Objective To study the effective composition of Aster ageratoides Turcz for relieving asthma and its toxicity . Methods Seventy‐two qualified male guinea pigs ,body mass(300 ± 20)g ,were randomly divided into the control group ,aminophyl‐line group(0 .047 g/kg) and different ratio group of total saponins and total flavonoids (8∶1 ,4∶1 ,2∶1 ,1∶1 ,1∶2 ,1∶4 ,1∶8) . Every group received at dose of 0 .38 g/kg once a day for 3 days by intragastric administration .The effect of relieving asthma was taken as the indicators for the optimization of compositions ,which was detected by observing the latent period of asthma induced by acetylcholine‐histamine in guinea rats .The relaxation percentage of smooth muscle retracted by acetylcholine was detected by Pow‐erlab biological signal collecting system when aminophylline(1 .25 mg/mL) and different matching drugs(0 .02 g/mL) were added in Krebs′solution .The acute toxicities of total saponins ,total flavonoids and mixture of total saponins with total flavonoids (ratio of 1∶2) were detected by classical acute toxicity test of mice .Results Compared with the control group ,aminophylline group ,each group latent period of inducing asthma significantly or very significantly prolonged (P<0 .05) ,among them ,1∶1 ,1∶2 ,1∶4 group and other matching group were significantly different(P<0 .05) ,but 1∶2 group cited the longest incubation period .Aminophylline group and the ratio could significantly relaxe guinea pig tracheal smooth muscle retracted by acetylcholine .Aminophylline group di‐astolic percentage was the largest(24 .12 ± 1 .20)% ,all the groups were less than the percentage of diastolic aminophylline group (P<0 .05) ,but in 1∶2 group with the closest .Aster ageratoides Turcz ,tatarian aster total saponins ,total flavonoids and the ratio of 1∶2 to mice maximum tolerance was respectively 300 ,345 ,325 g/kg .Conclusion For the same total dosage ,the relieving asth‐ma effects of proportions of 1∶2 Aster ageratoides Turcz were obvious .There are no abnormal changes in the acute toxicity trila with total flavonoids ,total saponins ,as well as the ratio of 1∶2 ,safety is relatively good .

Objective: To analyze the quadrivalent influenza vaccine intention of 718 health care workers (HCWs) in the Pearl River Delta region from 2015 to 2017. Method: In May 2018, 718 HCWs from the department related to the diagnosis and treatment of influenza in 17 hospitals (6 tertiary hospitals, 5 secondary hospitals and 6 primary hospitals) from Guangzhou, Jiangmen, Zhuhai and Dongguan were selected by using stratified sampling method. Questionnaire survey and face-to-face interview were used to collect the information of influenza vaccination, the intention of the quadrivalent influenza vaccine, the acceptance of free and required vaccination policies, and recommendations for increasing influenza vaccination intentions from 2015 to 2017. The multivariate logistic regression was used to analyze factors associated with the vaccination intention. Results: A total of 718 HCWs were surveyed and 147 of them were interviewed face to face. Among them, the vaccination rate of primary hospitals [17.39%(40/230)] was higher than that of other hospitals (χ²=15.80, P<0.05). If the vaccine could be free, 84.82% (609/718) of HCWs would like to be vaccinated. The multivariate logistic regression showed that the factors, HCWs who were aged ≥50 years (OR=3.44, 95%CI:1.43-8.28), worked in department of prevention and health care (OR=2.35, 95%CI:1.16-4.75), learned about the quadrivalent influenza vaccine (OR=2.94, 95%CI:2.08-4.18), knowed that HCWs are priority (OR=2.33, 95%CI:1.56-3.48), and had a history of trivalent influenza vaccination from 2015 to 2017 (OR=4.70, 95%CI:3.08-7.15), were associated with the vaccination intention. Conclusion HCWs in the Pearl River Delta region had weak inclination of getting quadrivalent influenza vaccine. HCWs who were age (≥50 years old), worked in department of prevention and health care, learned about the quadrivalent influenza vaccine, knowed that HCWs are priority, and had a history of trivalent influenza vaccination from 2015 to 2017 were factors positively associated with the vaccination intention.