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排序方式: 共有1108条查询结果,搜索用时 18 毫秒
81.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
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E L McQuaid S J Kopel J H Nassau 《Journal of developmental and behavioral pediatrics : JDBP》2001,22(6):430-439
This study is a meta-analytic review of the behavioral adjustment of children and adolescents with asthma. Of 78 studies initially reviewed, 26 studies (encompassing 28 data sets), reflecting data on nearly 5,000 children with asthma (mean age = 8.4 years; 40% female), met criteria for inclusion. Effect size estimates were calculated across studies using standard methods. Separate effect sizes were calculated for internalizing and externalizing behavioral problems, degrees of asthma severity, and differences in control group used (i.e., sample controls or normative data). Results indicate that children with asthma have more behavioral difficulties than do healthy children, with the effect for internalizing behaviors being greater than that for externalizing behaviors (d(mn) = .73 vs .40). Increased asthma severity was associated with greater behavioral difficulties. Results did not differ by comparison group (healthy controls vs normative data). The findings suggest that patients with asthma, particularly children with severe asthma, should be considered at higher risk for behavioral difficulties that may necessitate psychosocial intervention. 相似文献
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Digital imaging of the chest 总被引:4,自引:0,他引:4
Fraser RG; Sanders C; Barnes GT; MacMahon H; Giger ML; Doi K; Templeton AW; Cox GG; Dwyer SJ d; Merritt CR 《Radiology》1989,171(2):297-307
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented. 相似文献
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Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献