1,720,953 research outputs found
Angiographical and clinical therapy control of treated ruptured and non-ruptured pericallosal aneurysm
No full textEinleitung: Die retrospektive Unicenter-Studie handelt von Therapiekontrollen endovaskulär oder operativ versorgter Aneurysmen der A. pericallosa. Die A. pericallosa ist die Endstromarterie der A. cerebri anterior und weist aufgrund ihrer distalen Lage sowie der Nähe zur Falx cerebri und der interhemisphärischen Fissur schwierige und räumlich begrenzte chirurgische Zugangswege auf. Sie ist mit einer Inzidenz von etwa 4,5% Lokalisation von Aneurysmen.
Intention der Arbeit ist der zunehmende Stellenwert endovaskulärer Intenvertionstechniken bei der Behandlung intrakranieller Aneurysmen. Zielsetzung dieser Arbeit ist es, durch retrospektive Analyse von Bild- und Patientendaten die klinischen und angiografischen Ergebnisse der endovaskulären und operativen Behandlungsmethode für Patienten mit einem Aneurysma der A. pericallosa am Universitätsklinikum Essen zu vergleichen. Ein weiterer Schwerpunkt dieser Studie liegt in der Ermittlung der Inzidenz von Aneurysmarezidiven in Bezug auf die beiden Behandlungsvarianten.
Außerdem sollen die endovaskulären bzw. chirurgischen Behandlungsergebnisse für Pericallosa-Aneurysmen am Universitätsklinikum Essen mit den Resultaten anderer Studienzentren verglichen werden.
Methode: Im Jahr 2013 und 2014 wurden die klinischen und angiografischen Daten von 101 Patienten, die wegen eines Pericallosa-Aneurysmas an der Universitätsklinik Essen behandelt wurden oder wegen möglicher Behandlungsindikation mit den Fachbereichen der Neuroradiologie und Neurochirurgie in Kontakt getreten sind, zusammengetragen. Der Beobachtungszeitraum erstreckte sich von August 1998 bis August 2013. Erfasst wurden dabei die Patienten, die aufgrund ihres Pericallosa-Aneurysmas gecoilt, geclippt oder gewrapped wurden. Außerdem fanden auch die Patienten Beachtung, die unbehandelt geblieben sind oder lediglich eine konsiliarische Mitbeurteilung von hiesigen Neuroradiologen erhalten haben. Als primäre Informationsquellen dienten dabei das Radiologie-Informations-System Centricity für die schriftlichen Befunde und das PACS- Programm für die Bildbefunde. Um Information zu den klinischen Ergebnissen und dem klinischen Verlauf der Patienten zu bekommen, wurden Arztbriefe und vorhandene Fragebögen zur Lebensqualität retrospektiv ausgewertet. Zusätzlich habe ich noch Datenmaterialien dem Zentralarchiv der Uni Essen und dem Archiv für Neurologie und Neurochirurgie entnommen. Um die Therapieerfolge und klinische Ergebnisse der gecoilten und geclippten Patienten statistisch direkt miteinander vergleichen zu können, wurde der Mann-Whitney- U Test durchgeführt.
Ergebnisse: Nach Auswertung der erhobenen Daten zeigte sich, dass die Pericallosa-Aneurysmen von 48 Patienten durch eine Coilembolisation behandelt worden sind, während 29 Patienten operativ neurochirurgisch versorgt und weitere 22 Patienten konservativ beobachten worden sind.
Am Universitätsklinikum Essen traten bei 6 von 75 behandelten Patienten Rezidive von A. pericallosa-Aneurysmen auf. Demnach wurde eine Rezidivrate von 8% innerhalb von fünfzehn Beobachtungjahren ermittelt. Alle Rezidive betrafen coilembolisierte Pericallosa-Aneurysmen. Es entwickelten sich Rezidive vor allem bei den Patienten, die ein breitbasiges Aneurysma aufwiesen und unregelmäßig konfiguriert waren. Insgesamt konnten drei Rezidiv-Aneurysmen durch ein erneutes Coiling erfolgreich behandelt werden. Weitere drei Pericallosa-Aneurysmen wurden mit einem Clip endgültig versorgt. Im internationalen Vergleich zeigt sich, dass in internationalen Studien die Rezidivrate von behandelten intrakraniellen Aneurysmen zwischen 13% und 34% im ersten Jahr nach Intervention deutlich höher liegt. Innerhalb der Studienpopulation gab es insgesamt 7 Todesfälle und damit eine Gesamtmortalitätsrate von 6,9%, welche deutlich unter der durchschnittlichen Sterberate von 11% in internationalen Studien liegt.
Hinsichtlich des klinischen Outcomes konnte am Universitätsklinikum Essen zwischen den gecoilten und geclippten Patienten kein signifikanter Unterschied bezüglich des Therapieerfolges (p=0,190) gefunden werden. Während sich allerdings ein geringeres Nebenwirkungsprofil bei den coilembolisierten Patienten zeigte.
Zusammenfassung/Schlussfolgerung: Die Schlussfolgerung dieser Ergebnisse ist, dass die Behandlung von Patienten mit einem Pericallosa-Aneurysma weiterhin einer individuellen und interdisziplinären Planung und Entscheidung bedarf. Generell wird empfohlen, dass jüngere Patienten mit einem kleinen Aneurysma (< 3 mm) und einer komplexen Morphologie des Aneurysmas und weitem Aneurysmahals ein besseres Resultat mittels Clipping erhalten.
Hingegen würden ältere Patienten mit Aneurysmen größer als 3 mm und einfachen Aneurysmakonfigurationen und engem Aneurysmahals mehr von einem endovaskulären Coiling profitieren.Objective: Pericallosal artery aneurysms are usually rare (~ 4,5%), and treatment is challenging for both surgical and endovascular modalities. This analysis was performed to determine the angiographical and clinical outcome.
Methods: A total of 101 patients with pericallosal artery aneurysm were admitted to our hospital between 1998 - 2013 and analyzed retrospectively. Outcome was measured based on the Glasgow Outcome Scale after intervention and 6 month later.
Results: 48 patients with pericallosal aneurysm were treated with endovascular coiling whereas 29 patients underwent surgical clipping and 22 patients were observed without any treatment. 6 aneurysms treated by coiling recanalized, with a recurrence rate of 8% at university hospital of Essen. All recanalized pericallosal aneurysm showed a wide neck and irregular configuration in DSA sequences. Concerning the clinical outcome there were no statistically significances between the recanalization and surgery groups (p=0,190).
Conclusions: In conclusion it is still an individual and interdisciplinary decision to treat a pericallosal artery aneurysm
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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