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Detection of the Philadelphia chromosome in acute lymphoblastic leukemia by pulsed-field gel electrophoresis 总被引:1,自引:0,他引:1
The Philadelphia (Ph1) chromosome is an acquired abnormality in the malignant cells of 10% to 25% of patients with acute lymphoblastic leukemia (ALL). Unlike chronic myelogenous leukemia (CML), where the molecular detection of the Ph1 chromosome is relatively straightforward using conventional Southern hybridization analysis, the detection of the Ph1 chromosome in ALL is complicated by the existence of several molecular subtypes, and the fact that translocation breakpoints are dispersed over a large genomic area. To circumvent these difficulties, we investigated pulsed-field gel electrophoresis (PFGE) to determine if this method could be used directly on clinical samples to detect the Ph1 chromosome in ALL. We report that, in a study of seven patients with Ph1-positive ALL, we could easily detect the Ph1 using only a single PFGE analysis, regardless of the Ph1 subtype, and we could confirm that the translocations occur either within or very near the BCR gene in all seven. We conclude that PFGE is a useful technique for the detection of the Ph1 in ALL, which ultimately may find wide applicability in the detection of other chromosomal abnormalities in other malignancies. 相似文献
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The extent of length polymorphisms of the heterochromatic and euchromatic segment of the human Y chromosome were investigated in 15 boys with acute leukemia and were compared with 15 normal controls. A greater value of the Yh/F index in relation to controls was established (P < 0.05). The length of the euchromatic segment was also shorter in the patients than the controls (P < 0.05). 相似文献
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C. COSTALOS G. RUSSELL Q. AL RAHIM M. J. TARLOW D. J. LLOYD K. R. ROSS 《Acta paediatrica (Oslo, Norway : 1992)》1985,74(3):382-385
ABSTRACT. Serial plasma glucose estimations were performed in 44 light-for-date infants and 17 infants of diabetic mothers fed 2, 3 or 4-hourly with feeds containing 10 % additional carbohydrate in the form of a glucose polymer (Caloreen). In the infants fed 2 and 3-hourly, plasma glucose was higher following the high carbohydrate feeds, particularly immediately before the next feed was due. Given 4-hourly, the high carbohydrate feed had little effect in most light-for-date infants, and in one light-for-date infant and two infants of diabetic mothers the plasma glucose was lower at the end of 4 hours than following normal formula. It is concluded that the addition of glucose polymer to feeds given 2 and 3 hourly has a potentially useful effect in neonates at risk of developing hypoglycaemia, but it cannot be used to increase the feed interval to 4 hours. 相似文献
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A series of 73 hypopharyngeal (Zenker's) diverticula is reported and the choice of treatment and technique of excision are discussed. The problems of excision include operation on an infected site with limited access but few patients are unfit for the procedure. Preoperatively the sac should be packed and the oesophagus stented. The side of approach is unimportant as the condition is essentially midline. Cricopharyngeal myotomy appears to reduce the recurrence rate, possibly by improving coordination of pharyngeal contraction and upper oesophageal relaxation. The use of electrocoagulation is not recommended as 20% of patients require repeated general anaesthesia and the procedure fails in 13%. For all but the smallest pouches, excision is the treatment of choice. 相似文献
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Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献