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991.
Surgically uncorrectable tricuspid valve disease in children is rare. However, when it happens the surgical options are very limited. Tricuspid valve replacement using a mechanical valve or stented bioprosthesis is impractical. Use of homografts in the “anatomic position” has its limitations. We report here the use of an extracardiac homograft connection between the right atrium and right ventricle in a 16-month-old boy in whom severe tricuspid valve stenosis developed after surgical repair of a complex ventricular septal defect associated with dextrocardia and anomalous systemic venous drainage. The patient remains well receiving no cardiac medication 12 months after the procedure.  相似文献   
992.
目的评价磁共振尿路成像(Magneticresonanceurography,MRU)对泌尿系疾病的诊断价值。方法对36例泌尿系疾病患者进行MRU检查,并结合临床手术、病理资料和其他影像学资料进行回顾性分析。结果36例患者中,均有MRU阳性结果,3例肾盂、肾盏癌,4例前列腺癌,8例前列腺增生症,2例输尿管癌定性、定位明确;9例肾盂、输尿管移行段梗阻定位明确,定性有帮助;10例输尿管下段梗阻中6例诊断明确,4例未能确诊。结论MRU在泌尿系疾病的诊断中,对肿瘤的定位、定性参考价值较高,对尿路梗阻定位诊断有价值,对定性诊断帮助有其局限性。  相似文献   
993.
The expression of the B-cell marker mb-1 (CD79a) in Hodgkin's disease   总被引:1,自引:0,他引:1  
Recent evidence indicates that membrane-bound immunoglobulin on B lymphocytes is associated with a molecule which comprises the products of the mb-1 and B29 genes. This molecule is a highly specific marker for B-cells, presumably because of its central functional role in antigen triggering, and has recently been clustered as CD79a at the 5th Leucocyte Workshop. Recently there has been controversy surrounding reports of B-cell antigen expression by Reed–Sternberg and related cells, and we have therefore studied 108 cases of Hodgkin's disease immunohistochemically using a novel antibody which detects mb-1 protein in paraffin sections. The results were compared with those achieved using antibody L26 to detect CD20. The mb-1 protein was present in the neoplastic cells in all 14 cases of lymphocyte predominance Hodgkin's disease studied, and CD20 immunoreactivity was also found in seven of the eight cases of this subtype studied. Of the non-lymphocyte predominance cases, 20% (19/94) expressed mb-1 and 30% (20/67) CD20 in the Reed–Sternberg cells, but the cells positive for either of these two markers usually constituted only a very small proportion of the neoplastic population. However, in occasional cases (one of 94 for mb-1 and five of 67 for CD20), more than 50% of the neoplastic cells expressed one or both B-cell antigens. These results confirm the B-cell origin of the neoplastic cells in lymphocyte predominance Hodgkin's disease, but they also indicate that, contrary to our previous study, mb-1 expression may occasionally be found in what appears, on histological grounds, to be other types of Hodgkin's disease.  相似文献   
994.
995.
In embryology, a persistent connection of the left superior vena cava to the left atrium rarely coexists with a coronary sinus. We herein report an unusual case of persistent left superior vena cava terminating in a left atrium with normal coronary sinus, which was revealed at the time of permanent pacemaker implantation after a second operation for recurrent left atrioventricular valve regurgitation. Because this anomaly had gone undiagnosed at the first operation, we were unable to diagnose it prior to the second operation, because the preoperative coronary angiogram clearly demonstrated a coronary sinus that was not dilated. We would have repaired the anomaly using a patch or other procedure had it been diagnosed before the second operation in order to prevent cyanosis or brain complications secondary to right-to-left shunting. One should always be on guard for this rare condition.  相似文献   
996.
The Sinding-Larsen and Johansson disease is a non-negligible cause of gonalgia among children of 10 to 14, often misinterpreted as « growing pain . The disease is a benign pathology of the lower pole of the patella which occurs preferentially in physically active children. Our study, carried out in conjunction with the medical department INSEP, is based on a literature review as well as an analysis of 14 cases over two years. The present work eventually led to the differentiation of four etiopathological categories accounting for all the radiochemical evolutions observed. At the origin of these four categories, two factors coexist: the local fragility (the presence of cartilage at the lower pole of the patella) and the trigerring factor, which is most often sports practice. This explains why among children practicing sports, even intensively, only few suffer from this disease.It is essential to know the different radiological aspects of the normal patella in children, in order not to misinterpret one of these aspects with the Sinding-Larsen and Johansson disease.Always benign, the Sinding-Larsen and Johansson disease can very seriously disturb the « careerof children, engaged in high-level sports activity, the average time of evolution being seven months.  相似文献   
997.
用聚焦层析结合DEAE-Sephadex A-50离子交换层析,从正常人肝浸液中分离得两个精氨酸酶同工酶组分.经聚丙烯酰胺凝胶电泳(PAGE)鉴定从聚焦层析得到的第一峰同工酶组分为一条蛋白带,第二峰具有精氨酸酶活性的蛋白组分的主要蛋白带也极明显。各蛋白质成分向阴极电泳的前后顺序与从聚焦层析洗脱的先后次序一致。两型同工酶的比活力分别约为2050U/mg及790U/mg。用SDS-PAGE检测两型同工酶均由两种亚基组成,且分子量近似。  相似文献   
998.
应用体外反搏治疗33例冠心病患者,治疗前后进行心功能检查比较,结果是肺水指数下降4.19%(P<0.05),心室射血时间增加7.74%(P<0.05),射血流速指数增加5.39%(P>0.05),系统血管阻抗降低16.97%(P<0.001),心排量增加10%(P<0.01),心搏量增加13.32%(P<0.01),心率减慢6.66%(P<0.05),心搏指数增加13.23%(P<0.05),心脏指数增加10.63%(P<0.01),说明心功能检查有较好改善。  相似文献   
999.
The presence or absence of retinal detachment, especially detachment of the macula, was the most critical parameter predicting visual outcome, and long duration of detachment worsened the prognosis (P=0.0084). In contrast, the time interval from vitreous haemorrhage to surgery did not associate with the long-term visual outcome. Pre-operative visual acuity of counting fingers 1 m or better was associated with favourable visual outcome (P=0.0032). Other pre- or per-operative parameters (e.g. aphakia, iris rubeosis, extent of photocoagulation, retinal breaks) did not associate with visual prognosis significantly.Significant association between general parameters and visual outcome was found only in the group of traction retinal detachment where loss of vision was related to shorter duration of diabetes (P=0.0213), and shorter duration of background retinopathy (P=0.0300), and proliferative retinopathy (P=0.0072).  相似文献   
1000.
When dealing with patients with periodontal disease of variable severities, dentists must often choose between treating and restoring the involved tooth or indicating its extraction. Different criteria have been adopted in this decision-making process. The purpose of this study was to evaluate the criteria adopted by dentists to indicate the extraction of teeth with periodontitis. Dentists were interviewed at their private practices in three cities of the state of Rio Grande do Sul, Brazil. The evaluated criteria included severity of attachment loss, tooth mobility, furcation involvement, prosthetic planning, periodontal-endodontic lesion, possible systemic involvement due to the presence of periodontitis, referral to a periodontist for evaluation, radiographic bone loss greater than 50%, presence of extensive caries, socio-economic and cultural status of the patient, among others. The most often adopted criteria to indicate the extraction of periodontally affected teeth were the presence of mobility (37.5%), severity of attachment loss (24.3%) and radiographic bone loss greater than 50% (21.2%). The results of the present study demonstrated the difficulties faced by dentists to indicate the extraction of teeth with severe attachment loss, in addition to the establishment of an adequate prognosis. Aspects associated with the past disease were still the most often reported to indicate the extraction of teeth for periodontal reasons.  相似文献   
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