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61.
The development of a cell-mediated immune response to Sendai virus infection in mice was examined by the use of a 51Cr release assay of cytotoxicity. A low level of "background cytotoxicity" to Sendai virus-infected L cells was found in the spleens of uninfected CBA mice. Spleen cells from Sendai-infected mice showed an elevated level of cytotoxicity against these target cells for a period of 5 weeks, commencing 4 days after infection of the mice. A more transient response was observed in the spleens of mice infected with a serologically distinct virus, the Kunz strain of influenza. This cross-reacting, cell-mediated immune response was intermediate between that observed in unsensitized and Sendai-sensitized spleen cells. The relevance of these cell-mediated immune responses to respiratory tract virus infections is discussed. 相似文献
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Guevarra MV Gupta L Heath TC Burgess MA 《Asia-Pacific journal of public health / Asia-Pacific Academic Consortium for Public Health》1999,11(1):20-25
A statewide survey was conducted to ascertain GPs' views in New South Wales (NSW), Australia, about the potential usefulness of strategies to increase immunisation rates and to facilitate providing childhood immunisation in their practice. The survey also explored the usefulness of information sources about immunisation. From September 1997-January 1998, a cross-sectional study using a four page self-administered questionnaire was undertaken. Four hundred GPs practising in NSW, Australia were randomly selected and 343 were eligible to participate. Of these, 281 returned a completed questionnaire (82% response rate). Ninety-one percent and 88% of GPs, respectively, agreed that television campaigns or registering children with the national Australian Childhood Immunisation Register (ACIR) were likely to increase immunisation rates. Sixty-two percent of respondents considered that the media created unwarranted parental concern about immunisation. GPs most commonly rated availability of an ACIR list of children overdue for immunisation, better parent educational material and better access to vaccines as strategies which would make immunisation easier. Sixty percent of respondents felt that increased GP payments would be successful in increasing immunisation rates. Only 51% indicated that they had used the "Australian Immunisation Procedures Handbook 6th edition" (a national clinical practice guideline) in the previous month. This study identified GP support for many initiatives aimed at increasing immunisation rates in Australia although GPs were sceptical about the benefits of some programmes. Studies to monitor the impact of GP incentives on immunisation rates in populations and individual practices are underway. These will be useful in determining whether GPs' opinions found in our study correlate with practice in this regard. 相似文献
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A non-experimental design was employed to conduct both a process and impact evaluation of a video conference for injury control specialists and other community members. The video conference was designed to teach participants how to conceptualize, develop, and implement community-based injury and violence prevention programs. The six-hour event was broadcast to 120 sites all across the United States and had a total of 1270 participants. The video conference format included a panel of injury control specialists and a moderator, video and audio clips that were shown throughout the program, on and off screen activities for participants, and an opportunity for participants to ask questions of the panel. Three groups were included in the evaluation sample: participants; site facilitators; and stakeholders; which included the planning committee members, conference speakers, moderator, and audiovisual personnel. Evaluation data were collected by telephone and in-person interviews, focus groups, and surveys completed at all the viewing sites. Results showed that there was high satisfaction among the participants and that the program should be continued as a series of video conferences with a changing content. There was lower satisfaction with the online activities, applicability of material to their work, and the opportunity with to network with others and to participate in discussion. Recommendations made for improving future programs include shortening the video conference program, focusing on specific issues within injury and violence prevention, training the program presenters on the workings of the satellite video conference technology, use of video streaming, and using web-based forms for registration and evaluation. 相似文献
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A semi-continuous compression/perfusion system has been custom made to allow the application of intermittent hydrostatic pressure, at physiological levels, to regenerating tissues over the long term. To test the system, isolated foal chondrocytes were seeded in resorbable polyglycolic acid meshes and cultured in the system for 5 weeks. The cell/polymer constructs were subjected to an intermittent hydrostatic pressure of 500 psi and were fed semi-continuously. Assays of the resulting tissue constructs indicate that the reactor supports cartilage development and that physiological intermittent compression enhances the production of extracellular matrix by the chondrocytes. The concentrations of sulfated glycosaminoglycan were found to be at least twice as high as those in control (unpressurized) samples. A correlation between the sulfated glycosaminoglycan content and the compressive modulus in pressurized, but not control, samples suggests that physiological intermittent pressurization not only enhances the production of extracellular matrix but may also influence matrix organization resulting in a stronger construct. 相似文献
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Heath SE Kenyon SJ Zepeda Sein CA 《Revue scientifique et technique (International Office of Epizootics)》1999,18(1):256-271
Different disasters have similar consequence on the health and welfare of livestock. Numerous geophysical disasters can exacerbate epizootics, resulting in the deaths of many animals and the reduction of production efficiency. These disasters also present a considerable threat of spoilage of processed foods, endangering public health. Furthermore, large-scale disasters involving animals can modify the long-term stability of national economies, the environment and social structures. The authors discuss the vulnerability of the livestock industry to natural disasters and the impact of floods, droughts and transboundary diseases and pests on national economies. Examples are given on how some losses can be avoided, evaluated and compensated. The role of the veterinarian is presented in relation to work conducted by other relief organisations in cases of emergency. In developing countries, mitigation programmes should focus on strengthening global animal health services. Preparedness needs to be community based, with education provided in a timely manner. Effective recovery from disasters should be based on mitigation programmes, including international trade and mutual aid agreements between neighbouring countries to supply appropriate goods and environmentally and culturally appropriate breeds of livestock. Disaster relief for the care of livestock should be recognised as a form of humanitarian assistance, given the benefits to be derived for public health and the socio-economic implications of successful intervention. 相似文献