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排序方式: 共有671条查询结果,搜索用时 31 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.
César I. Beristain Ebner Azuara Hugo S. Garcia & Eduardo J. Vernon-Carter 《International Journal of Food Science & Technology》1996,31(5):379-386
The water and oil uptake of mesquite and arabic gums in powdered form was studied at temperatures of 23, 35 and 45°C. A previously proposed equation to predict osmotic equilibrium was tested using the experimental data with both gums and a good statistical fit was obtained. Mesquite gum showed the highest water and oil absorption at all temperatures studied. Temperature dependence of the reciprocal of the S1 and WL∞ were determined using an Arrhenius equation. The activation energy for water and oil absorption for gum arabic was 21.98 and 39.57 kJ mol−1 , compared to that of mesquite gum having values of 15.79 and 46.16 kJ mol−1 , respectively. A second order kinetic model was obtained for water and oil absorption for both gums. 相似文献
3.
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
4.
5.
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
6.
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
7.
L Bauer B Bohle B Jahn-Schmid U Wiedermann A Daser H Renz D Kraft C Ebner 《Canadian Metallurgical Quarterly》1997,107(3):536-541
Several in vitro and in vivo studies indicate that application of high doses of dominant T cell epitopes can induce a state of antigen-specific non-responsiveness (anergy). In the present study, we developed a murine model of an allergic immune response to Bet v 1, the major birch pollen allergen. Mice were sensitized by injection of rBet v 1 and the allergic state was proven by the presence of allergen-specific IgE and positive immediate-type skin tests to Bet v 1. In epitope mapping experiments, an immunodominant T cell epitope of Bet v 1 in BALB/c mice was identified by the use of overlapping peptides. This peptide (BV 139) was subsequently employed for treatment. Two tolerization protocols were used: in one approach, the peptide was administered to naive mice before immunization (group BV139-S), in the second, already sensitized mice were treated (S-BV139). The results demonstrated that administering high doses of the dominant T cell epitope of Bet v 1 profoundly diminished T cell proliferation to the peptide in the BV139-S group, and to the peptide as well as to the whole protein in the S-BV139 group. Skin test reactivity to Bet v 1 was reduced in the BV139-S group. However, no differences in terms of specific antibody production between treated and untreated mice could be observed. This study provides evidence that administration of dominant T cell epitopes can down-regulate the allergen-specific T cell response. Proceeding on the assumption that the T lymphocyte response to allergens is crucial for the induction and maintenance of the allergic disease, a modulation of the immune response to allergens by treatment with T cell epitope peptides could represent a promising concept for immunotherapy in the future. 相似文献
8.
In this paper, we present results on the structure, optical properties and corrosion behaviour of Zr-B and Zr-B-N coatings employing non-reactive and reactive d.c. magnetron sputter deposition. The addition of nitrogen reduced the grain size—coatings deposited at nitrogen flow rates f(N2) of less than approximately 14 sccm (standard cm3 min-1) were extremely fine grained, while nitrogen flow rates of more than 14sccm led to fracture-amorphous coatings with a very smooth surface. The hardness and abrasion resistance decreased with the increase in nitrogen content. Pure Zr-B coatings are silver-greyish with metallic brilliance but nitrogen changes the colour from dark grey or black at low contents to interference colours in the amorphous state. Ellipsometric measurements of the refractive index n and adsorption coefficient k supported the results derived from electron microscopy, colour measurements and mechanical testing. The transition point between the fine-grained and fracture-amorphous structure lies in the range of f(N2) around 10 sccm. The black coatings deposited with such nitrogen levels showed good corrosion and abrasion resistance combined with a satisfying hardness. In some cases, increasing the nitrogencontent improved the corrosion resistance. In potentio- dynamic experiments, more positive free corrosion and pitting potentials were demonstrated. However, in salt spray testing and immersion testing using an artificial sweat solution, no beneficial effect of high nitrogen additions was noticed. Zr-B-N coatings deposited with nitrogen flow values in the range 10–20 sccm offer an excellent choice for decorative purposes, owing to their dark grey or intense black colour and good corrosion resistance. 相似文献
9.
Maria Luz Fernandez A. Karin Conde Laura R. Ruiz Carlos Montano John Ebner Donald J. McNamara 《Lipids》1995,30(7):619-626
To test the effects of exchanging dietary complex and simple carbohydrate for fat calories on lipoprotein metabolism, guinea
pigs were fed two different fat/carbohydrate ratios: 2.5∶58% (w/w) or 25∶29% (w/w) with either sucrose or starch as the carbohydrate
source. Animals fed high-fat had higher plasma low-density lipoprotein (LDL) and hepatic cholesterol concentrations than animals
fed low-fat diets (P<0.01). The cholesteryl ester content per particle was higher, and the number of triacylglycerol (TAG) molecules was lower
in very low density lipoprotein (VLDL) and LDL from animals fed high-fat diets. Intake of high-fat/sucrose resulted in higher
plasma LDL concentrations than intake of high-fat/starch, and animals fed low-fat/starch had the highest plasma TAG concentrations
associated with VLDL particles containing more TAG molecules, as well as a TAG-enriched LDL. The activity of plasma lecithin
cholesteryl:acyl transferase (LCAT) was highest in animals fed high-fat/sucrose, and heart lipoprotein lipase (LPL) activity
was higher in animals fed high-fat diets. Hepatic apoprotein B/E (apo B/E) receptor number (Bmax) was increased 21% with low-fat diets (P<0.01). These results suggest that the hypercholesterolemia induced by high-fat and by sucrose intake are associated with
a higher plasma LCAT activity which results in a cholesteryl ester-enriched VLDL which, by the action of LPL, might be more
readily converted to LDL through the delipidation cascade leading to downregulation of hepatic apo B/E receptors. The hypertriglyceridemia
associated with low-fat intake may result from increased production of VLDL TAG, which would explain the increased TAG content
and the higher TAG/CE ratio of VLDL from animals fed the low-fat/starch diet. 相似文献
10.
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