1,720,959 research outputs found
Impact of Dermoscopy and Reflectance Confocal Microscopy on the Histopathologic Diagnosis of Lentigo Maligna/Lentigo Maligna Melanoma
Full text linkBACKGROUND: Equivocal pigmented lesions of the head are usually biopsied to avoid inappropriate treatment. Clinical approach has evolved from simple visual examination to sophisticated techniques for selecting the biopsy sites. OBJECTIVE: This study aimed to retrospectively evaluate the efficiency of dermoscopy (DE) and reflectance confocal microscopy (RCM) in sampling a histopathologically representative focus of lentigo maligna/lentigo maligna melanoma. METHODS: Punch biopsies and surgical excisions of 72 patients, 37 men and 35 women (median age 70.6 years, range 39-90 years), affected by lentigo maligna/lentigo maligna melanoma of the head, sent from a single dermatology clinic, were reviewed for the presence of 5 histopathologic criteria: atypical junctional melanocytes, increased junctional melanocytes, follicular colonization, pagetoid spread and melanocytic junctional nests, plus other minor features. Forty-two patients were biopsied under DE and 30 under RCM guidance. RESULTS: Accuracy of the 2 techniques in sampling a representative tissue overlapped in most cases, although RCM selected sites to biopsy with more histopathologic criteria, in particular pagetoid spread and melanocytic nests. Interestingly, with RCM, inflammation and melanophages were observed more in biopsy than in excision. False positive cases were not registered. CONCLUSION: Compared with the sampling at naked eye, our results show that DE and RCM help selecting the most appropriate areas for biopsies, thus allowing not only more robust histopathologic diagnoses, but also a more accurate microstaging of tumor
Exploring the mesenteric lymphatic apparatus: A morphological and immunohistochemical investigation with clinical correlations
No full textModern immunohistochemical techniques allow a detailed study of the lymphatic system in many organs and areas of the body. We performed an in-depth study on lymphatic vessels of the ileal and colonic mesenteries, together with the greater omentum where they appear particularly numerous and mainly represented by capillaries interconnected among themselves and with lymph nodes. The capillary wall consists of a fine single sheath of endothelial cells wrapped around by a subtle collagen membrane and deprived of valves. The progression of lymph flow is promoted by external forces acting on the capillary walls. Only at the mesenteric roots can pre- and post-lymph nodal collector vessels be observed. Our observations help to explain different patho-physiological correlations and the possible presence of skip lymph node metastases
Oral atrophic lichen planus and oral lichenoid lesion malignant transformation: report and management of two cases
No full textBACKGROUND: There is an ongoing debate in the literature whether patients with oral lichen planus (OLP) carry an increased risk of developing a squamous cell carcinomas. Nevertheless, there is a tendency to accept that there is. The annual malignant transformation rate amounting less than 0.5%. This chronic disorder mainly affects middle-aged people. The etiopathogenesis is still poorly understood. There is no effective treatment and there are no preventive measures either. An important obstacle in the discussion on the possible potentially malignant character of oral lichen planus is caused by the lack of clear clinical and histopathologic diag- nostic criteria of oral lichen planus, resulting in a poor clin- icopathologic correlation in the diagnosis. One of the major problems of interpretation of malignant potential studies of OLP is the inexistence of strict diagnostic criteria to differentiate lichenoid processes. Some studies have included cases of OLP with OLL and vice versa. The differentiation between OLP and OLL has become important, since the latter might have a greater malignant potential. For this reason, it is important to establish precise clinical and histopathological criteria of differentiation of the lesions.
CASE REPORT: 1st) A 73 years old woman with a 12 months histological diagnosis of oral lichen planus localized on tongue dorsum, previously biopsied and studied in a differ- ent structure, came to our attention to investigate an ulcerative lesion on tongue midline. No smoking habit, alcohol abuse, anemia or previous malignancies diagnosis were referred; topical corticosteroid therapy was referred.
An incisional biopsy was performed showing lichenoid lesion, atypia and high grade of dysplasia at histological examination. Subsequently, lesion was radically removed with wide excision margins. Microscopic examination returned diagnosis of mild differentiated squamous cell carcinoma arose on lichenoid lesion. Resection margins were clean without perineural or vascular invasion.
After 18 months follow-up, symptoms of dull pain and burn sensation were referred. Tongue dorsum was macroscopically altered, with an ulcer-like lesion surrounded by edematous mucosa. Consequently, an incisional biopsy was performed showing the presence of a low differentiated squamous cell carcinoma. Lesion was radically excised, margins were widened and examined with frozen sections. Patient underwent to bilateral SND (level I-III) and RTP.
Histological examination returns a diagnosis of recurrent pT1 pN1 micro-invasive squamous cell carcinoma. Microscopic signs of lichenoid lesion were still evident.
2nd) A 74 years old woman, with a 20 months history o
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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