1,720,983 research outputs found
Transabdominal uterine artery Doppler between 11 and 14 weeks of gestation for the prediction of outcome in high-risk pregnancies
Objective. To assess the value of early transabdominal uterine artery Doppler ultrasound for the prediction of gestational outcomes in pregnancies at high risk for preeclampsia. Methods. This was an observational study. Doppler ultrasound of the uterine arteries at 11-14 weeks of gestation was performed in 76 women at high risk for preeclampsia. Abnormal uterine Doppler was defined by the presence of bilateral notching or by a mean resistance index (RI) >0.80. Adverse outcomes evaluated were preeclampsia, fetal growth restriction, placental abruption, intrauterine death, and complications requiring delivery before 34 weeks of gestation. Results. Among 76 women, 30 (39%) had abnormal uterine Doppler and 46 (61%) had normal Doppler waveform configuration and RI. Abnormal uterine flow was related to a significantly higher incidence of preeclampsia (17% vs. 0%; p = 0.0041), fetal growth restriction (27% vs. 0%; p = 0.0002), intrauterine death (13% vs. 0%; p = 0.0109), and iatrogenic preterm delivery (20% vs. 2%; p = 0.0086). When the Doppler was normal, the negative predictive value for complications requiring delivery before 34 weeks was 98%. Conclusions. Normal impedance to flow in uterine arteries between 11 and 14 weeks of gestation is strongly related to a normal pregnancy outcome in women at high risk for preeclampsia. © 2008 Informa UK Ltd
Transabdominal uterine artery Doppler between 11 and 14 weeks of gestation for the prediction of outcome in high-risk pregnancies.
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
Uterine artery velocimetry in patients with gestational hypertension
OBJECTIVE:
To evaluate whether abnormal uterine artery velocimetry in patients with pregnancy-induced hypertension is more predictive of the outcome of pregnancy than the presence of proteinuria and the severity of hypertension.
METHODS:
A retrospective study was conducted on 344 hypertensive pregnant women who underwent uterine artery Doppler investigation. Patients were classified as either preeclamptic or with gestational hypertension at follow-up 2 months after delivery. Pregnancy outcomes of patients with preeclampsia and gestational hypertension were correlated to uterine artery velocimetry. A further analysis was done dividing patients into mild and severe groups.
RESULTS:
An abnormal uterine Doppler was related to a significantly earlier week of delivery (32.5 versus 35.3 in preeclampsia, 33.6 versus 38.1 in gestational hypertension), a lower mean birth weight (1494 g versus 2320 g in preeclampsia, 1690 g versus 2848 g in gestational hypertension), and a higher number of growth-restricted fetuses (70% versus 23% in preeclampsia, 75% versus 20% in gestational hypertension). In both mild and severe hypertensive groups, abnormal uterine velocimetry was associated with a worse pregnancy outcome (delivery at week 33.1, versus 37.9 in the mild group; 32.7 versus 37.3 in the severe group; birth weight 1574 g versus 2741 g in the mild group; 1539 g versus 2742 g in the severe group). A multivariable analysis of the presence of proteinuria, severity of hypertension, and uterine Doppler revealed that only an abnormal uterine Doppler was significantly related to adverse perinatal outcome (P <.001).
CONCLUSION:
Abnormal uterine Doppler was the variable that was more frequently associated with adverse pregnancy outcome
Appropriate Similarity Measures for Author Cocitation Analysis
We 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
Doppler-velocimetria delle arterie uterine nel I° trimestre in una popolazine ad alto rischio
Dispelling the Myths Behind First-author Citation Counts
We 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
- …
