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排序方式: 共有1398条查询结果,搜索用时 31 毫秒
21.
Natasha M. van Poppelen Jolique A. van Ipenburg Quincy van den Bosch Jolanda Vaarwater Tom Brands Bert Eussen Frank Magielsen Hendrikus J. Dubbink Dion Paridaens Erwin Brosens Nicole Naus Annelies de Klein Emine Kili Robert M. Verdijk 《International journal of molecular sciences》2021,22(11)
The aim of this study was exploration of the genetic background of conjunctival melanoma (CM) and correlation with recurrent and metastatic disease. Twenty-eight CM from the Rotterdam Ocular Melanoma Study group were collected and DNA was isolated from the formalin-fixed paraffin embedded tissue. Targeted next-generation sequencing was performed using a panel covering GNAQ, GNA11, EIF1AX, BAP1, BRAF, NRAS, c-KIT, PTEN, SF3B1, and TERT genes. Recurrences and metastasis were present in eight (29%) and nine (32%) CM cases, respectively. TERT promoter mutations were most common (54%), but BRAF (46%), NRAS (21%), BAP1 (18%), PTEN (14%), c-KIT (7%), and SF3B1 (4%) mutations were also observed. No mutations in GNAQ, GNA11, and EIF1AX were found. None of the mutations was significantly associated with recurrent disease. Presence of a TERT promoter mutation was associated with metastatic disease (p-value = 0.008). Based on our molecular findings, CM comprises a separate entity within melanoma, although there are overlapping molecular features with uveal melanoma, such as the presence of BAP1 and SF3B1 mutations. This warrants careful interpretation of molecular data, in the light of clinical findings. About three quarter of CM contain drug-targetable mutations, and TERT promoter mutations are correlated to metastatic disease in CM. 相似文献
22.
Although wood–plastic composites have become more accepted and used in recent years and are promoted as low‐maintenance, high‐durability building products, they do experience a color change and a loss in mechanical properties with accelerated weathering. In this study, we attempted to characterize the modulus‐of‐elasticity (MOE) loss of photostabilized high‐density polyethylene (HDPE) and composites of wood flour and high‐density polyethylene (WF/HDPE) with accelerated weathering. We then examined how weathering changed the surface chemistry of the composites and looked at whether or not the surface changes were related to the MOE loss. By examining surface chemistry changes, we hoped to begin to understand what caused the weathering changes. The materials were left unstabilized or were stabilized with either an ultraviolet absorber or pigment. After 1000 and 2000 h of accelerated weathering, the samples were tested for MOE loss. Fourier transform infrared (FTIR) spectroscopy was employed to monitor carbonyl and vinyl group formation at the surface. Changes in the HDPE crystallinity were also determined with FTIR techniques. It was determined that structural changes in the samples (carbonyl group formation, terminal vinyl group formation, and crystallinity changes) could not be reliably used to predict changes in MOE with a simple linear relationship. This indicated that the effects of crosslinking, chain scission, and crystallinity changes due to ultraviolet exposure and interfacial degradation due to moisture exposure were interrelated factors for the weathering of HDPE and WF/HDPE composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2263–2273, 2004 相似文献
23.
Gilles Barnathan Joseph Mirallès Emile M. Gaydou Nicole Boury-Esnault Jean-Michel Kornprobst 《Lipids》1992,27(10):779-784
The fatty acid composition of phospholipids from the Senegalese spongeCinachyrella alloclada was examined. Two new fatty acids not hitherto found in nature, namely 10,13-octadecadienoic acid and 16-tricosenoic acid,
were identified. 8-Hexadecenoic, 13-nonadecenoic and 5,9,13-trimethyltretradecanoic fatty acids were also found for the first
time in sponges. The latter compound (1.4% of the total fatty acid mixture), an isoprenoid fatty acid, accompanies the major
fatty acid 4,8,12-trimethyltridecanoic acid (19.7%). The monomethyl branched fatty acids (22%) identified include 23-methylpentacosanoic
acid (anteiso-26∶0), not previously observed in sponged. The major long-chain fatty acids encountered were the known 17-tetracosenoic
19-heptacosadienoic and 5,9,23-tricontatrienoic acid. Some sixty fatty acids were identified as methyl esters andN-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. 相似文献
24.
Maud Cansell Noredine Moussaoui Alain Pierre Petit Alain Denizot Nicole Combe 《European Journal of Lipid Science and Technology》2006,108(6):459-467
Two n‐3 polyunsaturated fatty acid (PUFA)‐rich diets differing in their chemical and physical forms were given to rats during 2 wk. Liposomes [phospholipids (PL) organized in bilayer structures] made from a natural marine lipid extract or a mixture of fats containing fish oil [similar fatty acids esterified in triacylglycerols (TAG)] were used. The influence of n‐3 PUFA dietary sources on plasma parameters, i.e. TAG, cholesterol and PL concentrations, was investigated. A similar hypotriglyceridemic effect of n‐3 PUFA from liposomes or fish oil was observed. In contrast, feeding rats with liposomes led to different PL and cholesterol patterns. In the plasma of rats fed liposomes, total cholesterol amounts were positively correlated with PL levels. Liposome and fish oil feedings caused a marked increase in the amounts of n‐3 PUFA, which occurred mainly at the expense of n‐6 PUFA. However, the enrichment in n‐3 PUFA in the different plasma lipid classes differed substantially when ingested in the form of fish oil or liposomes. These results were interpreted in terms of different lipid bioavailability and metabolic fate during the digestive steps and in the liver, with the dietary source. 相似文献
25.
Cleland LG Proudman SM Hall C Stamp LK McWilliams L Wylie N Neumann M Gibson RA James MJ 《Lipids》2003,38(4):419-424
Dietary fish oil supplements have been shown to have benefits in rheumatoid arthritis (RA), other inflammatory diseases, and
in cardiovascular disease. As with any medical advice, variability will exist with regard to adherence and consequent biochemical
or pharmacophysiologic effects. The aim was to explore the utility of plasma phospholipid EPA as a measure of n−3 PUFA intake
and response to standardized therapeutic advice given in an outpatient or office practice setting, to increase dietary n−3
PUFA, including a fish oil supplement. Patients with early RA were given verbal and written advice to alter their dietary
n−3 PUFA intake, including ingestion of 20 mL of bottled fish oil on juice daily. The advice included instructions to increase
n−3 PUFA and to avoid foods rich in n−6 PUFA. Every 3 mon, blood samples were obtained for analysis of plasma phospholipid
FA. Plasma phospholipid EPA was used as the primary index of n−3 PUFA intake. A diverse response was seen, with about one-third
of patients achieving a substantial elevation of plasma phospholipid EPA over the 12-mon study period. A third had little
change, with the remainder achieving intermediate levels. Data obtained longitudinally from individual patients indicated
that substantial elevations of EPA (>5% total plasma phospholipid FA) could be maintained for more than 3 yr. Plasma phospholipid
EPA is a convenient measure of adherence to advice to take a dietary n−3 PUFA-rich fish oil supplement. This measure may prove
a useful adjunct to intention to treat analyses in determining the effect of dietary fish oil supplements on long-term outcomes
in arthritis and other chronic inflammatory diseases. It may also provide a guide to the effectiveness of therapeutic and
preventive messages designed to increase n−3 PUFA intake. 相似文献
26.
Cherif M. Azzaz Luiz H. C. Mattoso Nicole R. Demarquette Ricardo J. Zednik 《应用聚合物科学杂志》2021,138(10):49959
Considerable effort has been devoted to improving the properties of PVDF (polyvinylidene fluoride), arguably the most technologically important piezoelectric polymer. Electrospinning has been found to be a particularly effective method of producing PVDF nanofibers with superior piezoelectric properties due to the resulting exceptionally high fraction of the piezoelectrically active crystalline β-phase. It is typically assumed that the high external electric fields applied during electrospinning enhance the formation of this β-phase, with the confused literature offering various unsatisfactory mechanistic explanations. However, by comparing PVDF nanofibers produced by two different processes (electrospinning and blowspinning), we show that the electric field is entirely unnecessary; indeed, the crystallization dynamics are principally driven by the applied mechanical stress, as evidenced by structurally identical 200 nm diameter PVDF fibers produced with and without external electric fields. 相似文献
27.
Nicole Basaraba Owen Conlan Jennifer Edmond Peter Arnds 《New Review of Hypermedia and Multimedia》2013,19(1-2):1-30
ABSTRACTGalleries, libraries, archives and museums (GLAMs) are increasingly using digital technologies for storytelling and creating mobile applications (apps) for cultural heritage content, but how apps are used in practice to communicate information to users has not been widely studied. A team of people from a heritage organisation, a university, and mobile app development group plan to create a bespoke heritage trail app for Ireland, but to date design conventions/recommendations for this genre are lacking. This article applies a systematic approach to digital narrative content analysis to better understand how apps are being used specifically for heritage trails with the aim of identifying what the common features are, which modalities and narrative techniques are used. The selected corpus included 55 apps downloaded from the Google Play Store. The results of this content analysis—based on the App Walkthrough Method (Light, B., Burgess, J., & Duguay, S. (2018). The walkthrough method: An approach to the study of apps. New Media & Society, 20(3), 881–900)—show that there is a gap between academic research themes/trends and how digital narrative is actually being communicated in the current market, and it aims to inform the future development of heritage trail apps by including a list of design and content features common to this genre. 相似文献
28.
Economic forces, competitive pressures and technological advances have created an environment within which firms have developed new ways of organizing (e.g. virtual work settings) and managing their resources (e.g. knowledge management) in order to maintain and improve firm performance. Extant research has highlighted the challenges associated with managing knowledge in virtual settings. However, researchers are still struggling to provide effective guidance to practitioners in this field. We believe that a better understanding of individual virtual competency is a potential avenue for managing the complexity of knowledge transfer in virtual settings. In particular, we suggest that optimal knowledge transfers can be achieved by individuals armed with the right personal capabilities and skills for virtual work, particularly when those knowledge transfers are emergent, bottom-up and cannot be specified a priori. The virtual competency exhibited by individuals can be the key to overcoming the constraints of knowledge transfers with such characteristics because underlying competency can facilitate effective action in unfamiliar and novel situations. In this conceptual research, we develop a theoretical model of individual virtual competence and describe its role in the communication process, which underpins effective knowledge transfer in virtual settings. Additionally, we consider the antecedent role that prior experience in virtual activity plays in aiding workers to develop virtual competence, which in turn engenders effective knowledge transfer. We conclude with implications for future research and for practicing managers. 相似文献
29.
Wurster Marco Michel Marius May Marvin Carl Kuhnle Andreas Stricker Nicole Lanza Gisela 《Journal of Intelligent Manufacturing》2022,33(2):575-591
Journal of Intelligent Manufacturing - Remanufacturing includes disassembly and reassembly of used products to save natural resources and reduce emissions. While assembly is widely understood in... 相似文献
30.
Julie M. Vandenbossche Nicole Dufalla Zichang Li 《International Journal of Pavement Engineering》2017,18(11):1004-1015
Bonded concrete overlays of asphalt pavements (BCOAs) are becoming a common rehabilitation technique used for distressed hot mix asphalt (HMA) roadways. The original design procedures were based primarily on data from instrumented pavements and finite element modelling. They were governed by the assumption that the failure mechanism was a function of the overlay thickness. However, field observations have indicated that the actual failure modes are dictated by slab size. The newly developed Bonded Concrete Overlay of Asphalt Mechanistic-Empirical design procedure (BCOA-ME) presented here is valid for overlays that are between 2.5 and 6.5 in (64–154 mm), and includes five primary enhancements to the Portland Cement Association and Colorado Department of Transportation procedures that have been traditionally used: 1.) the failure mode is dictated by the joint spacing; 2.) a new structural model for longitudinal cracking for 6-ft × 6-ft (1.8 m × 1.8 m) concrete overlays has been developed to better predict the critical stresses; 3.) the stress adjustment factors have been calibrated with performance data; 4.) the equivalent temperature gradients used as design input are defined based on the pavement structure and geographical location of the project; and 5.) the effect of temperature change on underlying HMA stiffness is considered. Finally, validation studies were completed on the new procedure and comparisons made between the revised procedure and actual performance data for five separate projects showed reasonable results. A sensitivity analysis also revealed that the predicted thickness obtained using the revised procedure was sensitive to HMA thickness, the modulus of rupture of the Portland cement concrete, and the level of traffic, as would be expected. 相似文献