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91.
E Elstner M Linker-Israeli J Le T Umiel P Michl JW Said L Binderup JC Reed HP Koeffler 《Canadian Metallurgical Quarterly》1997,99(2):349-360
Patients with acute promyelocytic leukemia (APL) usually relapse after all-trans retinoic acid (RA) treatment because this therapy fails to eradicate the malignant clone. Our data showed that KH 1060 and other 20-epi vitamin D3 analogs alone were potent inhibitors of clonal growth of NB4 cells, an APL cell line (ED50, approximately 5 x 10(-11) M). The combination of KH 1060 and 9-cis-RA synergistically and irreversibly enhanced this effect. Neither KH 1060 nor 9-cis-RA (10(-6) M, 3 d) were strong inducers of differentiation of NB4 cells. However, 98% of the cells underwent differentiation to a mature phenotype with features of both granulocytes and monocytes after exposure to a combination of both compounds. Apoptosis only increased after incubation of NB4 cells with 9-cis-RA alone (28%) or with a combination of 9-cis-RA plus KH1060 (32%). Immunohistochemistry showed that the bcl-2 protein decreased from nearly 100% of the wild-type NB4 cells to 2% after incubation with a combination of KH 1060 and 9-cis-RA, and the bax protein increased from 50% of wild-type NB4 cells to 92% after culture with both analogs (5 x 10(-7) M, 3 d). Western blot analysis paralleled these results. Studies of APL cells from one untreated individual paralleled our results with NB4 cells. Taken together, the data demonstrated that nearly all of the NB4 cells can be irreversibly induced to differentiate terminally when exposed to the combination of KH 1060 and 9-cis-RA. 相似文献
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93.
VI Korol''kov VP Krotov V Konvertino P Le?tem EV Trambovetski? J Fanton R Krisman IuV Gordeev D Evert AM Nosovski? J Konnolli 《Canadian Metallurgical Quarterly》1998,32(3):30-37
Medical practice guidelines are being developed rapidly and advocated as a crucial component in transforming and improving the delivery of health care services. However, little is known about the ability of hospitals to institute guidelines outside of experimental settings. This article approaches guideline implementation from the viewpoint of process innovation assimilation and presents specific recommendations for organizational tactics leading to successful implementation of practice guidelines. 相似文献
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96.
Kuo R. J. Chang C. K. Nguyen Thi Phuong Quyen Liao T. W. 《Knowledge and Information Systems》2021,63(7):1935-1959
Knowledge and Information Systems - With the advance of information technology, many fields have begun using data clustering to reveal data structures and obtain useful information. Most of the... 相似文献
97.
Tuan Hue Thi Li Cheng Jian Zhang Li Wang Shinichi Satoh 《Computer Vision and Image Understanding》2012,116(3):378-395
In this paper, we propose a framework for human action analysis from video footage. A video action sequence in our perspective is a dynamic structure of sparse local spatial–temporal patches termed action elements, so the problems of action analysis in video are carried out here based on the set of local characteristics as well as global shape of a prescribed action. We first detect a set of action elements that are the most compact entities of an action, then we extend the idea of Implicit Shape Model to space time, in order to properly integrate the spatial and temporal properties of these action elements. In particular, we consider two different recipes to construct action elements: one is to use a Sparse Bayesian Feature Classifier to choose action elements from all detected Spatial Temporal Interest Points, and is termed discriminative action elements. The other one detects affine invariant local features from the holistic Motion History Images, and picks up action elements according to their compactness scores, and is called generative action elements. Action elements detected from either way are then used to construct a voting space based on their local feature representations as well as their global configuration constraints. Our approach is evaluated in the two main contexts of current human action analysis challenges, action retrieval and action classification. Comprehensive experimental results show that our proposed framework marginally outperforms all existing state-of-the-arts techniques on a range of different datasets. 相似文献
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针对目前网络地理信息系统体系结构难以实现Internet环境下的异构空间信息的互操作问题,深入分析其主要原因,在对现有网络地理信息系统的三层体系结构进行深入分析的基础上,提出一种基于Web services的网络地理信息系统体系结构(Web-based geographical information services visualization architecture,WebGISVisA).WebGISVisA体系结构通过Web services对各个地理信息系统组件进行包装,实现各个组件的跨平台操作,从技术上使得客户端和服务端达到了负载平衡,完成了WebGIS三维的虚拟现实,实现了在Internet下空间数据互操作和跨平台的功能,最大限度地达到数据共享. 相似文献
100.
The mobile wireless market has been attracting many customers. Technically, the paradigm of anytime-anywhere connectivity raises previously unthinkable challenges, including the management of million of mobile customers, their profiles, the profiles-based selective information dissemination, and server-side computing infrastructure design issues to support such a large pool of users automatically and intelligently. In this paper, we propose a data mining technique for discovering frequent behavioral patterns from a collection of trajectories gathered by Global Positioning System. Although the search space for spatiotemporal knowledge is extremely challenging, imposing spatial and temporal constraints on spatiotemporal sequences makes the computation feasible. Specifically, the mined patterns are incorporated with synthetic constraints, namely spatiotemporal sequence length restriction, minimum and maximum timing gap between events, time window of occurrence of the whole pattern, inclusion or exclusion event constraints, and frequent movement patterns predictive of one ore more classes. The algorithm for mining all frequent constrained patterns is named cAllMOP. Moreover, to control the density of pattern regions a clustering algorithm is exploited. The proposed method is efficient and scalable. Its efficiency is better than that of the previous algorithms AllMOP and GSP with respect to the compactness of discovered knowledge, execution time, and memory requirement. 相似文献