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51.
DNA-based vaccines: new possibilities for disease prevention and treatment. 总被引:1,自引:0,他引:1 下载免费PDF全文
A Robinson 《Canadian Medical Association journal》1995,152(10):1629-1632
Ottawa researcher Dr. Heather L. Davis has become a pioneer in the development of DNA-based vaccines. With her collaborators in France and Germany Davis found that introducing the DNA code for the envelope protein of the hepatitis B virus into the muscle tissue of mice prompted a strong and sustained immune response. She believes that DNA-based vaccines could prove to offer many advantages over conventional vaccines, not least of which are greater safety and effectiveness and reduced cost. She has also begun to explore the potential of DNA-based vaccines for use in the treatment of disease. In recent experiments Davis and colleagues in France have successfully used DNA vaccination to cure transgenic mice of a chronic hepatitis B carrier state. 相似文献
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Selective inhibition of T cell proliferation but not expression of effector function by human alveolar macrophages 总被引:1,自引:0,他引:1 下载免费PDF全文
BACKGROUND: Alveolar macrophages are thought to play an important part in regulating lung immune responses. While it is clear that human alveolar macrophages suppress T cell proliferation in vitro, the mechanisms by which this is achieved are not clear, nor is it known whether alveolar macrophages also inhibit other aspects of T cell function. METHODS: Peripheral blood mononuclear cells were stimulated with phytohaemagglutinin or house dust mite allergen, and cultured with variable numbers of autologous alveolar macrophages obtained by bronchoalveolar lavage from 20 normal subjects. RESULTS: Alveolar macrophages induced a reversible inhibition of T cell proliferation in response to both mitogen and allergen stimulation, with the latter being considerably more susceptible to inhibition. This was achieved via heterogenous mechanisms, involving both soluble factors derived from alveolar macrophages and cell-cell contact. Despite inhibiting proliferation, alveolar macrophages had little or no effect on T cell calcium flux, the characteristic changes in CD3, CD2, CD28 and interleukin-2 (IL-2) receptor expression which accompany normal T cell activation, and IL-2 and interferon gamma secretion. In contrast, alveolar macrophages inhibited the tyrosine phosphorylation of proteins which may be involved in IL-2 receptor-associated signal transduction. CONCLUSIONS: The immunoregulatory properties of alveolar macrophages are relatively selective, allowing T cell activation and cytokine secretion while inhibiting T cell proliferation within the lung.
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T. F. Chen E. Robinson S. R. Payne E. Robinson 《Annals of the Royal College of Surgeons of England》1994,76(3):190-193
A catheter audit was performed at the Central Manchester Trust, which found that there was excessive ordering, inappropriate catheter selection by size, materials, balloon size and poor guidelines on catheter storage. From these findings and from the available literature, we have proposed guidelines on catheter selection with the aim of offering the best patient care and to provide cost efficiency which may be of benefit to other hospitals. 相似文献
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Development and evaluation of a presurgical preparation program 总被引:2,自引:1,他引:1
Three presurgical preparation programs were developed and evaluated in an Australian hospital utilizing an additive component design. The component basic to all three preparation programs was modeling. This technique was compared with the additional components of teaching child coping skills and parent coping skills via videotape. Subjects were 28 children between the ages of 4 and 13 years who were scheduled for elective surgery. Anxiety of both the children and parents was assessed by self-report and behavior observation. Results indicated that there was no further anxiety reduction by the addition of child and parent coping skills. Results are discussed in terms of the viability of teaching coping skills via videotape particularly to parents. Methodological difficulties associated with research in this area are examined. 相似文献