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Contradictory evidence as to the effects of alcohol on early information processing stages has been obtained from behavioral and psychophysiological investigations. In the present study, choice reaction times, error rates, and event-related potentials (ERPs) were recorded in a task in which variations in stimulus discriminability and of the (task irrelevant) correspondence between stimulus location and response location were orthogonally combined. Both discriminability and stimulus-response correspondence affected reaction time and electrophysiological chronometric measures as expected. However, no behavioral effects of alcohol were observed, possibly because of strategic adjustments. Psychophysiological chronometric measures indicated that alcohol leaves the initial flow of perceptual evidence to motor stages unimpaired, whereas it appears to increase the duration of stimulus evaluation. Interestingly, a number of alcohol effects appeared in the ERP amplitudes. Decrements in early ERP components indicate alcohol-induced impairments of involuntary visual attention and/or the automatic stimulus location-dependent activation of response channels. In contrast, a strong enhancement of a late slow-wave component under alcohol may reflect the investment of processing resources in order to maintain normal performance levels.  相似文献   
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The effectiveness ofLeucaena leucocephala (Lam.) de Wit, prunings as N source for maize (Zea mays L.) was evaluated in field and pot trials at Ibadan, southern Nigeria. An N deficient, sandy Apomu soil (Psammentic Usthorthent) was used. The prunings significantly increased N uptake of seedlings and N percentage in ear leaves of maize. High maize gain yield was obtained with application of 10 tons fresh prunings or a combination of 5 tons fresh prunings and N at 50 kg ha–1. The prunings as N source, appeared to be more effective when incorporated in the soil than when applied as mulch. In the pot trial, prunings applied two weeks before planting was more effective than when applied at time of planting maize. Under screen house conditions, the apparent N recovery from prunings with early incorporation about equals that of fertilizer N.  相似文献   
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The cell-wall characteristics of Gardnerella vaginalis grown in conventional and biofilm systems were studied by electron microscopy. The gram-positive nature of the cell wall was confirmed. Novel cell-wall particles which appeared to be associated with cell division were also identified, particularly in organisms of biofilm origin.  相似文献   
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A diffusion cell with an artificial membrane and the single-pass perfused rabbit ear were used to evaluate the percutaneous absorption of clonazepam from various 2-hydroxyethyl acetate (HEA) patches. The influence on drug permeation of the various type of enhancers (isopropylmyristate, lauryl alcohol, propylene glycol and water) in the patches was tested. A comparison between the two types of systems of percutaneous absorption of clonazepam has been done. The results showed that HEA patches produce controlled uniform drug release, modulated by the addition of enhancers.  相似文献   
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