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981.
Observations on two members of the Swedish family with congenital dyserythropoietic anaemia,type III
S. N. Wickramasinghe A. Wahlin D. Anstee S. F. Parsons G. Stopps I. Bergstrom M. Eriksson H. Sandstrom S. Shiels 《European journal of haematology》1993,50(4):213-221
Abstract: Two affected individuals of the Swedish family with CDA, type III, in which the disease is transmitted as an autosomal dominant character, were studied. Both cases displayed features hitherto undescribed in this family but described in patients with CDA, type III, in whom the inheritance may have been as an autosomal recessive character. Such features were: (a) haemosiderinuria, (b) grossly disorganised erythroblast nuclei, (c) differences in the ultrastructural appearances of individual nuclei within the same multinucleate erythroblast and (d) intraerythroblastic inclusions resembling precipitated globin chains. In both cases the giant mononucleate erythroblasts and the multinucleate erythroblasts had total DNA contents up to 28c (1c = haploid DNA content) and 48c respectively, and some DNA synthesising bi- and multinucleate erythroblasts contained one or more nuclei which were unlabelled with 3H-thymidine. These findings are similar to those in patients with the autosomal recessive type of disease. Thus no major phenotypic differences are yet apparent between cases of CDA, type III, with different patterns of inheritance. Analysis of the surface erythrocyte proteins of the 2 Swedish CDA, type III, patients with monoclonal antibodies recognising Band 3, glycophorins A, B, C and D, Rh, CD44, CD47, CD55, CD58, CD59, Lutheran, Kell, LW and acetylcholinesterase did not reveal any gross abnormality of expression of these proteins. A slightly altered expression of blood group antigens A and H was revealed by the lectins Dolichos biflorus and Ulex europaeus and the Mr of Band 3 as judged by SDS polyacrylamide gel electrophoresis was also slightly reduced, suggesting that there may be minor alterations in the degree of N-glycosylation of some red cell membrane constituents. 相似文献
982.
颈动脉间隙肿瘤的MRI诊断 总被引:5,自引:0,他引:5
目的:探讨颈动脉间隙肿瘤的MRI影象特征及其病理、解剖学基础和诊断价值。材料和方法:分析25例颈动脉间隙肿瘤的MRI征象,并与手术病理或血管造影比较。结果:多数肿瘤的病理改变或血管造影的特征能在MRI图像上反映,囊变和含丰富粘液的神经源性肿瘤T2加权像呈边界光滑的极高信号,化学感受器瘤瘤内的血管表现为扭曲条状和圆点状的极低信号,颈内动脉瘤信号分层,转移瘤边界毛糙或不清;不同来源的肿瘤与颈内、外动脉或颈总动脉和颈内静脉的位置关系有解剖上的相关性,有利于准确的定位和鉴别诊断;25例中术前诊断正确22例(88%)。结论:MRI对颈动脉间隙肿瘤的定位和定性具有重要的诊断价值,结合病史可减少误诊。 相似文献
983.
人碱性成纤维细胞生长因子基因在大肠杆菌中的克隆与表达 总被引:1,自引:0,他引:1
应用DNA重组技术将编码人碱性成纤维细胞生长因子(bbFGF)的基因克隆至原核高效表达质粒pBV_(221)的启动子下游。SDS-SAGE、ELISA和NTT活性监测结果表明:该重组质粒pBV-hbFGF在大肠杆菌DH5α中,经42℃诱导后,可表达出有较高生物活性的hbFGF。 相似文献
984.
火器伤后胸心异物存留 总被引:8,自引:0,他引:8
目的:探讨火器伤后胸心异物存留摘除的指征、时机、方法及结果。方法:回顾性分析了39例火器伤后胸心异物存留摘除者的一般资料、临床表现、不同处理方法的选择及效果。结果:19例患者早期因凝固性血胸及肺持续漏气伴异物存留或异物存留伴胸腔及心包腔化脓性感染,在开胸清创时做了异物摘除;另20例患者为胸伤伤情恢复后单纯异物存留,因异物位于肺门、心脏及大血管旁或远期并发症等,而后期开胸异物摘除。结论:火器性胸部穿透伤后,因异物本身或其他原因所致早期并发症者,应在开胸清创的同时摘除异物;胸伤伤情恢复而单纯胸心异物存留,应选择性摘除或因并发远期并发症而摘除。 相似文献
985.
Masahiro Fujita Kazuhiko Ito Hiroshi Kawamoto Saburo Kashii Mihoko Norioka Sumie Monden Minoru Okuma 《European journal of haematology》1993,50(4):200-205
Abstract: A cell line, BAD05, derived from B lymphocytes of an adenosine deaminase (ADA; EC 3,5,4,4)-deficient patient could not proliferate in a serum-free medium containing 100 μmol/l deoxyadenosine. When BAD05 was cultured with ADA-positive fibroblasts, the proliferation of BAD05 was improved. BAD05 cell density increased when the initially mixed ratio of fibroblasts/BAD05 was 1/10 or higher, but decreased when the ratio was 1/20 or lower. Deoxyadenosine concentrations in the medium and ATP and deoxyATP (dATP) levels in the BAD05 were measured after 4 hours of coculture at initial BAD05 cell densities of 1 × 105and 1 × 106cells/ml. Deoxyadenosine concentrations in the medium decreased as the density of fibroblasts increased. The dATP level decreased as the mixed ratio rose. The ratio of fibroblasts/BAD05 rather than the cell density of fibroblasts had a larger effect on the dATP levels in BAD05. Under our experimental conditions, ADA-negative cells proliferated well when the ratio of ADA-positive cells/ADA-negative cells was over 1/10. 相似文献
986.
A consecutive series of six adult patients ranging in age from 29 to 53 years is presented. The clinical and radiological features in each patient are described. Attention is drawn to the features demonstrated on computed axial tomography. In only one patient, the first encountered, was surgical excision undertaken and histological verification obtained. One patient died before any form of treatment could be instituted. The remaining four patients were treated with antituberculous chemotherapy alone and their progress monitored by sequential computed tomography. The excellent response and good outcome in this conservatively treated group are documented. 相似文献
987.
Narendrakumar Venilal Morris Michael John Abramson Malcolm John Rosier Roger Peter Strasser 《The Journal of asthma》1996,33(6):425-439
The objective of this study was to evaluate clinical history and self-perception of severity as predictors of asthma severity. A short-term longitudinal study was conducted in a family practice in Melbourne, Australia, utilizing peak flow monitoring, medication diary, and self-administered asthma severity questionnaire. Seventy-two asthmatic subjects with a positive bronchodilator or exercise test, aged between 6 and 79 years, were studied. Symptom and treatment items were correlated with peak flow variability and minimal peak expiratory flow rate (PEFR). An asthma severity scale was generated using the partial credit version of Item Response Theory and the participants' severity scores were validated against lung function tests and medication usage. Quantitative modeling procedures were used to investigate the interrelationships of factors associated with peak flow variability. Severity scores demonstrated significant relationships with peak flow variability (partial r = 0.34) and treatment items. Self-perceived severity of asthma in the preceding 2 weeks showed significant association with peak flow variability (partial rho = 0.46) and minimal PEFR (rho = -0.41). The severity module of the Monash Respiratory Questionnaire is a valid and reliable instrument. The most important symptoms appear to be the frequency of use of bronchodilator and frequency of nocturnal attacks. A carefully structured clinical history in conjunction with the peak flow criteria of variability and minimal peak flow rate would be appropriate in the evaluation of asthma severity. Patients' self-perception of the severity of their asthma needs further evaluation. 相似文献
988.
An experimental study was conducted in guinea pigs for the predictive assessment of the beryllium alloy hazard in occupational exposure of the skin to beryllium compounds. Guinea pigs were sensitized to beryllium sulfate according to the maximized Magnusson and Kligman test, and challenged with beryllium alloys and metallic copper, beryllium and aluminum samples. Results showed a delayed skin hypersensitivity reaction in 30 to 60% of pre-sensitized guinea pigs challenged with copper-beryllium alloys and aluminum-beryllium alloy. An inflammatory follicular reaction was induced by copper in both controls and pre-sensitized guinea pigs. 相似文献
989.
Werner Spileers Guy A. Orban Hugo Maes Luc Missotten 《Documenta ophthalmologica. Advances in ophthalmology》1988,68(3-4):363-374
CMSS-VEPs are presented as a sensitive, non-invasive functional investigation technique of the visual function, applicable in clinical practice. New improvements of the technique are presented. The underlying neuronal mechanisms are discussed. The clinical use is illustrated in a case of optic neuritis. 相似文献
990.
目的 探讨普萘洛尔和低剂量兰索拉唑长期维持治疗对预防肝硬化门脉高压消化道出血的疗效。方法 1 1 9例肝硬化门脉高压患者随机分为 3组 :Ⅰ组 :给予口服普萘洛尔加上护肝治疗。Ⅱ组 :联合给予低剂量兰索拉唑和普萘洛尔。Ⅲ组 :仅给予护肝治疗。兰索拉唑维持服药 6个月 ,普萘洛尔及一般对症治疗维持 1年。观察治疗前后各组患者所伴发溃疡、门脉高压性胃病 (PHG)、急性胃黏膜病变 (AGML)情况 (发生率 ) ,各组消化道出血的复发率、门静脉直径 (PVD)、脾静脉直径 (SVD)的变化。结果 经 1年观察 ,结果显示 ,普萘洛尔组、联合治疗组、对照组出血的复发率分别为 1 5 0 %、2 2 %、48 5 % ,组Ⅰ、组Ⅱ复发率显著低于组Ⅲ ,同时 ,组Ⅰ与组Ⅱ间的差异有显著性意义。治疗可见组Ⅰ、组Ⅱ患者所伴发的溃疡、PHG、AGML明显改善 ,PVD、SVD缩小。结论 普萘洛尔组联合抑制酸维持治疗 ,可预防引起消化道出血多种病因 ,较单用普萘洛尔的疗效好 相似文献