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Lappin MR Griffin B Brunt J Riley A Burney D Hawley J Brewer MM Jensen WA 《Journal of Feline Medicine and Surgery》2006,8(2):85-90
Ctenocephalides felis were killed and collected from 92 cats in Alabama, Maryland, and Texas. The fleas and blood from the corresponding cat were digested and assessed in polymerase chain reaction assays that amplify DNA of Ehrlichia species, Anaplasma phagocytophilum, Neorickettsia risticii, Mycoplasma haemofelis, 'Candidatus M haemominutum' and Bartonella species. DNA consistent with B henselae, B clarridgeiae, M haemofelis, or 'Candidatus M haemominutum' was commonly amplified from cats (60.9%) and their fleas (65.2%). Results of this study support the recommendation to maintain flea control on cats in endemic areas. 相似文献
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Among contact fungicides, dithiocarbamates have remained successful and are used worldwide. These organic sulfur fungicides, viz. mancozeb, maneb, zineb, ziram, thiram, metiram and propineb, have helped growers manage several economically important plant diseases. Their multi‐site mode of action and broad‐spectrum disease control make them some of the most common partners in mixtures of a number of single‐site fungicides as part of resistance management strategies. Indeed, it was the part played by ethylene‐bis‐dithiocarbamates such as mancozeb in delaying the evolution of phenylamide resistance in several oomycete phytopathogens that laid the groundwork for mixture strategies to become a cornerstone of anti‐resistance management in plant disease control. Dithiocarbamates, however, do not have systemic action, are only surface protectants and have to be applied prior to pathogen infection. Dithiocarbamates will likely continue play a key role as reliable resistance management tools to prolong the efficacy of single‐site fungicides. The primary metabolite ethylene thiourea produced by some of these fungicides is considered a reproductive and endocrine disrupter in animals. Therefore, dithiocarbamates need to be used at reduced rates or in slow‐release formulations. © 2017 Society of Chemical Industry 相似文献
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The optimisation of plant nitrogen-use-efficiency (NUE) has a direct impact on increasing crop production by optimising use of nitrogen fertiliser. Moreover, it protects environment from negative effects of nitrate leaching and nitrous oxide production. Accordingly, nitrogen (N) management in agriculture systems has been major focus of many researchers. Improvement of NUE can be achieved through several methods including more accurate measurement of foliar N contents of crops during different growth phases. There are two types of methods to diagnose foliar N status: destructive and non-destructive. Destructive methods are expensive and time-consuming, as they require tissue sampling and subsequent laboratory analysis. Thus, many farmers find destructive methods to be less attractive. Non-destructive methods are rapid and less expensive but are usually less accurate. Accordingly, improving the accuracy of non-destructive N estimations has become a common goal of many researchers, and various methods varying in complexity and optimality have been proposed for this purpose. This paper reviews various commonly used non-destructive methods for estimating foliar N status of plants. 相似文献