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941.
Rhabdomyosarcoma is the most common primary orbital malignancy of childhood. It can present insidiously, mimicking other (benign) processes clinically and radiographically. CT and MR imaging are crucial in the diagnostic evaluation, treatment planning, and follow-up monitoring of the disease. Such imaging, especially when contrast is used, can accurately detect and state the extent of tumor involvement. 相似文献
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R Romeo M Colombo M Rumi R Soffredini E Del Ninno MF Donato A Russo P Simmonds 《Canadian Metallurgical Quarterly》1996,3(4):183-190
The NOD mouse is known as a spontaneous model of insulin-dependent diabetes mellitus. Fetuses in this strain present anomalies of the viscera, and the incidence increases in fetuses from dams with clinically manifested diabetes. To examine the role of maternal diabetes and the genetical influence in inducing heterotaxy, NOD dams were mated with males of the ICR strain (the original strain of the NOD) and with C57BL/6J sires (not genetically related to the NOD). The frequency of visceroatrial heterotaxy in fetuses from diabetic dams varied with the fetal genotype, being 65% (33/51) in NODxNOD (dam X sire, respectively), 24% (12/50) in NODxICR, and 7% (4/57) in NODxC57BL/6J. The cases with heterotaxy showed a tendency toward right isomerism of the viscera and had severe cardiac defects, such as endocardial cushion defect and double-outlet right ventricle or transposition of the great arteries. The fetal body weight from diabetic dams in each mating was lower than that from non-diabetic dams (P < 0.05), suggesting that maternal diabetes, rather than abnormal situs, is the main determinant for decreased fetal growth. These findings demonstrate that the liability to heterotaxy induced by maternal diabetes is influenced by the fetal genotype. 相似文献
946.
Potentiometric evaluation of ionic concentrations in physiological media has been reported to be significantly affected by the albumin containing matrix. Previous studies have attempted to clarify the origin of different patterns of variation of E versus albumin concentration at a constant 0.01 mol dm-3 KCl, depending on the experimental methodologies. This paper reports on measurements of K+ in albumin (BSA) containing KCl solutions, which have been pursued following different methodologies concerning the sequence of measurements, i.e., starting either from the most concentrated solution (100 g dm-3) (A) or from the most dilute solution (20 g dm-3) (B), and solution preparation, (a) dilution of an initial 100 g dm-3 albumin solution by successive addition of 0.01 mol dm-3 KCl, (b) concentration of an initial 20 g dm-3 albumin solution by addition of solid substance, (c) independent preparation of each albumin solution (20, 40, 60, 80 and 100 g dm-3) or (d) preparation of each albumin solution from direct dilution of a 100 g dm-3 stock solution with 0.01 mol dm-3 KCl. Convenient calculations were made and showed a significant contribution of albumin to the liquid-liquid junction potential. The variation of potential with albumin concentration is smaller for hypertonic than for isotonic bridge solutions, both for the dilution series (A,a and A,d) and for the concentration series (B,c and B,d). When the method for increasing the concentration is performed by addition of a solid substance to an initially diluted albumin (B,b), the slope of the E versus albumin concentration plot is larger for hypertonic than for isotonic reference electrolytes. This latter finding is in agreement with Payne's results when ultrafiltration was used to concentrate a protein solution. These observations are a clear indication that the method of preparation of concentrated protein solutions may significantly affect the results. 相似文献
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948.
MF Collen 《Canadian Metallurgical Quarterly》1976,3(2):197-204
Pulmonary blastoma is now accepted as a distinctive neoplasm. It remains rare, and only 28 cases have been reliably recorded. A further two cases are now reported, and the previous literature is reviewed. There are no specific clinical or radiological features of pulmonary blastoma. The presentation can be that of any other pulmonary tumour although a peripheral situation is usual and a large size is often attained before detection. Pulmonary blastoma is a mixed tumour with malignant epithelial and connective tissue components with a distinctive resemblance to fetal lung. The treatment of choice is surgical excision but the overall prognosis is poor. It is doubtful whether the tumour has a true blastomatous origin. 相似文献
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