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A case of histologically confirmed Paget's disease of the breast in a 72 year old man, without underlying breast carcinoma, is reported. This report raises questions about the pathogenesis of this condition and suggests that Paget's disease is an independent, intraepidermal carcinoma rather than a direct extension of intraductal carcinoma of the breast to the nipple and areola.  相似文献   
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Rectal and axillary temperatures were measured simultaneously in 83 children using three different thermometer devices providing 166 pairs of results. In the first series consisting of 22 febrile children (44 measurements) and 20 afebrile children (40 measurements), the rectal mercury measurement was compared to an axillary mercury and axillary Tempa-DOT thermometer. The axillary mercury had sensitivity of 14/22 (64%) and specificity of 20/20 (100%) while the Tempa-DOT had sensitivity of 15/22 (68%) and specificity of 19/20 (95%). In the second series comprising 21 febrile children (42 measurements) and 20 afebrile children (40 measurements) the axillary mercury had sensitivity of 11/21 (52%) and specificity of 20/20 (100%) while the electronic thermometer had sensitivity of 10/21 (48%) and specificity of 20/20 (100%). Regardless of the thermometer used, the axilla is a poor alternative to rectal measurements in the diagnosis of fever. CONCLUSION: Mercury-free thermometers, when used in the axilla are as poor alternatives to rectal measurements as mercury-in-glass thermometers.  相似文献   
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BACKGROUND: Hydrogen exchange labelling has been a key method in characterizing the structure of transient folding intermediates. In studies of several proteins, however, there has been clear spectroscopic evidence for partial folding of some kind at very early times, before any protection from exchange was measurable. These results, presumably a consequence of limited stability of specific backbone interactions, have made it difficult to assess the extent of native-like folding in the very early intermediates. We have used a variant of the labelling method to investigate marginally stable structures formed within the first few milliseconds of refolding of two such proteins, hen lysozyme and ubiquitin. RESULTS: In lysozyme, population of a subset of native-like secondary structures on this timescale is revealed, thus reconciling the exchange behaviour with circular dichroism measurements and confirming the significance of the rapidly formed embryonic structure as a foundation for the subsequent folding pathway. In the case of ubiquitin, by contrast, no significantly protective structure was detectable, suggesting that here secondary structural elements can be populated only marginally ahead of the major cooperative folding event; this was also supported by stopped-flow circular dichroism measurements. CONCLUSIONS: The hydrogen exchange approach can be extended to probe the formation of native-like structure formed in very early folding intermediates, even when the stability of specific interactions is marginal. In the case of lysozyme, this has provided a new window on an early stage of organization of the alpha-helical domain.  相似文献   
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Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) is an analytical technique for real-time quantification of trace gases in air or breath samples. SIFT-MS system thus offers unique potential for early, rapid detection of disease states. Identification of volatile organic compound (VOC) masses that contribute strongly towards a successful classification clearly highlights potential new biomarkers. A method utilising kernel density estimates is thus presented for classifying unknown samples. It is validated in a simple known case and a clinical setting before-after dialysis. The simple case with nitrogen in Tedlar bags returned a 100% success rate, as expected. The clinical proof-of-concept with seven tests on one patient had an ROC curve area of 0.89. These results validate the method presented and illustrate the emerging clinical potential of this technology.  相似文献   
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嵌入式系统大屏幕LED点阵显示器   总被引:1,自引:1,他引:1  
戴峻峰 《现代电子技术》2004,27(19):68-69,72
本系统的设计思路是:用单片机对整个系统进行总体控制。其中显示字模数据由单片机输入显存,点阵的点亮过程由其他电路自动完成。其特点是:点阵的动态显示过程不占用CPU的时间,这就使CPU能更有效地控制管理其他设备的工作流程。  相似文献   
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