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991.
Navarrete-Casas M Segura-Carretero A Cruces-Blanco C Fernández-Gutiérrez A 《Pest management science》2005,61(2):197-203
We describe a detailed study on the possibility of analyzing aminated pesticides and metabolites using pre-column derivatization with fluorescein isothiocyanate (FITC) and their subsequent separation and detection by cyclodextrin capillary electrophoresis-laser-induced fluorescence (CE-LIF) detection. Different variables affecting the derivatization reaction (pH, FITC concentration, reaction time and temperature) and those related with the separation itself (buffer concentration, addition of various organic modifiers, pH, applied voltage and injection time) were studied. The limit of detection obtained was between 0.45 and 3.48 microg litre(-1) showing a relative standard deviation between 0.26 and 2.08% at a concentration level of 50 microg litre(-1). 相似文献
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A Fernández J Martín de las Mulas M A Sierra J Carranza A Jover 《DTW. Deutsche tier?rztliche Wochenschrift》1989,96(4):192-194
Indirect Immunoperoxidase (IIP) and Avidin Biotin-Peroxidase Complex (ABC) techniques were used for the detection of Infectious Bursal Virus (IBV) and Marek Disease Virus (MDV) antigens in alcohol and formalin-fixed, paraffin-embedded lymphoid tissues from broilers. Both techniques appeared potentially useful for the diagnosis of both viral antigens in alcohol-fixed tissues, and allowed the observation of dual infection in the bursa of Fabricius of the studied animals in a natural infection. 相似文献
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A Fernández M Quezada M A Gómez J A Navarro J Rodríguez M A Sierra 《Avian diseases》1990,34(1):224-227
Cryptosporidiosis in chickens from southern Spain is reported. Cryptosporidia were found in the trachea, esophagus, and epithelium of the bursa of Fabricius in chickens from different regions. In one flock, cryptosporidiosis was associated with respiratory problems and high mortality. In another flock, it was associated with low mortality and weight loss. 相似文献
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Carabid beetle assemblages (Coleoptera,Carabidae) across urban-rural gradients: an international comparison 总被引:14,自引:0,他引:14
Niemelä Jari Kotze D. Johan Venn Stephen Penev Lyubomir Stoyanov Ivailo Spence John Hartley Dustin de Oca Enrique Montes 《Landscape Ecology》2002,17(5):387-401
We studied communities of carabid beetles in residual forest patchesalong urban-suburban-rural gradients in three cities (Helsinki, Finland; Sofia,Bulgaria and Edmonton, Canada) to examine their responses to urbanisation. OnlyFinnish carabids showed a marked division of community structure along thegradient. In Bulgaria and Canada, carabids did not separate into distincturban,suburban and rural communities. Our results provide some support for thepredictions that species richness will decrease, that opportunistic specieswillgain dominance, and that small-sized species will become more numerous underdisturbance such as that provided by urbanisation. The rather weak and variedresponse of carabids to this disturbance suggests that local factors and theirinteraction are of primary importance for community composition. Occurrence ofreasonably similar carabid communities across the gradient at each of the threelevels of urbanisation suggests that habitat changes commonly associated withurbanisation have not affected the ecological integrity of carabid assemblagesin residual urban forest patches.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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