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31.
NE Joseph C Fiocchi AD Levine 《Canadian Metallurgical Quarterly》1997,122(4):809-14; discussion 814-6
BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases, and their pathogenesis is attributed, in part, to alterations of the mucosal immune system. This study was designed to define the possible contribution of epithelial cells to the activation of lamina propria T lymphocytes (LPTs) in CD and UC. METHODS: LPTs isolated from CD, UC, and control surgical specimens were cocultured with freshly isolated allogeneic or autologous epithelial cells or epithelial cell lines. Resulting T-cell proliferation was evaluated by tritiated thymidine incorporation on day 5. RESULTS: When intestinal epithelial cells were used to stimulate mucosal T-cell proliferation, CD and UC LPTs were less responsive than control LPTs (p < 0.05 and p < 0.03, respectively). This difference between inflamed and control T cells was consistently observed by using a variety of different intestinal epithelial cell types. CONCLUSIONS: CD and UC mucosal T cells are hyporesponsive to activation by intestinal epithelial cells when compared with control LPTs. Elucidating the mechanism underlying the differential activation of CD and UC LPTs may help to better understand the immunopathogenesis of these conditions. 相似文献
32.
AJ Joseph 《Canadian Metallurgical Quarterly》1997,17(4):685-699
Conceptually, the Chest Pain Center model is nothing more than a system of delivering health care. It is a model that all hospitals can embrace as a framework for organizational decision making in meeting the heart-care needs of their communities. It also provides a framework for clinical decision making. By adopting some or all of the common features of the model, hospitals develop a common language, similar to what took place when CCUs first opened in the 1960s. Application of evidence-based clinical practice is promoted. Approaches that account for both clinical outcomes and financial outcomes will be further refined. One result will be simultaneous improvement in clinical outcomes and a decrease in costs, but the most important aspect of the Chest Pain Center model is that it puts the patient first. 相似文献
33.
Grens C.M. Cressler J.D. Andrews J.M. Qingqing Liang Joseph A.J. 《Electron Devices, IEEE Transactions on》2007,54(7):1605-1616
This paper presents a comprehensive picture of operating-voltage constraints in SiGe heterojunction bipolar transistors, addressing breakdown-related issues as they relate to technology generation, bias configuration, and operating-current density. New definitions for breakdown voltage, adopted from standard measurements, are presented. Practical design implications and physical origins of breakdown are explored using calibrated 2-D simulations and quasi-3-D compact models. Device-level analysis of ac instabilities and power performance, which is relevant to mixed-signal circuit design, is presented, and implications of the relaxed voltage constraints for common-base operation are explored. 相似文献
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35.
Responds to the comments by J. J. Kramer (see record 1990-58925-001) on the current author's original article (see record 1986-19878-001), in which Matarazzo contends that computerized clinical psychological test interpretations offer considerable potential for improving the work of health service providers. However, cost additions associated with this technology have increased the probabilities that legislative, judicial, and administrative restrictions and sanctions will be imposed. Here, Matarazzo notes that he finds nothing in Kramer's comments that is inconsistent with the opinions that Matarazzo himself offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Dr Joseph A. Cannataci 《AI & Society》1989,3(3):169-183
This paper examines some of the possible legal implications of the production, marketing and use of expert systems. The relevance of a legally useful definition of expert systems, comprising systems designed for use both by laymen and professionals, is related to the distinctions inherent in the legal doctrine underlying provision of goods and provision of services. The liability of the sellers and users of, and contributors to, expert systems are examined in terms of professional malpractice as well as product liability. A recurring theme indicates that legislators may be inclined to restrict possibilities of liability suits in order to avoid disincentives to the creation of expert systems. 相似文献
37.
The sludge from six SBRs treating dairy effluent and located at same geographical location, in North East of France, were collected to study their characteristic behavior. The six plants were designed and constructed by the same manufacturer and are working under quite similar operating conditions. The objective of the study was to observe if any similarity existed in the characteristics of the sludge collected from the SBRs. The sludge was characterized for morphological properties (filament index, floc size), settling, compressibility, suspended solids (SS) concentration. The sludge from each plant was different from the others in most of the characteristics. One sludge out of six (sludge G) was completely different from the others with a very degraded structure and low discrete settling and compression. This reactor was not working fully satisfactorily with a too high COD at outlet, probably because this SBR was undergoing repetitive overloading linked to a very bad recovery of the whey by the cheese maker. The five other SBRs were working fully satisfactorily but the characteristics of the five sludges were quite different from one sludge to another. The size of the flocs seemed to be the only parameter measured which could be correlated to the settling characteristics of the sludge. The sludge characteristics and the parameter correlations were also compared with that of municipal activated sludge and were found to be very different. 相似文献
38.
Microwave plasma synthesis of TiN and ZrN nanopowders 总被引:2,自引:0,他引:2
This work demonstrates that TiN and ZrN nanopowders can be prepared by microwave plasma synthesis method. The effects of flow rate of plasma forming gas, flow rate of carrier gas and feeding rate of precursor raw material to the average particle size were studied. The TiN and ZrN nanopowders were characterized by means of transmission electron microscopy (TEM) and X-ray diffraction (XRD). 相似文献
39.
40.
Logarithmic CMOS image sensors are appealing for their high-contrast and high-speed response but they require postprocessing to achieve high-quality images. Previously published work has explained the fixed pattern noise (FPN) in these image sensors using a steady-state analysis. This paper explains how the transient response of the readout circuit may also contribute to FPN. Thus, the performance of these CMOS cameras may be optimized with a proper understanding of the transient response, which is explained here through modeling and simulation with some experimental validation. In particular, the gain variation of a logarithmic camera is shown to be caused primarily by premature digitization. As logarithmic and linear active pixel sensors use similar circuits, some results in this paper, e.g., an analysis of readout capacitance, apply equally to the latter. 相似文献