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    Aneurismi infiammatori dell'aorta addominale

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    The authors present a review of the literature on inflammatory abdominal aortic aneurysms. These aneurysms represent from 3 to 10% of all abdominal aortic aneurysms. Progress has occurred in the technical approach to these aneurysms, and operative morbidity and mortality have been remarkably reduced. However, the pathogenesis remains poorly understood. Early reports have considered the inflammatory aneurysm as a distinct clinical and pathological entity, whereas recent evidences suggest a common etiopathogenetic mechanism for both atherosclerotic and inflammatory aneurysms. Finally, genetic and environmental factors, such as tobacco use, may predispose certain persons to the development of non-inflammatory aneurysms and others to a wide spectrum of inflammatory reactions until inflammatory aneurysms development. The most common clinical features of these aneurysms are represented by symptoms, such as abdominal or back pain, obstructive uropathy and by an elevated erythrocyte sedimentation rate. Computed tomography (CT) allows a specific diagnosis by the typical image of soft tissue surrounding the aortic wall enhancing with contrast administration. Ultrasonography is less sensitive whereas nuclear magnetic resonance (RNM) is a promising technique. Excretory urography may suggest the diagnosis by demonstration of ureter entrapment. Surgical therapy, by a technique of limited dissection represents the definitive treatment. Evolution of fibrosis after surgery is still debated because some studies have reported complete regression of inflammation and other partial regression or persistence of fibrotic process. At present, endovascular treatment of these aneurysms is occasionally reported, although preliminary results appear satisfactory

    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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