1,720,975 research outputs found
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
Interferon-β therapy and risk of thrombocytopenia in multiple sclerosis patients
Full text linkThrombocytopenia is a well-described adverse event of several disease-modifying therapies (DMT) in multiple sclerosis (MS). On the other hand, an increased prevalence of MS has been reported in patients with immune thrombocytopenia. In this retrospective, cross-sectional, case–control study we evaluated in a heterogeneous MS cohort: (1) the prevalence of thrombocytopenia in comparison with sex- and age-matched controls; (2) the relationship between thrombocytopenia and patients’ demographic, clinical characteristics; (3) the risk for thrombocytopenia in relation to DMT. 187 consecutive MS patients [51 males, mean age (±SD) 44.5 ± 10.7 years] and 200 controls (56 males, mean age 45.5 ± 12 years) were included. Thrombocytopenia was defined as platelet count lower than normal laboratory values (130–400 × 109/L). The prevalence of thrombocytopenia was significantly higher in MS patients than in controls (7 vs. 2.5 %, p = 0.04). Thrombocytopenia was present only in relapsing–remitting MS cases, and significantly associated with lower EDSS (p = 0.002) and with a trend for shorter disease duration (p = 0.06). It was more frequent in patients on high-dose interferon-β therapy compared with those on low-dose interferon-β therapy, other therapies or untreated patients (p = 0.02). High-dose interferon-β therapy was associated with more than eightfold increase in the risk for thrombocytopenia (odds ratio 8.60, 95 % confidence interval: 1.01–74.48 adjusted for EDSS, disease duration and type of disease). The prevalence of thrombocytopenia was increased in MS patients treated with DMT. High-dose interferon-β therapy is the variable most strongly associated with thrombocytopenia
Anti-annexin antibodies, cholesterol levels and disability in multiple sclerosis
No full textSo far, no studies have been conducted to evaluate possible correlations between lipid/lipoprotein levels and the anti-phospholipid antibody (aPL) positivity in multiple sclerosis (MS). In this cross-sectional study, we aimed to investigate the relationships between serum lipid profile and aPL positivity rates in MS patients, and their possible differences among secondary-progressive MS (SPMS) patients, relapsing–remitting MS patients in remission (REM) and in relapse (REL). We included 16 SPMS, 58 REM and 26 REL. Their sera were tested for aPL (anti-cardiolipin, anti-β2glycoproteinI, anti-prothrombin, anti-annexinV), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and lipoprotein(a) levels. High TC levels were more frequent in SPMS patients than other groups (p = 0.05). The REL had significantly higher rates of positivity for anti-β2glycoproteinI IgM (p < 0.0001), anti-prothrombin IgG and IgM (both p = 0.05) than the other groups. A significant positive correlation was found between age and both TC and LDL-C, disability and both TC and LDL-C, disease duration and LDL-C. TC levels were significantly higher (p = 0.007) in anti-annexinV-IgG positive patients. The anti-annexinV-IgG positivity significantly associated with high levels of TC (p = 0.002) and LDL-C (p = 0.03). Our results support the hypothesis that both thrombogenic and neurodegenerative mechanisms associated with an abnormal cholesterol homeostasis might contribute to MS progression. Our study may have interesting practical implications, which could potentially open new therapeutic approaches in the context of appropriately designed clinical trials
Association between Anemia and Multiple Sclerosis
No full textBACKGROUND/AIMS:
The relationship between multiple sclerosis (MS) and anemia has not been clarified sufficiently. In this retrospective, cross-sectional, case-control study we evaluated in MS patients: (1) prevalence of anemia relative to sex- and age-matched controls; (2) relationships between patients' demographic, clinical and drug-related characteristics and anemia; (3) effect of anemia on the risk of developing MS.
METHODS:
187 consecutive MS patients (51 males, mean age (±SD) 44.5 ± 10.7 years) and 200 controls (56 males, mean age 45.5 ± 12 years) were included in the study. Anemia was defined as hemoglobin <12 g/dl for females and <13 g/dl for males.
RESULTS:
There was a significant difference in the prevalence of anemia between MS patients and controls (35 (18.7%) and 19 (9.5%), respectively, p = 0.009). We did not find any association between patients' characteristics and anemia. The occurrence of anemia increased more than twice the risk of developing MS (odds ratio: 2.19, 95% confidence interval 1.19-4.0).
CONCLUSION:
Our study showed a consistent association between anemia and MS
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
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