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We report three cases that reveal an array of etiologic and radiologic findings associated with dissection of the proximal segment of the vertebral arteries. Regardless of etiology, the proximal segment may be the principal site of dissection in these vessels.  相似文献   
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Computed tomography (CT) has become essential in the diagnostic evaluation of the female pelvic. CT allows accurate delineation of neoplastic and inflammatory processes and provides an effective means of guiding percutaneous needle biopsy of masses and aspiration/drainage of fluid collections. In the pregnant woman, pelvimetry and excretory urography can be performed using the CT scout view with a radiation dose significantly lower than with conventional x-ray techniques. This paper covers the clinically relevant technical considerations involved in performing CT on women and follows with an overview of normal female pelvic anatomy and frequently encountered pathologic conditions.  相似文献   
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The correct identification of syndromes and other congenital malformations at an early age is critical for the child, family and care providers. Most specialists who conduct large screenings of young children are not adequately trained to recognize signs and symptoms that should lead to appropriate referral to the clinical geneticist and/or diagnostic team. A systematic approach for recognizing important signs is presented here; a Craniofacial Screening Profile. Following a brief training program, the Profile was validated by 39 speech-language pathologists in screening 3,539 kindergarten and first grade children. The results were excellent (specificity was 99.6%), demonstrating that with limited training, specialists can effectively screen for important signs and symptoms of a major group of syndromes and other congenital malformations.  相似文献   
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We recorded the electro-oculogram from 27 normal subjects by means of green and near-ultraviolet (UVA) stimulation. After a 40-minute dark-adaptation period, baseline responses were recorded. In response to the green stimulus, the electro-oculogram increased from this level by an average (± standard error of the mean) of 49.5% ±4.0%. Although the predicted scotopic effectiveness of the ultraviolet stimulus was more than 3 log units below that of the green stimulus, the near-ultraviolet-induced electro-oculogram increased to an average of 21.9% ±3.0% above baseline. This response cannot be due to lens fluorescence to the near-ultraviolet stimulus, since two aphakic subjects had electro-oculographic responses of 32% and 76% above baseline to near-ultraviolet stimuli. Neither the green nor the ultraviolet electro-oculogram changed significantly with age. These large responses to near-ultraviolet stimulation demonstrate the need for standardizing light sources for electro-oculographic testing because the degree of near-ultraviolet irradiance varies considerably according to their design characteristics.  相似文献   
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The authors report on the relationship of early adolescent substance use (up to the time of the 16th birthday) to educational-vocational performance in the early adulthood of 612 African-American urban subjects. Voluminous prospective data were available on the behavior, test performance, and families of 612 urban African-American subjects, from birth up to 7 years of age. Scarcer prospective data were available for school performance during later years of school. Control variables were derived from these data to determine the amount of variance in each dependent educational-vocational outcome variable that was accounted for, independently of the amount of variance accounted for by early substance use. (American Journal on Addictions 1994; 3:325–336)  相似文献   
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