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1.
Synovial haemangioma of the knee: a frequently misdiagnosed lesion   总被引:2,自引:0,他引:2  
Objective The objective of this study was to assess the contribution of magnetic resonance (MR) imaging in the diagnosis and surgical planning of five cases of synovial haemangioma of the knee.Patients and Methods The clinical, radiological and arthroscopic features of five pathologically proven synovial haemangiomas of the knee were retrospectively reviewed.Results A diagnostic delay, on average of 8 years, had occurred in four of the cases. Plain films were unremarkable, except for one case with arthropathy mimicking haemophilia, Arteriography, performed in three patients, was normal in one. CT, performed in three patients, showed the lesion, but the extent of the latter was better demonstrated with MR imaging. Synovial haemangiomas had a high signal intensity on T2-weighted images, without any extensive mass effect. Fibrofatty septa within the lesion were observed in three cases and muscular and/or fatty invasion in two. Arthroscopy allowed diagnosis of the lesion in two cases, but showed only non-specific synovitis in another two.Conclusion This study emphasizes the valuable contribution of MR imaging in the diagnosis and surgical planning of synovial haemangiomas.  相似文献   
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This study examines risk factors for mortality on a three years follow-up, in a sample of 645 subjects 60 years and over, living in a rural area in Haute-Garonne. Basic data were collected by interview in a transversal survey in 1982 and three years later 68 persons had died. The assessment of relative risk factors illustrates the important role of disabilities (RR = 5.3), of self-evaluation of health, and of degree of enthusiasm for life; but there is no statistical relationship between mortality and social support, or number of diseases. A discriminant analysis, indicates that disabilities and subjective assessment of health seem to be independent predictors of mortality. A "mortality risk indicator" including nine components, can identify people who have a high risk of dying within three years, with a sensitivity of 77% and specificity of 78%.  相似文献   
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Summary To study the antenatal differentiation of the human intervertebral disc, the columns of forty eight embryos and fetuses were examined histologically. The primitive disc is composed of two structures: the notochord which shows a progressive expansion into the disc, and the fibrocartilaginous perinotochordal disc. No histological sign of interaction between notochordal and perinotochordal cells, which may explain the notochordal expansion into the discs, was seen. On the other hand, the notochordal intervention in the cartilaginous differentiation of the inner zone is probable.
Différenciation anténatale du disque intervertébral humain
Résumé Cette étude de la différenciation anténatale du disque intervertébral humain repose sur l'examen de coupes histologiques de quarante huit colonnes vertébrales d'embryons et de foetus. Le disque primitif est composé de deux structures : la notochorde, qui présente une expansion progressive de son diamètre au sein du disque, et le disque périnotochordal, d'abord mésenchymateux puis fibrocartilagineux. Il n'a pas été mis en évidence de signe histologique témoignant d'une interaction entre les cellules notochordales et les cellules périnotochordales qui puisse expliquer l'expansion de la notochorde au sein des disques. Le rôle de la notochorde dans la différenciation cartilagineuse de la zone centrale est par contre probable.
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Transferrin-polycation conjugates as carriers for DNA uptake into cells.   总被引:27,自引:14,他引:13       下载免费PDF全文
We have developed a high-efficiency nucleic acid delivery system that uses receptor-mediated endocytosis to carry DNA macromolecules into cells. We accomplished this by conjugating the iron-transport protein transferrin to polycations that bind nucleic acids. Human transferrin, as well as the chicken homologue conalbumin, has been covalently linked to the small DNA-binding protein protamine or to polylysines of various sizes through a disulfide linkage. These modified transferrin molecules maintain their ability to bind their cognate receptor and to mediate efficient iron transport into the cell. The transferrin-polycation molecules form electrophoretically stable complexes with double-stranded DNA, single-stranded DNA, and modified RNA molecules independent of nucleic acid size (from short oligonucleotides to DNA of 21 kilobase pairs). When complexes of transferrin-polycation and a bacterial plasmid DNA containing the gene for Photinus pyralis luciferase are supplied to eukaryotic cells, high-level expression of the luciferase gene occurs, demonstrating transferrin receptor-mediated endocytosis and expression of the imported DNA. We refer to this delivery system as "transferrinfection."  相似文献   
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OBJECTIVE: The purpose of this study was to compare the diagnostic efficacy of low- and high-field-strength MR imagers in the diagnosis of anterior cruciate ligament tears and meniscus tears. SUBJECTS AND METHODS: In 219 patients with suspected internal derangement of the knee, MR imaging at 0.2 and 1.5 T was performed with similar sequences. Only patients with surgically confirmed diagnosis (n = 90) were included in the statistical analysis. Radiologists were unaware of diagnosis and field strength. Sensitivity, specificity, diagnostic accuracy, and inter- and intraobserver variability were determined. RESULTS: There was excellent correlation between the field strengths in accuracy, sensitivity, and specificity for anterior cruciate ligament and meniscus tears. Accuracy for medial meniscus, lateral meniscus, and anterior cruciate ligament tears was 91-93%, 88-90%, and 93-96%, respectively, at 0.2 T and 91-94%, 91-93%, and 97-98%, respectively, at 1.5 T. Inter- and intraobserver variability values showed excellent correlation (kappa > 0.8). CONCLUSION: The level of diagnostic accuracy in anterior cruciate ligament tears and meniscus tears is comparable for low- and high-field-strength MR imagers.  相似文献   
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Primary vertebral osteosarcoma is a rare type of osteosarcoma, differing from the appendicular forms by an incidence peak occurring at a higher age and a poorer prognosis, due to the difficulties of the surgical treatment. We present five cases of histologically proven primary vertebral osteosarcomas followed in our institution between 2004 and 2012. They allow to illustrate some essential radiologic features, useful to evoke this rare entity.  相似文献   
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There is conflicting clinical evidence whether administration of coenzyme Q10 (CoQ10) improves function following coronary artery bypass graft surgery (CABG). Using a swine model of hibernating myocardium, we tested whether daily CoQ10 would improve contractile function by MRI at 4-week post-CABG. Twelve pigs underwent a thoracotomy and had a constrictor placed on the left anterior descending (LAD). At 12 weeks, they underwent off-pump bypass and received daily dietary supplements of either CoQ10 (10 mg/kg/day) or placebo. At 4-week post-CABG, circumferential strain measurements in the hibernating LAD region from placebo and CoQ10 groups were not different and increased to a similar extent with dobutamine (?14.7?±?0.6 versus ?14.8?±?0.1, respectively (NS)). Post-sacrifice, oxidant stress markers were obtained in the mitochondrial isolates and protein carbonyl in the placebo, and CoQ10 groups were 6.14?±?0.36 and 5.05?±?0.32 nmol/mg, respectively (NS). In summary, CoQ10 did not improve contractile reserve or reduce oxidant stress at 4-week post-CABG.  相似文献   
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