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BackgroundThird trimester growth scans represent a significant proportion of the workload in obstetric ultrasound departments. The objective of these serial growth scans is to improve the antenatal detection of babies with fetal growth restriction. The aim of this paper is to describe a method of peer review for third trimester abdominal circumference measurements which is realistic within busy obstetric ultrasound departments in the UK.MethodTwenty-two, third trimester, measured abdominal circumference images were randomly selected. Images were assessed subjectively by 12 sonographers using the image Criteria Achieved Score. For quantitative assessment, termed the Inter-operator Variability Score, three of the abdominal circumference (AC) images were blindly remeasured. Following this, a questionnaire was used to ascertain which image criteria sonographers considered most important and to reach an agreement on correct caliper placement.ResultsThe least frequently met image criteria with the lowest Criteria Achieved Score related to an oblique abdominal circumference section. These included fetal kidney present (Criteria Achieved Score 24.6%), multiple oblique ribs (Criteria Achieved Score 39.4%) and oblique spine (Criteria Achieved Score 37.5%). Caliper placement was also identified as inconsistent.DiscussionThis study demonstrates that the perfect AC section is not always possible and sonographers use their professional judgement to determine whether an image is acceptable. Seventy-three percent of the images reviewed were of an acceptable standard. There can be inconsistencies in sonographer opinion regarding what is an acceptable third trimester abdominal circumference image. These differences need to be addressed to maximise the effectiveness of the third trimester ultrasound examination.ConclusionPeer review can be used to monitor scan quality and identify areas of inconsistency. 相似文献
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Kim PW Perl TM Keelaghan EF Langenberg P Perencevich EN Harris AD Song X Roghmann MC 《American journal of respiratory and critical care medicine》2005,171(6):616-620
RATIONALE: Health care-associated bloodstream infections are common in critically ill patients; however, investigators have had difficulty in quantifying the clinical impact of these infections given the high expected mortality among these patients. OBJECTIVE: To estimate the impact of health care-associated bloodstream infections on in-hospital mortality after adjusting for severity of illness at critical care admission. METHOD: A cohort of medical and surgical intensive care unit patients. MEASUREMENTS: Severity of illness at admission, bloodstream infection, and in-hospital mortality. MAIN RESULTS: Among the 2,783 adult patients, 269 developed unit-associated bloodstream infections. After adjusting for severity of illness, patients with a lower initial severity of illness who developed an infection had a greater than twofold higher risk for in-hospital mortality (hazard ratio [HR] = 2.42, 95% confidence interval [CI] 1.70, 3.44) when compared with patients without infection and with a similar initial severity of illness. In contrast, patients with a higher initial severity of illness who subsequently developed an infection did not have an increased risk for in-hospital mortality (HR = 0.96, 95%CI 0.76, 1.23) when compared with patients without infection but with a similar initial severity of illness. CONCLUSIONS: These results suggest that these infections in less ill patients have a higher attributable impact on subsequent mortality than in more severely ill patients. Focusing interventions to prevent bloodstream infections in less severely ill patients would be expected to have a greater benefit in terms of mortality reduction. 相似文献
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Nongnuj Tanphaichitr Kessiri Kongmanas Hathairat Kruevaisayawan Arpornrad Saewu Clarissa Sugeng Jason Fernandes Puneet Souda Jonathan B Angel Kym F Faull R John Aitken Julian Whitelegge Daniel Hardy Trish Berger Mark Baker 《Asian journal of andrology》2015,17(4):574-582
The interaction of sperm with the egg''s extracellular matrix, the zona pellucida (ZP) is the first step of the union between male and female gametes. The molecular mechanisms of this process have been studied for the past six decades with the results obtained being both interesting and confusing. In this article, we describe our recent work, which attempts to address two lines of questions from previous studies. First, because there are numerous ZP binding proteins reported by various researchers, how do these proteins act together in sperm–ZP interaction? Second, why do a number of acrosomal proteins have ZP affinity? Are they involved mainly in the initial sperm–ZP binding or rather in anchoring acrosome reacting/reacted spermatozoa to the ZP? Our studies reveal that a number of ZP binding proteins and chaperones, extracted from the anterior sperm head plasma membrane, coexist as high molecular weight (HMW) complexes, and that these complexes in capacitated spermatozoa have preferential ability to bind to the ZP. Zonadhesin (ZAN), known as an acrosomal protein with ZP affinity, is one of these proteins in the HMW complexes. Immunoprecipitation indicates that ZAN interacts with other acrosomal proteins, proacrosin/acrosin and sp32 (ACRBP), also present in the HMW complexes. Immunodetection of ZAN and proacrosin/acrosin on spermatozoa further indicates that both proteins traffic to the sperm head surface during capacitation where the sperm acrosomal matrix is still intact, and therefore they are likely involved in the initial sperm–ZP binding step. 相似文献
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East Africa was at the forefront of early achievements and discoveries in paediatric oncology thanks to Denis Burkitt's seminal work. Although these successes have been built upon and continued elsewhere, they were sadly not sustained in sub-Saharan Africa for a variety of reasons. In recent years however this situation is slowly changing in countries across the continent. Tanzania is one such African country. Until very recently, survival rates of 5-10% for all children's cancers were expected. However, change has been brought about thanks to the combined efforts and commitments of the Tanzanian Ministry of Health, non-governmental organizations--such as The International Network for Cancer Treatment and Research, and Children in Crossfire-- and the participation of the private sector. Services are rapidly developing and outcomes are continuing to improve with 1-year survival rates of approximately 60% achieved. Efforts to maintain this early progress are concentrated around providing high quality local subspecialty medical training and continued local ownership of the programme. 相似文献
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