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排序方式: 共有674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.
Montanari D. Van Houdt J. Groeseneken G. Maes H.E. 《Solid-State Circuits, IEEE Journal of》1998,33(7):1090-1095
This paper presents a high-speed, small-area circuit specifically designed to identify the levels in the read out operation of a flash multilevel memory. The circuit is based on the analog computation of the Euclidean distance between the current read out from a memory cell and the reference currents that represent the different logic levels. An experimental version of the circuit has been integrated in a standard double-metal 0.7-μm CMOS process with a die area of only 140×100 μm2. Operating under a 5-V power supply, this circuit identifies the read-out current of a memory cell, and associates it with the appropriate logic level in 9 ns 相似文献
3.
Croon J.A. Rosmeulen M. Decoutere S. Sansen W. Maes H.E. 《Solid-State Circuits, IEEE Journal of》2002,37(8):1056-1064
In this paper, a physics-based mismatch model is presented. It is demonstrated on a 0.18-/spl mu/m technology that a simple mismatch model can still be used to characterize deep-submicron technologies. The accuracy of the model is examined and found to be within 20% in the strong inversion region. Bulk bias dependence is modeled in a physical way. To extract the mismatch parameters, a weighted fit is introduced. It is shown that the width and length dependence of the mismatch parameters is given by the Pelgrom model. 相似文献
4.
Classical parameter-extraction programs rely on the minimisation of the relative current deviation. However, since, especially for analogue applications, the slope of the IDS/VDS curve in the saturation region is at least equally important, a new fit strategy has been developed. This new fit strategy extracts a parameter set which optimises the current residual as well as the slope residual at every point. 相似文献
5.
V. Vassilev S. Thijs P. L. Segura P. Wambacq P. Leroux G. Groeseneken M. I. Natarajan H. E. Maes M. Steyaert 《Microelectronics Reliability》2005,45(2):255-268
This paper describes an approach to design ESD protection for integrated low noise amplifier (LNA) circuits used in narrowband transceiver front-ends. The RF constraints on the implementation of ESD protection devices are relaxed by co-designing the RF and the ESD blocks, considering them as one single circuit to optimise. The method is applied for the design of 0.25 μm CMOS LNA. Circuit protection levels higher than 3 kV HBM stress are achieved using conventional highly capacitive ggNMOS snapback devices. The methodology can be extended to other RF-CMOS circuits requiring ESD protection by merging the ESD devices in the functionality of the corresponding matching blocks. 相似文献
6.
Kerber A. Cartier E. Pantisano L. Degraeve R. Kauerauf T. Kim Y. Hou A. Groeseneken G. Maes H.E. Schwalke U. 《Electron Device Letters, IEEE》2003,24(2):87-89
The magnitude of the V/sub T/ instability in conventional MOSFETs and MOS capacitors with SiO/sub 2//HfO/sub 2/ dual-layer gate dielectrics is shown to depend strongly on the details of the measurement sequence used. By applying time-resolved measurements (capacitance-time traces and charge-pumping measurements), it is demonstrated that this behavior is caused by the fast charging and discharging of preexisting defects near the SiO/sub 2//HfO/sub 2/ interface and in the bulk of the HfO/sub 2/ layer. Based on these results, a simple defect model is proposed that can explain the complex behavior of the V/sub T/ instability in terms of structural defects as follows. 1) A defect band in the HfO/sub 2/ layer is located in energy above the Si conduction band edge. 2) The defect band shifts rapidly in energy with respect to the Fermi level in the Si substrate as the gate bias is varied. 3) The rapid energy shifts allows for efficient charging and discharging of the defects near the SiO/sub 2//HfO/sub 2/ interface by tunneling. 相似文献
7.
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
8.
Bellens R. de Schrijver E. Van den Bosch G. Groeseneken G. Heremans P. Maes H.E. 《Electron Devices, IEEE Transactions on》1994,41(3):413-419
A continued fast interface trap generation is observed in n-channel MOS transistors after termination of the hot-carrier stress. The magnitude of this post-stress effect is strongly dependent on the conditions of the preceding stress, on the post-stress conditions and on the process parameters. For measurements at 293 K, a simple model is proposed which is based on the release of hydrogen by the thermal detrapping of holes, and which can explain the observed dependencies. The importance of the post-stress Dit-generation is illustrated for the case of dynamic stress conditions where it can lead to an apparently deviating degradation behavior 相似文献
9.
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
10.
H Everaert A Maes AS Hambye L Mesotten L Mortelmans PR Franken 《Canadian Metallurgical Quarterly》1998,26(3):164-9; quiz 172-3
OBJECTIVE: After reading Part III of this series of nuclear cardiology articles, the technologist should be able to: (a) compare and contrast radiopharmaceuticals used for myocardial perfusion imaging; (b) describe imaging protocols used for detecting coronary artery disease; and (c) describe imaging patterns seen following reconstruction of myocardial images. 相似文献