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排序方式: 共有490条查询结果,搜索用时 343 毫秒
481.
M V Ayudarte M C Nu?ez J Boza J Jimenez A Gil M D Suarez 《Comparative biochemistry and physiology. B, Comparative biochemistry》1992,103(1):65-69
1. Dietary orotate produced a decrease in total plasma fatty acids which was reflected in low values of saturated, monounsaturated and polyunsaturated fatty acids longer than 18 carbon atoms of the n-6 series. The relative content of saturated fatty acids in microsomes of animals fed orotate was also decreased. 2. Rat liver delta-9 desaturase activity was lower in the group fed orotate. However, delta-6 desaturase activity did not show significant differences between the groups. 3. Microsomal cholesterol content was lower in rats fed orotate than in controls but phospholipid phosphorus contents were similar. These results suggest a direct effect of dietary orotate on the key enzymes which regulates cholesterol liver metabolism. 相似文献
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Daniela Sarmiento Alvaro Becerra Felipe Nuñez‐Villena Xavier F. Figueroa Claudio Cabello‐Verrugio Alvaro A. Elorza Claudia Riedel Felipe Simon 《Journal of cellular and molecular medicine》2013,17(6):800-814
Endothelial dysfunction is crucial in endotoxaemia‐derived sepsis syndrome pathogenesis. It is well accepted that lipopolysaccharide (LPS) induces endothelial dysfunction through immune system activation. However, LPS can also directly generate actions in endothelial cells (ECs) in the absence of participation by immune cells. Although interactions between LPS and ECs evoke endothelial death, a significant portion of ECs are resistant to LPS challenge. However, the mechanism that confers endothelial resistance to LPS is not known. LPS‐resistant ECs exhibit a fibroblast‐like morphology, suggesting that these ECs enter a fibrotic programme in response to LPS. Thus, our aim was to investigate whether LPS is able to induce endothelial fibrosis in the absence of immune cells and explore the underlying mechanism. Using primary cultures of ECs and culturing intact blood vessels, we demonstrated that LPS is a crucial factor to induce endothelial fibrosis. We demonstrated that LPS was able and sufficient to promote endothelial fibrosis, in the absence of immune cells through an activin receptor–like kinase 5 (ALK5) activity–dependent mechanism. LPS‐challenged ECs showed an up‐regulation of both fibroblast‐specific protein expression and extracellular matrix proteins secretion, as well as a down‐regulation of endothelial markers. These results demonstrate that LPS is a crucial factor in inducing endothelial fibrosis in the absence of immune cells through an ALK5‐dependent mechanism. It is noteworthy that LPS‐induced endothelial fibrosis perpetuates endothelial dysfunction as a maladaptive process rather than a survival mechanism for protection against LPS. These findings are useful in improving current treatment against endotoxaemia‐derived sepsis syndrome and other inflammatory diseases. 相似文献
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Nunu Huang Fanying Li Maolei Zhang Huangkai Zhou Zhipeng Chen Xiaoyan Ma Lixuan Yang Xujia Wu Jian Zhong Feizhe Xiao Xuesong Yang Kun Zhao Xixi Li Xin Xia Zexian Liu Song Gao Nu Zhang 《Cell metabolism》2021,33(1):128-144.e9
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Nuñez Martin A. Chiuffo Mariana C. Seebens Hanno Kuebbing Sara McCary Matthew A. Lieurance Deah Zhang Bo Simberloff Daniel Meyerson Laura A. 《Biological invasions》2022,24(2):333-340
Biological Invasions - Most published papers in ecology come from a handful of countries, and invasion science as an ecological subdiscipline is no exception. Based on the country of corresponding... 相似文献
488.
Staphylococcus aureus, thermostable nuclease and staphylococcal enterotoxins in raw ewes' milk Manchego cheese 总被引:1,自引:0,他引:1
Growth and survival of two enterotoxigenic strains of Staphylococcus aureus were studied during manufacture and ripening of eight batches of raw ewes' milk Manchego cheese. Only 2-3 generations of Staph. aureus occurred in the vat and during pressing. The death rate of Staph. aureus (mean decrease in log cfu/g/week of ripening) from day 1 to day 60 was 0.421 in cheese made with 1% Streptococcus lactis starter and 0.404 in cheese made without starter. Thermostable nuclease was produced in the vat by growing Staph. aureus cells; it was inactivated by rennet during the first 24 h and synthesized again by surviving cells of Staph. aureus from day 1 to day 60. Staphylococcal enterotoxins A, B, C and D were not detected in any batches of cheese, even though Staph. aureus counts exceeded 10(7) cfu/g. 相似文献
489.
Moreira Marrero Lucía Botto Nuñez Germán Malta Lucía Delfraro Adriana Frabasile Sandra 《EcoHealth》2021,18(1):123-133
EcoHealth - Bats are the second most diverse order of mammals and key species for ecosystem functioning, providing a wide range of ecosystem services, from pest control to seed dispersal.... 相似文献
490.
Milton H. Gallardo Elkin Y. Suárez‐Villota José J. Nuñez Rodrigo A. Vargas Ronie Haro Nélida Köhler 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(2):453-469
The allotetraploid Tympanoctomys barrerae has a broad, patchy distribution around salt flats in western Argentina. To gain insights into its phylogenetic relationships, phylogeographical patterns, and origin, seven populations of T. barrerae and its allied taxa were studied through a 1075‐bp fragment of cytochrome b and cytochrome oxidase I. Matrilineal phylogenetic relationships were explored with maximum likelihood and Bayesian approaches. The intraspecific genealogy was inferred by median‐joining networks. The populational structure was assessed by molecular variance, and the demographic history through coalescence. The tree topology depicted sister‐group relationship between Octomys mimax to the pair T. barrerae–Pipanacoctomys aureus, suggesting P. aureus belongs to the maternal lineage that gave rise to T. barrerae. High degrees of intrapopulational variation and the several instances of interpopulational polyphyly suggest range shifts and secondary contact. Consistent with the phylogenetic results, the network analysis revealed two haplotypic lineages depicting genetic admixtures unrelated to the current geographical distribution, and a deep split with the southernmost lineage of Chubut. The origin of T barrerae was estimated at approximately 2.52 Mya, whereas the divergence estimate for Chubut coincides with the end of largest Patagonian glaciation, at 1.47 Mya. Apparently, this population remained isolated during a northward Pleistocenic range shift. The historical demographic patterns of the lineages of T. barrerae fit with a contraction–expansion model coincident with Quaternary cycling events. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 108 , 453–469. 相似文献