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Symptomatic lower limb ischaemia in endurance athletes and competitive cyclists is usually due to iliac artery compression syndrome. We report the cases of two competitive cyclists who presented with thigh claudication, with no previous cardiovascular or thrombo-embolic risk factors. They both had normal conventional and sports exercise tests. Further investigations revealed flush occlusion of the profunda femoris artery, believed to be due to dissection. Both patients improved with graduated exercise. We recommend contrast-enhanced MRA as the investigation of choice for this previously unreported condition.  相似文献   
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Pelizaeus–Merzbacher disease (PMD) is caused in most cases by either duplications or point mutations in the PLP1 gene. This disease, a dysmyelinating disorder affecting mainly the central nervous system, has a wide clinical spectrum and its causing mutations act through different molecular mechanisms. Eighty‐eight male patients with leukodystrophy were studied. PLP1 gene analysis was performed by the Multiplex Ligation‐dependent Probe Amplification technique and DNA sequencing, and, in duplicated cases of PLP1, gene dosage was completed by using array‐CGH. We have identified 21 patients with mutations in the PLP1 gene, including duplications, short and large deletions and several point mutations in our cohort. A customized array‐CGH at the Xq22.2 area identified several complex rearrangements within the PLP1 gene region. Mutations found in the PLP1 gene are the cause of PMD in around 20% of the patients in this series.  相似文献   
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Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with homologies to endopeptidases, on the X-chromosome), are responsible for X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has raised important questions regarding PEX function at the molecular level. The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function. Primers flanking 22 characterised exons were used to amplify DNA by PCR, and SSCP was then used to screen for mutations. Deletions, insertions, nonsense mutations, stop codons and splice mutations occurred in 83% of families screened for in all 22 exons, and 51% of a separate set of families screened in 17 PEX gene exons. Missense mutations in four regions of the gene were informative regarding function, with one mutation in the Zn2+-binding site predicted to alter substrate enzyme interaction and catalysis. Computer analysis of the remaining mutations predicted changes in secondary structure, N-glycosylation, protein phosphorylation and catalytic site molecular structure. The wide range of mutations that align with regions required for protease activity in NEP suggests that PEX also functions as a protease, and may act by processing factor(s) involved in bone mineral metabolism.   相似文献   
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WHO生存质量评估简表的等价性评价   总被引:20,自引:0,他引:20  
目的评价WHO生存质量评估简表(WHOQOL-BREF)在13个国家的等价性。方法采用多组验证性因子分析方法,对世界卫生组织生存质量研究小组提供的13个国家的数据进行分析,评价WHOQOL-BREF不同国家的等价性。结果各个国家的各个领域的Cronbachα系数均大于0·7,分布在0·7至0·88之间。除了英国和挪威之外,其它国家的社会关系领域的Cronbachα系数均大于0·65。采用根据世界卫生组织生存质量研究小组研制量表时构建的四因子模型对数据分别进行拟合,拟合优度指数(CFI)均大于0·8,其中德国、西班牙和美国的拟合优度指数大于0·9。多组验证性因子分析发现模型拟合尚可,CFI等于0·88,各个国家的因子负荷不全相等,因子负荷的轮廓相似。结论WHOQOL-BREF在13个国家具有相同的因子结构,且有等价性。  相似文献   
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Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
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BACKGROUND AND PURPOSE: To prospectively evaluate long-term urinary, bowel and sexual function after I-125 brachytherapy for localised prostate cancer using patient administered validated Quality of Life (QoL) instruments. MATERIALS AND METHODS: Between March 1995 and March 2004, 673 men underwent brachytherapy and recorded urinary symptoms prospectively using the International Prostate Symptom Score (IPSS). In addition, in a subgroup of 116 patients, the Expanded Prostate Cancer Index Composite (EPIC) was used to record QoL information on urinary, bowel and sexual function before treatment and at regular time intervals for at least two years. RESULTS: Initially, there was a sharp rise in urinary symptoms which was most marked within the first three months. Scores then resolved slowly and returned to within one or two units of pre-treatment level at one year. Subsequently, there was no significant deterioration in urinary symptoms up to nine years following brachytherapy. Few had significant bowel symptoms. Sexual function deteriorated initially and then improved but failed to return to pre-treatment levels by two years. Patients requiring neo-adjuvant hormones experienced significantly more dysfunction. CONCLUSIONS: After an initial period of mild to moderate urinary symptoms prostate brachytherapy is well tolerated with relatively little deterioration in long-term quality of life. Long-term reduction in sexual function may be seen particularly in those requiring hormones.  相似文献   
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