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排序方式: 共有263条查询结果,搜索用时 31 毫秒
71.
Mingjun Zheng Heather Mullikin Anna Hester Bastian Czogalla Helene Heidegger Theresa Vilsmaier Aurelia Vattai Anca Chelariu-Raicu Udo Jeschke Fabian Trillsch Sven Mahner Till Kaltofen 《International journal of molecular sciences》2020,21(23)
(1) Background: Biomarkers might play a significant role in predicting the clinical outcomes of patients with ovarian cancer. By analyzing lipid metabolism genes, future perspectives may be uncovered; (2) Methods: RNA-seq data for serous ovarian cancer were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. The non-negative matrix factorization package in programming language R was used to classify molecular subtypes of lipid metabolism genes and the limma package in R was performed for functional enrichment analysis. Through lasso regression, we constructed a multi-gene prognosis model; (3) Results: Two molecular subtypes were obtained and an 11-gene signature was constructed (PI3, RGS, ADORA3, CH25H, CCDC80, PTGER3, MATK, KLRB1, CCL19, CXCL9 and CXCL10). Our prognostic model shows a good independent prognostic ability in ovarian cancer. In a nomogram, the predictive efficiency was notably superior to that of traditional clinical features. Related to known models in ovarian cancer with a comparable amount of genes, ours has the highest concordance index; (4) Conclusions: We propose an 11-gene signature prognosis prediction model based on lipid metabolism genes in serous ovarian cancer. 相似文献
72.
Helene McDowell Eunkyung Kim Bret R. Shaw Jeong Yeob Han Lauren Gumieny 《Journal of Computer-Mediated Communication》2010,15(3):412-426
Many breast cancer patients currently turn to Internet‐based education and support to help them cope with their illness. This study explores the role of training in influencing how patients use a particular Interactive Cancer Communication System (ICCS) over time and also examines what pre‐test characteristics predict which people are most likely to opt in or out of training in the first place. With use of pre‐test survey and unobtrusive individual records of ICCS system use data (N = 216), nonparametric tests revealed that only having a later stage of cancer predicted whether or not patients participated in training. Results indicated that participating in training was a significant predictor of higher levels of using the CHESS system. In particular, the repeated measures analysis of covariance found the significant interaction as well as main effect of group (i.e., training vs. no training) and time (i.e., individual's CHESS usages at different times) in interactive and information CHESS services, suggesting that 1) the training group has a higher level of usage than the no training group, 2) both of the groups' usage decreased over time, and 3) these joint patterns hold over time. Practical guidelines for future ICCS campaign implementation are discussed. 相似文献
73.
Simone Mazzucato Henri Lehec Helene Carrère Hajer Makhloufi Alexandre Arnoult Chantal Fontaine Thierry Amand Xavier Marie 《Nanoscale research letters》2014,9(1):19
The exciton recombination processes in a series of elastically strained GaAsBi epilayers are investigated by means of time-integrated and time-resolved photoluminescence at T = 10 K. The bismuth content in the samples was adjusted from 1.16% to 3.83%, as confirmed by high-resolution X-ray diffraction (HR-XRD). The results are well interpreted by carrier trapping and recombination mechanisms involving the Bi-related localized levels. Clear distinction between the localized and delocalized regime was observed in the spectral and temporal photoluminescence emission. 相似文献
74.
Preparation and characterization of plasticized starch/halloysite porous nanocomposites possibly suitable for biomedical applications 下载免费PDF全文
Helene Schmitt Nicolas Creton Kalappa Prashantha Jeremie Soulestin Marie‐France Lacrampe Patricia Krawczak 《应用聚合物科学杂志》2015,132(4)
Novel porous bionanocomposites based on halloysite nanotubes as nanofillers and plasticized starch as polymeric matrix were successfully prepared by melt‐extrusion. Foaming was obtained by adding water as natural blowing agent, and by increasing the die temperature. Both the expansion ratio and the porosity increase with increasing die temperature. Addition of high water content allows reducing the foaming temperature. Moreover, the introduction of halloysite has double benefits: these fillers act both as a nucleating agent increasing the porosity and as a barrier agent increasing the proportion of small cells. Foams based on plasticized starch with a blend of glycerol and sorbitol loaded with 6 wt % of halloysite, extruded at 117°C, present the cellular structure and the mechanical properties required for scaffold applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41341. 相似文献
75.
The effect of relative humidity (RH) on the adhesion of particles colliding with a hard surface was studied for submicron particles of liquid oleic acid, solid ammonium sulfate, and solid polystyrene latex (PSL). For this purpose, a three-arm impactor was designed and constructed. The three arms consisted of one impactor having an uncoated impaction plate (i.e., a rebound arm), one impactor having a viscous-liquid-coated impaction plate (i.e., a capture arm), and one impactor having no impaction plate (i.e., a null arm). The particle number concentrations downstream of each arm were measured by condensation particle counters (CPCs). Data were analyzed to obtain the particle rebound fraction. Use of ambient upstage pressure allowed measurements from 5 to 95% RH at the impaction plate. Particle rebound depended strongly on RH, even for non-hygroscopic PSL particles. The rebound fraction for PSL particles dropped monotonically from nearly unity at 50% RH to 0.4 at 95% RH. For ammonium sulfate, the rebound fraction dropped from nearly unity at 25% RH to 0.5 at 70% RH. The decreased rebound at higher RH was explained by the formation of a water meniscus. The resulting capillary forces inhibited particle detachment. A model, taking into account the impact kinetic energy compared to the contact adhesion energy arising from van der Waals and capillary forces, captured the observations well. The reduced rebound arising from increased adhesion at high RH, independent of particle water content, potentially confounds a recent assumption that non-rebounding atmospheric particles are liquid.
Copyright 2014 American Association for Aerosol Research 相似文献
76.
Li He Helene Berntsen Esther Ochoa-Fernández John C. Walmsley Edd A. Blekkan De Chen 《Topics in Catalysis》2009,52(3):206-217
A series of Co–Ni catalysts, prepared from hydrotalcite (HT)-like materials by co-precipitation, has been studied for the
hydrogen production by ethanol steam reforming. The total metal loading was fixed at 40% and the Co–Ni composition was varied
(40–0, 30–10, 20–20, 10–30 and 0–40). The catalysts were characterized using X-ray diffraction, N2 physisorption, H2 chemisorption, temperature-programmed reduction, scanning transmission electron microscope and energy dispersive spectroscopy.
The results demonstrated that the particle size and reducibility of the Co–Ni catalysts are influenced by the degree of formation
of a HT-like structure, increasing with Co content. All the catalysts were active and stable at 575 °C during the course of
ethanol steam reforming with a molar ratio of H2O:ethanol = 3:1. The activity decreased in the order 30Co–10Ni > 40Co ~ 20Ni–20Co ~ 10Co–30Ni > 40Ni. The 40Ni catalyst displayed
the strongest resistance to deactivation, while all the Co-containing catalysts exhibited much higher activity than the 40Ni
catalyst. The hydrogen selectivities were high and similar among the catalysts, the highest yield of hydrogen was found over
the 30Co–10Ni catalyst. In general, the best catalytic performance is obtained with the 30Co–10Ni catalyst, in which Co and
Ni are intimately mixed and dispersed in the HT-derived support, as indicated by the STEM micrograph and complementary mapping
of Co, Ni, Al, Mg and O. 相似文献
77.
Hydroxy-PCBs, PBDEs, and HBCDDs in serum from an elderly population of Swedish fishermen's wives and associations with bone density 总被引:1,自引:0,他引:1
Weiss J Wallin E Axmon A Jönsson BA Akesson H Janák K Hagmar L Bergman A 《Environmental science & technology》2006,40(20):6282-6289
Lack of human exposure data is frequently reported as a critical gap in risk assessments of environmental pollutants, especially regarding "new" pollutants. The objectives of this study were to assess serum levels of the persistent 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), hydroxylated polychlorinated biphenyl metabolites (OH-PCBs), polybrominated diphenyl ethers (PBDEs), and hexabromocyclodode-canes (HBCDDs) in a group of Swedish middle-aged and elderly women expected to be relatively highly exposed, and to evaluate the impact of potential determinants (e.g., fish intake, age) for the inter-individual variation, as well as to investigate the association between these pollutants and bone density. No associations were found between bone mineral density or biochemical markers of bone metabolism and the analyzed environmental pollutants. Relatively high levels of CB-153 (median 260 ng/g fat) and sigma 3-OH-PCBs (median 1.7 ng/mL serum), and low concentrations of sigma6PBDEs (median 3.6 ng/g fat) were determined. Total level of HBCDDs in serum was quantified by gas chromatography with mass spectrometric detection (median 0.5 ng/g fat). HBCDD diastereomeric and enantiomeric patterns were determined by liquid chromatography with mass spectrometric detection. The dominating stereoisomer was (-)alpha-HBCDD, but 1-3% of gamma-HBCDD was also detected in the serum samples. 相似文献
78.
Near-Infrared Reflectance Spectroscopy is a Rapid, Cost-Effective Predictor of Seagrass Nutrients 总被引:1,自引:0,他引:1
Near-infrared reflectance spectroscopy was used to analyze nutrient composition of tropical and subtropical seagrasses in Queensland, Australia, as part of a broader study of impacts of grazing by dugongs on seagrass. Seagrass samples of 10 species were collected, transported to the laboratory, and separated into leaf and root/rhizome fractions. They were dried, ground, and near-infrared spectra (400–2500 nm) were collected. We used partial least-squares regression to develop calibration equations relating spectral data to standard compositional analyses performed in the laboratory. These compositional analyses focused on attributes believed to be important determinants of nutritional quality of marine vertebrate herbivores (nitrogen, organic matter, neutral detergent fiber, acid detergent fiber, lignin, neutral starch, water-soluble carbohydrates, and in vitro dry matter digestibility). Calibration equations for each attribute were developed separately for (1) roots/rhizomes and (2) leaves, irrespective of plant species. An equation that combined both plant parts was equally robust. These studies demonstrated the utility of near-infrared spectroscopy in providing rapid and cost-effective analysis of marine plants, which, in turn, permits a rigorous statistical approach to be applied to studies of foraging by marine herbivores. 相似文献
79.
Powell Martine B.; Roberts Kim P.; Ceci Stephen J.; Hembrooke Helene 《Canadian Metallurgical Quarterly》1999,35(6):1462
The effect of suggestive questions on 3- to 5-year old and 6- to 8-year old children's recall of the final occurrence of a repeated event was examined. The event included fixed (identical items) as well as variable items where a new instantiation represented the item in each occurrence of the series. Relative to reports of children who participated in a single occurrence, children's reports about fixed items of the repeated event were more accurate and less contaminated by false suggestions. For variable items, repeated experience led to a decline in memory of the specific occurrence; however, there was no increase in susceptibility to suggestions about details from nontarget occurrences. Although younger children and children who were interviewed a while after the event were more suggestible, respectively, than older children and those interviewed soon after the event, repeated experience attenuated these effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Socioemotional selectivity theory holds that as people recognize the inevitable constraint of time imposed by mortality, their social goals change, motivating them to limit social contacts to those with whom they are emotionally close. This theory was tested among Taiwanese and Mainland Chinese. As predicted, results showed that older adults (aged 60–90 years) in both cultures were more likely than younger adults (aged 18–30 years) to prefer familiar social partners who were most likely to provide emotionally close social interactions. Mainland Chinese, who as a group have shorter actuarial life expectancy, were more likely to prefer familiar social partners than were Taiwanese. These age and cultural differences were eliminated when differences in perceived time were statistically controlled for. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献