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941.
Mary Scott Soo Phyllis J. Kornguth Ruth Walsh Charlotte Elenberger Gregory S. Georgiade David Delong Charles E. Spritzer 《Journal of magnetic resonance imaging : JMRI》1997,7(4):724-730
The objective of this study was to determine the frequency and significance of the MR findings of incomplete shell collapse for detecting implant rupture in a series of surgically removed breast prostheses. MR images of 86 breast implants in 44 patients were studied retrospectively and correlated with surgical findings at explanation. MR findings included (a) complete shell collapse (linguine sign), 21 implants; (b) incomplete shell collapse (subcapsular line sign, teardrop sign, and keyhole sign), 33 implants; (c) radial folds, 31 implants; and (d) normal, 1 implant. The subcapsular line sign was seen in 26 implants, the teardrop sign was seen in 27 implants, and the keyhole sign was seen in 23 implants. At surgery, 48 implants were found to be ruptured and 38 were intact. The MR findings of ruptured implants showed signs of incomplete collapse in 52% (n = 25), linguine sign in 44% (n = 21), and radial folds in 4% (n = 2). The linguine sign perfectly predicted implant rupture, but sensitivity was low. Findings of incomplete shell collapse improved sensitivity and negative predictive values, and the subcapsular line sign produced a significant incremental increase in predictive ability. MRI signs of incomplete shell collapse were more common than the linguine sign in ruptured implants and are significant contributors to the high sensitivity and negative predictive values of MRI for evaluating implant integrity. 相似文献
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Magnus Stangenberg Gran Lingman George Roberts Pinar Ozand 《American journal of medical genetics. Part A》1992,44(2):142-144
We report on fetal hydrops presenting at 18 weeks of gestation and diagnosed as β-glucuronidase deficiency. The parents were first cousins and there were 2 previous similar fetal deaths. β-Glucuronidase was absent in cultured fetal fibroblasts and lymphoblasts but was normal in the tested relatives. The activities of other lysosomal enzymes were normal. © 1992 Wiley-Liss, Inc. 相似文献
944.
Total fluorescence from arterial tissue is influenced by three factors: the absorption coefficient of tissue at a specific
excitation wavelength, the laser excitation power and the fluorescence coefficient which is related to chemical species in
tissue. These various influences were demonstrated by the following experimental results in vitro: (1) the effect of increasing
power on fluorescence intensity, (2) the total fluorescence intensity in normal aorta and plaque and (3) the effect of a chromophore
such as β-carotene on total fluorescence intensity. The fluorescence intensity of normal artery is an incremental function
of laser excitation power, and the fluorescence emission from normal artery compared to fluorescence emission from plaque
is significantly different at the same excitation power. The total fluorescence of normal artery was measured to be twice
as great as that of atheromatous plaque (relative mean ratio of 2.58±0.46 compared to unity,p<0.0002 at 488 nm; relative mean ratio of 2.57±0.51 compared to unity,p<0.0009 at 514 nm). The total fluorescence emission decreases with the increase of β-carotene content in arterial tissue (R=0.97). These emission differences, when intensified by an exogenous chromophore of β-carotene, may provide an improved guidance
signal for diagnosis of plaque from normal artery during laser angioplasty procedures. 相似文献
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949.
Berenice Mathisen Sheena Reilly David Skuse 《Developmental medicine and child neurology》1992,34(2):141-149
The oral-motor function of 10 infants with Turner syndrome and their age- and sex-matched controls were assessed during feeding. In addition to well-recognised dysmorphic features, including oral anomalies and high-arched palates, index infants had marked hypotonia of the cheeks and lips, dysfunctional tongue movements and poorly developed chewing skills. Their meal-times were significantly shorter than those of the controls and they weighed significantly less at six, 12 and 15 months. All mothers of infants with Turner syndrome complained of difficulties feeding their children and these problems often had been present since birth. 相似文献
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