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排序方式: 共有992条查询结果,搜索用时 15 毫秒
1.
Antoni Sicras-Mainar Javier Rejas Ruth Navarro Milagrosa Blanca Ángela Morcillo Raquel Larios Soledad Velasco Carme Villarroya 《Arthritis research & therapy》2009,11(2):R54-14
Introduction
The objective of this study was to analyze health care and non-health care resource utilization under routine medical practice in a primary care setting claims database and to estimate the incremental average cost per patient per year of fibromyalgia syndrome (FMS) compared with a reference population. 相似文献2.
Mireia Medrano David Aguinaga Irene Reyes-Resina Enric I. Canela Josefa Mallol Gemma Navarro Rafael Franco 《Molecular neurobiology》2018,55(6):4718-4730
The hypothalamus is a key integrator of nutrient-seeking signals in the form of hormones and metabolites originated in both the central nervous system and the periphery. The main autocrine and paracrine target of orexinergic-related hormones such as leptin, orexin/hypocretin, and ghrelin are neuropeptide Y neurons located in the arcuate nucleus of the hypothalamus. The aim of this study was to investigate the expression and the molecular and functional relationships between leptin, orexin/hypocretin and ghrelin receptors. Biophysical studies in a heterologous system showed physical interactions between them, with potential formation of heterotrimeric complexes. Functional assays showed robust allosteric interactions particularly different when the three receptors are expressed together. Further biochemical and pharmacological assays provided evidence of heterotrimer functional expression in primary cultures of hypothalamic neurons. These findings constitute evidence of close relationships in the action of the three hormones already starting at the receptor level in hypothalamic cells. 相似文献
3.
Halobacterial megaplasmids are negatively supercoiled 总被引:1,自引:0,他引:1
Purificación López-García Josefa Antón Jose Pascua Abad Ricardo Amils 《Molecular microbiology》1994,11(3):421-427
Several covalently closed circular halobacterial megaplasmids (up to more than 500 kb) from different strains of Halolerax mediterranei, have been resolved by orthogonal-field alternating gel electro-phoresis (OFAGE). These molecules seem to be negatively supercoiled in vivo, as deduced from the effect of intercalating agents affecting their topology and, therefore, their electrophoretic mobility. It has also been demonstrated that the topolsomerase II Inhibitor novobiocin affects the native topological state of halobacterial megaplasmids impeding their migration in OFAGE under standard conditions for resolution of large supercoiled molecules. 相似文献
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Josefa Bleu Anne Loison Carole Toïgo 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(2):516-521
Life‐history theory predicts trade‐offs in energy allocation between different life‐history traits when resources are limited, i.e. certain traits should be negatively correlated. However, individuals differ in their ability to acquire resources, which can lead to positive correlations between traits at the population level. Here, we investigated the consequences of the allocation in horn growth and body mass on survival in a bovid (Rupicapra rupicapra) with capture‐mark re‐sighting data on 161 females. In female ungulates, body mass often covaries positively with demographic performance and the few studies on horn size suggest that this trait could be a signal of individual quality. Thus, we expected to measure positive correlations between the allocation in these traits and female survival. However, body mass was not correlated to female survival and there was only a negative, though marginal, effect of horn growth. Hence, it seems that the allocation in growth is not an indicator of female quality. Future studies could investigate the importance of growth on female reproduction to evaluate its effect on lifetime reproductive success. Moreover, it is important to confirm in other populations our result that suggests a cost of the allocation in horn growth to better understand the presence of horns in female bovids. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 516–521. 相似文献
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Acceptor-donor relationships in the transglutaminase-mediated cross-linking of lens beta-crystallin subunits 总被引:4,自引:0,他引:4
Following the isolation of the N epsilon-(gamma-glutamyl)lysine-containing polymers from human cataracts, our efforts were directed to induce such cross-links experimentally in rabbit lens, and evidence was obtained for the selective reactivities of certain beta-crystallin subunits in this transglutaminase-catalyzed event. In the present work, we examined the enzymatic cross-linking of purified crystallins individually (alpha, beta H, beta L, and gamma) and in combinations, with particular emphasis on forming the approximately 55K dimer. This species was the primary product in the cross-linking of beta H-crystallins; beta L also reacted with transglutaminase. Neither alpha- nor gamma-crystallins formed appreciable amounts of cross-linked structures with transglutaminase. Dansylcadaverine, known to compete against the reactive lysines of proteins in forming N epsilon-(gamma-glutamyl)lysine cross-bridges, was shown to inhibit the generation of dimeric and higher ordered oligomers from beta H and beta L. The fluorescent amine specifically labeled only two subunits in beta H (approximately 29-30K and approximately 26K) and one in beta L (approximately 26K), identifying these substrates as possessing transglutaminase-reactive endo-gamma-glutaminyl residues. An antiserum to bovine beta Bp recognized the approximately 23K subunit of rabbit beta-crystallins and also the approximately 55K dimer, suggesting that the approximately 23K protein participates as a lysine donor in generating the cross-linked dimer with transglutaminase. Inasmuch as the same antiserum reacts with an approximately 50K material reported to appear in increasing amounts with age in human lens, the results lend added support to the physiological significance of transglutaminase in the aging of lens. 相似文献
9.
Paula Arribas Josefa Velasco Pedro Abellán David Sánchez‐Fernández Carmelo Andújar Piero Calosi Andrés Millán Ignacio Ribera David T. Bilton 《Journal of Biogeography》2012,39(5):984-994
Aim In aquatic ecosystems, standing (lentic) and running (lotic) waters differ fundamentally in their stability and persistence, shaping the comparative population genetic structure, geographical range size and speciation rates of lentic versus lotic lineages. While the drivers of this pattern remain incompletely understood, the suite of traits making up the ability of a species to establish new populations is instrumental in determining such differences. Here we explore the degree to which the association between habitat type and geographical range size results from differences in dispersal ability or fundamental niche breadth in the members of the Enochrus bicolor complex, an aquatic beetle clade with species across the lentic–lotic divide. Location Western Mediterranean, with a special focus on North Africa, the Iberian Peninsula and Sicily. Methods DNA sequences for four loci were obtained from species of the E. bicolor complex and analysed using phylogenetic inference. Dispersal and establishment abilities were assessed in lentic–lotic species pairs of the complex, using flight wing morphometrics and thermal tolerance ranges as surrogates, respectively. Results There were clear differences in range size between the lotic and lentic taxa of the complex, which appears to have had a lotic origin with two transitions to standing waters. Only small differences were observed in temperature tolerance and acclimation ability between the two lotic–lentic sister species studied. By contrast, wing morphometrics revealed clear, consistent differences between lotic and lentic Enochrus species pairs, the latter having a higher dispersal capacity. Main conclusions We hypothesize that there have been two habitat shifts from lotic to lentic waters, which have allowed marked expansions in geographical range size in western Mediterranean species of the E. bicolor complex. Differences in dispersal rather than in establishment ability appear to underlie differences in geographical range extent, as transitions to lentic waters were associated with changes in wing morphology, but not in thermal tolerance range. In this lineage of water beetles, selection for dispersal in geologically short‐lived lentic systems has driven the evolution of larger range sizes in lentic taxa compared with those of their lotic relatives. 相似文献
10.
Josefa María Navarro María Angeles Botella Antonio Cerd Vicente Martinez 《Journal of plant physiology》2001,158(3)
Melon seedlings (Cucumis melo L. cv.Galia) were grown hydroponically to study the effect of salinity (80 mmol/LNaCl) on phosphate (Pi) uptake and translocation at two levels of Pi (25 μmol/L and 1 mmol/L). Net uptake rates of Pi were determined by depletionof the medium and by plant content. Salinity decreased Pi uptake at low Pi (high affinity uptake mechanism), 25 μmol/L, although no specific competitive inhibition of Pi uptake by Cl− was observed. When plants were grown with high Pi (1 mmol/L), the uptake of Pi through the low affinity system was increased by 80 mmol/L NaCl. Salinity also reduced the phosphorus flux, as Pi, through the xylem. It is hypothesised that high levels of NaCl decrease the mobility of Pi stored in vacuoles, and as a result, inhibit export from this storage compartment to other parts of the plant. 相似文献