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101.
High year-to-year variability in the incidence of Fusarium spp. and mycotoxin contamination was observed in a two-year survey investigating the impact of maize ear rot in 84 field samples from Germany. Fusarium verticillioides, F. graminearum, and F. proliferatum were the predominant species infecting maize kernels in 2006, whereas in 2007 the most frequently isolated species were F. graminearum, F. cerealis and F. subglutinans. Fourteen Fusarium-related mycotoxins were detected as contaminants of maize kernels analyzed by a multi-mycotoxin determination method. In 2006, a growth season characterized by high temperature and low rainfall during anthesis and early grain filling, 75% of the maize samples were contaminated with deoxynivalenol, 34% with fumonisins and 27% with zearalenone. In 2007, characterized by moderate temperatures and frequent rainfall during the entire growth season, none of the 40 maize samples had quantifiable levels of fumonisins while deoxynivalenol and zearalenone were detected in 90% and 93% of the fields, respectively. In addition, 3-acetyldeoxynivalenol, 15-acetyldeoxnivalenol, moniliformin, beauvericin, nivalenol and enniatin B were detected as common contaminants produced in both growing seasons. The results demonstrate a significant mycotoxin contamination associated with maize ear rots in Germany and indicate, with regard to anticipated climate change, that fumonisins-producing species already present in German maize production may become more important.  相似文献   
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There is increasing evidence that reactive oxygen species arising from several enzymatic reactions are mediators of inflammatory events. Plant preparations have the potential for scavenging such reactive oxygen species. Flavans and procyanidins are bioavailable and stable during the process of cooking. This study used conditions that mimicked digestion of Vitis vinifera seed powder in the stomach (acidic preparation) and small intestine (neutral preparation). The flavonoids of these two preparations were released during simulated digestion and were determined with HPLC analysis. Biochemical model reactions relevant for the formation of reactive oxygen species in vivo at inflammatory sites were used to determine the antioxidant properties of the two preparations. The inhibition of the indicator reaction for the formation of reactive oxygen species represents a potential mechanism of the physiological activity of the corresponding preparation. The results of this work show clearly that the polyphenols released during the simulated digestion of the two preparations have good scavenging potential against superoxide radicals, hydroxyl radicals, and singlet oxygen. They protect low-density lipoprotein against copper-induced oxidation due to the copper-chelating properties and their chain-breaking abilities in lipid peroxidation.  相似文献   
104.
The antioxidant activity of a commercial rectified clove leaf essential oil (Eugenia caryophyllus) and its main constituent eugenol was tested. This essential oil comprises in total 23 identified constituents, among them eugenol (76.8%), followed by beta-caryophyllene (17.4%), alpha-humulene (2.1%), and eugenyl acetate (1.2%) as the main components. The essential oil from clove demonstrated scavenging activity against the 2,2-diphenyl-1-picryl hydracyl (DPPH) radical at concentrations lower than the concentrations of eugenol, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA). This essential oil also showed a significant inhibitory effect against hydroxyl radicals and acted as an iron chelator. With respect to the lipid peroxidation, the inhibitory activity of clove oil determined using a linoleic acid emulsion system indicated a higher antioxidant activity than the standard BHT.  相似文献   
105.
Objective— To compare tibial plateau rotation after tibial plateau leveling osteotomy with the radiographically planned rotation and to determine the effect of translations and rotations of the tibial plateau fragment on the biomechanical stability of the construct under cyclic loading.
Study Design— Experimental biomechanical study.
Animals— Cadaveric canine pelvic limbs (n=10).
Methods— Titanium pins were inserted into the tibial plateau and the proximal metaphysis to track the fragment movements by means of computed tomography (CT) imaging. CT scans were performed (1) before osteotomy, (2) after osteotomy and tibial plateau rotation, and (3) after stabilization with plate and screws. The bones were then cyclically loaded in axial compression.
Results— The radiographically planned tibial plateau rotation correlated significantly with the achieved rotation (r=0.73, P =.016), although deviations of up to 4.7° were observed. A significant positive correlation between the amount of rotation about the sawing axis and the plastic deformation of the construct after 30,000 test cycles could be found (r=0.81, P =.005).
Conclusion— Considerable deviation occurred between planned and achieved rotation of the tibial plateau fragment. Lower degrees of rotation were beneficial for biomechanical stability.
Clinical Relevance— Dogs with larger tibial plateau angles may be at a relatively higher risk for fixation failure, but further studies are needed to establish a safe margin of tibial plateau rotation.  相似文献   
106.
For initial training, horses are often transferred from group housing to individual boxes, which is a potential stressor. In this study, salivary cortisol concentrations, locomotion activity, and heart rate (HR) were analyzed and the HR variability (HRV) variables standard deviation of beat-to-beat interval (SDRR) and root mean square of successive RR differences (RMSSD) were calculated in 3-year-old mares (n = 8). Mares were transferred abruptly from a group stable with access to a paddock to individual boxes without a paddock and were studied from 4 days before to 5 days after changing the stable. Mares underwent routine equestrian training for young horses. On the days before mares were moved to individual boxes, cortisol concentrations showed a diurnal rhythm with values approximately 0.6 ng/ml in the morning and a decrease throughout the day. When horses were moved to individual boxes, cortisol concentrations increased to 1.8 ± 0.2 ng/ml within 30 minutes and did not return to baseline values within 6 hours (0.7 ± 0.1 ng/ml, P < .05 over time). On the following days, a diurnal rhythm was re-established but at a higher level than before the change of stable. Locomotion activity was higher when mares had access to a paddock than when kept in individual boxes. Heart rate increased for approximately 60 minutes when mares were separated from their group. In conclusion, separating young horses from their group and individual stabling are perceived as stressful.  相似文献   
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We studied the performance of different seed mixtures and the influence of liming on the establishment of a montane pasture under acidic site conditions during a wood-pasture separation process from 1998 to 2001 in Styria, Austria. Two treatments (with and without liming) were established, each with four seeding treatments (without seeding, commercial, site-adapted and site-specific mixtures), and all plots were regularly fertilized from 1998 to 2002. Vegetation surveys and forage analyses regarding development of vegetation cover, seeded species persistence, quality and yield parameters were conducted again in 2014 and 2016; soil samples were taken in 2015. After cessation of regular fertilization, the analysed soil parameters declined to levels that were sufficient or low for grasslands. pH decreased again over time, but still was significantly higher (p = .0034) in the liming treatment. The single liming during experimental set-up also caused better long-term performance for nearly all vegetation, quality and yield parameters. The site-specific seed mixture performed best regarding most analysed parameters, under both liming treatments. Concerning seeded species, the habitat-typical species Agrostis capillaris, Festuca rubra agg. and Trifolium repens persisted best with and without liming. All analysed vegetation and yield parameters stayed far behind their results of 2001 and their potential. The use of site-specific seed mixtures supports the establishment of productive grassland on specific locations. The long-term results also illustrated that even low-input management like liming in multi-annual intervals can help to improve acidic site and growing conditions significantly and thereby increases the sustainability of cost-intensive wood-pasture separation processes under similar conditions.  相似文献   
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