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排序方式: 共有221条查询结果,搜索用时 31 毫秒
101.
P Solal-Céligny E Lepage N Brousse CL Tendler P Brice C Ha?oun J Gabarre B Pignon G Tertian R Bouabdallah JF Rossi C Doyen B Coiffier 《Canadian Metallurgical Quarterly》1998,16(7):2332-2338
PURPOSE: To compare progression-free survival (PFS), overall survival (OS), and toxicity of a doxorubicin-containing regimen administered alone or in combination with interferon alfa-2b (IFNalpha) in patients with low-grade follicular lymphoma (FL) and poor prognostic factors. PATIENTS AND METHODS: Two hundred sixty-eight patients with advanced-stage FL received cyclophosphamide, doxorubicin, teniposide, and prednisone (CHVP) monthly for 6 months, then every 2 months for 12 months. After randomization, 242 patients were evaluated for efficacy: 119 received CHVP alone, and 123 also received IFNalpha at a dose of 5 million units three times weekly for 18 months. RESULTS: After a 6-year median follow-up, the patients treated with CHVP + IFNalpha showed significantly longer median PFS than those who received CHVP alone (2.9 years v 1.5 years, respectively; P = .0002) and significantly longer median OS (not reached v 5.6 years, respectively; P = .008). Although some side effects, which included neutropenia, asthenia, fever, elevated serum transaminase levels, flu-like symptoms, and thrombocytopenia, were more frequently observed in patients who received the combination regimen, these reactions were moderate. IFNalpha was withdrawn because of toxicity in 10% of the patients, and a dosage reduction or temporary suspension was required in 28%. CONCLUSION: With long-term follow-up of 6 years, these results confirm that the addition of IFNalpha to a doxorubicin-containing regimen for patients with advanced-stage and clinically aggressive FL not only increased PFS, as in most other similar trials, but also prolonged OS. Toxicity was moderate. The beneficial effects of this combined chemotherapy and IFNalpha regimen on OS probably reflect the selection of FL patients with poor prognostic factors. 相似文献
102.
Brice Nédelec Julian Tanke Davide Frey Pascal Molli Achour Mostéfaoui 《World Wide Web》2018,21(3):629-661
Peer-sampling protocols constitute a fundamental mechanism for a number of large-scale distributed applications. The recent introduction of WebRTC facilitated the deployment of decentralized applications over a network of browsers. However, deploying existing peer-sampling protocols on top of WebRTC raises issues about their lack of adaptiveness to sudden bursts of popularity over a network that does not manage addressing or routing. Spray is a novel random peer-sampling protocol that dynamically, quickly, and efficiently self-adapts to the network size. Our experiments show the flexibility of Spray and highlight its efficiency improvements at the cost of small overhead. We embedded Spray in a real-time decentralized editor running in browsers and ran experiments involving up to 600 communicating Web browsers. The results demonstrate that Spray significantly reduces the network traffic according to the number of participants and saves bandwidth. 相似文献
103.
Brice Mora Michael A. Wulder Geordie W. Hobart Joanne C. White Christopher W. Bater Francois A. Gougeon 《International journal of remote sensing》2013,34(12):4406-4424
Many areas of forest across northern Canada are challenging to monitor on a regular basis as a result of their large extent and remoteness. Although no forest inventory data typically exist for these northern areas, detailed and timely forest information for these areas is required to support national and international reporting obligations. We developed and tested a sample-based approach that could be used to estimate forest stand height in these remote forests using panchromatic Very High Spatial Resolution (VHSR, < 1 m) optical imagery and light detection and ranging (lidar) data. Using a study area in central British Columbia, Canada, to test our approach, we compared four different methods for estimating stand height using stand-level and crown-level metrics generated from the VHSR imagery. ‘Lidar plots’ (voxel-based samples of lidar data) are used for calibration and validation of the VHSR-based stand height estimates, similar to the way that field plots are used to calibrate photogrammetric estimates of stand height in a conventional forest inventory or to make empirical attribute estimates from multispectral digital remotely sensed data. A k-nearest neighbours (k-NN) method provided the best estimate of mean stand height (R 2 = 0.69; RMSE = 2.3 m, RMSE normalized by the mean value of the estimates (RMSE-%) = 21) compared with linear regression, random forests, and regression tree methods. The approach presented herein demonstrates the potential of VHSR panchromatic imagery and lidar to provide robust and representative estimates of stand height in remote forest areas where conventional forest inventory approaches are either too costly or are not logistically feasible. While further evaluation of the methods is required to generalize these results over Canada to provide robust and representative estimation, VHSR and lidar data provide an opportunity for monitoring in areas for which there is no detailed forest inventory information available. 相似文献
104.
Benoît Charlot Gilbert Sassine Alexandra Garraud Brice Sorli Alain Giani Philippe Combette 《Microsystem Technologies》2013,19(6):895-903
PEDOT:PSS is a conductive polymer that is used as electrodes in organic electronic devices, but also in neuronal probes and implantable devices. This material can also be used for building deformable electrodes in soft substrates for several sensing applications. However, this material being sensitive to several chemicals and moisture it is difficult to pattern microstructures using standard lithography techniques. This paper will review and show some techniques developed for patterning PEDOT:PSS thin films using both soft lithography, such as microcontact printing and shadow masking, and conventional lithography techniques. In addition of this review we present a new lithography technique using silicon nitride protection layer and an analysis and comparison of ICP RIE dry plasma etch rates of PEDOT:PSS with different gases. 相似文献
105.
Shuzhi Sam Ge Qun Zhang Aswin Thomas Abraham Brice Rebsamen 《Robotics and Autonomous Systems》2011,59(3-4):228-242
In this paper, a novel approach, Simultaneous Path Planning and Topological Mapping (SP2ATM), is presented to address the problem of path planning in unknown environments by concurrent and incremental construction of a map, which strictly exploits only the topology rather than grid representation. For local topological information representation, a new concept, Admissible Space Tree (AST), is presented to describe the admissible free space in the environment as a group of nodes and graphs. The global map of the explored environment is encoded in a Hierarchical Topological Map (HTM), which by embedding the AST, serves as the least information to facilitate path planning. For simplicity, the algorithm is implemented in a planar space on our differentially driven mobile robot X1, based on its range sensing and self-localization capabilities. Experiments’ results show that SP2ATM is effective and globally convergent in complex and dynamic environments. 相似文献
106.
Lars M. Kristensen Peter Mechlenborg Lin Zhang Brice Mitchell Guy E. Gallasch 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(1):5-14
This paper shows how a formal method in the form of Coloured Petri Nets (CPNs) and the supporting CPN Tools have been used
in the development of the Course of Action Scheduling Tool (COAST). The aim of COAST is to support human planners in the specification
and scheduling of tasks in a Course of Action. CPNs have been used to develop a formal model of the task execution framework
underlying COAST. The CPN model has been extracted in executable form from CPN Tools and embedded directly into COAST, thereby
automatically bridging the gap between the formal specification and its implementation. The scheduling capabilities of COAST
are based on state space exploration of the embedded CPN model. Planners interact with COAST using a domain-specific graphical
user interface (GUI) that hides the embedded CPN model and analysis algorithms. This means that COAST is based on a rigorous
semantical model, but the use of formal methods is transparent to the users. Trials of operational planning using COAST have
been conducted within the Australian Defence Force.
The work of Lin Zhang was done while he was with the Command and Control Division of the Australian Defence Science and Technology
Organisation. 相似文献
107.
Ivira B Fillit RY Ndagijimana F Benech P Parat G Ancey P 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(1):139-147
The present work first provides an experimental technique to study self-heating of bulk acoustic wave (BAW) resonators under high RF power in the gigahertz range. This study is specially focused on film bulk acoustic wave resonators and solidly mounted resonators processed onto silicon wafers and designed for wireless systems. Precisely, the reflection coefficient of a one-port device is measured while up to several watts are applied and power leads to electrical drifts of impedances. In the following, we describe how absorbed power can be determined from the incident one in real time. Therefore, an infrared camera held over the radio frequency micro electromechanical system (RF-MEMS) surface with an exceptional spatial resolution reaching up to 2 microm/pixels gives accurate temperature mapping of resonators after emissivity correction. From theoretical point of view, accurate three-dimensional (3-D) structures for finite-element modeling analyses are carried out to know the best materials and architectures to use for enhancing power handling. In both experimental and theoretical investigations, comparison is made between film bulk acoustic wave resonators and solidly mounted resonators. Thus, the trend in term of material, architecture, and size of device for power application such as in transmission path of a transceiver is clearly identified. 相似文献
108.
Jean-François Brice René Gérardin Abdallah El Maslout Michel Zanne Alain Courtois Jacques Aubry 《Materials Research Bulletin》1975,10(11):1243-1248
The phosphidation of beryllium in the presence of traces of hydrogen leads to non stoichiometric ternary phases BeP2?xHy. The stoichiometric diphosphide BeP2 cannot be obtained. The hydrogenated phases are black and non hygroscopic. The structural study with X rays diffraction, neutrons diffraction, electronic microdiffraction, as well as the crystallographic data from single crystal, provide evidence for a quadratic cell with & . The stacking is diamond type when considering all the atoms : Be, P and H. 相似文献
109.
Fast oscillations and in particular gamma-band oscillation (20-80 Hz) are commonly observed during brain function and are at the center of several neural processing theories. In many cases, mathematical analysis of fast oscillations in neural networks has been focused on the transition between irregular and oscillatory firing viewed as an instability of the asynchronous activity. But in fact, brain slice experiments as well as detailed simulations of biological neural networks have produced a large corpus of results concerning the properties of fully developed oscillations that are far from this transition point. We propose here a mathematical approach to deal with nonlinear oscillations in a network of heterogeneous or noisy integrate-and-fire neurons connected by strong inhibition. This approach involves limited mathematical complexity and gives a good sense of the oscillation mechanism, making it an interesting tool to understand fast rhythmic activity in simulated or biological neural networks. A surprising result of our approach is that under some conditions, a change of the strength of inhibition only weakly influences the period of the oscillation. This is in contrast to standard theoretical and experimental models of interneuron network gamma oscillations (ING), where frequency tightly depends on inhibition strength, but it is similar to observations made in some in vitro preparations in the hippocampus and the olfactory bulb and in some detailed network models. This result is explained by the phenomenon of suppression that is known to occur in strongly coupled oscillating inhibitory networks but had not yet been related to the behavior of oscillation frequency. 相似文献
110.