Aim To observe the effects of promethazine on the analgesia,hypnosis,amnesia and therapeutic index of isoflurane.Methods The experiments were designed to study promethazine on the analgesic effect of isoflurane by hot-plate test and writhing test,and to study the effect of promethazine on the sleeping time of isoflurane by the method of righting reflex,and the amnesia of isoflurane by Morris water maze,and the ED_(50),LD_(50) by sequential method in mice.Results The result of hot-plate test and writhing test indicated that promethazine could enhance the analgesic effect of isoflurane(P＜0.05 or P＜0.01);through the experiment of righting reflex, sleeping time of isoflurane in mice was extended by promethazine(P＜0.01);in Morris water maze experiment, the average latency in the combination of promethazine and isoflurane was longer than that of the promethazine group or isoflurane group(P＜0.05 or P＜0.01), while aiming to the residence time, the combination of the two was shorter than that in the third quadrant(P＜0.01 or P＜0.05),the TCPP of the group of isoflurance was more than that of the combination group;promethazine could decrease the ED_(50) of isoflurance(P＜0.01),but it did not obviously affect its LD_(50)(P＞0.05).Conclusion Promethazine can not only reinforce the effect of isoflurance on analgesia,hypnosis and amnesia, but also boost the therapeutic index of isoflurance.

Objective To explore the effect of scanning time on CT perfusion (CTP) imaging quality and the accuracy of parameters in acute stroke patients.Methods CTP data of 30 patients with unilateral acute cerebral infarction were investigated retrospectively.CTP data with scanning times of 56 s,52 s,48 s,44 s,40 s and 36 s were analyzed for image postprocessing,the time density curves (TDCs) of the superior sagittal sinus (SSS),perfusion maps and the parameter values of ROI were obtained,and the first passage time of SSS was recorded.Results Compared with 56 s group,there was no significant difference of the image quality in the scanning time of 52 s group and 48 s group (both P＞0.05).The image quality was significantly negatively correlated with the first passage time of SSS in 52 s group,48 s group,44 s group,40 s group and 36 s group.Compared with 56 s group,there were significant differences in partial parameters of ROI when the scanning time was 44 s (all P＜0.05).Conclusion Decreasing whole-brain CTP scanning time reasonably can ensure the image quality and the accuracy of parameters and reduce the radiation dose.The whole-brain CTP with delay of 8 s,and scanning time of 48 s are recommended.