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Harbaum L, Pollheimer M J, Kornprat P, Lindtner R A, Schlemmer A, Rehak P & Langner C
(2011) Histopathology 59 , 225–234 Keratin 7 expression in colorectal cancer – freak of nature or significant finding? Aims: To assess the prevalence of keratin 7 (K7) expression in colorectal cancer and to correlate findings with clinicopathological parameters and patients' outcome. Method and results: A total of 370 patients were evaluated for K7 expression by immunohistochemistry using a tissue microarray technique. K7 expression was scored semiquantitatively as either focal (<10%), moderate (10–50%) or extensive (>50%). In all, 32 (9%) tumours were immunoreactive for K7, with five cases showing extensive, four moderate and 23 focal expression, respectively. K7 expression was associated with poor tumour differentiation (P = 0.005) and the extent of tumour budding (P = 0.02). In whole sections, K7 immunoreactivity prevailed in single cells and small clusters of cells at the invasion front. Analysis of serial sections showed that K7‐positive cells colocalized with keratin 20, whereas they lacked immunoreactivity for E‐cadherin, MUC2 and MIB‐1. Disease progression occurred in 52% of patients with K7‐positive tumours and 41% with K7‐negative tumours (P = 0.19); 48% of patients with K7‐positive tumours but only 33% with K7‐negative tumours died of disease (P = 0.06). Conclusions: Aberrant expression of K7 in budding cancer cells represents a modification of the epithelial phenotype (‘epithelial–epithelial transition’: EET) which may be linked to gains in motility and invasive potential.  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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A 56-year-old male with a history of cutaneous neuroendocrine (Merkel cell) carcinoma presented with a solid mass of the left kidney, measuring 10 cm in largest diameter. On histology, the tumour was composed of loosely packed uniform cells with round-to-oval nuclei and scant cytoplasm. Immunohistochemically, the tumour cells diffusely expressed pancytokeratin and neuroendocrine markers, such as chromogranin A, synaptophysin and CD56 (NCAM). Distinct paranuclear dot-like expression of cytokeratin 20 showed the lesion to be metastatic Merkel cell carcinoma. This is the first reported case of Merkel cell carcinoma metastatic to the kidney mimicking primary neuroendocrine renal cancer. We discuss the differential diagnosis of the tumour and perform a systematic literature review, including potential indications for renal tumour biopsy in patients with a history of nonrenal malignancy.  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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Background  

The Dutch Consumer Quality Index Hip Knee Questionnaire (CQI Hip Knee) was used to assess patients' experiences with and evaluations of quality of care after a total hip (THA) or total knee arthroplasty (TKA). The aim of this study is to evaluate the construct validity and internal consistency reliability of this new instrument and to assess its ability to measure differences in quality of care between hospitals.  相似文献   
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A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
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