 3-year field experiment on the basis of reduction in yield traits and myotoxin accumulation in infected kernels. The following traits were analysed in inoculated and control plants: kernel number and weight per ear, 1000-kernel weight, percentage of plump kernels (>2.5 mm), deoxynivalenol (DON) content and nivalenol (NIV) content of kernels. On the basis of the obtained data, heritability coefficient (ratio of genotypic to phenotypic variance) was assessed, and genetic parameters as well as the number of effective factors were estimated. Heritability coefficients calculated from two-way analysis of variance, i.e.regarding the influence of years and year x genotype interaction, appeared to be exceptionally low and ranged from 5.2% for the reduction in plump kernels to 38.2% for the reduction in 1000-kernel weight. In the case of mycotoxin accumulation about 60% of the observed variability in NIV concentrations and 30% in DON concentration resulted form genetic differences among lines. Additive effects of genes were important for all the analysed traits. Significant effects of dominance and dominance x dominance were observed for 1000-kernel weight and percentage of plump kernels. Moreover, it was found that the observed variability in yield trait reduction resulted from segregation of 5-6 effective factors, DON contents from 4 factors, while NIV content from 5 factors.  相似文献   
52.
Increase in obesity rates and obesity associated health issues became one of the greatest health concerns in the present world population. With alarming increase in obese percentage there is a need to design new drugs related to the obesity targets. Among the various targets linked to obesity, pancreatic lipase was one of the promising targets for obesity treatment. Using the in silico methods like structure based virtual screening, QikProp, docking studies and binding energy calculations three molecules namely zinc85531017, zinc95919096 and zinc33963788 from the natural database were reported as the potential inhibitors for the pancreatic lipase. Among them zinc95919096 presented all the interactions matching to both standard and crystal ligand and hence it can be further proceeded to drug discovery process.  相似文献   
53.
We have shown that niacin deficiency impairs poly(ADP-ribose) formation and enhances sister chromatid exchanges and micronuclei formation in rat bone marrow. We designed the current study to investigate the effects of niacin deficiency on the kinetics of DNA repair following ethylation, and the accumulation of double strand breaks, micronuclei (MN) and chromosomal aberrations (CA). Weanling male Long-Evans rats were fed niacin deficient (ND), or pair fed (PF) control diets for 3 weeks. We examined repair kinetics by comet assay in the 36 h following a single dose of ethylnitrosourea (ENU) (30 mg/kg bw). There was no effect of ND on mean tail moment (MTM) before ENU treatment, or on the development of strand breaks between 0 and 8 h after ENU. Repair kinetics between 12 and 30 h were significantly delayed by ND, with a doubling of area under the MTM curve during this period. O6-ethylation of guanine peaked by 1.5 h, was largely repaired by 15 h, and was also delayed in bone marrow cells from ND rats. ND significantly enhanced double strand break accumulation at 24 h after ENU. ND alone increased chromosome and chromatid breaks (four- and two-fold). ND alone caused a large increase in MN, and this was amplified by ENU treatment. While repair kinetics suggest that ND may be acting by creating catalytically inactive PARP molecules with a dominant-negative effect on repair processes, the effect of ND alone on O6-ethylation, MN and CA, in the absence of altered comet results, suggests additional mechanisms are also leading to chromosomal instability. These data support the idea that the bone marrow cells of niacin deficient cancer patients may be more sensitive to the side effects of genotoxic chemotherapy, resulting in acute bone marrow suppression and chronic development of secondary leukemias.  相似文献   
54.
The present study examined the physiological impact of a school based sprint interval training (SIT) intervention in replacement of standard physical education (SPE) class on cardio-respiratory fitness (CRF) and glucose homeostasis during the semester following summer vacation. Participants (n=49) were randomly allocated to either intervention (SIT; n=26, aged 16.9 ± 0.3 yrs) or control group who underwent standard physical education (SPE; n=23, aged 16.8 ± 0.6 yrs). CRF (VO2max) and glucose homeostasis were obtained prior-to and following 7 weeks of SIT exercise. Significant group x time interaction was observed for CRF (P < 0.01) with non-significant trends for fasting insulin (P= 0.08), and HOMA-IR (P=0.06). CRF decreased (P < 0.01) in SPE such that POST intervention CRF was significantly lower (P< 0.05) in SPE. Fasting plasma glucose (P < 0.01), insulin (P< 0.01) and HOMA-IR (P< 0.01) increased significantly amongst SPE. The main finding of the present study is that 7-weeks of SIT exercise is an effective method of maintaining (but not improving) CRF and fasting insulin homeostasis amongst school-going adolescents. SIT exercise demonstrates potential as a time efficient physiological adjunct to standard PE class in order to maintain CRF during the school term.  相似文献   
55.
56.
Andrew JS Coats 《Trials》2000,1(3):155-6
Chronic heart failure (CHF) is a common condition with a poor prognosis. It is associated with poor exercise tolerance and debilitating symptoms. These symptoms appear to be associated with pathophysiological changes that occur systemically in the patient with CHF. Exercise training in carefully selected patients has been shown to be safe and to improve exercise capacity. Many of the pathophysiological abnormalities of CHF are improved by training. Some studies have suggested a possible improvement in morbidity and mortality with training. This review analyzes the controlled clinical trials of exercise training in CHF published to date.  相似文献   
57.
The aim of the study was to estimate occurrence of ochratoxin A (OA) in feeds and the metabolite residues in porcine blood serum in Poland. Samples were collected in the period from February to May, 1999, in the southern Wielkopolska region. Altogether 40 and 45 samples of feed and porcine blood serum, respectively, were analyzed for OA. Percentage of samples contaminated with OA, both in case of feeds and blood, collected in the winter season was considerably higher than that for the spring season. The percentages for feeds were as follows: 47.6 and 26.3 %, while for porcine serum: 66.7 and 50.0 %, respectively winter and spring. In 25 % of cases ochratoxin A was present in both types of investigated material (feed, blood), whereas in 27.5 % of samples this metabolite was detected in blood only, or in 7.5 % only in the feed. The presence of OA was found neither in the feed nor in the serum in 40 % of all cases. In subgroups (feed, blood) the concentration in the whole collective of positive samples were in the range 0.3–13.5 ng/g and 0.3–69.5 ng/ml, respectively, while median values were 2.3 ng/g and 6.0 ng/ml. Only one feed and three porcine serum samples, were found to be contaminated at concentration levels higher than 10 ng/g or 10 ng/ml.  相似文献   
58.
Beauvericin Production by Fusarium Species   总被引:5,自引:0,他引:5       下载免费PDF全文
Beauvericin is a cyclohexadepsipeptide mycotoxin which has insecticidal properties and which can induce apoptosis in mammalian cells. Beauvericin is produced by some entomo- and phytopathogenic Fusarium species (Fusarium proliferatum, F. semitectum, and F. subglutinans) and occurs naturally on corn and corn-based foods and feeds infected by Fusarium spp. We tested 94 Fusarium isolates belonging to 25 taxa, 21 in 6 of the 12 sections of the Fusarium genus and 4 that have been described recently, for the ability to produce beauvericin. Beauvericin was produced by the following species (with the number of toxigenic strains compared with the number of tested strains given in parentheses): Fusarium acuminatum var. acuminatum (1 of 4), Fusarium acuminatum var. armeniacum (1 of 3), F. anthophilum (1 of 2), F. avenaceum (1 of 6), F. beomiforme (1 of 1), F. dlamini (2 of 2), F. equiseti (2 of 3), F. longipes (1 of 2), F. nygamai (2 of 2), F. oxysporum (4 of 7), F. poae (4 of 4), F. sambucinum (12 of 14), and F. subglutinans (3 of 3). These results indicate that beauvericin is produced by many species in the genus Fusarium and that it may be a contaminant of cereals other than maize.  相似文献   
59.
Liu  JS; Sabatti  C 《Biometrika》2000,87(2):353-369
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60.
Sensitivity to ozone is highly variable in cultivars of different wheat species, leading to differences in leaf injury and yield. Not much is known about the physiological background of these differences. The objective of this study was to compare the effects of ozone on photosynthetic parameters in Triticum aestivum L. (spring wheat cv. Nandu, winter wheat cv. Perlo) and Triticum durum Desf. (cv. Extradur). Plants cultivated in pots were exposed to 80 nmol mol?1 ozone, or were used as control plants in a greenhouse. Stages of growth and senescence of single leaves were recorded. Light-saturated net photosynthesis, leaf conductance for water vapour, and chlorophyll fluorescence were measured. Stomatal limitation was calculated from CO2 response curves, and the free radical content of whole leaves measured by EPR spectroscopy. Senescence of single leaves was enhanced by the ozone-treatment in all three cultivars, in the order Nandu > Perlo > Extradur. Development of whole plants was slightly delayed in Perlo and Nandu, but was accelerated significantly in Extradur. The rate of net photosynthesis under light saturation (Asat) decreased significantly in older, ozone-fumigated leaves of Perlo and Nandu but not of Extradur. Leaf conductance (g1) showed a similar behaviour, but stomatal limitation (l) was similar between ozone-treated and control plants. Thus, an ozone-induced closure of stomata was not the reason for the observed difference in Asat. Perlo and Nandu showed a significant, only partly reversible decrease in Fv/Fm in ozone-fumigated leaves, whereas in Extradur the decrease was fully reversible only in older leaves. Whole leaves of Extradur, in contrast to Perlo and Nandu, showed no increase in EPR free radical signals. The higher ozone tolerance of Extradur was thus not caused by decreased ozone uptake via the stomata, but by a better ability of photosynthetically active mesophyll cells to cope with photooxidative stress.  相似文献   
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