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INTERSTITIAL PNEUMONITIS IN ACUTE LEUKEMIA PATIENT SUBMITTTED TO T-DEPLETED METCHED AND MISMATCHED BONE MARROW TRANSPLANTATION
No full textTau protein in cerebrospinal fluid: a new diagnostic and prognostic marker in Alzheimer disease?
No full textTau is the main protein of paired helical filaments. It can be detected and measured in cerebrospinal fluid (CSF) and for this reason it has been proposed as a possible in vivo marker of Alzheimer disease (AD). To evaluate the usefulness of CSF tau in the diagnosis of AD we measured it in patients with AD, frontal lobe dementia (FLD), vascular dementia (VD), and in healthy controls by means of a specific enzyme-linked immunosorbent assay test. Individuals with AD had significantly higher tau levels than FLD, VD, and controls. Individuals with late onset AD had significantly higher levels than those with early onset disease. In AD, CSF tau level did not correlate with age, duration, or severity of the disease, whereas a correlation with age was found in FLD and controls. In the nine AD patients in whom CSF tau measurement was repeated after 2 years, mean levels did not differ from baseline, although a worsening of cognitive performances occurred. The overlap among the different groups and the absence of any modification over time suggest that CSF tau measurement, more than in confirming or staging overt AD, might be useful in revealing the disease at its preclinical phase
Oxidative stress and lymphocytes in Alzheimer disease
No full textOxidative stress has been involved in the pahtogenesis of different neurodegenerative diseases. Recently high levels of 8-hydroxy-2’-deoxyguanosine [I)-OHdC), a sensitive marker of DNA damage, were found in both nuclear and mitochondrial DNA of the brain in Alzheimer disease (AD). In this study we measured 8-OHdG in lymphocyte DNA obtained from AD patients and from age- matched controls. The high levels of 8-OHdG found in the lymphocytes of AD patients support the hypothesis that a general imbalance is present in this disease between oxidants and antioxidants
Autoantibodies against oxidized low-density lipoproteins in older stroke patients. (Letter)
No full textGoing 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
Oxidative damage to lymphocyte DNA from AD patients
No full textOBJECTIVE: Several studies show structural and functional alterations in peripheral cells in AD. The purpose of this study was to evaluate oxidative stress in AD lymphocytes.
BACKGROUND: The literature supports the role of reactive oxygen species in the pathogenesis of AD because several markers of oxidative damage have been detected in AD brain.
METHODS: 8-hydroxy-2'-deoxyguanosine (8OHdG), a marker of oxidative stress in DNA, was measured in lymphocytes of AD patients and healthy aged controls with high-pressure liquid chromatography with electrochemical detection, both at basal condition and after acute oxidative stress with hydrogen peroxide.
RESULTS: A significantly higher concentration of 8OHdG in lymphocytes occurred in AD patients compared with controls. In this latter group, 8OHdG increased progressively with age. After acute oxidative stress, levels of formed 8OHdG did not differ between AD patients and controls.
CONCLUSIONS: Our results support that AD is affected by oxidative stress, detectable not only in the brain but also in peripheral cells; oxidative mechanisms may contribute to the pathogenesis of AD. Additional studies in other neurodegenerative diseases are needed to evaluate these findings
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
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