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    From epithelial dysplasia to squamous carcinoma of the head and neck region: evolutive and prognostic histopathological markers

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    Ki67 immunoreactivity, p53 expression and apoptotic index were examined in 26 non-malignant lesions of the head and neck region, 22 dysplastic lesions of patients without evidence of head and neck carcinoma during follow-up time, 24 dysplastic lesions of patients who subsequently developed a squamous carcinoma in the same area, and 42 squamous cancer cases. A directly proportional relation between Ki67 immunoreactive pattern, apoptotic index and histological evolution from normal to dysplastic or neoplastic mucosa was evident. As far as p53 protein is concerned, its expression became higher and frequently transmural in neoplastic mucosa. A strict correlation between frequency and density of Ki67/p53 immunoreactivity according to invasive cell grading (ICG) scores and poor prognosis of patients were found. On the contrary, malignant cells highly expressing p53 seemed not to undergo apoptosis. Ki67 antigen and p53 protein detection in premalignant lesions and in carcinomas of the head and neck tract could be a useful marker for the management of patients at risk

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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