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Impianto di condrociti autologhi su membrana (MACI®):tecnica di ingegneria tissutale nella riparazione delle lesioni cartilaginee
No full textObiettivi: Scopo dello studio è valutare l’efficacia del trattamento delle lesioni condrali, focali ed artrosiche iniziali, del ginocchio e della caviglia con condrociti autologhi impiantati su membrana biologica (MACI®).
Materiali e metodi: Per la riparazione di queste lesioni è stata utilizzata una tecnica di bioingegneria tissutale: condrociti autologhi, prelevati per via artroscopica dal ginocchio, sono stati coltivati in vitro per 4 settimane in siero autologo e seminati su una membrana di collagene tipo I/III la quale, in un secondo tempo artrotomico, è stata applicata nel difetto condrale utilizzando colla di fibrina.
La struttura della membrana ed il fenotipo condrocitario sono stati indagati utilizzando tecniche di microscopia (ottica e SEM) ed elettroforesi (SDS PAGE 7 %).
Con questa tecnica sono stati trattati, dal Dicembre 1999 al Maggio 2001, 18 pazienti (11 uomini, 7 donne) con età compresa tra i 17 ed i 52 anni. La misura media del difetto era 3.5 cm2 (min. 2, max 4.5). La localizzazione della lesione era la seguente: 9 condili femorali mediali, 2 condili femorali laterali, 1 troclea femorale, 1 rotula , 3 cupole astragaliche delle quali una associata a lesione della superficie tibiale, 2 piatti tibiali esterni dei quali uno associato a lesione rotulea.
I pazienti sono stati valutati sotto il profilo clinico-funzionale (scheda ICRS, Cincinnati modificata, Lysholm II, Tegner ed AOFAS) e morfologico (RMN a 6 e 12 mesi post-op).
Risultati: I dati forniti dalla microscopia ottica e dalla SEM hanno evidenziato condroblasti attivi nella produzione di fibrille collageniche. L’elettroforesi ha dimostrato la presenza di collagene tipo II all’interno della membrana.
Il follow-up medio dei pazienti al momento del presente studio è di 6.4 mesi. Otto pazienti presentano un follow-up superiore ai 6 mesi, quattro ad 1 anno. I risultati clinici, secondo le scale di valutazione utilizzate, risultano essere uniformemente buoni con un incremento dei punteggi rispetto al periodo antecedente la procedura.
La RMN ha evidenziato nei pazienti con un follow-up più lungo la presenza di tessuto cartilagineo simil-ialino nei difetti trattati.
Conclusioni: MACI® si presenta come una tecnica innovativa per il trattamento delle lesioni condrali in virtù della semplicità di esecuzione dell’atto chirurgico, con riduzione dei tempi operatori e maggiore versatilità d’impiego rispetto alle tecniche tradizionali.
I dati istologici e biochimici, così come i risultati clinico-funzionali e morfologici preliminari, dimostrano che MACI® è una tecnica promettente nel trattamento delle lesioni condrali
Six-year experience with the Delta III reverse shoulder prosthesis.
Full text linkTo report the clinical and radiographic results and complications of the Delta III reverse prosthesis.24 women and 2 men aged 62 to 84 (mean, 75) years underwent total shoulder replacement using the Delta III reverse prosthesis. Patient diagnoses were massive rotator cuff tear (n=20), disabling sequelae of proximal humeral fractures (n=3), and failure of an unconstrained arthroplasty (n=3). Clinical and functional results were assessed using the Constant scale. Active range of motion (ROM) was measured. Scapular notching and radiolucent lines around the humeral component were evaluated using radiographs. Patient satisfaction of the treatment was evaluated by a direct interview.23 patients were followed up for 26 to 84 (mean, 42) months. Two patients had loosening of the glenoid component (at 6 months and 5 years) and underwent revision surgery. There were no instances of infection, instability, or acromial fracture. Only active elevation improved significantly after surgery, as did both the absolute and adjusted Constant scores. 12 patients were completely pain-free, 9 complained of slight pain, and one of moderate pain. The severity of scapular notching progressed with time. 15 patients were satisfied with the treatment, 6 were partially satisfied, and 2 were not satisfied.The Delta III prosthesis restores shoulder function but has biomechanical limits. Its use should be limited to elderly patients with severe impairment of the glenohumeral joint. Scapular notching is a main concern for the long-term survival of the implant
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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