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排序方式: 共有1210条查询结果,搜索用时 31 毫秒
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Inge Kronberg 《Helgoland Marine Research》1990,44(2):125-134
The adaptation of littorinid molluscs to prolonged aerial exposure was investigated by the determination of heat production.Littorina saxatilis, inhabiting the upper eulittoral, reached a maximum metabolic activity during submersion (heat production: 3.26×10−3J s−1 (gadw)−1. On the first three days of desiccation, the heat production was continuously reduced to 40% of the submersed value. A prolonged
aerial exposure was lethal for this species. In the supralittoralL. neritoides, three stages of energy metabolism could be observed: An intermediate heat production during submersion (1.97×10−3Js−1 (gadw)−1), an increased metabolism during the first hour of aerial exposure (heat production 204% of submersed value), and a minimal
metabolism (39% of the submersed value and 19% of maximum value) during the following days and weeks of desiccation. Recovery
depended on water salinity;L. saxatilis proved to be less euryhaline thanL. neritoides. Thus, the metabolic adaptations correlate with the level of littoral habitat; inactivity combined with a drastically reduced
energy consumption is a metabolically economic way to survive in periodically dry environments. 相似文献
3.
Inge N. Bojesen 《Prostaglandins & other lipid mediators》1985,30(3):479-489
The glycerolipid production by rat renal papillary slices varied inversely with the urea concentration (0a–1660 mM) whether the production was measured as labelling of the glycerol backbone from glucose or as incorporation of labelled arachidonic acid and palmitic acid. The rate of phospholipid formation was most dependent on medium urea concentrations in the range between 0 and 1100 mM. The production of prostaglandins PGE2 and PGF2α, measured radioimmunologically or by an isotope derivative method was in the same range inversely related to the production of glycerolipids and chain elongations. The effect of urea on prostaglandin formation is probably indirectly caused by the inhibition of the phospholipid formation and chain elongation, since the effect was abolished by 1% defatted albumin in the medium. The data suggest that the level of free arachidonic acid within the cells is controlled to an important extent by glycerolipid formation and chain elongation. 相似文献
4.
Jose R. Ernandes Tony D'Amore Inge Russell Graham G. Stewart 《Journal of industrial microbiology & biotechnology》1992,9(2):127-130
Summary Growth of yeast cells on glucose resulted in complete inactivation of maltose transport and repression of the high affinity glucose transport system. When the cells were grown on maltose or subjected to substrate starvation, an increase in glucose and maltose transport was observed in both brewing and non-brewing yeast strains. The concentration of glucose employed in the growth medium was also observed to affect sugar transport activity. The higher the glucose concentration, the more pronounced the repressive effect. In addition, the time of growth of yeast on glucose or maltose also intermining the rate of sugar transport. These results are consistent with the repressive effect of glucose on the high affinity glucose and maltose transport systems. 相似文献
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Idoia Labayen Jonatan R. Ruiz Inge Huybrechts Francisco B. Ortega Manuel Castillo Michael Sjöstrom Marcela González-Gross Yannis Manios Kurt Widhalm Anthony Kafatos Christina Breidenassel Gerardo Rodríguez Jean Dallongeville Frédéric Gottrand Luis A. Moreno 《Journal of physiology and biochemistry》2017,73(2):225-234
There is an increasing interest for the role of liver enzymes as predictors of non-liver-related morbidity and mortality. The American Heart Association (AHA) described the ideal cardiovascular health concept as a score of seven cardiovascular health behaviors and factors that can be used to monitor and predict ideal cardiovascular health over time. This study aimed to examine the association of the ideal cardiovascular health (ICH), as defined by the AHA, with liver enzyme levels in European adolescents. A total of 637 adolescents (54.6% females), aged 14.6 ± 1.2 years from nine European countries participated in this cross-sectional study. Blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase were measured and the AST/ALT ratio calculated. Ideal cardiovascular health was defined as meeting ideal levels of the following components: four behaviors (smoking, body mass index, physical activity, and diet) and three factors (total cholesterol, blood pressure, and glucose). A higher number of ideal cardiovascular health behaviors, factors, and ideal cardiovascular health index were associated with lower ALT (P < 0.05, P < 0.001, and P < 0.001, respectively) and gamma-glutamyltransferase (P < 0.001, P < 0.01, and P < 0.001, respectively) levels. Similarly, a higher number of ideal cardiovascular health behaviors (P < 0.01), factors (P < 0.01), and ideal cardiovascular health index (P < 0.001) were associated with a higher aspartate aminotransferase to alanine aminotransferase ratio. These findings reinforce the usefulness of the ICH index as an instrument to identify target individuals and promote cardiovascular health in adolescents, and it also extends these observations to the liver manifestation of the metabolic syndrome. 相似文献
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Inge Santman-Berends Saskia Luttikholt René Van den Brom Gerdien Van Schaik Maaike Gonggrijp Han Hage Piet Vellema 《PloS one》2014,9(8)
The aim of this study was to estimate the quantity of antibiotics and classes of antibiotics used in the small ruminant industry in the Netherlands in 2011 and 2012. Twelve large veterinary practices, located throughout the Netherlands were selected for this study. All small ruminant farms associated with these practices that had complete records on the quantity of antibiotics prescribed were included. The veterinary practices provided data on all antibiotics prescribed, and the estimated animal used daily dose of antibiotics per year (AUDD/Y) was calculated for each farm. The median AUDD/Y in small ruminant farms was zero in both years (mean 0.60 in 2011, and 0.62 in 2012). The largest quantity of antibiotic use was observed in the professional goat industry (herds of ≥32 goats) with a median AUDD/Y of 1.22 in 2011 and 0.73 in 2012. In the professional sheep industry (flocks of ≥32 sheep), the median AUDD/Y was 0 in 2011 and 0.10 in 2012. In the small scale industry (flocks or herds of <32 sheep or goats), the median AUDD/Y never exceeded 0. The most frequently prescribed antibiotics in the small scale industry and professional sheep farms belonged to the penicillin class. In professional goat farms, antibiotics of the aminoglycoside class were most frequently prescribed. This study provides the first assessment on the quantity of antibiotic use in the small ruminant industry. Given a comparable attitude towards antibiotic use, these results might be valid for small ruminant populations in other north-western European countries as well. The antibiotic use in the small ruminant industry appeared to be low, and is expected to play a minor role in the development of antibiotic resistance. Nevertheless, several major zoonotic bacterial pathogens are associated with the small ruminant industry, and it remains important that antibiotics are used in a prudent way. 相似文献
9.
BackgroundThe maturation cocktail composed of interleukin (IL)-6, IL-1β, tumor necrosis factor-α and prostaglandin E2 is considered the “gold standard” for inducing the maturation of dendritic cells (DCs) for use in cancer immunotherapy. Nevertheless, although this maturation cocktail induces increased expression of several activation markers, such as CD83, the co-stimulation molecules CD80, CD86 and CD40 and the chemokine receptor involved in DC homing in lymph nodes CCR7, the DC immune stimulatory function in vivo contrasts with this mature phenotype, and good clinical outcomes in patients with cancer treated with DC-based vaccines remain rare.MethodsPhenotypic characterization of the immunosuppressive status of DCs differentiated from peripheral blood mononuclear cells of healthy volunteers and matured with the “gold standard” cocktail was performed. Glucocorticoid-induced leucine zipper (GILZ) targeting small interfering RNA (siRNA) was electroporated into DCs after maturation to increase their immunogenicity.ResultsThe mature phenotype of DCs treated for 48 h with this cocktail was associated with the expression of several immunosuppressive regulators, including programmed cell death 1 ligand 1 (PD-L1), IL-10 and GILZ. Electroporation is a very efficient and safe way to deliver siRNA into DCs (80% of DCs receive at least one molecule of siRNA). Silencing GILZ in clinical-grade DCs by siRNA leads to a decrease of the PD-L1 expression associated with an increase in their IL-12 secretion and T-cell induction capability.ConclusionsGILZ silencing is a promising approach to achieving complete clinical-grade DC maturation and avoiding the immunosuppressive effects of the maturation cocktail on DCs intended for clinical use. 相似文献
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