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In node-positive breast carcinoma, the presence of tumour cells in the efferent vessels (EV) of the axillary nodes (positive EV status) was shown to be of poor prognosis in 1979. Later the presence of nodal micrometastases was also related to survival. This report describes a new subgroup in this system that is of potential therapeutic interest. It consisted of the 40% of the EV-positive cases with micrometastases (< 0.2 cm2) in their nodes, in addition to nodes with macrometastases. In them the difference in prognosis associated with EV status no longer held. Their prognosis did not differ markedly from that in the EV-negative patients. In the absence of such 'additional' micrometastases, the prognostic difference was still highly significant. There was also some indication that the presence of micrometastases consisting of embolic tumour growth alone may be associated with early death in EV-negative cases, in keeping with the prognosis in cases with lone micrometastases. 相似文献
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Josef G. Krammer 《The Journal of VLSI Signal Processing》1991,3(1-2):93-103
This paper deals with the parallel execution of algorithms with global and/or irregular data dependencies on a regularly and locally connected processor array. The associated communication problems are solved by the use of a two-dimensional sorting algorithm. The proposed architecture, which is based on a two-dimensional sorting network, offers a high degree of flexibility and allows an efficient mapping of many irregularly structured algorithms. In this architecture a one-dimensional processor array performs all required control and arithmetic operations, whereas the sorter solves complex data transfer problems. The storage capability of the sorting network is also used as memory for data elements. The algorithms for sparse matrix computations, fast Fourier transformation and for the convex hull problem, which are mapped onto this architecture, as well as the simulation of a shared-memory computer show that the utilization of the most complex components, the processors, is O(1). 相似文献
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Ohne Zusammenfassung 相似文献
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Software and Systems Modeling - Advances in model-based system engineering have greatly increased the predictive power of models and the analyses that can be run on them. At the same time, designs... 相似文献
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Domino Reactions in Organic Synthesis 总被引:1,自引:0,他引:1
Tietze LF 《Chemical reviews》1996,96(1):115-136