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71.
Multiple opportunistic infections and neoplasms have been described in the AIDS population over the past 20 years. Four cases of AIDS-related hepatic smooth muscle tumors (leiomyomas) have been described, and of these, three were in children. The fourth case was in a single patient with two hepatic lesions. We describe the imaging features of two adult cases with biopsy-proven hepatic leiomyomas. In one of the cases, the gadolinium-enhanced MRI findings are described, which have not previously been reported. Electronic Publication  相似文献   
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73.
Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months.  相似文献   
74.
We evaluated the performance of 116 U.S. drug information centers in responding to specific questions about drugs. The primary measures were correctness of responses and extent of probing for patient data. Questions addressed the effect of ranitidine on blood alcohol concentrations, the potential interaction between didanosine and dapsone, prevention of nonsteroidal antiinflammatory drug (NSAID)-induced peptic ulcers, and use of erythromycin for diabetic gastroparesis. The percentages of centers providing correct overall responses were 70% for the ranitidine question, 90% for the didanosine-dapsone question, 8% for the NSAID question, and 20% for the erythromycin question. For the three patient-specific questions, the percentages of centers eliciting vital patient data were 27% for the didanosine-dapsone question, 86% for the NSAID question, and 5% for the erythromycin question. In providing pharmacotherapy consultations, drug information centers generally failed to obtain pertinent patient data, thereby risking incorrect responses and inappropriate recommendations.  相似文献   
75.
This article uses data from the National Public Health Performance Standards Program to explore how the performance of essential public health services varies across communities and to identify underlying domains of activity that appear to drive variation in performance. Cross-sectional data were used from 315 local public health jurisdictions located within seven states that participated in the Performance Standards Program pilot tests between 1999 and 2001. Results demonstrate that local public health systems vary considerably in the extent to which they perform essential services and meet established performance standards. Factor analysis results indicate that four underlying domains of activity explain much of the variation observed in the individual performance measures, and that achieving performance standards for a single essential public health service often involves more than one underlying domain of activity. The findings suggest that composite measures constructed from the Performance Standards Program can assist public health decision makers in monitoring the performance of public health systems and identifying promising pathways for improving performance.  相似文献   
76.
Age-related postural deficits elicit compensatory mechanisms such as ankle dorsiflexion in the elderly. To gain further insight into this problem, the ability to match an ankle angle during quiet stance was studied in 12 elderly and 12 young subjects. Following an initial single limb angular perturbation presented in the ±4° range, a subject had to return a tilt platform to level, as determined by the nonperturbed limb. Elderly subjects exhibited significant positive (0.9°) over-shoot of the level position, in contrast to young subjects who matched ankle angle with a mean error of −0.1°. The elderly group also exhibited an increase in positioning error for angular displacements in the range between −1 and +1°. The results document age-related postural changes in ankle positioning which might affect postural stability in older adults.  相似文献   
77.
Multiple myeloma: evaluation by CT   总被引:3,自引:0,他引:3  
Schreiman  JS; McLeod  RA; Kyle  RA; Beabout  JW 《Radiology》1985,154(2):483-486
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.  相似文献   
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79.
Cooper  KL; Beabout  JW; McLeod  RA 《Radiology》1985,157(1):15-17
Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.  相似文献   
80.
A simple and specific method for the quantitative determination of cephapirin, a cephalosporin antibacterial, in finished bulk and dosage forms is reported. The method is based on reproducible degradation under controlled conditions to an unidentified species, which is measured spectrophotometrically at 375 nm. The procedure can be performed manually on a short series of samples in about 15 min or can be automated for large runs. Precursors and related substances show minimal interference. The coefficient of variation of the automated system is about 1% within days and 1.3% among days.  相似文献   
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