首页> 美国政府科技报告 >Influence of Exposure Patterns of Nitrogen Dioxide and Modifications by Ozone on Susceptibility to Bacterial Infectious Disease in Mice
【24h】

Influence of Exposure Patterns of Nitrogen Dioxide and Modifications by Ozone on Susceptibility to Bacterial Infectious Disease in Mice

机译:二氧化氮暴露模式和臭氧改性对小鼠细菌感染性疾病易感性的影响

获取原文

摘要

The nitrogen dioxide (NO2) diurnal cycle found in urban communities usually consists of a low basal concentration upon which are superimposed higher concentration peaks or spikes of short duration. Various components of the environmental exposure mode were examined to assess effects of urban exposure profiles on susceptibility to infectious pulmonary disease. Mice were exposed to NO2 peaks of 4.5 ppm for 1, 3.5, or 7 h, challenged with Streptococcus sp. either immediately or 18 h postexposure, and then observed for mortality. When the streptococcal challenges were immediately after NO2 exposure, the mortality rate was directly related to the length of peak exposure, whether or not a basal exposure was used, and all peak lengths significantly increased mortality. When the challenge was delayed for 18 h after the peak exposure, spiked exposure, of 3.5 and 7 h increased mortality to the same degree. If a 1-h peak exposure to 4.5 ppm was superimposed twice daily upon a continuous basal NO2 concentration of 1.5 ppm, there was a suggestive trend toward increased mortality near the end of the second week of exposure when challenge occurred immediately after the morning spike.

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号