1,720,957 research outputs found
Ruolo della chirurgia laparoscopica nel trattamento dell’infertilità prima dell’applicazione di tecniche di procreazione medicalmente assistita.
No full textEvaluation of pregnancy rate in cycles of freezing IVF zygotes using the freezing of embryos
No full textAbstract of Proceedings- 2011
http://www.fissr.dbabstract.com/US/US_Upd.aspx?IDA=1450
06/04/2011 Gruppo Imatìka
1° Congresso FISSR – Riccione - 26-28 Maggio 2011
EVALUATION OF PREGNANCY RATE IN CYCLES OF FREEZING IVF ZYGOTES USING THE FREEZING OF EMBRYOS
R. Laganara1, M. Gangemi1, M. L. Coronella1, A. Riva', G. B. Nardelli1
Dpt Gynecological Science and Human Reoproduction – University of Padova-Italy
The optimization results of a cycle of in vitro fertilization is achieved with a high cumulative rate of pregnancy for each pick-up.
To achieve this result it is necessary to adopt a program of cryopreservation that maximizes the results.
Freezing can be done at the stage of pronuclei (zygote) or to cells (embryos). In some countries, like Switzerland and Germany, freezing at the pronuclear stage is only allowed by law, considering that this is acceptable from an ethical point of view.
Much literature also highlights the best pregnancy rate (PR) obtained with the freezing of zygotes compared to that of embryos. We wanted to verify this finding in our series.
Were evaluated retrospectively 260 cycles of transference of embryos thawed, divided into two groups of 130: group 1 includes frozen embryos to the stage of pronuclei (PN) (day 1 after the egg retrieval; 20-22 hours after insemination) and group 2 embryos frozen at the stage of 2-4 cells (day 2 after egg retrieval, 44-46 hours after insemination).
The transference was always done on natural cycle, with ovulation by plasmatic monitoring of E2, progesterone and LH ; the zygotes were thawed the day before the transfer and maintained in culture for 24 hours already cleaved embryos were thawed the day of transfer.
According to the age of the patient and the number of embryos available have been transferred from 1 to 3 embryos. We evaluated the PR by determination of HCG 14 days after the transfer and viewing of an amniotic sac with fetal cardiac activity after 28 days of transfer.
The PR was higher in group 1 (19.23% - 25/130) than in group 2 (15.38% -20 / 130), with a difference not statistically significant (P = Q, 3 \).
The freezing to the zygote stage provides a PR greater than the freezing stage of embryo cleaved, albeit with a difference not statistically significant. Whereas, in the zygote, the fusion of genetic material of two parents in the genetic makeup of the new embryo has not yet occurred, the cryopreservation of zygotes can be more easily accepted by the ethical point of view, as well as provide better result
Could empirical low-dose-aspirin administration during IVF cycle affect both the oocytes and embryos quality via COX 1-2 activity inhibition?
No full textPURPOSE:
To compare qualitative and quantitative ovarian response in idiopathic infertile women treated with low-dose-aspirin (LDA) during in-vitro-fertilization (IVF) cycles (pl) versus untreated ones.
METHODS:
We conducted an observational-cohort-study on normo-responders patients aged between 25 and 45 years referred to Assisted-Reproductive Unit - University of Padua - in order to evaluate the ovarian response effects (both qualitative and quantitative) after LDA administration. In detail we aim to assess if LDA administration could improve ovarian response, reducing the gonadotropin administration, and if its administration could increase the amount of follicles greater than 16 mm at pick-up, the amount and quality of oocytes retrieved, the amount and quality of embryos, the chance to achieve a pregnancy and to carry it on.
RESULTS:
One hundred six LDA-treated patients (Group-A) and 100 not-treated ones (Group-B) were homogeneous for age and BMI. The Group-A, compared to Group-B, showed higher gonadotropin request, higher number of ovarian follicles at pick-up, more follicles bigger than 16 mm in diameter and more retrieved oocytes (despite higher number of immature and at germinal vesicle stage oocytes) but lower quality of obtained embryos. The comparison between two Groups in term of retrieved oocytes /number of follicles, mature oocytes/retrieved oocytes, fertilized oocytes/mature oocytes and good embryos quality/mature oocytes showed a strongly advantageous ratio for Group-B. For each considered outcome, we found a dose-related effect.
CONCLUSIONS:
It is mandatory to define which patients could benefit from LDA administration and the adequate timing to administer it since the empirical administration could negatively affect both oocyte and embryo quality during IVF cycles
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
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