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排序方式: 共有647条查询结果,搜索用时 15 毫秒
1.
Sarah Gilgunn Keefe Murphy Henning Stckmann Paul J. Conroy T. Brendan Murphy R. William Watson Richard J. OKennedy Pauline M. Rudd Radka Saldova 《International journal of molecular sciences》2020,21(23)
The diagnosis and treatment of prostate cancer (PCa) is a major health-care concern worldwide. This cancer can manifest itself in many distinct forms and the transition from clinically indolent PCa to the more invasive aggressive form remains poorly understood. It is now universally accepted that glycan expression patterns change with the cellular modifications that accompany the onset of tumorigenesis. The aim of this study was to investigate if differential glycosylation patterns could distinguish between indolent, significant, and aggressive PCa. Whole serum N-glycan profiling was carried out on 117 prostate cancer patients’ serum using our automated, high-throughput analysis platform for glycan-profiling which utilizes ultra-performance liquid chromatography (UPLC) to obtain high resolution separation of N-linked glycans released from the serum glycoproteins. We observed increases in hybrid, oligomannose, and biantennary digalactosylated monosialylated glycans (M5A1G1S1, M8, and A2G2S1), bisecting glycans (A2B, A2(6)BG1) and monoantennary glycans (A1), and decreases in triantennary trigalactosylated trisialylated glycans with and without core fucose (A3G3S3 and FA3G3S3) with PCa progression from indolent through significant and aggressive disease. These changes give us an insight into the disease pathogenesis and identify potential biomarkers for monitoring the PCa progression, however these need further confirmation studies. 相似文献
2.
This article is the second of two papers that review the field of spatially sensitive social scientific research into the links between social status and transport disadvantage. The first paper undertook a comprehensive review of the social scientific and transport planning literature to mark the level of development in the field and identify conceptual and methodological issues and constraints in this field of inquiry. The present article supports the advancement of socially and geographically sensitive transport research by opportunities for the development of more sophisticated spatial analytical methodologies. The approach we present is able to account for factors not previously addressed in either social or transport planning research, in particular the temporal dimensions of transport service accessibility. The article articulates the methodology through an empirical case study of socio-spatial transport disadvantage within the Gold Coast City. The article demonstrates that there are important theoretical and practical lessons to be gained for researchers and policy makers in addressing the social dimensions of transport and infrastructure provision. Further, the article argues that an attentiveness to new ways of combining and representing social and transport data-sets can promote policy relevant empirical social inquiry. The article also contributes in a productive way to the empirical knowledge of Australia's sixth-largest metropolitan area, which is often overlooked by urban scholars. 相似文献
3.
Bradley Brendan P.; Gossop Michael; Brewin Chris R.; Phillips Grania; Green Lynette 《Canadian Metallurgical Quarterly》1992,60(3):470
Investigated whether attributions of opiate addicts would predict both their ability to abstain from future use and their reactions to abstinence violations. Measures of generalized beliefs about responsibility for positive and negative outcomes and specific attributions about relapse episodes were elicited from 80 addicts at the time of admission for inpatient detoxification and treatment. Addicts who at admission attributed to themselves greater responsibility for negative outcomes and who attributed relapse episodes to more personally controllable factors were subsequently (at 6-mo follow-up) more likely either to be completely abstinent or to contain the effects of temporary lapses into opiate use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Brendan McGrath 《Cities》1992,9(4)
Port Moresby is the capital of Papua New Guinea. With a population of nearly 200 000 it is by far the largest city in the country. Officially called the National Capital District (NCD), it straddles a low range of coastal hills in the south-east corner of the New Guinea mainland. It is a city facing serious problems today. A narrow economic base, a lack of land suitable for development and a deteriorating law and order situation are compounded by very rapid growth. The proposed construction of a transisland highway this decade, connecting Port Moresby to the populous interior, would have a profound impact on the future of the city. 相似文献
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Wagner's criterion to predict the minimum concentration of solute (N
B(min)
0
)necessary for the exclusive formation of its scale has been modified to incorporate both thermodynamic and kinetics requirements. The analysis presented here involves a receding alloy/scale interface for which the composition of the alloy at this interface is governed by thermodynamic equilibrium between the two competing scale phases and the base alloy. This is a more rigorous analysis than that of Wagner's, who assumed the alloy/scale interface to be immobile and the solute composition at the interface to be zero. A comparison is made between values of N
B(min)
0
found experimentally and those predicted by Wagner's and the present criterion for a number of alloy-gas systems. It is shown that the criterion developed in the present analysis can often provide a better approximation of the actual N
B(min)
0
.The expressions derived from the present analysis have been extended also in a semiquantitative manner to provide a criterion for the minimum amount of solute in the alloy required for the transition from internal to external scale formation. 相似文献
8.
The cyclic-oxidation behavior of commercial iron-base 800-series chromia-scale-forming alloys was studied at 1000°C in still air. Each thermal cycle consisted of one day at temperature followed by air cooling to room temperature. Two different types of 800-series alloys were studied (800 and 800HT), with each type being supplied by two different producers. Although the alloys were of similar chemical composition, their variations in minor-constituent contents were apparently sufficiently different to cause marked differences in oxidation behavior. Compared to the 800 alloys, the higher-strength 800HT alloys generally performed the worst, undergoing rapid weight-loss kinetics after an initial period of relatively protective oxidation. The time required for the commencement of rapid weight-loss kinetics depended significantly on the producer of the 800HT alloy. In general, however, the 800HT alloys developed protrusion of Ti- and Cr-rich oxides into the alloy along the alloy/scale interface, which promoted spallation and poorer cyclic-oxidation resistance. The formation of Si-rich oxide particles in the vicinity of the alloy/scale interface could improve cyclic-oxidation resistance; however, higher Si contents would cause internal Si-rich oxide formation and promote the formation of Ti- and Cr-rich oxide protrusions at the alloy/scale interface. Good cyclic-oxidation resistance requires optimization of the minor-element constituents, Si, Ti, and Al in particular. 相似文献
9.
Brendan S. Gillon 《Journal of Logic, Language and Information》2014,23(3):275-285
In this paper, I address the problem wherein the same English word permits one of its complement positions to be satisfied by phrases of different categories. A well-known example of such an English word is the copula to be, whose complements include adjective phrases, noun phrases, prepositional phrases and adverbial phrases. I provide a way to treat such words, in particular verbs, as single lexical items through a conservative extension of the usual treatment of word classification as a pair comprising a part of speech category and a complement list. I then show how a further conservative extension of complement lists permits a satisfactory formalization of doubly complemented English verbs which are synonymous under a permutation of their complements. These verbs include, but are not limited to, so-called double object constructions. 相似文献
10.
The catalytic activities of a range of hydrogen reduced nickel Y zeolites for the hydrogenation of toluene were measured and correlated with the following catalytic parameters: reaction temperature; reaction time; coke deposition. The role of the alkali metal co-cation (Li+, Na+, K+, Rb+ or Cs+) in influencing the overall hydrogenation activity of the supported nickel metal was probed. The effect of poisoning the surface Bronsted acidity by the adsorption of ammonia is discussed. For comparative purposes, data on the hydrogenation of benzene over the same catalysts are included. 相似文献