1,720,959 research outputs found
Is video-assisted thoracic surgery justified at first spontaneous pneumothorax?
No full textOBJECTIVE:
The fundamental role of video-assisted thoracic surgery (VATS) in the treatment of spontaneous pneumothorax is generally acknowledged today. This study intends to evaluate whether VATS is justified at the onset of a first spontaneous pneumothorax through analysis of parameters tested on two group of patients treated respectively with pleural drainage and VATS.
PATIENTS/METHODS:
The study includes 70 patients affected by first spontaneous pneumothorax divided into two groups of 35 patients for the purpose of therapeutic treatment. The first group underwent pleural drainage while the second underwent VATS. Parameters analyzed were as follows: (1) prolonged air leaks (more than 6 days); (2) time required for pleural drainage; (3) time of hospital stay; (4) management costs; (5) recurrences (follow-up at 12 months).
RESULTS:
Prolonged air leaks occurred in four patients (11.4%) in the first group and two patients (5.7%) in the second; recurrences occurred in eight patients in the first group (22.8%), and only one in the second group (2.8%). Mean time for drainage and hospitalization was, respectively, 9 and 12 days in patients with pleural drainage against 3.9 and 6 days of those using VATS. Average management costs per patients including hospitalization was calculated at 1,925.00 for the second group.
CONCLUSIONS:
The use of VATS at first spontaneous pneumothorax is justified in the interest of both patients and health administrations as demonstrated by the number of recurrences in patients in the first group and economy savings resulting from use of VATS
Diagnostic and therapeutic approaches for masses in the posterior mediastinum
No full textBetween January 1980 and December 1997 twenty-one patients with a mass in the posterior mediastinum came under our observation. All of the patients underwent chest radiography, bronchoscopy, respiratory function tests, perfusional and ventilatory radionuclide scans, a computed tomography (CT) of the chest and blood gas analysis. In cases involving neurogenic tumours magnetic resonance imaging (MRI) was used. Ten patients underwent CT guided transthoracic needle biopsy. The excision was performed by means of a thoracotomy in 12 cases (57.1%) and by video assisted thoracoscopy surgery (VATS) in the other 9 (42.9%); no deaths were recorded. Eleven neurilemmomas, two bronchogenic cysts, two paragangliomas, two neuroepitheliomas, one neurogenic sarcoma and three esophageal duplications were found. The authors believe an accurate pre-operative assessment of the lesion can be obtained using CT and MRI. The video assisted thoracoscopy (VAT) is a useful method of diagnosis and treatment as it can be converted into VATS if the lesion is benign or cystic. Thoracotomy is necessary when the mass is malignant or when there is adhesion to or invasion of surrounding tissues
Video assisted thoracoscopy in thoracic injury: early or delayed indication ?
No full textThe aim of this study was to evaluate the diagnostic role and therapeutic effectiveness of videothoracoscopy in chest trauma. Between 1st January 1993 and 30th September 2003, 112 traumatized patients underwent a videothoracoscopy. The origin of trauma was different: 60 road accidents, 42 accidental falls, 7 knife wounds and 3 firearm wounds. Seventy-six patients presented hemothorax, 21 hemopneumothorax, 10 suspected diaphragmatic injury and 5 pericardium effusion. All patients were hemodynamically stable and conscious. In suspected diaphragmatic rupture patients, videothoracoscopy confirmed the presence of 4 lesions with diameter from 7 to 10cm. The etiopathogenetic causes in the other clinical patterns were: 20 lung lacerations, 17 apical adhesion lacerations, 11 diaphragmatic lesions, 16 wall bleedings and 38 vessel lesions. Ninety patients (80.3%) were treated with video assisted thoracic surgery. The remaining procedures were : 17 drainage tube insertions, 4 thoracotomies and 1 laparotomy. Videothoracoscopy made the use of the primary intention drainage tube obsolete in stable traumatized patients with hemothorax or hemopneumothorax. It is a safe technique that allows the diagnostic and surgical management of the lesions
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
- …
