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排序方式: 共有306条查询结果,搜索用时 15 毫秒
51.
52.
Busquets R Puignou L Galceran MT Skog K 《Journal of agricultural and food chemistry》2006,54(21):8376-8384
Genotoxic heterocyclic amines (HAs) are formed via the Maillard reaction and free radical reaction mechanisms when meat or fish is cooked at usual cooking conditions. In this paper, the effect of the addition of red wine was tested to study if it interferes in HA formation. Fried chicken breast was the food item chosen, and three different red wines, characterized in terms of grape varieties, free amino acids, antioxidant properties, and metallic composition, were used to marinate meat prior to the heating process. Unmarinated samples and samples marinated with an ethanol-water mixture provided reference HA levels. The frying experiments were performed under well-controlled temperature and time conditions. The samples were analyzed for HA content using solid-phase extraction and LC-MS/MS. DMIP, PhIP, MeIQx, 4,8-DiMeIQx, IFP, TMIP, harman, and norharman were identified in fried chicken breast. Red wine marinades were found to reduce the formation of some of the HAs formed. PhIP, with a reduction of up to 88%, was the most minimized amine, although the formation of harman was enhanced. 相似文献
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Karin Hultin Jäderlund DVM Kerstin Hansson DVM Anna-Lena Berg DVM pHd Anders Sjöström MD pHd Kristina Narfström DVM PHD 《Veterinary radiology & ultrasound》2003,44(5):581-588
To evaluate the age of fontanelle closure of normal kittens and the size of their lateral ventricles, 50 ultrasonographic examinations using the bregmatic fontanelle as an acoustic window were made. Seven kittens, laboratory animals, were included in the study. To verify the location of the lateral ventricle, two of the kittens were sacrificed as neonates. In one of them ink was injected prior to autopsy into one lateral ventricle under sonographic guidance. In a longitudinal study of five of the kittens, the skull depth and the depth of the central part of the lateral ventricle reproduced in a longitudinal view could be measured up to the age of about 5 months. During that period, the skull depth increased from a median value of 1.95 cm (1.92-1.98) in a seven-day-old cat to 2.58 cm (2.52-2.59) in a 154-day-old cat, while the afore-mentioned ventricle values increased from 0.3 mm to 1.1 mm. 相似文献
55.
前言:过去十几年来,中国已跃居全球最大的木材产品进口国行列。1997~2007年,中国木材进口材积总量(圆木当量)翻了四倍,从大约1250万立方米增长到了5200多万立方米,目前已是全球第一的木材产品进口国。原木增长量占据木材产品进口增长的绝大部分。然而,简单地从经济学角度上看,受目前资源短缺、木材价格上涨和不断攀升的运输费用的影响,进口原木并非效益最佳。那么,如何解释中国为什么倾向于进口原木而不是木制品成品呢? 相似文献
56.
Bacterial wilt incidence was reduced by 38.1% and 100% in silicon-treated plants of the moderately resistant tomato genotype King Kong 2 and the resistant genotype Hawaii 7998 grown in peat substrate. At 5 days post inoculation the bacterial population was significantly reduced in stems and roots of genotype Hawaii 7998, and in stems of King Kong 2 in silicon-treated plants compared to non-treated plants, indicating a silicon-induced resistance, since silicon accumulated in roots, but not in stems, while a tolerance effect was observed in the susceptible genotype L390. Characterization of possible molecular mechanisms involved in silicon-mediated resistance by immuno-histochemical analysis of stem cell walls indicated silicon-induced changes in the pectic polysaccharide structure. After infection homogalacturonan with non-blockwise degradation of methyl-esters was increased in vessel walls in non-silicon-treated plants, but not in silicon-treated plants, possibly indicating the action of pathogen pectinmethylesterase. Also the staining of vessel walls for arabinogalactan-protein in infected, non-silicon-treated plants was not observed in silicon-treated plants. In inoculated, silicon-treated plants, staining for arabinan side chains of rhamnogalacturonan I (RG I) was increased in some vessel walls, and fluorescence of antibodies for galactan side chains of RG I overall increased in the xylem parenchyma compared to non-silicon-amended plants. These observations suggest an induced basal resistance on cell wall level after silicon treatment, while the yellow or brown autofluorescence occurring in inoculated, non-silicon-treated plants disappeared. 相似文献
57.
Summary Field experiments with four potato cultivars showed that there were significant differences in susceptibility to attack by
wireworm,Agriotes obscurus. The two most susceptible cultivars had the lowest total glycoalkaloid (TGA) contents. Laboratory experiments with wireworms
feeding on tuber slices demonstrated that regions characterized by a low sugar and a high glycoalkaloid concentration were
avoided as feeding sites. Bio-assays with glycoalkaloids also showed that paper discs treated with a mixture of solanine and
chaconine were avoided by wireworms.
According to a forward stepwise regression analysis based on data from four cultivars and six regions of the tuber. TGA was
the key factor in predicting larval feeding, accounting for 65% of the total variation. Differences in reducing sugar levels
(fructose + glucose) explained an additional 13% of the variation. Differences in chlorogenic acid and sucrose levels added
very little to the accuracy of the prediction. 相似文献
58.
Rachidatou Sikirou Kerstin Wydra 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):939-947
The survival of Xanthomonas axonopodis pv. vignicola, incitant of cowpea bacterial blight and pustule, in residues of infested cowpea leaves was studied in the field in the forest savanna transition zone of South Benin and under variable controlled conditions. The pathogen survived for up to 60 days when placed on the soil surface, and up to 45 days buried at depths of 10 and 20 cm. In the glasshouse, bacteria survived in residue mixed with soil for at least 2 months in dry soil and less than 2 months in moist soil. The pathogen survived at least 30 days in the field after spray-inoculation on the weed species Euphorbia heterophylla, Digitaria horizontalis and Synedrella nodiflora; 20 days on Panicum subalbidum; 10 days on Euphorbia
hirta; and 5 days on Talinum triangulare. After leaf-infiltration under glasshouse conditions, the pathogen was detected after 90 days in D. horizontalis; 75 days in T.
triangulare, P. subalbidum and S. nodiflora; 60 days in E. hirta, and 30 days in E. heterophylla. Among 12 legume species tested as alternative hosts of X. axonopodis pv. vignicola, only Sphenostylis stenocarpa (African yam bean) showed typical symptoms of cowpea bacterial blight in a glasshouse experiment following artificial inoculation. This is the first time this legume species has been identified as a potential host of X. axonopodis pv.vignicola. Crop residue and weeds are likely sources of primary inoculum when planting two consecutive cowpea crops per year and they probably play a role in dissemination of the pathogen during the cropping season. The alternate host may form a bridge for primary inoculum between cropping seasons. 相似文献
59.
Genes for wheat stem rust resistance postulated in German cultivars and their efficacy in seedling and adult‐plant field tests 下载免费PDF全文
Kerstin Flath Thomas Miedaner Pablo D. Olivera Matthew N. Rouse Yue Jin 《Plant Breeding》2018,137(3):301-312
Stem rust of wheat (caused by Puccinia graminis f.sp. tritici) gained high international attention in the last two decades, but does not occur regularly in Germany. Motivated by a regional epidemic in 2013, we analysed 15 spring and 82 winter wheat cultivars registered in Germany for their resistance to stem rust at the seedling stage and tested 79 of these winter wheat cultivars at the adult‐plant stage. A total of five seedling stem rust resistance genes were postulated: Sr38 occurred most frequently (n = 29), followed by Sr31 (n = 11) and Sr24 (n = 8). Sr7a and Sr8a occurred only in two spring wheat genotypes each. Four cultivars had effective seedling resistance to all races evaluated that could only be explained by postulating additional resistance genes (‘Hyland’, ‘Pilgrim PZO’, ‘Tybalt’) or unidentified gene(s) (‘Memory’). The three winter wheat cultivars (‘Hyland’ ‘Memory’ and ‘Pilgrim PZO’) were also highly resistant at the adult‐plant stage; ‘Tybalt’ was not tested. Resistance genes Sr24 and Sr31 highly protected winter wheat cultivars from stem rust at the adult‐plant stage in the field. Disease responses of cultivars carrying Sr38 varied. Mean field stem rust severity of cultivars without postulated seedling resistance genes ranged from 2.71% to 41.51%, nine of which were significantly less diseased than the most susceptible cultivar. This suggests adult‐plant resistance to stem rust may be present in German wheat cultivars. 相似文献
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