Objective To investigate the value of "one-stop" scanning of coronary and head and neck CTA in patients with normal body mass index (18 kg/m2 ≤ BMI ≤ 25 kg/m2) using low tube voltage (80 kVp).Methods In a retrospective analysis 80 patients with normal body mass index who had completed "one-stop" scanning of coronary and head and neck CTA were divided into A and B groups according to different scanning method,and 40 consecutive cases were selected in each group.Scanning parameters of group A and group B were tube voltage 80 kV,coronary CTA tube current 550 mA,head and neck CTA tube current 500 mA,and tube voltage 100 kV,coronary CTA tube current 450 mA,head and neck CTA tube current 400 mA separately.Subjective evaluation and objective evaluation were performed on the image quality of the two groups.CT values of coronary artery and head and neck CTA trunk branch vessel,contrast-to-noise ratio (CNR),image noise (SD) and effective dose between the two groups were compared.Results The image quality of both groups met the diagnostic requirements,and there was no statistically significant difference in subjective scores between two groups (P＞0.05).The CT values of coronary arteries,the main branches of the head and neck (the common carotid artery,the internal carotid artery) and SD of head and neck CTA were significantly different between two groups (t=4.737,6.552,3.359,2.165,2.685,4.617,P＜0.05).There was no statistically significant difference in SD of coronary CTA,CT values and CNR between head and neck vessels (middle cerebral artery) in group A and group B (P＞0.05).The effective dose of coronary CTA in group A (1.16±0.20) mSy was reduced by 51.1％ than that in group B (2.37±0.77) mSv.The effective dose of head and neck CTA in group A (0.37±0.03) mSv was reduced by 47.9％ than that in group B (0.71 ± 0.17) mSv.Conclusions The image quality with subjective evaluation met the diagnostic requirements when using a low-tube voltage for "one-stop"scanning of coronary and head and neck CTA.The CNR values were basically consistent with the conventional scanning method,and the patient effective dose was reduced by about 50％.

Objective:To investigate the role of dopamine receptors in the central amygdala (CeA) in reduction of the anxiety level by propofol in a mouse model of post-traumatic stress disorder (PTSD).Methods:Fifty-six SPF healthy adult male C57BL/6 mice, aged 10 weeks, weighing 20-25 g, were divided into 7 groups ( n=8 each) using a random number table method: control group (C group), PTSD group (P group), PTSD+ propofol group (PP group), PTSD+ fat emulsion group (PF group), PTSD+ propofol+ normal saline group (PPN group), PTSD+ propofol+ dopamine receptor D1 (DRD1) antagonist group (PP+ DRD1-Ant group), and PTSD+ propofol+ DRD2 antagonist group (PP+ DRD2-Ant group). The PTSD model was developed by continuous plantar electric shock for 3 days. Propofol 120 mg/kg was intraperitoneally injected after successful establishment of the model in PP group, and the equal volume of fat emulsion was intraperitoneally injected in PF group. In PPN group, PP+ DRD1-Ant group and PP+ DRD2-Ant group, the equal volume of normal saline, DRD1 antagonist hydrochloride and DRD2 antagonist eticlopride hydrochloride were injected in bilateral CeA regions, respectively, 30 min later the efficacy of drugs reached the peak, and then propofol 120 mg/kg was intraperitoneally injected. The anxiety levels were measured at 4 h (T 1) and day 3 after propofol injection (T 2) by the open field test and elevated cross maze test. Results:Compared with C group, the time spent entering the open and central areas was significantly shortened at T 1, 2, and the number of entering the open and central areas was decreased at T 1, 2 in P group ( P<0.001). Compared with P group, the time spent entering the open and central areas was significantly prolonged at T 1, the number of entering the open and central areas was increased at T 1 ( P<0.001), and no significant change was found at T 2 in PP group ( P>0.05), and no significant change was found in the aforementioned parameters at T 1, 2 in PF group ( P>0.05). Compared with PPN group, the time spent entering the open and central areas was significantly shortened at T 1, and the number of entering the open and central areas was decreased at T 1 in PP+ DRD2-Ant group ( P<0.001), and no significant change was found at T 1 in PP+ DRD1-Ant group ( P>0.05). Conclusions:Activation of DRD2 in the CeA is involved in the process by which propofol reduces the anxiety level of mice with PTSD.