1,720,962 research outputs found
Investigation of the effects of lithium after long-term spinal cord damage
No full textOmurilik hasarı, sinir ağlarında meydana gelen nörolojik hasara ve fonksiyonel kayıpların oluşmasına neden olmaktadır. Hasara yönelik tedavi yöntemleri hasarın neden olduğu dejeneratif etkileri azaltmada yetersizdir. Omurilik hasarı sonrası rejenerasyon ve nöroproteksiyon hedefli etkili çalışmalar günümüzde yeterli derecede değildir. Bu nedenle etkili ve yeni terapötik odaklı çalışmaların yapılması gerekmektedir. Bipolar bozukluk için terapötik etki gösteren lityumun nörodejeneratif rahatsızlıkların tedavisinde protektif etki gösterdiği bilinmesine rağmen lityumun omurilik hasarı sonrası uzun dönemdeki iyileşmeye yönelik etkisi tam olarak bilinmemektedir. Bu bilinmezlikten yola çıkılarak bu tezde omurilik yarı kesi hasar modeli oluşturulan farelerde hasar sonrası farklı dozlarda uygulanan lityumun doza bağlı fonksiyonel geri kazanım açısından etkisi incelenmiştir. Terapötik lityum konsantrasyonunun hasar sonrası doku atrofisine, nöronal sağkalıma, glial hücreler üzerindeki etkisine ve aksonal plastisiteye yönelik etkileri incelenmiştir. Elde edilen sonuçlara göre foksiyonel gezi kazanım açısından 0.2 mmol/kg lityum uygulanmasının, hasardan 28 gün sonra sağ taraflı hemiplejik farelerin az olan lokomotor aktivitelerinde iyileşme sağladığı gözlenmiştir. Elektromiyografi yöntemi sonuçlarında, hasar sonrası uygulanan lityumun hemiplejik taraftaki gastrokinemius kası üzerinde uyarım sonrası sinyal iletimine ve kontraksiyona yönelik terapötik etki gösterdiği gözlenmiştir. Ayrıca lityum hasar alanındaki lezyon hacmini azaltıcı etki göstermiştir. 0.2 mmol/kg dozundaki lityum omuriliğin rostral segmentindeki atrofiyi azaltmış ve nöronlar üzerinde protektif etki göstermiştir. Lityum uygulaması glial hücre sayısını azaltıcı etki göstermekle birlikte, hasar sonrası dejenere olan aksonal yolakların rejenerasyonunu destekleyici etki göstermiştir. Sonuçlara göre, lityum tedavisinin omurilik hasarının dejeneratif etkilerine karşılık yeni ve etkili terapötik bir katkı sağlaması beklenilmektedir.Spinal cord injury causes neurological damage and functional loss in neural networks. Damage-oriented treatment methods are insufficient to reduce the degenerative effects. Effective studies targeting regeneration and neuroprotection after spinal cord injury are not sufficient today. Therefore, it is necessary to carry out effective and new therapeutic-oriented studies. Although it is known that lithium, is used for treatment of disorder, and has a protective effect in the treatment of neurodegenerative disorders, the effect of lithium on long-term recovery after spinal cord injury is not fully known. Based on this uncertainty, in this thesis, the effect of lithium administered at different doses in mice with a spinal cord half-incision injury model in terms of dose-dependent functional recovery was investigated. The effects of therapeutic lithium concentration on tissue atrophy, neuronal survival, effect on glial cells, and axonal plasticity after injury were investigated. It was observed that 0.2 mmol/kg lithium administration after injury improved the locomotor activities, which were less in right-sided hemiplegic mice 28 days after injury, in terms of functional excursion gain. According to the electromyography, lithium administration after injury, has a therapeutic effect on post-stimulation signal transmission and contraction on the gastrocnemius muscle on the hemiplegic side. As a result of the studies, lithium shows the effect of reducing the lesion volume in the damaged area. Lithium at a dose of 0.2 mmol/kg showed a reducing effect on atrophy due to damage in the rostral segment of the spinal cord and showed a protective effect on neurons. Lithium administration showed a decreasing effect on the number of glial cells, but it also showed a supportive effect on the regeneration of degenerated axonal pathways after damage. According to the results, it is expected that lithium treatment in the chronic period will provide a new and effective therapeutic contribution to the degenerative effects of spinal cord injury
Effects of repetitive transcranial magnetic stimulation (rtms) on post-brain stroke damage
No full textRepetatif transkraniyal manyetik stimülasyon (rTMS) tedavisi invazif olmayan, frekansı uyarıcı veya inhibe edici olmak üzere ayarlanabilen, beyin felci sonrası hemisferler arası düzeni tekrar sağlayan tedavi yöntemidir. Her ne kadar rTMS tedavisi klinikte sıklıkla kullanılsa da rTMS uygulamasının etki ettiği moleküler mekanizma tam olarak bilinememektedir. Beyin felci gelişmekte olan ülkelerde 2. ölüm sebebidir. rTMS tedavisinin, beyin felci sonrası moleküler mekanizmalardaki etkilerini araştırmak için 90 dakika orta serebral arter tıkanması modeli BALB/c farelerde oluşturuldu. Reperfüzyon başlangıcında uygulanan rTMS tedavisinin serebral kanlanma, hasar hacmi, ve gen ekspresyon değişiklikleri üzerindeki etkileri incelendi. Deney gruplarına 1 Hz inhibe edici, 20 Hz uyarıcı etki gösteren rTMS tedavisi uygulandı. Kontrol grubu rTMS tedavisi almadı. 20 Hz rTMS tedavisi kontrol grubuna ve 1 Hz grubuna göre iskemik kor bölgesinde, penumbra alanında ve hasarsız kortekste serebral kanlanmayı istatistiksel olarak anlamlı bir şekilde artırdı ve hasar hacmini istatistiksel olarak anlamlı bir şekilde azalttı. 20 Hz rTMS tedavisinin gen ekspresyonunda yaptığı değişiklikler enflamasyonun azaltılmasına, nöroplastisiteye ve vasküler regülasyona katkı sağladığı görüldü. Uygulanan 20 Hz rTMS tedavisinin beyin felci sonrası sonrası gen ekspresyonunu regüle ederek ve serebral kanlanmayı arttırarak hasarı azalttığı düşünülmektedir.Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive treatment method whose frequency is regulated as stimulator or inhibitor, which provides the balance between hemispheres after brain stroke. Although rTMS treatment is often used in clinic, effect of TMS on the molecular mechanism is unknown. Brain stroke is the second cause of death in the developing countries. A 90-minute of middle cerebral artery occlusion was induced in BALB/c mice to investigate the effects of rTMS treatment on molecular mechanism post-stroke. The rTMS treatment was administered at the beginning of reperfusion and the effects of treatment on infarct volume, cerebral blood flow and gene expression changes were examined. Experimental groups were designed as 1 Hz rTMS (inhibitory) application group, 20 Hz rTMS (stimulatory) application group whereas the rTMS treatment was not applied to the control group. 20 Hz rTMS treatment increased the cerebral blood flow in the ischemic core area, penumbra area and undamaged cortex when compared with control group. Also, 20 Hz rTMS treatment reduced the infarct volume. 20 Hz rTMS treatment regulated gene expression that contributes the reduction of inflammation, induction of the neuroplasticity related genes and the vascular regulation. It is believed that by regulating gene expression and increased cerebral blood flow the application of 20 Hz treatment decreased infarct volume
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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