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排序方式: 共有813条查询结果,搜索用时 46 毫秒
1.
Yanqing Ji Hao Ying John Yen Shizhuo Zhu Daniel C. Barth‐Jones Richard E. Miller R. Michael Massanari 《国际智能系统杂志》2007,22(8):827-845
Discovering unknown adverse drug reactions (ADRs) in postmarketing surveillance as early as possible is highly desirable. Nevertheless, current postmarketing surveillance methods largely rely on spontaneous reports that suffer from serious underreporting, latency, and inconsistent reporting. Thus these methods are not ideal for rapidly identifying rare ADRs. The multiagent systems paradigm is an emerging and effective approach to tackling distributed problems, especially when data sources and knowledge are geographically located in different places and coordination and collaboration are necessary for decision making. In this article, we propose an active, multiagent framework for early detection of ADRs by utilizing electronic patient data distributed across many different sources and locations. In this framework, intelligent agents assist a team of experts based on the well‐known human decision‐making model called Recognition‐Primed Decision (RPD). We generalize the RPD model to a fuzzy RPD model and utilize fuzzy logic technology to not only represent, interpret, and compute imprecise and subjective cues that are commonly encountered in the ADR problem but also to retrieve prior experiences by evaluating the extent of matching between the current situation and a past experience. We describe our preliminary multiagent system design and illustrate its potential benefits for assisting expert teams in early detection of previously unknown ADRs. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 827–845, 2007. 相似文献
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The techniques of Feulgen staining, acridine orange staining, and a sperm chromatin structure assay using acridine orange and flow cytometry were compared for selective examination of bovine sperm nuclei. Twenty frozen semen samples were simultaneously analysed by all three methods. The prevalence of abnormally condensed DNA and its relationship to other semen traits were determined in ejaculates from 70 bulbs presented for routine examination for breeding soundness and in frozen semen from 348 bulls evaluated over five years. A breeding trial with 118 beef heifers using semen from six bulls with different degrees of nuclear abnormalities was performed to assess the importance of the defects with respect to fertility. The results indicate that few spermatozoa with abnormal DNA condensation are found in normal semen, but the incidence increases with disturbance of spermatogenesis. However, high numbers of abnormally condensed nuclei were found in the absence of an increase in other defects. This nuclear defect might be at least partially of epididymal origin; it can lower fertility and can be compensated for by increasing the numbers of normal spermatozoa in the insemination dose. The percentage of abnormally condensed sperm nuclei as detected by Feulgen staining was significantly correlated with that detected by microscopy after acridine orange staining and by the sperm chromatin structure assay. We therefore consider the Feulgen technique to be a valuable tool for assessing the nuclear integrity of bovine spermatozoa. 相似文献
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Sijtze Stob Ruud M. Scheek Rolf Boelens Klaas Dukstra Robert Kaptein 《Israel journal of chemistry》1988,28(4):319-327
Photo-CIDNP is a useful technique to identify surface residues in proteins and to assign resonances in their 1H NMR spectra by the spectral simplification that is obtained. In spite of this simplification, conventional photo-CIDNP spectra can be quite complex due to spectral overlap. For this reason two-dimensional (2D) methods are welcome. We present combinations of photo-CIDNP with 2D J-correlated spectroscopy (CIDNP-COSY) and with 2D NOE spectroscopy (CIDNP-NOESY). In these experiments we insert a saturation pulse sequence and a short laser-irradiation period at the beginning of the preparation period to generate CIDNP, leaving the remaining of the pulse scheme essentially unaltered. The CIDNP-COSY and CIDNP-NOESY spectra of a hen egg-white (HEW) lysozyme are presented. The CIDNP-NOESY spectrum of lysozyme is compared with the results from 1D cross-polarisation experiments on the same protein. CIDNP-NOESY spectra of lysozyme with and without inhibitor NAG are compared. 相似文献
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Kris J. Kozaczek M.Sc. Clayton O. Ruud Ph.D. Joseph C. Conway Jr. Ph.D. Chin-Jye Yu B.S. Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1990,42(5):35-38
An advanced x-ray diffraction technique allows the development of texture components to be monitored and provides supplementary information about the cold work and residual stresses in cold-rolled copper sheet. The new technique confirms the results of an ultrasonic test, except for the ultrasonic test’s sensitivity to grain size. The new x-ray diffraction technique could be adapted to provide in-process, nondestructive evaluation of thin copper sheet, even for material moving at high speeds. 相似文献
10.
Mohammed Chahim Ruud Brekelmans Dick den Hertog Peter Kort 《Optimization methods & software》2013,28(3):458-477
This paper determines the optimal timing of dike heightenings as well as the corresponding optimal dike heightenings to protect against floods. To derive the optimal policy, we design an algorithm based on the Impulse Control Maximum Principle. In this way, this paper presents one of the first real-life applications of the Impulse Control Maximum Principle developed by Blaquière. We show that the proposed impulse control (IC) approach performs better than dynamic programming with respect to computational time. This is caused by the fact that IC does not need discretization in time. 相似文献