银杏叶提取物改善反复脑缺血再灌注小鼠血液流变学的作用

目的：研究银杏叶提取物（ＥＧＢ）改善反复脑缺血再灌注小鼠血液流这的作用。方法：采用反复脑缺血再注模型鼠,应用毛细管微量热沉法和毛细管微量法分别检测血纤维蛋白原含量和红细胞压积数值,并将结果输入全自动血液流变仪得出血浆粘度、血液粘度、血细胞聚集系数,血栓形成系数及微循环滞留时间（ＭＳＴ）。结果：ＥＢＧ２５￣１００ｍｇ／ｋｇ均可不同程度地降低Ｆｉｂ、ＨＣＴ、降低ηｂ、ηｐ、ηｈ,缩小ＶＡＬ及ＴＷＥＬ,     

Comparison of breath-guards and face-masks on droplet spread in eye clinics

IntroductionCOVID-19 has impacted ophthalmic care delivery, with many units closed and several ophthalmologists catching COVID-19. Understanding droplet spread in clinical and training settings is paramount in maintaining productivity, while keeping patients and practitioners safe.ObjectivesWe aimed to assess the effectiveness of a breath-guard and a face mask in reducing droplet spread within an eye clinic.MethodsWe performed a randomised trial of droplet spread using a fluorescein-based cough model to assess the efficacy of a ‘breath-guard’ and ‘face-mask’ to prevent the spread of droplets. The ‘cough’ spray was collected on calibrated paper targets. The sheets were photographed under blue light, with an orange filter on the camera; the position and size of the spots was measured with software originally developed for astronomy.We performed 44 randomised coughs; 22 controls with no breath-guard or face-mask, 11 using breath-guard only and 11 with combined breath-guard and face-mask. We compared both the number of droplets detected and the area of drops on paper targets.ResultsThe average number of droplets in the controls was 19,430 (SE 2691), the breath-guard group 80 (SE 19) droplets (P < 0.001); in the combined In the group the count was 5 (SE 2), a significant drop from shield only (P = 0.008). The mean areas of each target covered by spots for each group were 5.7 ± 0.857% (95% CI), 0.004 ± 0.000104% (95% CI) and 0.001 ± 0.0000627% (95% CI) respectively.ConclusionThese results show that the breath-guard alone reduced the droplet count by 99.93%. Combining the breath-guard with a face-mask reduced the droplet count by over 99.98%. Breath-guards are widely used in clinics and this trial demonstrates that breath-guards with face-masks effectively block droplet spray.Subject terms: Risk factors, Microbiology