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The LP-BM5 murine leukemia virus causes acquired immunodeficiency syndrome in C57BL/6J mice (MAIDS), similar to that of AIDS in humans. The objective of this study was to determine the effect of LP-BM5 viral infection on cellular activation and membrane integrity of splenocytes. Oxidative burst in splenocytes in response to exposure to PMA (20 microg/ml) was significantly higher (p<.02) in infected than in control mice at two weeks post-infection using luminol-enhanced chemiluminescence. By 13 weeks post-infection superoxide anion production in infected mice was significantly lower when compared to controls coinciding with decreased proliferative response to mitogens. The extent of cell membrane damage as indicated by lactic dehydrogenase (LDH) activity in serum was significantly higher in infected than in control mice (p<.001). The results from this study suggests that LP-BM5 virus causes an initial stimulation of cellular activity followed by a decreased cell activation characterized by decreased proliferation of splenocytes and decreased oxygen radical production. Decreased cell membrane integrity indicated by increased LDH activity may partly be responsible for these changes.  相似文献   
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A focus on the importance of leisure in the development of student nurses has been neglected in the 1990s. This study considers 444 prospective nurses on conventional, diploma and degree courses in two areas of England. It examines their activities associated with socializing, their social support networks and their use of clubs, sports and hobbies before entering nursing. It is evident that students enter nurse training with a wide variety of leisure experiences. Changing recruitment patterns and the structure of nurse training has an effect on the leisure needs of prospective nurses which must be addressed.  相似文献   
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The data presented here are part of an on-going longitudinal study of the relationship between socioeconomic status and mortality in the major metropolitan centers of Ohio. Using a Standardized Mortality Ratio, we find that mortality in the seven-city urban aggregate exceeds that of the rest of the state by 39 per cent for the nonwhite population and only 1 per cent for the white population. Further, for the nonwhite population, living in a high income area has no discernible health benefit for nonwhites as compared to whites. On the other hand, for the AIDS virus, there is a clear inverse association between economic status and mortality from AIDS. It is clear that the interrelationship among race, economic status, and health continues to be a complex one on which further research is needed.  相似文献   
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A 68-year-old Caucasian woman presented to the hospital with nodular pulmonary infiltrates and acute renal failure. Wegener's granulomatosis was initially considered to be most likely because of the presence of increased serum levels of c-anti-neutrophil cytoplasmic antibodies (c-ANCA). A consultation through the Internet after a renal biopsy demonstrated crescentic, necrotizing glomerulonephritis and linear deposits of immunoglobulin G (IgG) and complement C3, typical of anti-glomerular basement membrane (GBM) disease. Hemodialysis was instituted; however, the patient suddenly developed a massive cerebral hemorrhage and died before full therapy could take effect. Postmortem analysis of the patient's sera revealed high titers of IgG against the alpha 3 NC1 domain of type IV collagen. Serologic evidence of both p-ANCA and anti-GBM antibodies are becoming more frequently recognized in the setting of rapidly progressive glomerulonephritis. The patient reported here had the unusual combination of c-ANCA antibodies with anti-GBM disease, and this association raises complex questions regarding the pathogenesis of this type of renal injury.  相似文献   
16.
Intracellular tyrosine kinases link the G protein-coupled m1 muscarinic acetylcholine receptor (mAChR) to multiple cellular responses. However, the mechanisms by which m1 mAChRs stimulate tyrosine kinase activity and the identity of the kinases within particular signaling pathways remain largely unknown. We show that the epidermal growth factor receptor (EGFR), a single transmembrane receptor tyrosine kinase, becomes catalytically active and dimerized through an m1 mAChR-regulated pathway that requires protein kinase C, but is independent of EGF. Finally, we demonstrate that transactivation of the EGFR plays a major role in a pathway linking m1 mAChRs to modulation of the Kv1.2 potassium channel. These results demonstrate a ligand-independent mechanism of EGFR transactivation by m1 mAChRs and reveal a novel role for these growth factor receptors in the regulation of ion channels by G protein-coupled receptors.  相似文献   
17.
Two patients are presented where internal mammary artery grafting was performed for the relief of symptomatic coronary artery disease. At follow-up the internal mammary artery was occluded and a communication between the internal mammary vein and the native coronary artery was demonstrated. These patients were characterised by the early recurrence of angina or the appearance of a continuous murmur. Both patients were treated by re-operation with ligation of the arterio-venous fistula and saphenous vein grafting.  相似文献   
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A mathematical model of mass transfer through a heterogeneous, multiphase barrier has been developed where the dispersed phase is capable of uptake of the diffusant according to a linear relationship. The model was used to describe the penetration of drugs through dispersions of permeable globules in media of known diffusional properties. Water-in-oil-in-water (W/O/W) multiple emulsions have been studied by this method. When used to analyze data obtained with a simple diffusion cell, the model allows the calculation of the mass transfer coefficient which characterizes the diffusional mass transfer across oil-water interfaces within the emulsions. The mass transfer coefficient is directly related to the drug release rate from the internal phases of multiple emulsions. Those cases where instantaneous equilibria are established or where impermeable globules are present can be treated as special limiting cases. Differential equations which express diffusant concentrations as functions of time, space, and dispersion system parameters have been solved by Laplace transformation without recourse to numerical methods. The values of the mass transfer coefficient are shown to reflect the physical characteristics of multiple emulsion systems.  相似文献   
20.
Strong fiber Bragg gratings were written through the standard polymer coatings of "off-the-shelf" high numerical aperture single-mode optical fibers after a few seconds exposure with femtosecond pulse durations of infrared radiation through a phase mask. While writing through the acrylate coating, we obtained index modulations of up to 1.4 x 10-3 and 7 x 10-4 with and without H2 -loading, respectively.  相似文献   
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