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排序方式: 共有445条查询结果,搜索用时 15 毫秒
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Gerhard H. Mostbeck Matthias C. Dulce Gary R. Caputo Evelyn Proctor Charles B. Higgins 《Journal of magnetic resonance imaging : JMRI》1993,3(4):617-623
The sites of deposition of atherosclerotic plaque on the aortic wall are considered to be influenced by secondary and retrograde flow patterns that cause regions of altered shear stress. To detect secondary flow patterns and areas of retrograde flow in the abdominal aorta, velocity-encoded cine (VEC) magnetic resonance (MR) imaging was performed at five different levels of the abdominal aorta in nine healthy volunteers. Net retrograde flow (expressed as a percentage of antegrade flow) increased from proximal to distal levels and was maximal (13.8% ± 11.8) just distal to the origin of the renal arteries. An increase in the duration of retrograde flow over the cardiac cycle was observed from proximal to distal levels. Whereas retrograde flow was present at end systole and early diastole in each volunteer at every level, the duration and amount of retrograde flow during diastole showed high interindividual variation. Such differences suggest the possibility of variable vascular geometric risk factors in the population for the development of atherosclerotic plaque. The location of retrograde flow in the abdominal aorta demonstrated in vivo with VEC MR imaging was close to that obtained with in vitro flow visualization studies in models of the abdominal aorta. 相似文献
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'The Closer'-percutaneous vascular suture device: evaluation of safety and performance in neuroangiography 总被引:10,自引:0,他引:10
Henk CB Grampp S Heimberger K Czerny C Schindler E Mostbeck GH 《European journal of radiology》2003,48(3):237-243
OBJECTIVE: To evaluate the use of the suture mediated vascular closure device concerning practicability and safety in clinical angiography practice. MATERIAL AND METHODS: One hundred and seventeen patients (59 female, 58 male, mean age 40.9+/-13.4) underwent percutaneous closure of common femoral arterial puncture sites following diagnostic neuroangiography using the suture device 'the Closer' (Perclose Inc., Redwood City, CA, USA). Primary success, early problems (within 24 h) and late complications were evaluated. Complications were graded as minor and severe with or without need of surgical intervention and categorized by type. Parameters such as age, gender, sheath size and number of previous arterial punctures were evaluated with respect to complications. RESULTS: Percutaneous closure was primary successful in 85% (100/117). The overall complication rate was 32% (28% mild n=35, 4% severe n=6, which needed surgical intervention). All but one problem occurred within the first 24 h after the suture. Additional manual compression was necessary in 32 cases (25%). There was no significant difference in age and gender between the groups with and without complications. Sheath size was significantly larger (P<0.01) and numbers of preceeding angiograms were significantly higher (P<0.01) in the complications group compared with uncomplicated cases. CONCLUSION: The evaluated percutaneous vascular suture device is useful in clinical practice but limitations concerning patient selection seem to emerge in order to avoid complications. 相似文献
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Excel97在药物分析中的应用 总被引:1,自引:0,他引:1
目的:在药物分析中,电子表格软件MicrosoftExce197for Windows。方法:利用Excel的数据处理功能,进行药物的图表绘制、数据计算和统计处理,回归分析,特别是计算分析,并可建立分析数据库。结果和结论:Excel操作简单,功能强大,数据分析工作直观。 相似文献
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Objective : This study was carried out to evaluate the significance of amniotic fluid protein ingestion and absorption on fetal growth.
Methodology : Neonates with small bowel atresia during a 30 year period were studied retrospectively.
Results : There were 56 patients enlisted, 17 with duodenal atresia, 18 with jejunal atresia and 21 with ileal atresia. The percentage of mothers with polyhydramnios and the percentage of premature babies decreases as the intestinal atresia becomes more distal. The mean gestational age and the mean birthweight increase as the intestinal atresia becomes more distal. On the other hand, the percentage of the neonates with birthweight below the 50th and the 10th percentiles do not differ significantly as the intestinal atresia becomes more distal.
Conclusions : It appears that the variation of birthweights in babies with different levels of small bowel atresia may be due to the difference in gestation caused by polyhydramnios. The effect of amniotic fluid protein absorption on fetal bodyweight could not be demonstrated clinically in this study. 相似文献
Methodology : Neonates with small bowel atresia during a 30 year period were studied retrospectively.
Results : There were 56 patients enlisted, 17 with duodenal atresia, 18 with jejunal atresia and 21 with ileal atresia. The percentage of mothers with polyhydramnios and the percentage of premature babies decreases as the intestinal atresia becomes more distal. The mean gestational age and the mean birthweight increase as the intestinal atresia becomes more distal. On the other hand, the percentage of the neonates with birthweight below the 50th and the 10th percentiles do not differ significantly as the intestinal atresia becomes more distal.
Conclusions : It appears that the variation of birthweights in babies with different levels of small bowel atresia may be due to the difference in gestation caused by polyhydramnios. The effect of amniotic fluid protein absorption on fetal bodyweight could not be demonstrated clinically in this study. 相似文献