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Crry (complement receptor 1–related protein/gene y) is a key cellular complement regulator in rodents. It is also present in Fx1A, the renal tubular preparation used to immunize rats to induce active Heymann nephritis (HN), a model of membranous nephropathy. We hypothesized that rats immunized with anti-Fx1A develop autoantibodies (auto-Abs) to Crry as well as to the megalin-containing HN antigenic complex, and that anti-Crry Abs promote the development of injury in HN by neutralizing the complement regulatory activity of Crry. Rats immunized with Fx1A lacking Crry remained free of proteinuria and glomerular deposits of C3 during a 10-wk follow-up despite typical granular immunoglobulin (Ig)G deposits in glomeruli. Anti-Fx1A auto-Abs were present in their sera at levels that were not different from sera pooled from proteinuric rats with HN induced with nephritogenic Fx1A. Passive administration of sheep anti-Crry Abs to rats immunized with Crry-deficient Fx1A led to proteinuria and glomerular C3 deposition, which were not seen in such rats injected with preimmune IgG, nor in rats with collagen-induced arthritis injected with anti-Crry IgG. To directly examine the role of Crry in HN, rats were immunized with Crry-deficient Fx1A reconstituted with rCrry. This led to typical HN, with 8 out of 15 rats developing proteinuria within 14 wk. Moreover, the extent of glomerular C3 deposition correlated with proteinuria, and anti-Crry Abs were present in glomerular eluates. Thus, Crry is a key nephritogenic immunogen in Fx1A. Formation of neutralizing auto-Abs to Crry impairs its function, leading to unrestricted complement activation by Abs reactive with the HN antigenic complex on the epithelial cell surface.  相似文献   
37.
Hexane and methanol extracts of heartwood, bark/sapwood and leaves of twelve taxa of Juniperus from the United States were assayed for antifungal and antibacterial activities. The hexane extract of the heartwood of several junipers appeared comparable in antibacterial activity to streptomycin. Antibacterial activity of the hexane extracts from the bark/sapwood of J. monosperma and J. californica were comparable to streptomycin. No appreciable antibacterial activities were found in the leaf extracts from any species examined. No antifungal activities comparable to amphotericin B were found in either hexane or methanol extracts of the heartwood nor from the bark/sapwood. Antifungal activity against Cryptococcus neoformans comparable to amphotericin B was found in the hexane extract of the leaves of J. occidentalis var. australis. The methanol extracts from the leaves of J. osteosperma and J. californica had antifungal activities comparable to amphotericin B against Trichophyton mentagrophytes.  相似文献   
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A simple enzyme immunoassay has been developed based on measuring antibodies to synthetic peptides corresponding to sequences in the Epstein-Barr nuclear antigen (EBNA). This assay, which is reproducible, quantitative, and simple to perform and interpret, can be an effective tool to aid in the diagnosis of infectious mononucleosis and nasopharyngeal carcinoma.  相似文献   
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A 528-bed community teaching hospital redesigned its patient care delivery system, implementing a collaborative practice model on the 30-bed inpatient rehabilitation unit in April 1990. This model is a patient-centered delivery model that encourages the healthcare team to facilitate the achievement of patient outcomes within effective time frames and with an appropriate use of resources. The collaborative practice model includes a nurse case manager's role for the staff nurse, which had as its framework the concept of nursing case management. Tested project management techniques were used to ensure a successful implementation process. Various strategies, such as using project teams and providing educational programs, were used to respond to the issues of role conflict and overlap, especially between social workers and nurse case managers. The implementation of this model provided a number of benefits, including improved interdisciplinary relationships and decreased length of stay.  相似文献   
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A sensitive and accurate flow cytometry (FCM) based method has been developed to detect and quantitate a novel marine fish iridovirus (Singapore grouper iridovirus, SGIV) after amplification in cell cultures. Confluent grouper cell (GP) monolayers were infected with SGIV. When advanced cytopathic effect (CPE) appeared, the cell cultures were fixed and permeabilized, and then reacted with monoclonal antibodies specific against SGIV, followed by a second antibody conjugated with FITC (anti-mouse IgG-FITC). A Coulter EPICS Elite ESP flow cytometer was used to directly detect and analyze the percentage of virus-infected cells. Three fixation and permeabilization methods were evaluated. The kinetics of the virus infection process was determined. The FCM procedure enables large amounts of cells to be screened rapidly for infectivity, and it can also detect low levels of virus infection. As early as 8 h after inoculation with the virus, 0.34% of infected cells were detected in cell culture. The maximum level of infection was obtained at 72 h. The efficiency and reliability of the FCM procedure were compared with those of the standard methods of immunofluorescence microscopy and PCR.  相似文献   
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