1,720,959 research outputs found
Expression of pro-opiomelanocortin gene in human ovarian tissue
No full textThe high concentration of pro-opiomelanocortin (POMC)-derived peptides in human follicular fluid, which is several times higher than in plasma, suggested a local expression of the POMC gene. This has previously been observed in the animal ovaries. Peripheral POMC-like mRNAs are not translated in POMC-derived peptides but recent evidence supports the presence of a small amount of full-length transcript in human testes and lymphocytes. The purpose of this study was to test two hypotheses: firstly, that there is a different pattern of POMC mRNA expression in the human ovary of fertile and post-menopausal women, and secondly that there is a tissue-specific localization of POMC transcript. Northern blot analysis showed that a potential relationship exists between POMC gene expression and the reproductive age of a woman, and that POMC mRNA has a tissue-specific localization. The expression of POMC messenger in the ovarian parenchyma collected from women of fertile age and in the germinative follicles appeared higher than that observed in samples from post-menopausal women. No signals were detected in corpora lutea. In conclusion, we believe that the physiological role of the POMC gene in the human ovary remains an unsolved problem, necessitating more sensitive methods of mRNA detection as well as further studies in vitro
An increased vulnerability to stress is associated with a poor outcome of in vitro fertilization-embryo transfer treatment
No full textObjective: To evaluate the association between the vulnerability to stress and the treatment outcome of couples undergoing IVF-ET. Design: Controlled, prospective clinical study. Setting: The Assisted Reproduction Unit of the Department of Obstetrics and Gynecology, University of Modena. Patient(s): Forty-nine infertile women consecutively admitted to standard superovulation treatment. Mean age was 33.9 years, duration of infertility was 6.3 years. Reasons for assisted reproduction were mechanical factor in 22 cases, sperm problem in 9 cases, and endocrine disorder in 6 cases. In 12 cases, infertility was unexplained. More than 55% already had an IVF-ET attempt. Intervention(s): The day of oocyte pick-up, subjects were submitted to Stroop Color and Word test, a task measuring the ability to cope with a cognitive stressor, involving attentional and sympathoadrenal systems. Systolic (SEP) and diastolic blood pressure, as well as heart rate (HR) were measured at baseline, during the test, and 10 minutes after the end of testing. Main Outcome Measure(s): The evidence of a biochemical pregnancy (beta-hCG value 12 days after ET) define the success and failure groups. Result(s): Sixteen women (33%) had a biochemical pregnancy, 12 also had ultrasound evidence. Eight gave birth to healthy infants. Age, education, causes, and duration of infertility were similar in the success and failure groups. The latter were more involved in a job outside home than the former. Moreover, they had a lower number of both fertilized oocytes and transferred embryos. In response to the Stroop test, every subject reported an increase of cardiovascular parameters. However, women becoming pregnant showed a lower response of both SEP and HR than women who failed. Conclusion(s): Both a major cardiovascular vulnerability to stress and working outside home are associated to a poor outcome of IVF-ET treatment
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
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