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Goodpasture syndrome is an often fatal autoimmune disease associated with glomerulonephritis and/or pulmonary hemorrhage. The clinical manifestations of this disease correlate well with the presence of circulating antiglomerular basement membrane (GBM) autoantibodies. The primary target antigen in glomerular and alveolar basement membranes is thought to be the alpha 3 chain of type IV collagen. Nearly all that is known about anti-GBM antibodies in humans comes from work on unbound circulating antibody. We recently had the unique and rare opportunity to obtain early postmortem antibody and tissues from a patient who died with catastrophic Goodpasture syndrome. The specificity of circulating, kidney-bound and lung-bound autoantibodies from this patient was evaluated against a variety of purified basement membrane constituents. The results indicate that the primary target for the circulating and tissue-bound autoantibodies is the NC1 domain of the alpha 3(IV) chain of type IV collagen. Additionally, all the antibodies recognize a cryptic epitope/s on the alpha 3(IV)NC1 hexamer. Furthermore, tissue-bound and circulating antibodies compete with one another for overlapping epitopes on the antigen. These findings demonstrate that circulating autoantibodies in Goodpasture syndrome are highly representative of those bound to organ tissues, strengthening the notion that pathogenic autoantibodies are targeted to the alpha 3(IV)NC1 collagen, and that previous reports of findings in the circulation may be applicable to tissue injury.  相似文献   
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An apparatus was developed wherein a vacuum source was used to pull air across a controlled-release-formulation dispenser or a planchet containing a known quantity of a semiochemical and into a collector filled with a polymeric adsorbent. After a set time, the semiochemical was eluted with solvent and was quantified by gas-liquid chromatography (GLC). High percentages of known quantities of the lepidopteran semiochemicals (Z)-7-dodecen-l -ol acetate (Z7DDA), boiling point (bp) 275 ° C/1 atm, (Z)-9-tetradecen-1-ol formate (Z9TDF), bp 289 °C/1 atm, and (Z,Z)-3,13-octadecadien-1-ol acetate (ZZODDA), bp 490 °C/1 atm, were recovered. The semiochemicals did not oxidize and were recovered quantitatively from the adsorbent. The release rates of Z9TDF from a controlled-release dispenser were found to be directly proportional to the airflow rates. Release rate measurements on the Z9TDF dispensers were made for the purpose of estimating the method's precision. The method was shown to give internally consistent results by measurements on another Z9TDF formulation. The accuracy of the method is discussed.Mention of a commercial or proprietary product in this paper does not constitute an endorsement by the USDA.  相似文献   
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Map information for drivers is usually presented in an allocentric-topographic form (as with printed maps) or in an egocentric-schematic form (as with road signs). The advent of new variable message boards on UK motorways raises the possibility of presenting road maps to reflect congestion ahead. Should these maps be allocentric-topographic or egocentric-schematic? This was assessed in an eye tracking study, with participants viewing maps of a motorway network in order to identify whether any congestion was relevant to their intended route. The schematic-egocentric maps were responded to most accurately with shorter fixation durations suggesting easier processing. In particular, the driver's entrance and intended exit from the map were attended to more in the allocentric maps. Individual differences in mental rotation ability also seem to contribute to poor performance on allocentric maps. The results favour schematic-egocentric maps for roadside congestion information, but also provide theoretical insights into map-rotation and individual differences. Statement of Relevance: This study informs designers and policy makers about optimum representations of traffic congestion on roadside variable message signs and, furthermore, demonstrates that individual differences contribute to problems with processing certain sign types. Schematic-egocentric representations of a motorway network produced the best results, as noted in behavioural and eye movement measures.  相似文献   
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OH Pepsios     
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Information Exchange in Virtual Communities: A Comparative Study   总被引:1,自引:0,他引:1  
As more and more consumers spend more money on the Internet, traditional retailers and manufacturers as well as entrepreneurial dot-coms are jousting to explore and shape this new business opportunity. Their long-term survival and profitability may be determined by how well the Web site helps form and sustain positive attitudes toward the site and, eventually, toward the product or the company. The purpose of this study is two-fold: (1) to examine if and how attitude toward the Web site (Ast) affects consumer brand choice; and (2) to examine the association between Ast and consumers' confidence in choice, and the moderating effect of consumer product knowledge in its relationship. The study asked participants to choose a laptop brand after visiting three laptop manufacturer Web sites for a total of 30 minutes. Their product knowledge and attitude toward the three Web sites were also measured. The study found that attitude toward the Web site is a good predictor of consumer brand choice. In addition, confidence in choice seemed to be affected by Ast, depending on product knowledge. For a group with low product knowledge (novices), Ast was likely to influence confidence in choice. For a group with high product knowledge (experts), however, Ast did not seem to affect confidence in choice.  相似文献   
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