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排序方式: 共有605条查询结果,搜索用时 15 毫秒
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Prenatal ultrasound diagnosis of clubfoot 总被引:1,自引:0,他引:1
Five cases of congenital clubfoot diagnosed prenatally by ultrasound are reported. The incidence of clubfoot may be higher within an affected family and may be associated with other structural anomalies or chromosomal abnormalities. Identifying a clubfoot in utero should therefore alert the sonographer that other anomalies may be present and should lead to a detailed structural survey. 相似文献
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Rosen BR; Fleming DM; Kushner DC; Zaner KS; Buxton RB; Bennet WP; Wismer GL; Brady TJ 《Radiology》1988,169(3):799
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To optimally develop or adjust national contingency plans to respond to the next influenza pandemic, we developed a decision type model and estimated the total health burden and direct medical costs during the next possible influenza pandemic in the Netherlands on the basis of health care burden during a regular epidemic. Using an arithmetic decision tree-type model we took into account population characteristics, varying influenza attack rates, health care consumption according to the Dutch health care model and all-cause mortality. Actual direct medical cost estimates were based on the Dutch guidelines for pharmaco-economic evaluation. In the base-case scenario with no preventive measure available and an average influenza attack rate of 30%, 4,958,188 influenza infections, 1,552,687 GP consultations, 83,515 hospitalizations and 173,396 deaths will take place in The Netherlands. The burden is highest in adults aged 20 to 64 years. If minimizing the total mortality and sustaining highest net economic returns is the objective, this group needs to be targeted in interventions. 相似文献
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Anwar AM Geleijnse ML Ten Cate FJ Meijboom FJ 《Interactive Cardiovascular and Thoracic Surgery》2006,5(6):683-687
Tricuspid annulus (TA) evaluation continues to be a major problem in the surgical decision-making process. Obviously, 2-dimensional transthoracic echocardiography (2D TTE) is limited in TA visualization due to its complex 3D shape. The study aimed to determine TA morphology, size and function with real-time three-dimensional echocardiography (RT3DE) in 40 patients divided into two equal groups (I: normal TA and II: dilated). 2D TTE measurements included TA diameter (TAD) at apical 4-chamber (AP4CH) and parasternal short axis (PSAX) views. RT3DE measurements included TA area (TAA), major TAD and minor TAD. TA fractional shortening (TAFS), and TA fractional area change (TAFAC) were calculated from end-systolic and end-diastolic measurements. RT3DE allowed visualization and measurement of the entire oval-shaped TA in all patients irrespective of its size (normal or dilated). 2D TTE measurement of TAD at both AP4CH and at PSAX views was significantly smaller than the major TAD measured by RT3DE (P<0.0001) and nearly matched with the minor TAD in all patients. Calculation of TAFS was comparable with both techniques. TAFAC was significantly higher than TAFS (P<0.0001). So, RT3DE could be relied on more accurately than 2D TTE in the assessment of TA size and function which may aid in decision-making and selection of proper surgical procedure when indicated. 相似文献
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Greif WL; Buxton RB; Lauffer RB; Saini S; Stark DD; Wedeen VJ; Rosen BR; Brady TJ 《Radiology》1985,157(2):461-466
Paramagnetic agents enhance contrast between tissues in magnetic resonance (MR) imaging by altering tissue relaxation times. The effect of these changes on MR image intensity depends in part on the choice of operator-controlled pulse sequence parameters. With the newly described paramagnetic hepatobiliary contrast agent, iron(III) ethylenebis-(2-hydroxyphenylglycine), Fe(EHPG)-, an in vivo experimental analysis of pulse sequence optimization was performed on the rat. We compared the enhancement of the liver divided by background noise, EL/N, of standard inversion-recovery (IR) and spin-echo (SE) T1-weighted pulse sequences and several pulse sequences theoretically predicted to have improved EL/N. Optimization of the echo time (TE = TEmin) gave a substantial (greater than 60%) increase in EL/N over the standard IR and SE pulse sequences. Images obtained with optimized repetition rate and inversion time gave only a slight additional improvement. Within the uncertainties of our relaxation measurements, the measured changes in EL/N with pulse sequence optimization corresponded well with theoretical predictions. With the experimental and theoretical data, the importance of using a short echo time to obtain maximal T1 contrast in contrast-enhanced MR imaging and the relative merits of optimized SE versus IR pulse sequences for contrast-enhanced MR imaging are discussed. 相似文献
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