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排序方式: 共有577条查询结果,搜索用时 15 毫秒
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Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
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Variability of skin temperature in the waking monkey 总被引:3,自引:0,他引:3
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Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
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急性有机磷农药中毒120例的救治 总被引:1,自引:0,他引:1
0 引言 近年来 ,我科在救治急性有机磷农药 (organophos-phorus,OP)中毒方面 ,积累了一些经验 ,现报告如下 .1 对象和方法1 .1 对象 本组 1 2 0例符合《急诊急救学》中的诊断标准 [1 ](男 2 9例 ,女 91例 ) ,年龄 1 .5~ 70岁 ,平均 2 8.6岁 .经口中毒 99例 ,经皮肤中毒 2 1例 .轻度中毒 1 5例 ,中度中毒 42例 ,重度 (含极重度 )中毒 6 3例 . 1 996年 39例 ,1 997年 43例 ,1 998年 38例 . DDV 79例 ,乐果 2 0例 ,混合性中毒 1 0例 ,水胺磷 3例 ,氧化乐果、 391 1、 1 0 5 9、对硫磷各 2例 ,敌百虫 1例 ,药名不详 1 0例 .服毒量 >2 5 … 相似文献
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Hargreaves MK Schlundt DG Buchowski MS Hardy RE Rossi SR Rossi JS 《Journal of the American Dietetic Association》1999,99(11):1392-1399
OBJECTIVE: To develop an algorithm for determining the stage of change for dietary fat intake in African-American women. DESIGN: We examined the relationships between stage of change, dietary fat intake, and associated eating behaviors and developed an assessment tool for placing subjects in their appropriate stage of change. SUBJECTS: Working class and middle-income African-American women in Nashville, Tenn; 174 in study 1 and 208 in study 2. STATISTICAL ANALYSES: Fat and fiber intake by stage of change was examined using multivariate analysis of variance. Hierarchical cluster analysis was performed using Ward's method. RESULTS: A significant difference in fat intake was noted between women trying to change their intake and those not trying to change in study 1 (P < .001) and study 2 (P < .03). Of those trying to change, only 34% (study 1) and 9% (study 2) of subjects reported fat intakes below the Healthy People 2000 goal of 30% of energy from fat. In study 1, cluster analysis identified 14 groups of foods that significantly separated subjects into not trying, noncompliant, and compliant categories. Compliant subjects ate out less; ate fewer snack foods and less chicken, meat, and fat; and ate more fruits, vegetables, breakfast foods, and low-fat products. These results led to development of the Eating Styles Questionnaire (study 2), which facilitated more appropriate placement of the noncompliant group in stages of change for dietary fat intake. APPLICATIONS/CONCLUSIONS: These data support the stage construct of the Transtheoretical Model for dietary fat reduction in African-American women. Moreover, the Eating Styles Questionnaire (ESQ) can improve determination of stage of change for this group of women. The ESQ can be used to diagnose the eating styles that contribute to a high-fat intake and help in the design of interventions to lower fat intakes. 相似文献