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The serum erythropoietin (EPO) concentration in patients with myelodysplasia (MDS) varies widely at similar hemoglobin concentrations, although the reasons for this variation are unclear. We have studied the pharmacokinetics of an i.v. bolus of recombinant human EPO in ten subjects with myelodysplasia. Basal serum EPO concentration varied from 210 to 5984 mU/ml. Plasma half-time clearance (t1/2) varied from 3.9 to 20.0 h. A significant positive correlation was found between t1/2 and basal EPO concentration. An increase in immature peripheral blood reticulocytes was found on days 1 and 2 after EPO treatment; this may represent either an effect on hemopoiesis or on reticulocyte release from the bone marrow. 相似文献
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We report here the development of anti-Fy5 in a young Negro female with sickle cell disease. The antibody was responsible for a delayed hemolytic transfusion reaction. We believe this is the first report of such an antibody in Europe. 相似文献
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目的检测颅咽管瘤组织中DNA拓扑异构酶Ⅱα(DNATopoⅡα)的表达情况,分析其表达与肿瘤复发的关系,探讨其是否可作为判定颅咽管瘤预后的一个有效指标。方法设计前瞻性队列研究方案,采用免疫组化方法和图像分析技术测定63例颅咽管瘤组织切片中DNA拓扑异构酶Ⅱα的表达水平,评价颅咽管瘤釉质上皮瘤与鳞状乳头瘤病理亚型、复发组与非复发组、原发组与复发组之间肿瘤细胞的增殖能力。结果32例釉质上皮瘤14例复发,31例鳞状乳头瘤6例复发;釉质上皮瘤与鳞状乳头瘤病理亚型之间以及复发组与非复发组肿瘤之间DNA拓扑异构酶Ⅱα的表达水平有显著性差异(P<0.05),而原发组与复发组肿瘤之间DNA拓扑异构酶Ⅱα的表达水平无统计学差异(P>0.05)。结论颅咽管瘤的病理亚型以及DNA拓扑异构酶Ⅱα的表达水平与肿瘤的预后和复发有关,可作为预测肿瘤复发危险性的一个参考指标;DNA拓扑异构酶Ⅱα的表达水平在原发组和复发组肿瘤之间无显著性差异,提示肿瘤在复发过程中瘤细胞的增殖活性无明显变化。 相似文献
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Experimental microvascular growth plate transfers. Part 2--Investigation of feasibility 总被引:1,自引:0,他引:1
C V Bowen B M O'Brien G J Gumley 《The Journal of bone and joint surgery. British volume》1988,70(2):311-314
We investigated the feasibility in the dog of using transfers of the distal ulna into the radius either as growth plate replacements or as accessory growth plates in the diaphysis. Preliminary work determined the most satisfactory method of skeletal fixation. The experimental study showed that transfers used as growth plate replacements grew at almost normal rates, uniting with the recipient bone in a mean of 7.1 weeks. Transfers into the diaphysis initially nearly doubled the growth rate of the radius, although in the long-term results were unsatisfactory, because of fracture of the graft after a mean period of 8.2 weeks. 相似文献
17.
S Falcone R M Quencer B Bowen J H Bruce T P Naidich 《AJNR. American journal of neuroradiology》1992,13(1):403-406
The authors present two biopsy-proved cases of Creutzfeldt-Jakob disease. MR appears to be more sensitive than CT in detecting pathologic changes; signal abnormalities, when found, are predominantly within gray matter and may involve only peripheral cortex. 相似文献
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P E Bowen S Mobarhan C Henderson M Stacewicz-Sapuntzakis H Friedman R Kaiser 《JPEN. Journal of parenteral and enteral nutrition》1988,12(5):484-489
We have found that 12 patients requiring permanent enteral feeding secondary to cerebrovascular accident with adequate Vitamin A nutritional status had serum concentrations of various carotenoids which were only 8-17% of sex- and age-matched healthy controls. Their serum retinol levels were normal, but only 61% of their controls despite receiving two to three times the recommended daily allowance (RDA) in retinol equivalents. Commercial enteral formulas were found to contain only negligible quantities of the carotenoids and were the cause of the hypocarotenemia. To assess the ability of these patients to absorb beta-carotene, nine tube-fed patients were given 15 mg of beta-carotene (2.5 times the RDA) in a single dose. Serum concentration time curves showed that only four patients absorbed significant quantities of the beta-carotene and absorption was delayed compared to previously studied subjects taking enteral formulas as meals. These studies suggest that the efficiency of absorption of the fat soluble vitamins may be lower in tube-fed patients and that patients receiving long-term tube feeding are denied the possible protective effects of the carotenoids normally contained in the American diet. 相似文献
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