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21.
Pro-pesticides of alpha-(2,6-dichloro-4-trifluoromethylphenylhydrazono)-4-nitrophenylacetonitrile have been prepared and tested against mite and insect pests. Variations in potency and spectrum were observed depending on the choice of cleavable pro-moiety. Cleavage of the pro-moiety was demonstrated in one case by measuring the rate of increase in the uncoupling activity using a mitochondrial preparation. Irradiation experiments have demonstrated a rapid isomerisation of the planar Z isomer to the E isomer, which is reversible.  相似文献   
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Experiments on nitrogen immobilization in minerally fertilized soils from loess during the growing season of winter wheat The nitrogen regime has been simulated during the growing period of winter wheat 1984/85 on a stagnigleyic cambisol using a simple, functional computer model. The model includes N mineralization from soil organic matter, transport of water and nitrate as well as growth of wheat and N uptake by the crop. Simulation starts at harvest of the previous crop. Simulated and measured N supply (soil mineral nitrogen plus N uptake by the plant) were in good agreement between september and december 1984. On this loess plot as well as on 10 other ones an over-estimation of mineral nitrogen in the soil up to 40 kg/ha was observed with beginning of december/january 1984/85 reflecting a seasonal trend. Experiments with 15N enriched Ca-nitrate 1984/85 on microplots of the same field point to a non-consideration of nitrogen immobilization. Fertilizer-N-immobilization amounted up to 35 kg/ha in the soil and to further 15 kg/ha in the straw material. The pool of fixed ammonium was of no importance with respect to the mobilization-immobilization-turn-over of fertilizer nitrogen. Experiments 1988/89 on microplots of a colluvial loess soil indicate a change of biomass nitrogen being responsible for the seasonal N-immobilization. An increase of biomass-N of about 30 kg/ha was observed under the growing wheat crop. An additional N-immobilization of nearly 40 kg/ha was observed with straw incorporation. A similar increase of microbial biomass nitrogen under winter wheat has been observed during the growing period 1987/88.  相似文献   
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Summary Dendranthema grandiflora Tzvelev (Chrysanthemum morifolium Ramat.) garden cultivars Vulcan, with deep red ray florest, and Superior, with orange ray petals, were crossed as female with 16 inbred clones and the progeny assessed visually for flower color in 3 environments. Intensity of vacuole pigmentation in ray florets appeared to vary continuously. Evaluation was facilitated by placing plants in 7 color classes ranging from red, the most intense, through orange, an intermediate intensity, to yellow, the apparent lack of vacuole pigmentation. A simple hexaploid model with additive gene action, suggested by the 7 color classes, was inappropriate, as more than 50% of the plants in Vulcan families were red and more than 60% of the plants in Superior families were orange. Comparing evaluations of parental clones in 2 glasshouse and 2 field environments and considering data from an experiment, in which progeny first classified in the glasshouse were reevaluated in the field, revealed substantial shifts in classification. In the glasshouse, more individuals appeared in the red and orange classes, while field evaluation placed more individuals in classes adjacent to red and orange. However, the predominance of progeny in the color class of the common parent, that is, red for the Vulcan and orange for the Superior families, occurred in both glasshouse and field. Plants scored as other than red appeared in crosses between Vulcan and 3 red inbreds, suggesting that red ray petals are not conditioned by a homozygous genotype. The orange of Superior and orange progeny may be due to a single dominant gene causing mosaic-like distribution of red vacuole pigmentation over yellow plastid pigmentation. Because cloned genotypes were classified differently in diverse environments, critical genetic analysis of vacuole pigmentation will require cloned progeny and multiple-environment evaluation.  相似文献   
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Summary Four glasshouse and 13 garden chrysanthemum cultivars or inbred seedlings from the color groups white, yellow, pink/purple, and orange/red/bronze were analyzed with thin-layer chromatography (TLC) for qualitative and quantitative pigment constituents. TLC confirmed the presence of eight carotenoids in yellow and bronze cultivars. Qualitative differences exised only for spots 5–8. Rf values for lutein matched those of spot 4. Flavonoid analysis of purples and bronzes revealed two anthocyanidins, one of which was cyanidin, one flavone, and two phenylpropanoids. White cultivars had four phenylpropanoids, two of which were caffeic and ferulic acids. In most cases, inbred and non-inbred cultivars within a given phenotypic class did not exhibit qualitative differences. Color analysis could be pursued at any level of inbreeding, but inheritance studies would be severely hampered using non-inbred genotypes of this hexaploid floricultural crop.  相似文献   
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This article focuses on the principles involved in making radiographs of equine limbs; understanding radiographic anatomy, including normal variations; and principles of radiographic interpretation. The influence of pathogenesis of disease on the radiographic image is considered. Diseases associated with racing as well as the developing racehorse are discussed.  相似文献   
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In vitro studies have shown that cytokines are involved in the regulation of the immune response, but their role in vivo is less well defined. Specific cytokine antagonists enable the identification of particular cytokines involved in the response and offer a means for modifying it. Systemic administration of a soluble, extracellular portion of the receptor for interleukin-1 (sIL-1R) had profound inhibitory effects on the development of in vivo alloreactivity. Survival of heterotopic heart allografts was prolonged from 12 days in controls to 17 days in mice treated with sIL-1R. Lymph node hyperplasia in response to a localized injection of allogeneic cells was completely blocked by sIL-1R treatment. The inhibition was overcome by simultaneous administration of interleukin-1 (IL-1); thus, sIL-1R acts by neutralizing IL-1. These results implicate IL-1 as a regulator of allograft rejection and demonstrate the in vivo biological efficacy of a soluble cytokine receptor.  相似文献   
30.
Fifteen novel microsatellite markers were isolated from Fusarium graminearum. The level of polymorphism at these novel and 13 previously published microsatellite markers was analysed in 33 F. graminearum strains from Europe, North America, and Nepal. The number of alleles for each of the novel markers ranged from 4 to 20 and gene diversity from 0.417 to 0.962. In comparison with the previously published markers, the resolution for distinguishing among different strains was slightly increased. Twenty-seven markers were also detectable in three F. culmorum strains and one F. crookwellense strain. None of the markers was detected in three F. avenaceum and four F. poae strains, underlining the potential use of these microsatellite markers for species differentiation.  相似文献   
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