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Magnetic resonance imaging and placenta previa   总被引:3,自引:0,他引:3  
Twenty-five women with diagnoses of placenta previa on ultrasound examination underwent magnetic resonance imaging examination. An assessment of placental position and the relationship of the lower placental edge to the internal os was made with both techniques and the results were compared. There was complete correlation of placental localization but significant differences were found in the determination of the degree of placenta previa. This occurred more often with posteriorly situated placentas. Magnetic resonance imaging directly affected management with regard to delivery in seven cases. Magnetic resonance imaging provides a technique capable of accurately assessing placental position and its relationship to the cervix, thereby leading to a reduction in hospitalization and inappropriate operations.  相似文献   
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STATEMENT OF PROBLEM: Maxillofacial prostheses require frequent replacement because the elastomer and its color additives undergo changes. PURPOSE: This study attempted to determine whether predictable color changes occur when 3 pigments are individually incorporated into a specific silicone elastomer. MATERIAL AND METHODS: The materials included an RTV elastomer; 1 natural inorganic pigment, burnt sienna; and 2 synthetic organic pigments, Hansa yellow and alizarin red. Eight test groups of 10 polymerized specimens were established. Groups 1 and 2, acting as the control, involved only the elastomer. Groups 3 and 4 were composed of elastomer and burnt sienna. Groups 5 and 6 consisted of elastomer and Hansa yellow. Groups 7 and 8 comprised elastomer and alizarin red. Odd-numbered groups were assigned to a test site in Miami, Fla., whereas the even numbered groups went to Phoenix, Ariz. Specimens weathered in Miami and Phoenix received sunlight exposures of 1305.7 MJ/m2 and 1310.2 MJ/m2, respectively, over time. Before and after weathering, the L* a* b* color parameter (DeltaE*) of each specimen was determined spectrophotometrically. RESULTS: Mean color changes that occurred in Arizona were larger than those produced in Florida. Specifically, these differences ranged from 0.4 (alizarin red groups) to 2.36 units for the 2 unpigmented control groups. Other differences showed significance for the unpigmented (P=.001), burnt sienna (P=.006), and Hansa yellow groups (P=.001). CONCLUSION: Outdoor weathering tests in which documented ASTM methods were used provided a valid baseline for future research on color changes in maxillofacial prostheses.  相似文献   
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The objective of the HGF-STAT clinical trial is to determine whether perfusion can be improved by gene transfer with a plasmid DNA containing hepatocyte growth factor (HGF) in the affected limb of patients with unreconstructable critical limb ischemia (CLI). CLI results in a high rate of limb loss and impaired quality of life. The current therapeutic strategies, including bypass surgery and percutaneous interventions, are only successful in treating a subset of patients. Therapeutic angiogenesis is an investigational method that seeks to favorably impact tissue perfusion in CLI. HGF-STAT is a double-blind, parallel-group, placebo-controlled, dose-response study in 100 patients with unreconstructable CLI. Eligible subjects will be randomized 1:1:1:1 to receive saline placebo or one of three dose/regimens of HGF plasmid DNA. The selection of outcome measures, including the primary endpoint, and changes in transcutaneous oxygen pressure (TcPO2) from baseline to 3 months will be discussed. In conclusion, this study will help to determine whether therapeutic angiogenesis with HGF is a viable option in the treatment of patients with CLI.  相似文献   
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PURPOSE: The large and well-characterized population of acute myocardial infarction (AMI) patients studied in the recently completed Enhancing Recovery in Coronary Heart Disease (ENRICHD) multicenter clinical trial provides a unique opportunity to examine the importance of self-reported regular physical exercise in a large cohort of patients with a recent AMI who are depressed or report low levels of social support. METHODS: We prospectively examined the association between self-reported physical exercise and all-cause mortality and cardiovascular morbidity among 2078 men (N = 1175; 56.5%) and women (N = 903; 43.5%) with an AMI participating in the ENRICHD Trial. Six months after suffering an AMI, patients were surveyed about their exercise habits and were then followed for up to 4 yr. RESULTS: During an average 2 yr of follow-up, 187 fatal events occurred. Patients reporting regular exercise had less than half the events (5.7%) of those patients reporting they did not regularly exercise (12.0%). After adjustment for medical and demographic variables, the hazard ratio for fatal events was 0.62 (95% CI = 0.44-0.86, P = 0.004). The rate of nonfatal AMI among the exercisers was 6.5% compared with 10.5% who reported no regular exercise. After adjustment for covariates, the hazard ratio for nonfatal AMI was 0.72 (95% CI = 0.52-0.99, P = 0.044). CONCLUSIONS: The present findings demonstrate the potential value of exercise in reducing mortality and nonfatal reinfarction in AMI patients at increased risk for adverse events by virtue of their either being depressed or having low social support.  相似文献   
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