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991.
Gómez-Zumaquero JM Rojo-Martínez G García-Escobar E Martín-Nuñez GM Haro J Esteva I Ruiz de Adana M Cuesta AL Olveira G Morcillo S Soriguer F 《Obesity (Silver Spring, Md.)》2008,16(8):1973-1975
The aim of this study was to test the hypothesis of an association between the -30G>A polymorphism of the promoter of the glucokinase gene and the prevalence and incidence of obesity. We studied the -30G>A polymorphism of the glucokinase gene promoter in 981 persons, of whom 866 were seen again 6 years later. All the persons underwent an oral glucose-tolerance test and the BMI (weight/height(2)) was recorded. The -30G>A polymorphism of the glucokinase gene promoter was studied using RFLP-PCR. At the initial study, the probability of having a BMI > or =25 in carriers of the A allele was significantly lower than expected by chance (odds ratio (OR) = 0.63; 95% confidence interval (CI) = 0.456-0.885). In those persons with a BMI > or =30 at the first study, the probability at 6 years of losing weight (reaching a BMI < 30) was greater in carriers of the A allele (OR = 0.22; 95% CI = 0.087-0.576). The increase in weight over these 6 years, taken as a continuous variable, was significantly less only in those persons who were originally obese (P = 0.018). In conclusion, in a population from southern Spain, carriers of the A allele of the -30G>A polymorphism in the promoter of the glucokinase gene had a lower risk for obesity and the likelihood of losing weight was greater in those obese persons who had the A allele (GA or AA). 相似文献
992.
Gallegos Ruiz MI Floor K Roepman P Rodriguez JA Meijer GA Mooi WJ Jassem E Niklinski J Muley T van Zandwijk N Smit EF Beebe K Neckers L Ylstra B Giaccone G 《PloS one》2008,3(3):e0001722
Background
Lung cancer causes approximately 1.2 million deaths per year worldwide, and non-small cell lung cancer (NSCLC) represents 85% of all lung cancers. Understanding the molecular events in non-small cell lung cancer (NSCLC) is essential to improve early diagnosis and treatment for this disease.Methodology and Principal Findings
In an attempt to identify novel NSCLC related genes, we performed a genome-wide screening of chromosomal copy number changes affecting gene expression using microarray based comparative genomic hybridization and gene expression arrays on 32 radically resected tumor samples from stage I and II NSCLC patients. An integrative analysis tool was applied to determine whether chromosomal copy number affects gene expression. We identified a deletion on 14q32.2-33 as a common alteration in NSCLC (44%), which significantly influenced gene expression for HSP90, residing on 14q32. This deletion was correlated with better overall survival (P = 0.008), survival was also longer in patients whose tumors had low expression levels of HSP90. We extended the analysis to three independent validation sets of NSCLC patients, and confirmed low HSP90 expression to be related with longer overall survival (P = 0.003, P = 0.07 and P = 0.04). Furthermore, in vitro treatment with an HSP90 inhibitor had potent antiproliferative activity in NSCLC cell lines.Conclusions
We suggest that targeting HSP90 will have clinical impact for NSCLC patients. 相似文献993.
Liliana Ruiz‐Vásquez Angeles Sonia Olmeda Gustavo Zúñiga Luis Villarroel Luis Fernando Echeverri Azucena González‐Coloma Matías Reina 《化学与生物多样性》2017,14(1)
Nine eremophilane sesquiterpenes 1 – 9 , two flavonoids 11 and 12 , and two known pirrolizidine alkaloids 13 and 14 , were isolated from Senecio adenotrichius DC. Their structures were elucidated on the basis of spectroscopic data and by comparison with previously reported spectroscopic data of similar compounds. Compounds 5 , 7 , and 9 have not been previously reported as natural products. The antifeedant activity of these compounds was tested against Spodoptera litoralis and Myzus persicae. Eremophilanes 1 , 3 , and 8 were strong antifeedants to M. persicae, and 1 and 8 to Spodoptera littoralis. Their ixodicidal activity was tested against the tick Hyalomma lusitanicum, with eremophilanes 1 , 3 , and 8 , being strong ixodicidal agents. 相似文献
994.
Germán Garrote José Francisco Bueno Manuel Ruiz Santiago de Lillo José Manuel Martín Guillermo López Miguel Ángel Simón 《European Journal of Wildlife Research》2017,63(5):79
According to literature, female Iberian lynx (Lynx pardinus) start reproducing at 3 years of age. In more recent years, females breeding at 2 years have been recorded in wild populations. Here, however, we describe the first breeding record for a one-year-old female Iberian lynx. This finding was obtained by camera-trapping data, provided by the yearly monitorization of the species that is carried out across its distribution area. A litter of two lynx kittens was found at the south-east limit of the Andujar-Cardeña population. Two camera-traps were set up near the den to identify the breeding female. Photographs obtained confirmed that the breeding female had already been identified the previous year at less than 3 months of age. The case reported here of a yearling female breeding is the first ever from historical distribution range of the species, and as such, is an exceptional event in the reproduction of the Iberian lynx. 相似文献
995.
996.
Mistletoe species richness patterns are influenced more by host geographic range than nitrogen content
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Mistletoes are hemiparasites that access water and nutrients from their hosts. Previous studies have suggested that host genera with high nitrogen are parasitized by more mistletoe species but these studies failed to take into account phylogenetic relationships among host genera. Our main question was whether more mistletoe species parasitize host genera with high nitrogen content when phylogenetic relationships were controlled. We also asked whether patterns in mistletoe parasitism were related to host geographic range size, host fruit type and host spinescence. Overall, we found no difference between conventional and phylogenetically controlled analyses. We also found no evidence for higher mistletoe species richness on host genera with high nitrogen, fleshy fruits or spinescence. However, similar to findings for animal parasites, we found that host genera with large geographic range had higher mistletoe species richness. This is likely because a greater number of mistletoe species will encounter hosts that have a greater geographic distribution. Mistletoe studies frequently assume that nitrogen status drives patterns in mistletoe parasitism but our study suggests that macroecological patterns in mistletoe assemblages are primarily determined by host geographic range. 相似文献
997.
Anthony Ricciardi Tim M. Blackburn James T. Carlton Jaimie T.A. Dick Philip E. Hulme Josephine C. Iacarella Jonathan M. Jeschke Andrew M. Liebhold Julie L. Lockwood Hugh J. MacIsaac Petr Pyšek David M. Richardson Gregory M. Ruiz Daniel Simberloff William J. Sutherland David A. Wardle David C. Aldridge 《Trends in ecology & evolution》2017,32(11):809-810
998.
Structural overshoot of tree growth with climate variability and the global spectrum of drought‐induced forest dieback
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Alistair S. Jump Paloma Ruiz‐Benito Sarah Greenwood Craig D. Allen Thomas Kitzberger Rod Fensham Jordi Martínez‐Vilalta Francisco Lloret 《Global Change Biology》2017,23(9):3742-3757
Ongoing climate change poses significant threats to plant function and distribution. Increased temperatures and altered precipitation regimes amplify drought frequency and intensity, elevating plant stress and mortality. Large‐scale forest mortality events will have far‐reaching impacts on carbon and hydrological cycling, biodiversity, and ecosystem services. However, biogeographical theory and global vegetation models poorly represent recent forest die‐off patterns. Furthermore, as trees are sessile and long‐lived, their responses to climate extremes are substantially dependent on historical factors. We show that periods of favourable climatic and management conditions that facilitate abundant tree growth can lead to structural overshoot of aboveground tree biomass due to a subsequent temporal mismatch between water demand and availability. When environmental favourability declines, increases in water and temperature stress that are protracted, rapid, or both, drive a gradient of tree structural responses that can modify forest self‐thinning relationships. Responses ranging from premature leaf senescence and partial canopy dieback to whole‐tree mortality reduce canopy leaf area during the stress period and for a lagged recovery window thereafter. Such temporal mismatches of water requirements from availability can occur at local to regional scales throughout a species geographical range. As climate change projections predict large future fluctuations in both wet and dry conditions, we expect forests to become increasingly structurally mismatched to water availability and thus overbuilt during more stressful episodes. By accounting for the historical context of biomass development, our approach can explain previously problematic aspects of large‐scale forest mortality, such as why it can occur throughout the range of a species and yet still be locally highly variable, and why some events seem readily attributable to an ongoing drought while others do not. This refined understanding can facilitate better projections of structural overshoot responses, enabling improved prediction of changes in forest distribution and function from regional to global scales. 相似文献
999.
E. Alfaro-Saiz R. Alonso-Redondo A. Rodríguez J. A. Ruiz de Gopegui L. García M. García-González 《Plant biosystems》2017,151(2):191-203
The aim of this study was to conduct a regional threat-status assessment for Primula pedemontana Thomas ex Gaudin in Spain. This is an Alpine plant with a single isolated Iberian population. A major field survey was made to monitor the species in Spain with a view to preventing its possible disappearance. For that purpose, a habitat study was carried out, regional population size and population structure were determined, and major threats and conservation actions were identified. Besides, habitat suitability maps were drawn up for the present and for 2025 and the percentage of potential habitat loss was calculated in order to estimate their possible evolution. The number of mature individuals, calculated as a trapezoidal fuzzy number, was [9179; 10820; 19002; 22342]. Extent of occurrence and area of occupancy calculated were 2.5 and 0.16 km2, respectively. The regional IUCN category obtained for P. pedemontana was “Critically Endangered”. The percentage of potential habitat loss was estimated at 10.9% for 2025. The authors consider that this species is among the priority Spanish plants for conservation, and that it should be included in the “Spanish List of Wild Species under the Special Protection Scheme”. 相似文献
1000.
Hyperphosphatemia induces senescence in human endothelial cells by increasing endothelin‐1 production
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