1,720,968 research outputs found
Treatment of chronic osteomyelitis with antibiotic-loaded bone void filler systems: an experience with hydroxyapatites calcium-sulfate biomaterials
No full textThis is a retrospective study that aims to quantify the problem of chronic osteomyelitis in one of the largest Italian orthopedic centers. Furthermore this study is focused on evaluation of efficacy of bone void filler systems with particular attention to a subgroup of patients treated with PerOssal®. Ninety-seven patients were included in this study between 2008 and 2013 with a minimum follow up of 24 months. A subgroup of 52 patients was treated with curettage plus PerOssal®, another group was treated with curettage only or curettage with other bone void filler systems.
Overall we obtained a cure rate of 80,4%, whereas 19,6% had recurrent infection. Looking at the subgroup treated with PerOssal® we found a healing rate of 86,5%, which was significantly higher compared to the other groups. Of the patients with recurrence of infection, those treated with PerOssal® recurred 106 days later than the other patients
A classification method for neurogenic heterotopic ossification of the hip.
Full text linkBackground: Existing classifications for heterotopic ossification (HO) do not include all HO types; nor do they consider the anatomy of the involved joint or the neurological injury. Therefore, we performed this study to propose and evaluate a classification according to the location of neurogenic HO and the neurological injury. Materials and methods: We studied the files of 24 patients/33 hips with brain or spinal cord injury and neurogenic HO of the hip treated with excision, indomethacin, and radiation therapy. We classified patients according to the Brooker classification scheme as well as ours. Four types of neurogenic HO were distinguished according to the anatomical location of HO: type 1, anterior; type 2, posterior; type 3, anteromedial; type 4, circumferential. Subtypes of each type were added based on the neurological injury: a, spinal cord; b, brain injury. Mean follow-up was 2.5 years (1-8 years). Results: The Brooker classification scheme was misleading - all hips were class III or IV, corresponding to ankylosis, even though only 14 hips had ankylosis. On the other hand, our classification was straightforward and easy to assign in all cases. It corresponded better to the location of the heterotopic bone, and allowed for preoperative planning of the appropriate surgical approach and evaluation of the prognosis; recurrence of neurogenic HO was significantly higher in patients with brain injury (subtype b), while blood loss was higher for patients with anteromedial (type 3) and circumferential (type 4) neurogenic HO. Conclusions: Our proposed classification may improve the management and evaluation of the prognosis for patients with neurogenic HO
Chondrosarcomas revisited.
No full textChondrosarcomas are malignant bone tumors with pure hyaline cartilage differentiation; myxoid changes, calcification, or ossification may be present. Several subtypes of chondrosarcomas exist. Behavior patterns vary, ranging from slow-growing nonmetastasizing lesions to aggressive metastasizing sarcomas. Symptoms are usually mild, with duration ranging from several months to years, and usually consist of persistent, dull, aching pain or palpable masses. Radiographic findings include bone expansion with cortical thickening, radiolucent areas with variably distributed punctate or ring-like matrix calcifications, cortical erosion or destruction, endosteal scalloping, and scant or absent periosteal reaction; extension into the soft tissue may be present. Histological differential diagnosis from benign cartilaginous lesions can be achieved by increased cellularity, enlarged plump nuclei, binucleated cells, hyperchromatic nuclear pleomorphism, and permeation of cortical or medullary bone. Atypia is usually mild to moderate; necrosis and mitoses can be seen, particularly in high-grade lesions. Adequate surgery is the mainstay of treatment. High-grade and pelvic chondrosarcomas are best managed with wide resection. Because of the low metastatic potential and low local recurrence rate noted with intralesional surgery, low-grade chondrosarcomas can be treated with curettage (with or without treatment of the defect cavity) with a local adjuvant, such as phenol or cryotherapy. Adjuvant chemotherapy may be considered for mesenchymal and dedifferentiated chondrosarcomas. Radiation therapy can be considered after incomplete resection or if resection is not feasible or would cause unacceptable morbidity
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
Synovial sarcoma: Retrospective analysis of 250 patients treated at a single institution
No full textBACKGROUND: The optimal treatment for synovial sarcoma remains controversial. Treatment, outcome, and prognostic factors in patients treated in a single institution were examined. METHODS: Synovial sarcoma patients who underwent surgery at the Rizzoli Institute between 1976 and 2006 were identified and analyzed. RESULTS: Characteristics of the 250 patients (128 female; 122 male) included: median age, 37 years (range, 7-83 years); 177 (71%) with tumors in the lower extremity, 40 (16%) with tumors in the upper extremity, and 33 with tumors in the trunk (13%); primary lesion size >5 cm in 121 patients (55%); and 204 (82%) patients with localized disease and 46 (18%) with metastatic disease at the time of presentation. All patients with localized disease underwent surgery. Twenty-four percent of patients underwent amputation. Adequate surgical margins were achieved in 88% patients. In patients with localized disease, radiotherapy was administered to 103 (50%) patients, and chemotherapy to 98 (48%). With a median follow-up of 5.5 years (range, 1-30 years), the 5-year overall survival rate was 10% for patients with metastatic disease and 76% for patients with localized disease (P = .0001). The 5-year event-free survival was 58% in patients with localized disease. Multivariate analysis indicated that size, age, histologic subtype, and the use of radiotherapy were independent factors for event-free survival. CONCLUSIONS: In those patients with localized disease, a good rate of cure can be achieved. Age, size, histology, and use of radiotherapy influence prognosis, whereas to the authors' knowledge, the role of adjuvant chemotherapy remains unproven. © 2009 American Cancer Society
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
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