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排序方式: 共有1789条查询结果,搜索用时 15 毫秒
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Gloria Lazzeri Carla L. Busceti Francesca Biagioni Cinzia Fabrizi Gabriele Morucci Filippo S. Giorgi Michela Ferrucci Paola Lenzi Stefano Puglisi-Allegra Francesco Fornai 《International journal of molecular sciences》2021,22(13)
Norepinephrine (NE) neurons and extracellular NE exert some protective effects against a variety of insults, including methamphetamine (Meth)-induced cell damage. The intimate mechanism of protection remains difficult to be analyzed in vivo. In fact, this may occur directly on target neurons or as the indirect consequence of NE-induced alterations in the activity of trans-synaptic loops. Therefore, to elude neuronal networks, which may contribute to these effects in vivo, the present study investigates whether NE still protects when directly applied to Meth-treated PC12 cells. Meth was selected based on its detrimental effects along various specific brain areas. The study shows that NE directly protects in vitro against Meth-induced cell damage. The present study indicates that such an effect fully depends on the activation of plasma membrane β2-adrenergic receptors (ARs). Evidence indicates that β2-ARs activation restores autophagy, which is impaired by Meth administration. This occurs via restoration of the autophagy flux and, as assessed by ultrastructural morphometry, by preventing the dissipation of microtubule-associated protein 1 light chain 3 (LC3) from autophagy vacuoles to the cytosol, which is produced instead during Meth toxicity. These findings may have an impact in a variety of degenerative conditions characterized by NE deficiency along with autophagy impairment. 相似文献
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Lucília Domingues Carla Oliveira Inês Castro Nelson Lima Jos A Teixeira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(8):809-815
Improved productivity and costs reduction in fermentation processes may be attained by using flocculating cell cultures. The production of extracellular heterologous β‐galactosidase by recombinant flocculating Saccharomyces cerevisiae cells, expressing the lacA gene (coding for β‐galactosidase) of Aspergillus niger under the ADHI promotor and terminator in a bioreactor was studied. The effects of lactose concentration and yeast extract concentration on β‐galactosidase production in a semi‐synthetic medium were analysed. The extracellular β‐galactosidase activity increased linearly with increasing initial lactose concentrations (5–150 g dm?3). β‐Galactosidase production also increased with increased yeast extract concentration. During the entire fermentation, no accumulation of the hydrolysed sugars, glucose and galactose, was observed. The catabolic repression of the recombinant strain when cultured in a medium containing equal amounts of glucose and galactose was confirmed. In complete anaerobiosis, the fermentation of lactose resulted in a very slow fermentation pattern with lower levels of β‐galactosidase activity. The bioreactor operation together with optimisation of culture conditions (lactose and yeast extract concentration) led to a 21‐fold increase in the extracellular β‐galactosidase activity produced when compared with preliminary Erlenmeyer fermentations. Copyright © 2004 Society of Chemical Industry 相似文献
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Semin Gün R.; Higgins Tory; de Montes Lorena Gil; Estourget Yvette; Valencia Jose F. 《Canadian Metallurgical Quarterly》2005,89(1):36
In 3 experiments, the authors investigated how strategic inclinations associated with promotion versus prevention orientations--that is, eager approach versus vigilant avoidance, respectively--affect the use of language. It is hypothesized that eager promotion strategies used to attain desired end states entail using more abstract language than used with vigilant prevention strategies. This is shown to hold for experimentally induced relationship goals (Experiment 1) and communication goals (Experiment 2). In the 3rd experiment, the authors examined the impact of abstractly and concretely worded messages upon the behavioral intentions of chronically prevention- and promotion-oriented individuals and found support for the hypothesis that behavioral intentions to engage in specific activities are stronger when there is a fit between message wording and chronic orientation than when there is no fit. The broader implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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This article describes the relationship between reading, phonological awareness abilities (PA), and intelligence in a group of 16 individuals with Williams syndrome (WS) and in a group of 16 typically developing children, matched for mental age. The individuals with WS were impaired in passage comprehension, in some areas of PA investigated (syllable deletion and rhyme detection), and in nonword reading accuracy, a measure of grapheme-phoneme conversion. This latter finding is relevant, considering that in Italy regular print-to-sound correspondence is the most practiced teaching routine in the early phases of learning to read. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献