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排序方式: 共有8023条查询结果,搜索用时 15 毫秒
1.
George Haddad Malte Klling Urs A. Wegmann Angela Dettling Harald Seeger Roland Schmitt Inga Soerensen-Zender Hermann Haller Andreas D. Kistler Anne Dueck Stefan Engelhardt Thomas Thum Thomas F. Mueller Rudolf P. Wüthrich Johan M. Lorenzen 《Journal of the American Society of Nephrology : JASN》2021,32(2):323
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Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
Background
The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.Methods
A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.Results
Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.Conclusions
In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler. 相似文献3.
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Holger W. Unger Stephan Karl Regina A. Wangnapi Peter Siba Glen Mola Jane Walker Ivo Mueller Maria Ome Stephen J. Rogerson 《The American journal of tropical medicine and hygiene》2015,92(1):178-186
We conducted a prospective longitudinal study of fetal size in rural Papua New Guinea (PNG) involving 439 ultrasound-dated singleton pregnancies with no obvious risk factors for growth restriction. Sonographically estimated fetal weights (EFWs; N = 788) and birth weights (N = 376) were included in a second-order polynomial regression model (optimal fit) to generate fetal weight centiles. Means for specific fetal biometric measurements were also estimated. Fetal weight centiles from a healthy PNG cohort were consistently lower than those derived from Caucasian and Congolese populations, which overestimated the proportion of fetuses measuring small for gestational age (SGA; < 10th centile). Tanzanian and global reference centiles (Caucasian weight reference adapted to our PNG cohort) were more similar to those observed in our cohort, but the global reference underestimated SGA. Individual biometric measurements did not differ significantly from other cohorts. In rural PNG, a locally derived nomogram may be most appropriate for detection of SGA fetuses. 相似文献
6.
MRI accurately identifies early murine mammary cancers and reliably differentiates between in situ and invasive cancer: correlation of MRI with histology 下载免费PDF全文
Devkumar Mustafi Marta Zamora Xiaobing Fan Erica Markiewicz Jeffrey Mueller Suzanne D. Conzen Gregory S. Karczmar 《NMR in biomedicine》2015,28(9):1078-1086
MRI methods that accurately identify various stages of mouse mammary cancer could provide new knowledge that may have a direct impact on the management of breast cancer in patients. This research investigates whether we can accurately follow the progression from in situ to invasive cancer by the evaluation of in vivo and ex vivo MRI, and in comparison with histology as the gold standard for the diagnosis and staging of cancer. Six C3(1)SV40Tag virgin female mice, aged 12–16 weeks, were studied. At this age, these mice develop in situ cancer that resembles human ductal carcinoma in situ (DCIS). Fast spin‐echo images of inguinal mammary glands were acquired at 9.4 T. After in vivo MRI, mice were sacrificed; inguinal mammary glands were excised and fixed in formalin for ex vivo MRI. Three‐dimensional, volume‐rendered, in vivo and ex vivo MR images were then correlated with histology. High‐resolution ex vivo scans facilitated the comparison of in vivo scans with histology. The sizes of mammary cancers classified as in situ on the basis of histology ranged from 150 to 400 µm in largest diameter, and the average signal intensity relative to muscle was 1.40 ± 0.18 on T2‐weighted images. Cancers classified as invasive on the basis of histology were >400 µm in largest diameter, and the average intensity relative to muscle on T2‐weighted images was 2.34 ± 0.26. Using a cut‐off of 400 µm in largest diameter to distinguish between in situ and invasive cancers, a T2‐weighted signal intensity of at least 1.4 times that of muscle for in situ cancer, and at least 2.3 times that of muscle for invasive cancer, 96% of in situ and 100% of invasive cancers were correctly identified on in vivo MRI, using histology as the gold standard. Precise MRI–histology correlation demonstrates that MRI reliably detects early in situ cancer and differentiates in situ from invasive cancers in the SV40Tag mouse model of human breast cancer. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Evelyn Xiu Ling Loo Hui Xing Lau Noor Hidayatul Aini Suaini Lydia Su Yin Wong Anne Eng Neo Goh Oon Hoe Teoh Hugo PS Van Bever Lynette Pei-chi Shek Bee Wah Lee Kok Hian Tan Keith M. Godfrey Johan Gunnar Eriksson Yap Seng Chong Elizabeth Huiwen Tham 《Pediatric allergy and immunology》2021,32(5):1096-1099
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