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Magnetic resonance (MR) angiography has significantly reduced the need for diagnostic conventional angiography and is preferred over CT angiography in children because of its lack of ionizing radiation. The availability of gadofosveset trisodium (the only clinically approved blood pool MR contrast agent) has led to an increase in applications of MR for vascular imaging and an improvement in diagnostic quality of MR angiography. Gadofosveset is a gadolinium-based contrast agent that binds reversibly to albumin, resulting in increased paramagnetic effect and longer intravascular residence. This allows for high-resolution arterial and venous MR angiography, assessment of flow characteristics of vascular malformations, dynamic vascular imaging, and multi-station imaging with a single low-dose gadolinium contrast injection. The purpose of this pictorial essay is to facilitate understanding of the kinetics and safety profile of gadofosveset trisodium, discuss technical aspects of imaging, and illustrate advantages and extracardiac applications in pediatric body imaging. 相似文献
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Andrew S. Bowman Sarah W. Nelson Shannon L. Page Jacqueline M. Nolting Mary L. Killian Srinand Sreevatsan Richard D. Slemons 《Emerging infectious diseases》2014,20(9):1472-1480
Agricultural fairs provide an opportunity for bidirectional transmission of influenza A viruses. We sought to determine influenza A virus activity among swine at fairs in the United States. As part of an ongoing active influenza A virus surveillance project, nasal swab samples were collected from exhibition swine at 40 selected Ohio agricultural fairs during 2012. Influenza A(H3N2) virus was isolated from swine at 10 of the fairs. According to a concurrent public health investigation, 7 of the 10 fairs were epidemiologically linked to confirmed human infections with influenza A(H3N2) variant virus. Comparison of genome sequences of the subtype H3N2 isolates recovered from humans and swine from each fair revealed nucleotide identities of >99.7%, confirming zoonotic transmission between swine and humans. All influenza A(H3N2) viruses isolated in this study, regardless of host species or fair, were >99.5% identical, indicating that 1 virus strain was widely circulating among exhibition swine in Ohio during 2012. 相似文献
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Shannon Stogryn Jennifer Metcalfe Ashley Vergis Krista Hardy 《Canadian journal of surgery》2016,59(1):12-18
BackgroundUltrasonography (US) is the mainstay of biliary tract imaging, but few recent studies have tested its ability to diagnose acute cholecystitis (AC). Our objective was to determine how well a US diagnosis of AC correlates with the intraoperative diagnosis. We hypothesize that US underestimates this diagnosis, potentially leading to unexpected findings in the operating room (OR).MethodsThis retrospective review included all patients admitted to the acute care surgical service of a tertiary hospital in 2011 with suspected biliary pathology who underwent US and subsequent cholecystectomy. We determined the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of US using the intraoperative diagnosis as the gold standard. Further analysis identified which US findings were most predictive of an intraoperative diagnosis of AC. We used a recursive partitioning method with random forests to identify unique combinations of US findings that, together, are most predictive of AC.ResultsIn total, 254 patients underwent US for biliary symptoms; 152 had AC diagnosed, and 143 (94%) of them underwent emergency surgery (median time to OR 23.03 hr). Ultrasonography predicted intraoperative findings with a sensitivity of 73.2%, specificity of 85.5% and PPV of 93.7%. The NPV (52.0%) was quite low. The US indicators most predictive of AC were a thick wall, a positive sonographic Murphy sign and cholelithiasis. Recursive partitioning demonstrated that a positive sonographic Murphy sign is highly predictive of intraoperative AC.ConclusionUltrasonography is highly sensitive and specific for diagnosing AC. The poor NPV confirms our hypothesis that US can underestimate AC. 相似文献
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Immediate Post-Abortion Insertion of Intrauterine Contraceptives (IUC) in a Diverse Urban Population
DeShawn Taylor Shannon Connolly Sue Ann Ingles Carey Watson Penina Segall-Gutierrez 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(3):416-421
Ethnic minority women have a higher incidence of unintended pregnancy and abortion than Caucasian women, with significant individual and social implications. Post-abortion intrauterine contraceptive (IUC) use may reduce future unintended pregnancy. This was a retrospective review of 265 women undergoing abortion at a Los Angeles County Reproductive Options Clinic. Demographic factors, reproductive history, and post-abortion contraceptive choice were evaluated and analyzed. The population was predominantly Latina (73 %) and single, with a mean age of 27. Immediate post-abortion IUC insertion was chosen by 48 % overall and more frequently by Latinas (55 %) than by African Americans (33 %) or Asians (43 %) (p = 0.02). IUC use increased with age, undesired future fertility, increasing gravidity, and history of previous abortion in univariate analysis. In multivariate analysis, IUC use increased with Latina ethnicity and increasing gravidity. In a clinic serving low-income urban women in Los Angeles, post-abortal IUC uptake is highest among Latinas and those with prior pregnancies. Future research should examine reasons for and barriers to IUC uptake in diverse communities and methods to improve post-abortion IUC uptake to prevent subsequent unintended pregnancies. 相似文献