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成百上千的活性物质正被用于人药和兽药处方中.由于药物的广泛应用,它们的残留物可通过多种途径进入环境.虽然主要通过尿和粪便的排泄,但是药品生产中的排放也应被考虑.当抗生素用于水产业,就会产生更直接的影响.污水处理设备不能完全除去药物,因此药物会出现在地表和地下水样品中.近年来,人们对环境中药物的兴趣正在增加,需要建立一种快速、灵敏、有选择性的方法来分析水样. 相似文献
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The olfactory circuitry of Drosophila melanogaster is becoming increasingly clear. However, how olfactory processing translates into appropriate behavioral responses is still
poorly understood. Using a sibling species approach, we tested how a perturbation in the olfactory circuitry affects odor
preference. In a previous study, we found that the sibling species of D. melanogaster, the specialist D. sechellia, overrepresents a sensillum, ab3, the A neuron of which is sensitive to hexanoate esters, characteristic of the species’
sole host, the Morinda citrifolia fruit. Concordantly, the corresponding glomerulus, DM2, is enlarged. In this study, we found that the ab3B neuron, the expansion
of which was previously assumed to be pleiotropic and of no ecological significance, is in fact tuned to another morinda fruit
volatile, 2-heptanone (HP). Axons of this neuron type arborize in a second enlarged glomerulus. In behavioral experiments
we tested how this has affected the fly’s odor preference. We demonstrate that D. sechellia has a reversed preference for the key ligands of these macroglomeruli, especially at high concentrations. Whereas D. melanogaster was repelled by high concentrations of these odors, D. sechellia was highly attracted. This was the case for odors presented singly, but more notably for blends thereof. Our study indicates
that relatively simple changes, such as a shift in sensillar abundance, and concordant shifts in glomerular size, can distort
the resulting olfactory code, and can lead to saltatory shifts in odor preference. D. sechellia has exploited this to align its olfactory preference with its ecological niche. 相似文献
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AL Heffernan K English LML Toms AM Calafat L Valentin-Blasini P Hobson S Broomhall RS Ware P Jagals PD Sly JF Mueller 《Environmental science and pollution research international》2016,23(23):23436-23448
A range of pesticides are available in Australia for use in agricultural and domestic settings to control pests, including organophosphate and pyrethroid insecticides, herbicides, and insect repellents, such as N,N-diethyl-meta-toluamide (DEET). The aim of this study was to provide a cost-effective preliminary assessment of background exposure to a range of pesticides among a convenience sample of Australian residents. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n = 24 pools of 100 specimens). Concentrations of urinary pesticide biomarkers were quantified using solid-phase extraction coupled with isotope dilution high-performance liquid chromatography–tandem mass spectrometry. Geometric mean biomarker concentrations ranged from <0.1 to 36.8 ng/mL for organophosphate insecticides, <0.1 to 5.5 ng/mL for pyrethroid insecticides, and <0.1 to 8.51 ng/mL for all other biomarkers with the exception of the DEET metabolite 3-diethylcarbamoyl benzoic acid (4.23 to 850 ng/mL). We observed no association between age and concentration for most biomarkers measured but noted a “U-shaped” trend for five organophosphate metabolites, with the highest concentrations observed in the youngest and oldest age strata, perhaps related to age-specific differences in behavior or physiology. The fact that concentrations of specific and non-specific metabolites of the organophosphate insecticide chlorpyrifos were higher than reported in USA and Canada may relate to differences in registered applications among countries. Additional biomonitoring programs of the general population and focusing on vulnerable populations would improve the exposure assessment and the monitoring of temporal exposure trends as usage patterns of pesticide products in Australia change over time. 相似文献
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Simone Poddighe Teun Dekker Antonio Scala Anna Maria Angioy 《Die Naturwissenschaften》2010,97(9):827-835
The nasal botfly Oestrus ovis (Diptera, Cyclorrhapha: Oestridae) is a myiasis-causing insect species, which affects the health of sheep, goats and humans.
Gravid females are viviparous and larviposit into the animal’s nostrils. Host-searching and larvipositing flies are visually
guided and influenced by climatic conditions, whereas olfaction seemed to play no role in this process. However, here, we
show that the antennae of adult O. ovis female flies are relatively small but well developed and inhabited by several types of olfactory sensilla. Further, we show
that the antennal lobes of this species receive input from antennal afferents and consist of a clearly defined glomerular
organisation. We also give the first evidence of the fly’s ability to detect several synthetic odour compounds. Our findings
provide a morpho-functional basis for future investigations on olfactory-mediated behaviour of this insect pest. 相似文献
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