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101.
M Nieda A Nicol A Kikuchi K Kashiwase K Taylor K Suzuki K Tadokoro T Juji 《Canadian Metallurgical Quarterly》1998,91(3):977-983
The role of T lymphocytes in the control of chronic myeloid leukemia (CML) after bone marrow transplantations has been clearly shown. This effect closely correlates with graft-versus-host disease (GVHD). A specific graft-versus-leukemia (GVL) effect separate from GVHD has been postulated but has been difficult to show. One possible target for specific GVL activity is the bcr-abl fusion protein characteristic of CML. We have investigated the use of normal peptide-pulsed dendritic cells for the generation of cytotoxic, bcr-abl-specific T cells from normal donors. T cells (CD3+, CD8+, TCR alpha beta+, and NK receptor-negative) generated from a normal donor (HLA A24, B52, B59, Cw1) after stimulation with autologous dendritic cells, primed with a 16 mer peptide spanning the b3a2 breakpoint of bcr-abl, lysed CML cells from the peripheral blood of seven patients with CML with the b3a2 breakpoint. CML cells from four patients with only the b2a2 breakpoint were not lysed. Phytohemagglutinin (PHA) blasts derived from peripheral blood of patients with CML were not lysed, suggesting that cytotoxicity was not due to alloreactivity. Blocking experiments with anti-HLA-A,B,C indicated that cytotoxicity was dependent on recognition of major histocompatibility complex (MHC) class I molecules, although cytotoxicity was not MHC-restricted because not all patients shared HLA types with the T-cell donor. Specificity for bcr-abl and absence of alloreactivity was confirmed by the presence of lytic activity against autologous and allogeneic class I HLA-A matched monocytes pulsed with the 16 mer bcr-abl fusion peptide, but not against unpulsed monocytes or monocytes pulsed with other peptides. These results show that bcr-abl-specific T cells with marked cytotoxic activity against CML cells can be generated and amplified from normal donor peripheral blood. Recognition of HLA molecules is essential for cytotoxicity but strict HLA identity is not required. 相似文献
102.
KJ Crossley MB Nicol JJ Hirst DW Walker GD Thorburn 《Canadian Metallurgical Quarterly》1997,9(8):767-773
The high rate of progesterone synthesis by the placenta in late gestation exposes the ovine fetus to high concentrations of progesterone and its metabolites that may affect activity of the fetal brain. The aim of this study was to determine the effect of inhibiting maternal progesterone synthesis on sleep-wake activity in fetal sheep. Fetal and maternal vascular catheters, a fetal tracheal catheter, and electrodes for recording fetal electrocortical (ECoG), electro-ocular (EOG) and nuchal muscle electromyographic (EMG) activity were implanted. At 128-131 days gestation, progesterone production was inhibited by an injection of trilostane (50 mg), a 3beta-hydroxysteroid dehydrogenase inhibitor. Vehicle solution or progesterone (3 mg h(-1)) was then infused into the ewe between 6 and 12 h after the trilostane treatment. Maternal progesterone concentrations were significantly reduced from 1-24 h after trilostane treatment (P < 0.05) when followed by vehicle infusion. Fetal breathing movements (FBM), EOG, nuchal muscle EMG, and behavioural arousal increased 12 h after trilostane treatment (P < 0.05). In contrast, there was no change in fetal arousal, EOG, EMG or FBM activities when progesterone was infused after the trilostane treatment. These findings show that progesterone can influence fetal behaviour, and indicates that normal progesterone production tonically suppresses arousal, or wakefulness in the fetus. 相似文献
103.
104.
We have investigated purely gravitational membrane solutions to the Ho?ava nonrelativistic theory of gravity with detailed balance in 3 + 1 dimensions. We find that for arbitrary values of the running parameter λ > 1/3 there exist two branches of membrane solutions, and that in the special case λ = 1 one of them is degenerate, the lapse function being undetermined. For negative values of the cosmological constant, the solution contains a single membrane sitting at the center of space, which extends infinitely in the transverse direction, approaching a Lifshitz metric. For positive values of the cosmological constant, the solution represents a space that is bounded in the transverse direction, with two parallelmembrane-like or point-like singularities sitting at each of the boundaries. 相似文献
105.
Stability analysis of nonholonomic multiagent coordinate‐free formation control subject to communication delays 下载免费PDF全文
Antonio González Rosario Aragüés Gonzalo López‐Nicolás Carlos Sagüés 《国际强度与非线性控制杂志
》2018,28(14):4121-4138
》2018,28(14):4121-4138
This paper investigates the convergence of nonholonomic multiagent coordinate‐free formation control to a prescribed target formation subject to communication delays by means of Lyapunov‐Krasovskii approach and smooth state‐feedback control laws. As a result, an iterative algorithm based on linear matrix inequalities is provided to obtain the worst‐case point‐to‐point delay under which the multiagent system is guaranteed to be stable. It is worth mentioning that: (i) the given algorithm holds for any connected communication topology and (ii) the formation control is coordinate‐free, that is, a common frame is not required to be shared between agents. The effectiveness of the given method is illustrated through simulation results. 相似文献
106.
Nicolò Razza Micaela Castellino Marco Sangermano 《Journal of Materials Science》2017,52(23):13444-13454
Faster and simpler methods for the fabrication of Janus particles are of tremendous importance for a real implementation of these particles. By combining thiol-modified silica particles (SMPs) with the use of UV light, it is possible to rapidly fabricate Janus particles coated with polymer brushes and gold nanoparticles via photochemical emulsion-assisted route. From the silica particle surface, polymeric brushes of polyethylene(glycol), PEG, were grafted via a photografting-from method on one hemisphere by using the thiol groups as photoinitiator of the polymerization. The other hemisphere was coated with gold nanoparticles (AuNPs) generated in situ via photoreduction of chloroauric acid promoted by Norrish type I photoinitiator. PEG/AuNPs@SMPs coated with Au nanoparticles with average diameter of 12.7 or 22.5 nm were obtained by playing on the mass ratio between thiol-modified silica particles and gold precursor. The Janus PEG/AuNPs@SMPs were fully characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and UV–Vis spectroscopy. This strategy merges the advantages of emulsion-based selective masking and UV-induced reactions, and it is proved to be a feasible and fast route (reactions are completed in dozens of minutes) for Janus particles fabrication. 相似文献
107.
More than 5 years after their emergence, altmetrics are still seen as a promise to complement traditional citation-based indicators. However, no study has focused on their potential usefulness to capture the impact of scholarly books. While recent literature shows that citation indicators cannot fully capture the impact of books, other studies have suggested alternative indicators such as usage, publishers’ prestige or library holdings. In this paper, we calculate 18 indicators which range from altmetrics to library holdings, views, downloads or citations to the production of monographs of a Spanish university using the bibliometric suite PlumX from EBSCO. The objective of the study is to adopt a multidimensional perspective on the analysis of books and understand the level of complementarity between these different indicators. Also, we compare the overview offered by this range of indicators when applied to monographs with the traditional bibliometric perspective focused on journal articles and citation impact. We observe a low presence of altmetric indicators for monographs, even lower than for journal articles and a predominance of library holdings, confirming this indicator as the most promising one towards the analysis of the impact of books. 相似文献
108.
This article presents a novel band‐pass filter topology, based on the half‐mode substrate integrated waveguide (HMSIW), which allows for the simple design and easy manufacturing of filters with different bandwidth and number of poles. The design strategy, based on the modification of HMSIW cavity modes, is discussed in the case of two‐pole and four‐pole filters, and two prototypes are implemented and experimentally verified. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:72–79, 2016. 相似文献
109.
110.
Juan Gómez-Luna José María González-Linares José Ignacio Benavides Nicolás Guil 《Machine Vision and Applications》2013,24(5):899-908
A histogram is a compact representation of the distribution of data in an image with a full range of applications in diverse fields. Histogram generation is an inherently sequential operation where every pixel votes in a reduced set of bins. This makes finding efficient parallel implementations very desirable but challenging, because on graphics processing units thousands of threads may be atomically updating a short number of histogram bins. Under these circumstances, collisions among threads will be very frequent and such collisions will serialize thread execution, seriously damaging the performance. In this paper we propose a highly optimized approach to histogram calculation, which tackles such performance bottlenecks. It uses histogram replication for eliminating position conflicts, padding to reduce bank conflicts, and an improved access to input data called interleaved read access. Our so-called ${\mathcal{R}}$ -per-block approach to histogram calculation has been successfully compared to the main state-of-the-art works using four histogram-based image processing kernels and two real image databases. Results show that our proposal is between 1.4 and 15.7 faster than every previous implementation for histograms of up to 4,096 bins. 相似文献