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Elinikäisen alkoholialtistuksen vaikutus rotan isoaivokuoren IV-solukerroksen hermosoluihin kertyvään lipotuskiinin määrään ja esiintymiseen soluissa.
No full textSyventävä työ ei kirjastoss
Ultraäänihoidon vaikutus liukenevalla luunkiinnittimellä kiinnitetyn hohkaluun murtuman paranemiseen
No full textThe purpose of the present study was to investigate the effects of low-intensity ultrasound on bioabsorbable self-reinforced poly-L-lactide (SR-PLLA) screws and on fracture healing after SR-PLLA device fixation in experimental and clinical cancellous bone fracture. In the first experimental study, the assessment of the mechanical strengths of the SR-PLLA screws was performed after 12 weeks of daily 20-minute ultrasound exposure in vitro. In the second experimental study, 32 male Wistar rats with an experimental distal femur osteotomy fixed with an SR-PLLA rod were exposed for daily low-intensity ultrasound treatment for 21 days. The effects on the healing bone were assessed.
The clinical studies consist of three prospective, randomized, and placebo-controlled series of dislocated lateral malleolar fractures fixed with one SR-PLLA screw. The total number of the patients in these series was 52. Half of the patients were provided randomly with a sham ultrasound device. The patients underwent ultrasound therapy 20 minutes daily for six weeks. Radiological bone healing was assessed both by radiographs at two, six, nine, and 12 weeks and by multidetector computed tomography (MDCT) scans at two weeks, nine weeks, and 18 months. Bone mineral density was assessed by dual-energy X-ray absorptiometry (DXA). The clinical outcome was assessed by both Olerud-Molander scoring and clinical examination of the ankle.
Low-intensity ultrasound had no effects on the mechanical properties and degradation behaviour of the SR-PLLA screws in vitro. There were no obvious signs of low-intensity ultrasound-induced enhancement in the bone healing in SR-PLLA-rod-fixed metaphyseal distal femur osteotomy in rats. The biocompatibility of low-intensity ultrasound treatment and SR-PLLA was found to be good. In the clinical series low-intensity ultrasound was observed to have no obvious effects on the bone mineral density of the fractured lateral malleolus. There were no obvious differences in the radiological bone healing times of the SR-PLLA-screw-fixed lateral malleolar fractures after low-intensity ultrasound treatment. Low-intensity ultrasound did not have any effects on radiological bone morphology, bone mineral density or clinical outcome 18 months after the injury.
There were no obvious findings in the present study to support the hypothesis that low-intensity pulsed ultrasound enhances bone healing in SR-PLLA-rod-fixed experimental metaphyseal distal femur osteotomy in rats or in clinical SR-PLLA-screw-fixed lateral malleolar fractures. It is important to limit the conclusions of the present set of studies only to lateral malleolar fractures fixed with an SR-PLLA screw.Tutkimuksessa selvitettiin matala-intensiteettisen ultraäänihoidon vaikutusta liukenevalla luunkiinnittimellä kiinnitetyn hohkaluun murtuman paranemiseen. Tutkimus koostui viidestä osatyöstä, joista kaksi ensimmäistä oli kokeellisia ja seuraavat kolme kliinisiä.
Liukenevista materiaaleista valmistettuja luunkiinnittimiä käytetään erilaisten murtumien kiinnittämiseen. Tässä tutkimuksessa käytetyt sauvat ja ruuvit olivat valmistettu elimistössä liukenevasta polylaktidista. 20 minuuttia kestävän päivittäisen matala-intensiteettisen ultraäänihoidon on eräissä tutkimuksissa esitetty nopeuttavan luunmurtuman paranemista. Tämän tutkimuksen tarkoituksena oli selvittää ultraäänihoidon yhteensopivuus liukenevien luunkiinnittimien kanssa sekä ultraäänihoidon vaikutukset hohkaluun murtuman paranemiseen.
Ensimmäisessä kokeellisessa työssä polylaktidi-ruuveja altistettiin päivittäiselle ultraäänelle 12 viikon ajan. Ultraäänen ei todettu vaikuttavan heikentävästi polylaktidin mekaanisiin ominaisuuksiin. Toisessa kokeellisessa työssä kiinnitettiin 32 rotan katkaistu reisiluun alaosa polylaktidi-sauvalla ja tälle alueelle annettiin päivittäin ultraäänihoitoa kolmen viikon ajan. Ultraäänen ei todettu selvästi vaikuttavan paranevassa luussa tapahtuviin normaaleihin muutoksiin. Kliinisissä töissä paikaltaan siirtynyt nilkan ulkokehräksen murtuma kiinnitettiin operatiivisesti polylaktidi-ruuvilla ja murtumaa hoidettiin leikkauksen jälkeen kuuden viikon ajan päivittäin ultraäänellä. Ensimmäisessä kliinisessä työssä selvitettiin ultraäänihoidon vaikutusta ulkokehräksen luuntiheyteen 12 viikon kohdalla leikkauksesta 30 potilaalla. Ultraäänellä ei todettu olevan vaikutusta vamman ja leikkauksen jälkeiseen luuntiheyden muutokseen. Toisessa kliinisessä työssä selvitettiin ultraäänihoidon vaikutusta ulkokehräksen murtuman radiologiseen luutumiseen 22 potilaalla yhdeksän viikon kohdalla tehdyllä tietokonekuvauksella. Ultraäänihoidolla ei todettu olevan selvää radiologista luutumista nopeuttavaa vaikutusta. Viimeisessä kliinisessä työssä tutkittiin ultraäänihoidon mahdollisia pitkäaikaisvaikutuksia leikatussa nilkassa puolitoista vuotta vamman jälkeen 16 potilaan aineistossa. Kaikki murtumat olivat parantuneet hyvin, ultraäänihoidolla ei todettu olevan vaikutusta kliiniseen tulokseen tai luuntiheyden muutokseen leikatussa nilkassa.
Tässä väitöskirjatutkimuksessa todettiin matala-intensiteettisen ultraäänihoidon soveltuvan käytettäväksi liukenevilla luunkiinnittimillä kiinnitetyissä murtumissa. Toisaalta, poiketen aikaisemmin julkaistuista tuloksista, ultraäänihoidolla ei tässä tutkimuksessa todettu olevan selviä hohkaluun murtuman paranemista edistäviä vaikutuksia.ei saavutettav
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Traumapotilaan ilmatien ja hengityksen turvaamiseksi tehtävät kirurgiset hätätoimenpiteet
No full textVariations on the Author
No full text“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
No full textWe 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
No full textWe 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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