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排序方式: 共有421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.
Kilchytska V. Neve A. Vancaillie L. Levacq D. Adriaensen S. van Meer H. De Meyer K. Raynaud C. Dehan M. Raskin J.-P. Flandre D. 《Electron Devices, IEEE Transactions on》2003,50(3):577-588
This work presents a systematic comparative study of the influence of various process options on the analog and RF properties of fully depleted (FD) silicon-on-insulator (SOI), partially depleted (PD) SOI, and bulk MOSFET's with gate lengths down to 0.08 /spl mu/m. We introduce the transconductance-over-drain current ratio and Early voltage as key figures of merits for the analog MOS performance and the gain and the transition and maximum frequencies for RF performances and link them to device engineering. Specifically, we investigate the effects of HALO implantation in FD, PD, and bulk devices, of film thickness in FD, of substrate doping in SOI, and of nonstandard channel engineering (i.e., asymmetric Graded-channel MOSFETs and gate-body contacted DTMOS). 相似文献
3.
Wettability of polyimide (PI) and polypropylene (PP) films have been improved using SiOx-like thin layers deposited from a mixture of hexamethyldisiloxane (HMDSO) and oxygen in a microwave distributed electron cyclotron resonance plasma reactor. The films wettability evolution behaviors were evaluated through the results of contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The plasma depositions of SiOx thin layers in presence of VUV radiation induce a contact angle decrease to about 7° and 35° for PI and PP films, respectively. XPS data showed that such difference in wettability is attributed to the increase of hydrophilic group's proportion at the surface of coated PI films due to VUV irradiation. AFM images showed that the PI surface topography remains relatively smooth when coated in presence of VUV radiation. However, in the case of PP films, AFM images revealed the growth of irregular structure due to a substrate etching effect supported by VUV radiation. For polymers coated without VUV irradiation, the deconvolution of the C1s peaks showed a significant decrease of CO bonds for both PI and PP substrates. 相似文献
4.
T Ojasoo E Bignon A Crastes de Paulet JC Doré J Gilbert JF Miquel M Pons JP Raynaud 《Canadian Metallurgical Quarterly》1993,44(3):239-250
A multivariate statistical method, correspondence factorial (CF) analysis, was used to examine the correlations among the protein binding and cell proliferation effects of a series of 36 di- and triphenylethylenes (DPEs and TPEs). The analysis was applied to a study which measured their competition for estradiol binding to cytosol estrogen receptor (ER), their influence on protein kinase C (PKC) activity under different conditions of enzyme activation, their ability to promote the growth of a breast cancer cell line and to inhibit growth at high concentrations (cytotoxicity). The CF analysis revealed several levels of correlation. First, it distinguished those molecules within the population that stimulated rather than inhibited PKC activity. Second, it made apparent a strong correlation between cytotoxicity and inhibition of Ca++ and phosphatidylserine-dependent PKC activity, which was most marked when the enzyme had been activated by diacylglycerol indicating that PKC inhibition under physiological conditions might contribute to the overall cytotoxicity of these compounds. Third, a lower level of correlation was established between competition for ER binding and cytotoxicity. Taken together, the results suggest that MCF7 cells might be most sensitive to a cytotoxic effect of TPEs (via PKC and other targets) when they at the same time decrease estrogen-stimulated proliferation via an ER-mediated antiestrogenic effect. 相似文献
5.
To determine if the sexually dimorphic area (SDA) of the gerbil hypothalamus affects male sexual behavior through its projections to the retrorubral field (RRF) or ventrolateral periaqueductal gray (PAGvl), these pathways were lesioned asymmetrically. Unilateral radio frequency lesions of the lateral SDA (LSDA), the major source of the pathways, impaired mating when combined with contralateral RRF, but not PAGvl, lesions. N-methyl-{d}-aspartate (NMDA) lesions of the medial SDA, LSDA, and the area between them (the total pathway source) eliminated mating when combined with contralateral, but not ipsilateral, NMDA lesions of the RRF. To determine if A8 cells contributed to these effects, males received NMDA in the SDA and NMDA or 6-hydroxydopamine in the contralateral RRF. When combined with large SDA lesions, A8 lesions impaired but did not eliminate mating. Thus the SDA–RRF pathway, but not an SDA-A8 pathway, is essential for sexual behavior in male gerbils. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Stephen J. Allen Pauline A. Brown 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):17-24
The adsorption of the three metal ions, copper, cadmium and zinc in single component and multi-component mixtures in aqueous solutions by lignite is reported. A comparison is made between the single component saturation uptake and the multi-component uptakes. The isotherms indicate a competitive uptake with copper being preferentially absorbed by the lignite in multi-component solutions. The isotherms are plotted to obtain the Langmuir constants, the Freundlich constants and the Redlich–Peterson constants. Lignite is shown to possess an affinity for the metal ions which make its use as an adsorbent a possible alternative to the use of more expensive activated carbons. 相似文献
7.
Raynaud C. Gautier J. Guegan G. Lerme M. Playez E. Dambrine G. 《Electron Device Letters, IEEE》1991,12(12):667-669
Polycide-gate silicon n-channel MOSFETs were fabricated on the basis of a standard 0.5-μm MOS technology and measured over the 1.5-26.5-GHz frequency range, in order to investigate the effects of channel-length reduction on device behavior at high frequency. Excellent microwave performances were obtained with a maximum operating frequency (f max) and a unity-current-gain frequency f t near 20 GHz for 0.5-μm-gate-length NMOS devices. An equivalent circuit for a MOSFET with its parasitic elements was extracted from measured S-parameter data. The influence of gate resistance, gate-to-drain overlap capacitance, substrate conductivity, and the transit-time effect between the source and drain on microwave characteristics was analyzed 相似文献
8.
Pauline V. Marck Marco T. Pessoa Yunhui Xu Laura C. Kutz Dominic M. Collins Yanling Yan Cierra King Xiaoliang Wang Qiming Duan Liquan Cai Jeffrey X. Xie Jerry B. Lingrel Zijian Xie Jiang Tian Sandrine V. Pierre 《International journal of molecular sciences》2021,22(7)
The Na/K-ATPase is the specific receptor for cardiotonic steroids (CTS) such as ouabain and digoxin. At pharmacological concentrations used in the treatment of cardiac conditions, CTS inhibit the ion-pumping function of Na/K-ATPase. At much lower concentrations, in the range of those reported for endogenous CTS in the blood, they stimulate hypertrophic growth of cultured cardiac myocytes through initiation of a Na/K-ATPase-mediated and reactive oxygen species (ROS)-dependent signaling. To examine a possible effect of endogenous concentrations of CTS on cardiac structure and function in vivo, we compared mice expressing the naturally resistant Na/K-ATPase α1 and age-matched mice genetically engineered to express a mutated Na/K-ATPase α1 with high affinity for CTS. In this model, total cardiac Na/K-ATPase activity, α1, α2, and β1 protein content remained unchanged, and the cardiac Na/K-ATPase dose–response curve to ouabain shifted to the left as expected. In males aged 3–6 months, increased α1 sensitivity to CTS resulted in a significant increase in cardiac carbonylated protein content, suggesting that ROS production was elevated. A moderate but significant increase of about 15% of the heart-weight-to-tibia-length ratio accompanied by an increase in the myocyte cross-sectional area was detected. Echocardiographic analyses did not reveal any change in cardiac function, and there was no fibrosis or re-expression of the fetal gene program. RNA sequencing analysis indicated that pathways related to energy metabolism were upregulated, while those related to extracellular matrix organization were downregulated. Consistent with a functional role of the latter, an angiotensin-II challenge that triggered fibrosis in the α1r/rα2s/s mouse failed to do so in the α1s/sα2s/s. Taken together, these results are indicative of a link between circulating CTS, Na/K-ATPase α1, ROS, and physiological cardiac hypertrophy in mice under baseline laboratory conditions. 相似文献
9.
We address the problem of adaptive output-feedback stabilization of general first-order hyperbolic partial integro-differential equations (PIDE). Such systems are also referred to as PDEs with non-local (in space) terms. We apply control at one boundary, take measurements on the other boundary, and allow the system’s functional coefficients to be unknown. To deal with the absence of both full-state measurement and parameter knowledge, we introduce a pre-transformation (which happens to be based on backstepping) of the system into an observer canonical form. In that form, the problem of adaptive observer design becomes tractable. Both the parameter estimator and the control law employ only the input and output signals (and their histories over one unit of time). Prior to presenting the adaptive design, we present the non-adaptive/baseline controller, which is novel in its own right and facilitates the understanding of the more complex, adaptive system. The parameter estimator is of the gradient type, based on a parametric model in the form of an integral equation relating delayed values of the input and output. For the closed-loop system we establish boundedness of all signals, pointwise in space and time, and convergence of the PDE state to zero pointwise in space. We illustrate our result with a simulation. 相似文献
10.
Pierre Colomb Alexis Irlande Olivier Raynaud Yoan Renaud 《Annals of Mathematics and Artificial Intelligence》2014,70(1-2):107-122
A collection of sets on a ground set U n (U n ?=?{1,2,...,n}) closed under intersection and containing U n is known as a Moore family. The set of Moore families for a fixed n is in bijection with the set of Moore co-families (union-closed families containing the empty set) denoted ${\mathbb{M}}_n$ . This paper follows the work initiated in Colomb et al. (Ann Math Artif Intell 67(2):109–122, 2013) in which we have given an inductive definition of the lattice of Moore co-families. In the present paper we use this definition to define a recursive decomposition tree of any Moore co-family and we design an original algorithm to compute the closure under union of any family. Then we compare performance of this algorithm to performance of Ganter’s algorithm and Norris’ algorithm. 相似文献