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Cellular effects of diagnostic doppler ultrasound on murine spermatogenic cells monitored by flow-cytometry
No full textA study has been carried out to investigate the possible effects caused by Doppler diagnostic ultrasound on murine spermatogenesis. The frequency of the different types of cells has been analyzed using flow cytometry. Exposure to ultrasound was carried out using a commercial device used in diagnostic conditions. Male hybrid mice were exposed to ultrasound for 30 min and observed from 7 to 35 days after treatment. Flow cytometrical analysis showed changes in the relative frequency of the elongated spermatids and this was used as an end-point. A statistically significant decrease in the frequency of this cell type was observed after 7 and 35 days with both pulsed and continuous ultrasound. With the former, a decrease was also seen in this compartment after 14 and 21 days. Our results have shown that diagnostic ultrasound used in the Doppler technique induces effects on specific cell types of murine spermatogenesis
Donna - Gravidanza - Sport, Atti del workshop: La donna e l'attività fisica : Padova-Venezia, 26-30 ottobre 1994
No full textFlow cytometric and cytogenetic analyses in human spontaneous-abortions
No full textCytogenetic and flow cytometric analyses were performed on 38 human spontaneous abortions in an attempt to obtain information on karyotype abnormalities and to compare the two approaches of analysis. In 19 cases, it was not possible to perform cytogenetic analysis because too long a time had passed between surgical sampling and cell culture, and in vitro culture failed. Of the 19 cases analyzed, 10/19 showed a normal karyotype and 5/19 showed a single trisomy (2/5 trisomies involved chromosome 16, 115 trisomy involved chromosome 18. 1/5 trisomy involved chromosome 20, and 1/5 was Klinefelter syndrome). Of the remaining 4/19 cases, 2/19 showed a polyploid condition (1 tetraploidy and 1 triploidy), 1/19 a double trisomy (chromosomes 13 and 21), and 1/19 a pentasomy of the sex chromosomes (49,XXXXY). Flow cytometric analysis was performed on all abortive samples. The samples were subdivided, when possible, into two portions conventionally named ''amniotic'' and ''chorionic'', using the amniotic membrane as an anatomical reference. Maternal blood lymphocytes were used as a diploid standard for each sample. In the 19 cases not analyzed by the cytogenetic approach, flow cytometric analysis showed 9 diploid and 10 aneuploid DNA distributions. In the remaining 19 cases, analyzed with both approaches, the comparison of DNA estimations using cytogenetic and flow cytometric analyses showed good agreement. In the cases with karyotype abnormalities, flow cytometric measurement provided evidence of an alteration of DNA content with respect to the diploid standard. Flow cytometric analysis showed a diploid distribution, whereas cytogenetic analysis revealed chromosomal abnormalities in only 4/19 cases. These discordant results could be related to mosaic conditions or maternal cell contamination, Moreover, cytogenetic and flow cytometric analyses were performed on 2 amniotic cell cultures, and concordant results were obtained. The results obtained suggest that a combination of these techniques is beneficial in attempts to obtain information about DNA content alterations, even when cultures fail, and in screening studies of human abortions
Going 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
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
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