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Green fluorescent protein (GFP)‐expressing transformants were used to investigate the effects of strobilurin fungicide azoxystrobin on Mycosphaerella graminicola infection. Azoxystrobin treatments (125 or 250 g AI ha?1) were applied at various stages of the infection process under controlled conditions. GFP transformants showed conserved in vitro sensitivity to azoxystrobin and pathogenicity. Azoxystrobin controlled over 90% of M graminicola infections when applied before or during penetration of the pathogen (15% of the incubation phase). Azoxystrobin also impaired the growth of intercellular hyphae in M graminicola post‐penetration infection stages when applied at up to 50% of the incubation phase. Incubating infections observed in treated leaves were viable, but their growth was impaired and they did not induce necrosis under controlled conditions. Reduction by half of azoxystrobin dosage had little or no effect on azoxystrobin efficiency in controlling M graminicola. The contribution of post‐penetration fungistatic effect to azoxystrobin curative properties toward M graminicola in a field situation is discussed. © 2001 Society of Chemical Industry  相似文献   
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The regulation of estrogen and progesterone receptor (ER, PR) expression by estradiol (E2) and progesterone (P4) in the oviduct, uterus and cervix of female lambs was studied. The animals received three intramuscular injections of E2, P4 or vehicle with an interval of 24 h and they were slaugthered 24 h after the third injection. Determinations of ER and PR were performed by binding assays and mRNAs of ER alpha and PR by solution hybridization. High levels of ER and PR in both cervix and oviduct were found in the female lamb, differing from other mammalian species. No significant effects by either E2 or P4 treatment on ER and PR levels in the cervix and oviduct could be observed. E2 treatment increased the mRNA levels of ERa and PR more than 3-fold in the cervix, while P4 treatment increased the mRNA levels of ERa and PR in the uterus. The results show differential effects of gonadal steroids on sex steroid receptor expression along the reproductive tract in female lambs, suggesting that steroid target tissues can modulate responses to the same circulating levels of steroid hormones.  相似文献   
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For investigations of CO2-stunning of feeder- and slaughter-pigs parameters of behaviour, blood-gas-analyses and electroencephalograms were chosen. The following results were obtained: 1. Blood-gas-analyses proved that the CO2-stunning does not produce unconsciousness due to a lack of oxygen. 2. The criterias of general anaesthesia: unconsciousness, muscle-relaxation and analgesia with total reversibility could be confirmed. 3. The violent convulsive symptoms were evaluated as reactions identical with the stage II of GUEDEL's scheme of anaesthesia. 4. Muscular agitation, which sometimes appeared a few seconds before the stage of excitation, was judged to belong either to the start of the excitation phase or to the end of Guedel's stage of analgesia, during which the sensitivity is decreased. Neither study of behavior nor objective measurements showed, during the first 10 to 20 seconds of exposure to the CO2, any sign of pain or suffering related to the Act for Prevention of Cruelty to Animals, and accordingly such suffering should not be ascribed to the CO2 stunning method.  相似文献   
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