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501.

Background  

Triple-negative breast cancers (TNBC) neither express hormone receptors, nor overexpress HER2. They are associated with poor prognosis, as defined by low five-year survival and high recurrence rates after adjuvant therapy. Overall, TNBC share striking similarities with basal-like breast cancers (BBC), so a number of studies considered them being the same. The purpose of this review is to summarise the latest findings on TNBC concerning its relation and delineation to BBC, discuss the developmental pathways involved and address clinical implications for this complex type of breast cancer.  相似文献   
502.
Background: Remodeling of onlay grafts combined with implants to the mandible results in predictable changes in the graft's radiographic density. We studied the relationship between changes in radiographic density and trabecular structure during the first year after onlay grafting with simultaneous implant placement to the mandible. Purpose: The aim of this study was to evaluate changes in bone structure after onlay grafting. Materials and Methods: Standardized extraoral radiographs were taken regularly of 16 mandibular sides. Bone structure was measured using the Carl Zeiss Vision KS 400 3.0 imaging system. The parameters studied were trabecular area and perimeter, cavity area and perimeter, end points, branching points, skeleton length, branch angle and direction, and texture. Results: No differences were found between measurements ventrally versus dorsally of the implant, nor close to versus away from the implant. Early cortical changes suggest partial resorption and formation of a more complex structure. In the fourth quarter after surgery, progressive resorption is seen in the graft's upper cortex. In the graft's upper spongiosa, most parameters indicate bone formation during the first postoperative year. Loading‐induced structure changes could not yet be found. Conclusion: The technique can be used to study changes in the architecture of bone grafts. Changes found in the graft's architecture are in accordance with changes in bone density.  相似文献   
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医学影像学是一门实践性很强的形象思维学科,如何合理应用多媒体技术手段开展现代医学影像学教学,本文就多媒体技术与传统板书教学的有机结合进行了有益的探讨。强调做好现代多媒体技术手段教学与传统教学的重要性是医学影像学教学一个值得重视和思考的问题。  相似文献   
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Summary We report the clinical, biochemical and molecular findings on the first documented patient with 4-hydroxybutyric aciduria (4-HBA, McKusick 271980) from Uruguay. The patient displayed a severe picture and turned out to be homozygous for a mutation (c.1226G < A) previously shown to be associated with null enzyme activity. Electronic supplementary material Supplementary material is available for this article at  相似文献   
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微小染色体维持(MCM)蛋白家族是一类从太古代生物到高等真核生物广泛存在的高度保守的蛋白质。MCM蛋白与其他相关因子相互影响,共同在DNA复制、延长、转录及修复过程中发挥作用。MCM蛋白在细胞周期中异常高表达意味着细胞非典型增生甚至肿瘤的发生,提示MCM蛋白可作为增殖细胞的特殊标志物,在肿瘤的诊断、预后评价、临床治疗等方面具有广泛的应用前景。  相似文献   
509.
Two previously healthy infants, a boy and a girl aged 3 and 4 months, respectively, were admitted for fever of unknown origin with laboratory results indicating an inflammation. The boy presented with vomiting, pyuria, anaemia, and thrombocytosis. The girl presented with irritability, erythema and diarrhoea. All viral and bacterial cultures remained negative and supplementary radiology was unable to detect a focus of infection. The fever had persisted for at least 12 days in both cases before the diagnosis 'atypical Kawasaki disease' was considered. Cardiac echograms showed dilatation of the coronary arteries in both patients and confirmed the diagnosis. Immediate therapy with intravenous immunoglobulins and acetylsalicylic acid was given, whereupon the fever subsided within 24 hours; the further clinical course was uneventful. These cases illustrate the fact that atypical Kawasaki disease is often a late consideration, especially when the symptoms of the classical form are absent. This condition should be considered in every infant presenting with long-lasting unexplained fever.  相似文献   
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