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Andrea Schneider Manuela Ruppert Oliver Hendrich Thomas Giang Maite Ogueta Stefanie Hampel Marvin Vollbach Ansgar Büschges Henrike Scholz 《PloS one》2012,7(12)
The decision to move towards a mating partner or a food source is essential for life. The mechanisms underlying these behaviors are not well understood. Here, we investigated the role of octopamine – the invertebrate analogue of noradrenaline – in innate olfactory attraction to ethanol. We confirmed that preference is caused via an olfactory stimulus by dissecting the function of the olfactory co-receptor Orco (formally known as OR83b). Orco function is not required for ethanol recognition per se, however it plays a role in context dependent recognition of ethanol. Odor-evoked ethanol preference requires the function of Tbh (Tyramine β hydroxalyse), the rate-limiting enzyme of octopamine synthesis. In addition, neuronal activity in a subset of octopaminergic neurons is necessary for olfactory ethanol preference. Notably, a specific neuronal activation pattern of tyraminergic/octopaminergic neurons elicit preference and is therefore sufficient to induce preference. In contrast, dopamine dependent increase in locomotor activity is not sufficient for olfactory ethanol preference. Consistent with the role of noradrenaline in mammalian drug induced rewards, we provide evidence that in adult Drosophila the octopaminergic neurotransmitter functions as a reinforcer and that the molecular dissection of the innate attraction to ethanol uncovers the basic properties of a response selection system. 相似文献
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Oliver Goldschmidt Jonathan F. Bard Alexan Takvorian 《Flexible Services and Manufacturing Journal》1997,9(3):251-272
Mixed-model assembly lines are becoming increasingly interesting as the use of just-in-time principles in manufacturing continues to expand. This paper presents, for the first time, complexity results for the underlying problem of product sequencing. It is shown that the problem is intractable for both the single station and the multiple station case. Nevertheless, efficient 1.5-approximation algorithms are developed for the early- and late-start models associated with the former case. Empirical results demonstrate that these algorithms perform extremely well in practice. 相似文献
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A Dutour P Giraud C Kowalski L Ouafik P Salers V Strbak C Oliver 《Biochemical and biophysical research communications》1987,146(1):354-360
The rapid changes in TRH levels in the rat pancreas during the neonatal period make this organ an interesting model for the study of the regulation of TRH biosynthesis. Pancreatic RNAs were isolated by the guanidinium thiocyanate method and layered onto CsCl cushion. Northern blot preparations were hybridized with 32P labeled TRH cDNA probe. Pancreatic TRH mRNA was first detected in 19-day old fetuses and reached the highest level on day 0, then decreased, being barely detectable 14 days after birth. The neonatal injection of streptozotocin induced a dramatic drop of TRH mRNA levels 24 hours later. This result suggests that the peculiar evolution of TRH level in pancreas is partly due to the evolution of the expression of the TRH gene. 相似文献
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Oliver M. Brown 《Life sciences》1981,28(7):819-825
The distribution of acetylcholine (ACh) in the cat heart was investigated by pyrolysis-gas chromatography (PGC) and pyrolysis-mass fragmentography (PMF) techniques. The hearts were dissected into various regions and homogenized in the presence of butyrycholine (or propionylcholine) as internal standard. The choline esters were isolated and analyzed by PGC or by PMF (at m/e 58). A pattern of distribution for ACh was found to be the same as I have previously described (1,2). Some cats were subjected to either a right or a left unilateral cervical vagotomy 4 weeks before removal and analysis of heart tissue. Hearts from unilateral (right or left) vagotomized cats did not differ from controls in the ACh content of any heart area examined. These results are consistent with the idea that intact parasympathetic neurons may compensate for the denervation following unilateral vagotomy. 相似文献
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Margarita Burguera-Pascu Alberto Rodríguez-Archilla Pilar Baca 《Journal of trace elements in medicine and biology》2007,21(2):92-101
The antimicrobial efficacy of zinc (Zn) salts (sulfate and acetate) against Streptococcus mutans (S. mutans) present in the oral cavity was tested in this study. The substantivity of Zn salts was assessed by determining the concentration of Zn in whole, unstimulated saliva and by measuring the magnitude of suppression of salivary S. mutans, 2h after rinsing. The concentration of Zn was measured by atomic absorption spectrometry (AAS) with electrothermal atomization (ET AAS) in saliva sampled before (basal) and 24h after mouth rinsing with different concentrations of Zn (0.1%, 0.5% and 1%) administrated as sulfate and acetate. The estimation of Zn levels in samples collected 30, 60, 90 and 120 min after rinsing was carried out by AAS with flame atomization (FAAS). Immediately after rinsing, the concentration of Zn in saliva sharply increased with respect to the baseline values (0.055+/-0.017 mg/L), followed by a sustained decrease, probably due to clearance of salivary flow or swallowing during sampling. A significant reduction (>87%) in the total mean S. mutans counts was found 2h after rinsing either with sulfate or acetate solutions, as evidence of the high substantivity and effectiveness of the Zn salts tested. A statistically significant inverse relationship (p<0.001 and the Pearson correlation coefficients between -34% and -50%) was found between Zn levels and the respective pH values measured in the samples collected 60 and 120 min after rinsing, sustaining the theory of bacterial glycolysis inhibition. 相似文献
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The postnatal induction of serine dehydratase in rat liver 总被引:4,自引:0,他引:4