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Objective:To investigate the feasibility of reducing radiation dose in coronary CT angiography for patients with arrhythmia with absolute phase and narrow window in prospective electrocardiogram-gating.Methods:200 patients with arrhythmia underwent coronary CT angiography procedure with prospective electrocardiogram-gating adaptive sequence in dual source CT were randomly divided into 2 groups according to the scan mode. Group A was scanned with absolute phase and narrow window(250-450 ms) and group B uesd relative phase and wide window (30%-75%). The other parameters and injection protocol of contrast media were the same in 2 groups. Both image quality and radiation dose of the 2 groups were analyzed.Results:No significant difference of image quality was found between the 2 groups. CTDI vol, DLP, E of group A were all lower than those in group B [CTDI vol : (16.71±8.35) vs.(29.35±17.90)mGy , DLP: (231.04±114.86) vs.(398.27±238.40)mGy·cm , E: (3.23±1.60) vs.(5.57±3.33)mSv, t=-6.40, -6.32、-6.32, P<0.05] . The patients with repeat scan cycles in group A and group B were 81 vs. 22 for 0 cycle , 17 vs. 62 for 1 cycle, 2 vs. 10 for 2 cycles, 0 vs. 6 for 3 cycles( χ2=70.76, P<0.05). Conclusions:The prospective electrocardiogram-gating adaptive CCTA sequence with absolute phase and narrow window can reduce radiation dose while the image quality meets the requirementsfor patients with arrhythmia.
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Purpose To investigate the feasibility of 30 ml low-dose contrast medium in reducing the accumulation of contrast medium in venous system while maintaining enough artery enhancement in 256-slice CT angiography (CTA) of intracranial and cervical arteries.Materials and Methods Sixty patients with head and neck CTA were recruited prospectively,and they were randomly divided into group A and group B.The scan parameters of the two groups were identical,but the protocol of contrast medium injection was different.Group A was injected 60 ml contrast medium and 30 ml saline successively with the rate of 4.0 ml/s.Group B was injected 30 ml contrast medium and 50 ml saline successively with the rate of 5.0 ml/s.CT attenuation values of aortic arch,common carotid artery,subclavian artery,cerebral middle artery,superior vena cava,innominate vein,subclavian vein,internal jugular vein were measured,and the image quality was evaluated.Results The average CT values of superior vena cava,right innominate vein,right subclavian vein in two groups had significant differences (P＜0.05).The average CT values of left brachial vein,left subclavian vein,left and right internal jugular vein in two groups had no significant differences (P＞0.05).The average CT values of aortic arch,left and right common carotid artery,left and right subclavian artery,left and right cerebral middle artery in two groups had significant differences (P＜0.05).The scores of image quality in two groups also had significant difference (P＜0.05).Conclusion Head-and-neck CTA with 30 ml low-dose contrast medium is feasible and the images are satisfactory for diagnosis,which can reduce the dose of contrast medium and accumulation of contrast medium in venous system,while maintaining enough artery enhancement.
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Objective To evaluate the applicability of activated charcoal in treatment of oral poisoning. Methods The feasibility of clinical manipulation and tastiness of 4 forms of activated charcoal were investigated, with different dosage forms in 35 nurses and 50 volunteers, respectively. The feasibility of the clinical manipulation was assessed by gastrelavage time and block numbers of stomach duet,and the tastiness by volunteers' taking orally. Results The gastrolavage time (151.8±17.8) s for powder, (96.9±24.80) s for suspension, (319.0±82.4) s for tablet and (314.3±93.3) s for suspension(P <0.001). Conclusion There are significant differences in the applicability of activated charcoal in different dosage forms. The suspension is the best form in feasibility. Capsule and tablet are better than powder and suspension in tastiness. Suspension and powder are the worst to accept.
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BACKGROUND: Cleistocalyx operculatus is a dried alsbastrum of myrtle. It is reported that cleistocalyx operculatus extracts can improve cardiac contraction through inhibiting the activity of Na+/K+-ATPase, and decrease rate of contraction. Do cleistocalyx operculatus extracts have the biological activity of antioxidation?OBJECTIVE: To observe the effects of cleistocalyx operculatus on oxidative injury of PC12 nerve cells induced by H2O2.DESIGN: Non-randomized controlled study.SETTING: State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology.MATERIALS: The experiment was conducted at New World Institute of Biotechnology, State Key Laboratory of Bioreactor Engineering of East China University of Science and Technology, from May to November 2002.Eight adult male Kunming mice were selected. PC12 nerve cells were supplied by Shanghai Cell Institute of the Chinese Academy of Sciences.METHODS: Model of oxygenic injury of PC12 nerve cells was estabPC12 cells were cultured in 96-well plates. Cleistocalyx operculatus was diluted with RPMI1640 culture medium into five concentrations of 0.001,0.01, 0.1, 0.5 and 1 g/L with 3 wells in each concentration; each well had 2×103 cells. Blank control group, or non-drug culture medium group, was set. Under the standard condition, cells were cultured for 48 hours and ascells were inoculated in 96-well plate with the density of 2×103 for 24-hour wall adhering, and then divided into normal control group (normal cell without H2O2 or cleistocalyx operculatus extracts), 0, 0.01, 0.1, 0.5 and 1 g/L cleistocalyx operculatus. Cells in all groups except normal control group were treated with 200 μmol/L H2O2 at 37℃ for 3 hours, then cleistocalyx operculatus of various concentrations was added and survival rate was asfree radicals: PC12 cells with oxygen-derived free radicals were treated in the same way as done for cell survival rate assay and measured with CDCFH staining method.fect of cleistocalyx operculatus extracts on intracellular and extracellular oxygen-derived free radicals in PC12 nerve cells induced by oxidative injury.operculatus could protect nerve cells; however, at 0.055-1.00 g/L the effect on cell growth did not significantly differ from that of blank control extracts had no protective effect on the injury of PC12 nerve cells induced by H2O2. At 1.00 g/L, it had strong plerosis for oxidative injury of PC12 and extracellular oxygen-derived free radicals in PC12 nerve cells was increased; however, at 0.01 g/L concentration of cleistocalyx operculatus extracts, the level was lower than that in model group.dation of membrane lipid of hepatic microsome, but also protect against oxcleistocalyx operculatus extracts is related to its concentration. At 1.00 g/L,it has great capacity of oxidation plerosis, and at 0.01 g/L it can decrease the level of oxygen-derived free radicals inside and outside cells.
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Objective To evaluate the arrival peak time (APT) of contrast medium to abdominal aorta at different dosages with 64-detector CT scanner.Methods Sixty cases with normal cardiac function were divided randomly into three groups(group A,B,C).The injection rate of group A,B,C was 4.5 ml/s,3.5 ml/s,4.5 ml/s respectively.A small test bolus and the enhancement dosage bolus were at the same injection rate.After the injection of contrast medium was done,20 ml saline chaser was followed in group A and B but group C.20 patients with cardiac dysfunction as group D received the same injection protocol as group A.The concentration of contrast medium was 370 mgI/ml and cine-modal was used in contrast-enhanced scanning.The time-density curve of abdominal aorta at the level of porta hepatic and APT were measured at the different group and the different dosage.Results APT of contrast medium of the small test bolus in group A,B,and C ranged from 19 s to 24 s with mean time(20?2) s,(19?3) s and(22?3) s respectively.In group D,APT ranged from 24 s to 42 s with mean time(28?14) s.APT of enhancement dosage ranged from 20 s to 26 s among group A, B,C with mean(22?3) s,(21?2) s and(24?2) s respectively.In group D,APT ranged from 26 s to 44 s,with mean time(32?14) s.The difference of APT between test bolus and enhancement dosage was 2~7 s among group A,B and C,and was 3~12 s in group D.Conclusion The APT of abdominal aorta at the level of porta hepatis between test bolus and enhancement dosage in the patients with normal cardiac function or with cardiac dysfunction is different.