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411.
A serum glycoprotein, Gc protein (vitamin D3-binding protein), can be converted by beta-galactosidase of B cells and sialidase of T cells to a potent macrophage-activating factor (MAF), a protein with N-acetylgalactosamine as the remaining sugar moiety. Thus, Gc protein is the precursor for MAF. Treatment of Gc protein with immobilized beta-galactosidase and sialidase generates a remarkably high titered macrophage-activating factor (GcMAF). When peripheral blood monocytes/ macrophages (designated macrophages) of 33 systemic lupus erythematosus patients were incubated with GcMAF (100 pg/ml), the macrophages of all patients were activated as determined by superoxide generation. However, the precursor activity of patient plasma Gc protein was lost or reduced in these patients. Loss of the precursor activity was the result of deglycosylation of plasma Gc protein by alpha-N-acetylgalactosaminidase activity found in the patient plasma. Levels of plasma alpha-N-acetylgalactosaminidase activity in individual patients had an inverse correlation with the MAF precursor activity of their plasma Gc protein. Deglycosylated Gc protein cannot be converted to macro-phage-activating factor. The resulting defect in macro-phage activation may lead to an inability to clear pathogenic immune complexes. Thus, elevated plasma alpha-N-acetylgalactosaminidase activity resulting in the loss of MAF precursor activity and reduced macro-phage activity may play a role in the pathogenesis of systemic lupus erythematosus.  相似文献   
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A novel natural product (1), with antifungal activity was isolated from the culture broth of an actinomadurae. The active compound was separated from broth by n-butanol extraction and purified by silica gel and multicoil counter current chromatography. Physico-chemical data suggested the structure of this compound to be a novel macrolactam disaccharide related to Sch 38518 (3). The structure was determined by spectroscopic studies on the acetate derivative. It was active against Candida spp. (MIC's, 4 approximately 64 micrograms/ml) but less than the monosaccharide, Sch 38518 (MIC's, 1 approximately 16 micrograms/ml).  相似文献   
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Officials from the National Council of State Boards of Nursing report how developments in key areas will affect nursing practice.  相似文献   
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This study was designed to compare the course of change of two groups of conduct-disordered adolescents in two theoretically distinct residential treatment programs: a Therapeutic Community and a modified Token Economy. In all, 28 clients were assessed on multiple measures at three points in the treatment process in a repeated measures design. Results of the study indicated that, despite an overall trend toward improvement in both groups, there was little significant difference between the rates of progress over time. Dropouts and nondropouts could be differentiated only by a small number of baseline scores and the amount of family contact during placement. While comparative studies in residential treatment have been lacking, it appears that a more promising approach would be to examine common features of different models. The results of this study support the need for qualitative research focusing on the interaction of client attributes and underlying components of treatment modalities.  相似文献   
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Recovery of spatial resolving capacity (acuity) of central vision after temporary blindness induced by prolonged (1.5, 3, 6 min) light adaptation to a sun or incandescence lamp (20, 40, 80 thous. lux) illuminated white screen was studied. The recovery time increased exponentially with an increase in energy light stimulation (product of brightness of the deadapting source by the time of action). A general formula describing the relationship between the time of recovery of acuity and brightness of the test table and energy of light stimulus was derived.  相似文献   
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