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Pretreatment serum samples obtained at diagnosis from 89 children with various pediatric malignancies were examined for circulating immune complexes (CIC) using the [125I]Clq binding assay. The study population consisted of 35 children with acute lymphocytic leukemia (ALL), 22 children with acute non-lymphocytic leukemia (ALL), 24 with neuroblastoma (NB), and eight with osteosarcoma (OS). Concomitant quantitation of immunoglobulins was performed in 55 patients, revealing normal values for age. Increased levels of CIC at diagnosis were found in 9%, 22%, 42%, and 50% of children with ALL, AML, NB, and OS, respectively. Except for a higher proportion of CIC-positive patients observed in stage IV NB (nine of 17) compared to stage I-III NB (one of seven), no correlation was observed between initial CIC level and presenting clinical features, response to treatment, prognosis, or presence of infection. Longitudinal sampling of six NB and two OS patients did not reveal a clear relationship between disease activity and quantity of CIC. For the pediatric malignancies studied, these data demonstrate minimal value in quantitating CIC as a means of assessing disease activity or predicting response to treatment and are in contrast to the apparently adverse effect of elevated pretreatment CIC on response to therapy and survival observed in adults with ALL, AML, and OS.  相似文献   
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Sonographic evaluation of caudal spine anomalies in children   总被引:1,自引:0,他引:1  
Retrospective analysis of B-mode spinal sonography in 15 pediatric patients with spinal dysraphism and caudal anomalies documents a high degree of accuracy in identifying the presence, site, size, and configuration of meningoceles; and slightly less accuracy in identifying extension of neural tissue into the meningocele and presence of concurrent lipoma. B-mode sonography is capable of displaying spinal anatomy clearly enough to permit accurate retrospective interpretation of pathologic changes. When radiologists learn to interpret sonographic images well enough to achieve equal accuracy in prospective diagnosis, then B-mode spinal sonography will supplant computed tomography and myelography as the preferred screening procedure in the initial evaluation of children with selected anomalies of the caudal spine.  相似文献   
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Smoking is a high-risk behavior that affects the health and economic welfare of society. Thus, it is important to quantify the economic burden smoking places on social institutions in the United States.
OBJECTIVE: The purpose of this review paper is to analyze smoking cost studies and to provide estimates that represent the economic costs of smoking from different perspectives of society, and as a whole.
METHODS: Current Contents (1996–), Health Star (1970–), and Medline (1966–) databases were searched through the use of pertinent subject headings and key words: tobacco use, smoking, cost, and economics. The internet was utilized to identify potential sources of epidemiological and cost information on smoking. Recent cost-of-illness studies using different methodologies: human capital, incidence, and prevalence were chosen for review based on their relevance.
RESULTS: Preliminary results indicate that the published cost studies available underestimate the "true" costs of smoking. The most current articles approximate annual direct medical costs to health care payers of $50 billion (1993); inflating to 1997 equals $59 billion or $1,200 per smoker. Although the latest cost studies do not attempt to estimate indirect costs, past studies have found indirect costs to be 1.5–2 times the direct costs. Therefore, using direct and indirect costs we estimate total smoking costs to be $150 billion (1993); inflating to 1997 equals $176 billion or $3,500 per smoker.
CONCLUSION: Quantifying the cost of smoking is a difficult task due to tobacco use infiltrating many aspects of life and the dependency of cost on perspective. Cost-of-illness studies provide cost estimation data which can be useful in aiding decision-makers who are allocating health care resources.  相似文献   
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Radiographic cystography (VCUG) has been advocated to detect dynamic and anatomic abnormalities of the lower urinary tract in the neonate with myelomeningocele (MM). We reviewed the VCUG in 120 neonates and the radionuclide cystograms (RNC) or cystometrograms (RNCMG) in 30 neonates to reevaluate the role of cystography in this population. Surgery was not required to treat the anatomic abnormalities detected by VCUG. The absence/presence of reflux and a bladder residual volume of greater than 15 cc were the two most important criteria in determining the neonatal voiding regimen. Because RNC provides this information equally well with a much smaller radiation dose and because of the additional functional information available from RNCMG, we now recommend that RNC or RNCMG be used to evaluate the lower urinary tract of neonates with MM.  相似文献   
29.
Perirenal urinomas may develop when obstruction to urinary flow creates sufficient back pressure to produce extravasation of urine. Such fluid collections have been described as mainly sonolucent. However, in the last 2 years, we have imaged five neonates with multiple, marked septations of the urinoma, four with posterior urethral valves and one with a ureteropelvic junction obstruction. Diagnostic confusion may arise when the kidney is not identified, when the septated nature of the urinoma is not recognized, and when urinary tract obstruction is not seen.  相似文献   
30.
Preliminary repair of the midline thoracic defect in a newborn with ectopia cordis entailed the use of a prosthetic silo and fluid-filled tissue expanders placed under the lateral chest wall. On post-operative radiographs these expanders simulated the appearance of massive subcutaneous oedema of the chest wall.  相似文献   
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