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924.
AD Kanner 《Canadian Metallurgical Quarterly》1976,44(5):802-805
Hypertension was observed in ten infants. Seven had thrombosis either of one renal artery or of both. The seven infants had previously had an indwelling catheter in the umbilical artery. One infant who had not had an indwelling umbilical arterial catheter had stenosis of a renal artery. No etiology for the hypertension was found in two infants, one of whom had had an umbilical arterial catheter. Response to antihypertensive medication was generally poor. Five of the infants died. We recommend prompt diagnostic evaluation in hypertensive infants. Nephrectomy should be considered, if the renal artery is occluded. Hypertension appears to be a life-threatening complication of umbilical arterial catheterization. 相似文献
925.
T Yamashita N Wu G Kupfer C Corless H Joenje M Grompe AD D'Andrea 《Canadian Metallurgical Quarterly》1996,87(10):4424-4432
Fanconi anemia (FA) is an autosomal recessive disease characterized by congenital anomalies, aplastic anemia, and cancer susceptibility. Mutations within the FA complementation group C (FAC) gene account for approximately 14% of diagnosed FA cases. Two mutations, one in exon 1 (delG322) and one in exon 4 (IVS4 + 4 A to T), account for 90% of known FAC mutations. The delG322 mutation results in a mild FA phenotype, while the IVS4 + 4 A to T mutation results in severe FA phenotype. To determine the molecular basis for this clinical variability, we analyzed patient-derived cell lines for the expression of characteristic mutant FAC polypeptides. All cell lines with the delG322 mutation expressed a 50-kD FAC polypeptides, FRP-50 (FAC-related protein), shown to be an amino terminal truncated isoform of FAC reinitiated at methionine 55. All cell lines with the IVS4 + 4 A to T mutation lacked FRP-50. Overexpression of a cDNA encoding FRP-50 in an FA(C) cell line resulted in partial correction of mitomycin C sensitivity. In conclusion, expression of an amino terminal truncated FAC protein accounts, at least in part, for the clinical heterogeneity among FA(C) patients. 相似文献
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RATIONALE AND OBJECTIVES: The authors determine the effectiveness of stereoscopy and vertical-axis rotation for displaying three-dimensional (3-D) information in x-ray images. METHODS: Simple x-ray images were simulated using ray tracing and computer-displayed in monoscopic static (MS), monoscopic rotating (MR), stereoscopic static (SS), and stereoscopic rotating (SR) formats. In two experimental tasks, participants including experts (radiologists and radiographers) were shown images displayed in these four formats. Performance was measured by participants' accuracy of judgment, amount of time taken, and confidence in each response. The experts also informally evaluated the displays using complex fluoroscopic skull images and a simulated diagnostic task. RESULTS: The results from both tasks were consistent and showed MS to be least effective and SR to be most effective on all measures. There was no difference in performance between the nonexperts and experts, whose informal feedback consolidated the experimental findings. CONCLUSIONS: It was found that rotational stereoscopic fluoroscopy is feasible and is an effective way of portraying 3-D information using x-rays. 相似文献
929.
GM K?nig AD Wright WJ Keller RL Judd S Bates C Day 《Canadian Metallurgical Quarterly》1998,64(7):612-614
The 3-hydroxy-3-methylglutaric acid (HMG) containing flavonoid glucoside chamaemeloside, has been determined to have in vivo hypoglycaemic activity comparable to that of free HMG. An improved isolation scheme for obtaining chamaemeloside from Chamaemelum nobile is presented. 相似文献
930.
OBJECTIVES: To describe the natural recovery of visuospatial neglect in stroke patients and the distribution of errors made on cancellation tests using a standardised neuropsychological test battery. METHOD: A prospective study of acute (< seven days) patients with right hemispheric stroke. Patients identified with visuospatial neglect were followed up for three months with monthly clinical and neuropsychological testing RESULTS: There were 66 patients with acute right hemispheric stroke assessed of whom 27 (40.9%) had evidence of visuospatial neglect. Patients with neglect, on admission, had a mean behavioural inattention test (BIT) score of 56.3, range 10-126 (normal>129). Three of the subtests identified errors being made in both the right and left hemispaces. During follow up, recovery occurred across both hemispaces, maximal in the right hemispace. Recovery from visuospatial neglect was associated with improvement in function as assessed by the Barthel score. At the end of the study period only six (31.5%) patients had persisting evidence of neglect. On admission the best predictor of recovery of visuospatial neglect was the line cancellation test (Spearman's rank correlation r=-0.4217, p=0.028). CONCLUSION: The demonstration of errors in both hemispaces has implications for the theory that neglect is a lateralised attentional problem and is important to recognise in planning the rehabilitation of stroke patients. 相似文献