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Homans  AC; Forman  EN; Barker  BE 《Blood》1985,66(6):1321-1325
The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL.  相似文献   
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A study was undertaken to investigate the response of the rodent somatosensory barrel cortex to single-whisker, near-threshold vibrissal stimuli. Cortical responses to controlled whisker deflections were recorded by (i) conventional multi-unit extracellular recording within the cytochrome oxidase rich barrels centers and the interbarrel septa, and (ii) intrinsic signal optical imaging, a technique that provides a spatial view of cortical activation thought to be related to the deoxygenation of hemoglobin in activated areas. Barrel cortex neurons responded weakly to whisker deflections of 0.04 degrees. Their response to a series of small stimuli of increasing amplitude was well-fitted by a logarithmic function. Responses to larger stimuli declined monotonically with distance from the center of the barrel column, and were characterized by greater onset and offset firing rates, by greater post-excitatory reduction of firing to below spontaneous levels, and by shorter response latency. In comparison to measurements taken previously from primary vibrissal afferent fibers, we conclude that cortical cells can respond to activity in a very small fraction of first-order sensory neurons.   相似文献   
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Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented.  相似文献   
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Multiple sequence alignment (MSA) is a vital problem in biology. Optimal alignment of multiple sequences becomes impractical even for a modest number of sequences [1] since the general version of the problem is NP-hard. Because of the high time complexity of traditional MSA algorithms, even today's fast computers are not able to solve the problem for large number of sequences. In this paper we present a randomized algorithm to calculate distance matrices, which is a major step in many multiple sequence alignment algorithms. The basic idea employed is sampling (along the lines of [2]). We also illustrate how to parallelize this algorithm. In Section 1 we introduce the problem of multiple sequence alignments. In Section 2 we provide a discussion on various methods that have been employed in the literature for Multiple Sequence Alignment. In this section we also introduce our new sampling approach. We extend our randomized algorithm to the case of non-uniform length sequences as well. We show that our algorithms are amenable to parallelism in Section 3. In Section 4 we back up our claim of speedup and accuracy with empirical data and examples. In Section 5 we provide some concluding remarks.  相似文献   
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Taking into account real life patient care in Germany and by international comparison, the indication assessment and performance of peripheral angioplasty is as an integral part of comprehensive patient care substantially in the fields of cardiology and angiology. As peripheral arterial disease (PAD) is often associated with systemic atherosclerosis, which may involve the whole arterial vascular system and considering resulting points of interference in both vascular diagnostics and therapy, the establishment of an interdisciplinary vascular conference within the clinic is recommended to assure optimal patient care and patient management. In order to improve medical further training in cardiology and angiology as well as for the implementation of the actual reality of patient care, there is an urgent need for adaption of the further education catalogue for cardiology and angiology by inclusion of peripheral angioplasty.  相似文献   
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