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Journal of Neurology - Alien limb syndrome following stroke within the territory of the posterior cerebral artery is exceedingly rare. A right-handed female experienced left homonymous hemianopia,...  相似文献   
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PurposeAbout half of pediatric blunt trauma patients undergo an abdominopelvic computed tomographic (CT) scan, while few of these require intervention for an intraabdominal injury. We evaluated the effectiveness of an evidence-based guideline for blunt abdominal trauma at a Level I pediatric trauma center.MethodsPediatric blunt trauma patients (n = 998) age 0–15 years who presented from the injury scene were evaluated over a 10 year period. After five years, we implemented our guideline in which the decision for CT was standardized based on mental status, abdominal examination, and laboratory results (alanine aminotransferase, aspartate aminotransferase, hemoglobin, urinalysis).ResultsThere were no differences in age, GCS, SIPA or ISS scores between the patients before or after guideline implementation. Nearly half of the patients (48.3%) underwent CT scan before guideline implementation compared to 36.7% after (p < 0.0002). There was no difference in ISS (p = 0.44) between CT scanned patients in either group. No statistical differences were found in rate of intervention (p = 0.20), length of stay (p = 0.65), or readmission rate (0.2%) before versus after guideline implementation. There were no missed injuries.ConclusionImplementation of an evidence-based clinical guideline for pediatric patients with blunt abdominal trauma decreases the rate of CT utilization while accurately identifying significant injuries.Level of evidenceIII.  相似文献   
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The objective of this study was to determine experimentally the sex-specific correlation of femoral and lumbar DXA and calcaneal ultrasound, measured in situ, with the in vitro failure loads of the proximal femur. Fifty-eight cadavers with intact skin and soft tissues (34 male, aged 81.2 ± 8.7 years; 24 female, aged 83.7 ± 10.6 years) were examined. The bone mass of the proximal femur and the lumbar spine were determined using dual-energy X-ray absorptiometry and the ultrasonic properties of the calcaneus with quantitative ultrasound. Afterwards, the right femora were excised 18 cm distal to the minor trochanter, and their load to failure determined with a material testing machine. Femoral fracture loads were significantly higher in males than in females, both before and after correcting for body height and weight. Femoral neck bone mineral density (BMD) was significantly correlated with femoral failure loads (r= 0.65 all specimens, 0.57 males (0.64 after excluding trochanteric fractures) and 0.77 females; p <0.001). The correlations with the ultrasonic Stiffness Index of the calcaneus were in a similar range (r= 0.67 all specimens, 0.48 males (0.64 after excluding trochanteric fractures) and 0.65 females; p <0.001). The correlations between femoral failure loads and the spinal BMD were lower (r= 0.40, p <0.01), particularly in males (r= 0.30, not significant). In contrast to previous experimental investigations on excised bones, our results are consistent with clinical studies that have reported that ultrasound and femoral DXA have a similar ability to predict the risk of hip fracture. Received: 13 November 1997 / Revised: 4 March 1998  相似文献   
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Monitoring human tumor response to therapy by means of P-31 MR spectroscopy   总被引:1,自引:0,他引:1  
Tumors in 23 patients were studied by means of in vivo phosphorus-31 magnetic resonance (MR) spectroscopy. In five patients, the response to chemotherapy and radiation therapy was monitored in a long-term follow-up study. In one patient, the P-31 MR spectra were recorded during the infusion of chemotherapeutic drugs. In comparison with healthy muscle tissue of patients, the tumors showed elevated inorganic phosphate, phosphomonoester, and phosphodiester peaks and reduced creatine phosphate peaks, whereas the nucleoside 5'-triphosphate levels remained nearly unchanged. Tumor treatment resulted in changes in the ratio of the signal intensity value of creatine phosphate to that of inorganic phosphate and in the sum of these values. In an osteosarcoma, an initial response followed by renewed tumor growth was clearly indicated by changes in these parameters. In the short-term follow-up examination, slight spectral changes were observed during the infusion of chemotherapeutic drugs. Changes in the concentrations of phosphorus metabolites during therapy can therefore be monitored in human tumors by means of P-31 MR spectroscopy.  相似文献   
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Three new pyrone glucosidic derivatives, together with the known pyromeconic acid glucoside, three acytelenes and two eudesmanes, were obtained from the aerial parts of Conyza albida. The structures were elucidated by high field NMR spectroscopy.  相似文献   
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