1,720,958 research outputs found
Five years of experience using a dermal substitute: indications, histologic studies, and first results using a new single-layer tool.
No full textBACKGROUND: Dermal substitutes have been used in Europe since 1996 as a mean of reconstructing the dermal layer.
OBJECTIVES: To introduce the dermal substitute as a dual-stage reconstructing procedure using the dual-layer version and as a single-stage procedure, combining the single layer with a skin graft to achieve immediate closure. Our further objective was to evaluate the persistence of a commercial dermal substitute in the host's dermal layer using serial histologic studies.
MATERIALS AND METHODS: The dermal substitute used was a membrane made using a porous coprecipitate of type I bovine collagen and glycosaminoglycan organized in a three-dimensional structure that allows the host's cell to migrate into it. It is available in a double-layer structure, covered by a silicone sheet, and in a single-layer structure without silicon.
RESULTS AND CONCLUSION: We describe the dermal substitute indications in dermatologic surgery and our first results with the single layer as a single-stage procedure with an 80% to 100% take rate. Our histological studies of both products show their perfect integration and the persistence of the peculiar three-dimensional structure (neodermis) 5 years from implantation of the dual-layer dermal substitute
Compared to coverage by STSG grafts only reconstruction by the dermal substitute Integra® plus STSG increases TcPO2 values in diabetic feet at 3 and 6 months after reconstruction
No full textAIM: Purpose of this retrospective comparative study is to evaluate the results of reconstruction of diabetic feet by split thickness skin graft (STSG) and by dermal substitute Integra® covered by STSG in terms of vascularity of the reconstructed wound-bed by measurements of tissue oxygenation (TcPO2).
PATIENTS AND METHODS: 23 patients were included into the study (12 were reconstructed by STSG only and 11 with Integra® and STSG three weeks later). In each patient TcPO2 measurements were performed at the same spot of the reconstructed area at 14 days, one month, 3 months, 6 months, 12 months and 24 months after reconstruction.
RESULTS: Wound beds reconstructed by Integra® showed on average 10 mmHg higher TcPO2.
CONCLUSIONS: Our study estimated in an objective way, by TcPO2 value measurements, the oxygenation of the wound bed in diabetic feet after reconstruction by STSG only and after adding dermal substitute Integra® to the wound bed before final STSG coverage. During first month after reconstruction no statistically significant differences were found. After 3 months TcPO2 studies revealed statistically significant higher oxygen tissue pressure in diabetic feet covered by Integra® plus STSG. These findings endorse in an objective way the clinical findings already reported while using the dermal substitute. It remains to explain the role of this increase of oxygen tissue pressure in redefine the indications for the use of dermal substitutes in reconstruction of poor vascularized regions
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
- …
