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41.
Digital mammography using storage phosphor CR is still in the investigational stage. It is the only digital mammography system that has been tested in preliminary clinical trials with promising early results. Further clinical studies are needed to assess the impact of the limited spatial resolution of storage phosphor technology on its application as a digital screening mammography system. Further studies also are needed to determine the optimum image processing parameters needed in digital mammography.  相似文献   
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African Americans are at increased risk for cancer and represent an important target population for programs such as Healthy People 2000, the Cancer Information Service (CIS), and the 5 a Day for Better Health Initiative. Yet, awareness of such programs among rural blacks is unknown. This study assessed awareness of these programs and determined related knowledge and beliefs among rural African Americans. It was undertaken as part of the baseline survey for the Black Churches United for Better Health project, a National Cancer Institute-funded initiative. A minority of respondents (n = 3737) demonstrated name recognition of Healthy People 2000 (23.4%), the CIS (42.4%), and the 5 a Day Program (40.7%). Far fewer (7.4%) were able to correctly identify the recommended daily number of servings of fruits and vegetables. Reported family history of cancer was associated with a greater tendency believe that eating more fruits and vegetables can prevent disease. These findings underscore the need for efforts to reach the rural black community with culturally sensitive and stage appropriate cancer prevention messages. Knowledge of family history of cancer may play an important role in targeting subgroups and delivering effective cancer prevention messages.  相似文献   
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PURPOSETo determine whether plain films alone are sufficient in the evaluation of stability of simple wedge-compression fractures of the lumbar spine.METHODSPlain films and CT scans of 53 consecutive patients seen during a 2-year period with lumbar spine fractures were retrospectively reviewed. Six readers blinded to the CT diagnosis independently read each patient''s plain films. Plain-film findings were scored on a five-point graded response scale using criteria proposed by Gehweiler and Daffner. In addition, a fracture was considered to be possibly unstable if there was involvement of more than one vertebral level or greater than 50% loss of anterior vertebral body height. CT findings represented the standard for comparison. CT scans were independently evaluated by three additional readers. Two-column involvement, middle-column involvement alone but with retropulsion, multiple-level involvement, or greater than 50% loss of vertebral height indicated potential instability.RESULTSFor 14 stable and 39 potentially unstable lumbar spine fractures, the pooled (mean) plain-film negative predictive value for detection of potentially unstable fractures was 0.62 (95% confidence interval, 0.53 to 0.70), with a sensitivity of 0.83 (95%, confidence interval; 0.78 to 0.87), and specificity of 0.80 (95% confidence interval, 0.70 to 0.87).CONCLUSIONPlain films are not adequate for determining stability of lumbar spine fractures.  相似文献   
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We report a re-do case of severe aortic valve stenosis due to pannus formation 29 years after an aortic Starr-Edwards caged-ball valve implantation. A huge shelf of calcified and thick pannus tissue below the valve had reduced the already small orifice by at least a third in surface area. The explanted Starr-Edwards valve revealed no mechanical or structural failure. Early detection and treatment of pannus outgrowth is essential in order to prevent life-threatening prosthetic valve malfunctions.  相似文献   
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Cardiovascular disease (CVD), which includes myocardial infarction(MI), stroke, and peripheral vascular disease, remains the leading cause of death in the United States and in most developed countries. In the United States today, 25% of patients have metabolic syndrome-including those who have had a prior occlusive vascular disease event, those who are having an acute MI or ischemic stroke, and finally, the largest segment of the population,namely those who have not yet experienced a clinical CVD, but whose risks are substantial (10-year risk 10%). This article reviews the totality of evidence for aspirin in the treatment and prevention of CVD and emphasizes its importance as adjunctive therapy for patients with metabolic syndrome.  相似文献   
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Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using interventioanl radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment' of biliary strictures are discussed.  相似文献   
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