Objective To observe image quality and impact factors for single heart beat coronary CTA (CCTA) with prospectively ECG-triggered CT in patients with low,high heart rate (HR) and arrhythmia.Methods Single heart-beat CCTA was performed for 208 patients with prospectively ECG-triggered 256-slice wide-detector CT without drug control of HR.The patients were divided into 3 groups,including low HR group (n=87,HR≤70 bpm),high HR group (n=38,HR＞70 bpm) and arrhythmia group (n=83,HR variation ＞ 10 bpm in 5 cardiac cycles).The normal reconstruction phase was set as 75％ or 45％ in R-R interval,while the optimal phase was that with the least motion artifacts.Univariate linear regression was used to analyze the impact factors for image quality.Results Compared with images of normal phase,the optimal phase of 105 patients (105/208,50.48％) was altered.In the optimal images,imaging quality,SNR and CNR were not significantly different among 3 groups (all P＞0.05).Image quality was significantly influenced by reconstruction phase and artifact type (both P＜0.001).Conclusion During prospectively ECG-triggered 256-slice wide-detector CCTA without drug control of HR,high HR and arrhythmia are not significant impact factors of image quality.

0.05). But according to the data, IL-8 in Qingqinye low dosage group was lower than model group, positive medicine group, Qingqinye high dosage group and Qingqinye middle dosage group. TNF-? in Qingqinye group was lower than model group and positive medicine group, especially in Qingqinye middle dosage group. Pathological section with articular cavity and surrounding tissues were better in positive medicine group and Qingqinye group. Conclusion Qingqinye has a certain effect for repairing joint immune pathological injury in hyperuricemia model rats.

Objective To investigate the effects of modafinil,a new wake-promoting agent,on simulated flight performance during 48 h sleep deprivation(SD).Method Six male healthy young volunteers were exposed to two periods of 48 h continuous wakefulness during the crossover experiment.In one period,three 200 mg doses of modafinil were given and in the other,separated by two weeks,matching placebos were administered.The SD time started from 8:00 of the first day to 8:00 of the third day.Drug was given at 0:00,16:00 of the second day and 0:00 of the third day.Flight performance in J7-E flight simulator was tested at 21:00 of the first day and 1,3,5,7 h after each drug administration.Result The scores of simulated flight performance in the placebo group decreased with time during SD and became significant at 1:00～7:00 of the third day.Numbers of errors increased with time during SD,especially in the left ascending turn stage and the descending & landing stages.Compared with the placebo,flight performance was significantly increased after the third administration of modafinil.Numbers of errors during 48 h SD and at 1:00～7:00 of the third day in modafinil group was 19% and 40% lower than those in placebo group respectively.Conclusion Simulated flight performance during 48 h SD is significantly improved after repeated administration of modafinil,especially when the impacts of SD and the circadian trough are combined.

Objective　To observe the effect of short-term repeated administration of several psychoactive drugs on locomotor activity and cerebral monamine transmitters in mice and evaluate tolerance of drug action and their side-effects.　Methods　Male mice were used as subjects. The experiment of central stimulants was divided into 3 groups (n=6 each): ①control;②caffeine(Caf) 30 mg/kg; ③dexamphetamine(Dex) 10 mg/kg. The experiment of hypnotics included 4 groups: ①control; ②triazolam (TZ) 0.04 mg/kg;③seconal (Sec) 60 mg/kg; ④melatonin (Mel) 120 mg/kg. These drugs were given orally to the mice once daily for 7 days. Body weight and locomotor activity were determined on first day and 7th day. After repeated administration of Dex and TZ for 7 days, monamine transmitters and their metabolites in mouse brain were determined by reverse phase HPLC with electrochemical detector.　Results　①There was no significantly difference of body weight between the control and drug-treated groups. ②Stimulating action of Caf and Dex was significantly increased on 7th day (P<0.05, compared with first day). ③Although the significant sedative effect of hypnotics remained after repeated administration of hypnotics for 7 days, their potency was reduced(P<0.05, compared with first day). ④ No significant changes of monamine transmitters were found in cerebral cortices of mice after repeated administration of Dex and TZ for 7 days; but DOPAC and 5-HIAA in Dex group and 5-HIAA in TZ group was significantly decreased (P<0.05, compared with the control).　Conclusion　①The sedative effect of several hypnotics was decreased after repeated medication; ②Dex and TZ might have detrimental effects on some monamine transmitter metabolites in mouse brain after continuous administration for one week.

Objective　To observe the effect of short-term repeated administration of several psychoactive drugs on locomotor activity and cerebral monamine transmitters in mice and evaluate tolerance of drug action and their side-effects.　Methods　Male mice were used as subjects. The experiment of central stimulants was divided into 3 groups (n=6 each): ①control;②caffeine(Caf) 30 mg/kg; ③dexamphetamine(Dex) 10 mg/kg. The experiment of hypnotics included 4 groups: ①control; ②triazolam (TZ) 0.04 mg/kg;③seconal (Sec) 60 mg/kg; ④melatonin (Mel) 120 mg/kg. These drugs were given orally to the mice once daily for 7 days. Body weight and locomotor activity were determined on first day and 7th day. After repeated administration of Dex and TZ for 7 days, monamine transmitters and their metabolites in mouse brain were determined by reverse phase HPLC with electrochemical detector.　Results　①There was no significantly difference of body weight between the control and drug-treated groups. ②Stimulating action of Caf and Dex was significantly increased on 7th day (P<0.05, compared with first day). ③Although the significant sedative effect of hypnotics remained after repeated administration of hypnotics for 7 days, their potency was reduced(P<0.05, compared with first day). ④ No significant changes of monamine transmitters were found in cerebral cortices of mice after repeated administration of Dex and TZ for 7 days; but DOPAC and 5-HIAA in Dex group and 5-HIAA in TZ group was significantly decreased (P<0.05, compared with the control).　Conclusion　①The sedative effect of several hypnotics was decreased after repeated medication; ②Dex and TZ might have detrimental effects on some monamine transmitter metabolites in mouse brain after continuous administration for one week.

Objective To observe the effects of tea polyphenols (TP) on cardiac function and myocardial ultrastructure in rats after repeated +10 Gz stress. Method Twenty four male Wistar rats were randomly divided into three groups (n=8 each): group A (control), group B (+10 Gz), group C (+Gz with TP). Group B and C were repeatedly exposed to +10 Gz (each for 30 s, onset rate about 0.5 G/s, 3 times/d with +1 Gz 1 min intervals, 3 d/wk, 4 weeks in total), but group A was only submitted to +1 Gz. TP(200 mg.kg-1) was given orally to group C about 1h prior to the +Gz experiment, and distilled water was given to group A and B.Function of isolated rat working hearts and myocardial ultrastructure were observed. Result A significant decrease of left ventricular systolic pressure (LVSP) and injury of myocardial structure in rats were demonstrated after repeated +10 Gz stress. But TP could remarkably elevate the LVSP and improve myocardial ultrastructural injury in +10Gz stressed rats. Conclusion These results indicated that repeated high G exposure may produce cardiac structural and functional injuries in rats which might be partly related to free radical metabolism; and antioxidant TP had significant protective effects on the hearts of +Gz stressed rats.

Objective To observe the effects of repeated +10 Gz stress on cerebral lipid peroxidation,liver and renal function in rats and the prophylactic effects of antioxidant tea polyphenols(TP).Method Twenty-four male Wistar rats were randomly divided into three groups(n=8 each):group A(control),group B(+10 Gz),and group C(TP).Group B and C were exposed to repeated +10 Gz stress(each for 30s,onset rate about 0.5 G/s,3 times/d with +1 Gz 1 min intervals,3 d/wk,4 weeks in total),but group A was only submitted to +1 Gz.TP(200 mg/kg) was given orally in group C about 1 h prior to the +Gz experiment,while distilled water was given in group A and B.Lipid peroxidation in the brain,liver and renal functions and serum lipids were determined.Results As compared with the control,lipid peroxidation in rat cerebral homogenate,mitochondria and cytoplasm was significantly increased( P<0.05),and serum creatinine concentration was markedly elevated after repeated +10 Gz stress(P<0.01).But,TP had significant inhibitory effect on +10 Gz stress induced peroxidative injury in rat brain and reduced the serum creatinine level.There were no differences of serum triglyceride and total cholesterol concentrations and glutamic-pyruvic transaminase activity among the three groups.Conclusion These results indicated that repeated high +Gz stress could bring about peroxidative injury in brain and harmful effect on renal function,and natural antioxidant TP had signficant protective effects.