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11.
M F White R Morris R M Feist C D Witherspoon H A Helms G R John 《Southern medical journal》1989,82(2):151-158
Although an estimated 1 million Americans suffer ocular injuries each year, the setting of injury and its prognostic implications have not been closely examined. Using data compiled by the Eye Injury Registry of Alabama (EIRA) from 514 cases of serious eye injury, we examined the demographics and prognosis of ocular injury by setting of injury. Work-related injuries accounted for only 28% of total injuries, and injuries occurring at home accounted for 27%, followed by situations related to recreation (25%), assault (11%), travel (5%), and "other" (school, unknown, etc) (4%). The poorest initial vision, poorest final vision, and highest rate of enucleation occurred in patients injured by assault, whereas the lowest rate of enucleation and loss of light perception was found in patients who had work-related injuries. Patients in the "other" category had the highest rate of return to 20/100 or better vision. 相似文献
12.
Helms G 《NMR in biomedicine》2000,13(7):398-406
The aim of this work was to study and correct the influence of varying coil load and local B(1) field in single volume MR spectroscopy. A simple, precise, and user-independent way to adjust the transmitter gain has been developed and validated. It is based on a fit of the localized signal to flip angle variation around 90 degrees. This method proved to be robust against B(1) gradients and suitable for in vivo applications. Local B(1) correction was combined with an external reference and decomposition of the volume into CSF and tissue to obtain a comprehensive absolute quantification of tissue water content and metabolite concentrations in human brain. STEAM localized spectra of parietal and insular gray matter and subparietal white matter (n = 11, TE = 30 ms) were analyzed using a linear combination of model spectra (LCModel). Coefficients of variation (CV) between 1.5% and 4% were obtained for the tissue water content (1-2% in a single subject). The CVs of major metabolite concentrations (4-21%) were dominated by the errors of the spectral analysis. The largest B(1) variation in the in vivo experiments (range 30%) was due to changes in coil load. Differences in regional sensitivity due to B(1) inhomogeneity (parietal: 8% and 9%; insular: 16%) were found to be the second largest source of variation. Correction for local B(1) improved standard deviations and intra-subject reproducibility. On average, sensitivity was 9% less in insular than in parietal gray matter. If ignored, significant differences were introduced for water and N-acetyl-aspartate or were obscured for creatine and cholines. Hence, local sensitivity correction proved to be necessary for regional comparison of absolute metabolite concentrations. 相似文献
13.
Rigor and resistance to stretch in vertebrate smooth muscle 总被引:2,自引:0,他引:2
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Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
17.
In the infant on parenteral nutrition, cysteine supplementation has been suggested due to low levels of hepatic cystathionase activity limiting synthesis from methionine. We have examined the plasma concentrations of sulfur amino acids in four groups of post-surgical infants requiring parenteral nutrition receiving (A) a low methionine + cysteine + taurine formula, (B) a high methionine formula (non-steady state), (C) a high methionine formula (steady state), and (D) a high methionine + cysteine formula. Plasma methionine concentrations were above the normal reference range (2.2-4.9 micromol/dL) of normal breast-fed infants in Groups B (15.9 +/- 10.7 micromol/dL) and D (5.7 +/- 1.9 micromol/dL) and at the upper limit for Group C (4.9 +/- 1.7 micromol/dL). Total cysteine/cystine concentrations (normal reference range, 10.2-20.4 micromol/dL) were highest in Groups A (18.9 +/- 3.5 micromol/dL) and D (16.8 +/- 5.3 micromol/dL) that received cysteine HCI supplementation, and lowest in Group B (8.6 +/- 3.7 micromol/dL) that received no cysteine in non-steady state. All plasma free cystine concentrations were below the normal reference range (3.6-6.8 micromol/dL). Plasma taurine concentrations were not significantly different among the four groups and all were within the normal reference range (0.6-16.2 micromol/dL). The strikingly elevated methionine and low total cysteine/cystine values in Group B suggested the existence of a feedback loop of methionine conversion below the level of homocysteine. Equilibrium of methionine and cysteine/cystine plasma concentrations did occur, in time. Parenteral cysteine administration resulted in a greater proportion of plasma free cysteine concentration, but not cystine. The proportion of free to bound cysteine/cystine, as well as the proportion of free cystine to cysteine, was not normal during parenteral nutrition with or without cysteine HCI supplementation. Little benefit in plasma concentrations was derived from cysteine HCI supplementation to a high methionine formulation. 相似文献
18.
Chronic avulsive injury of the deltoid insertion in adolescents: imaging findings in three cases 总被引:1,自引:0,他引:1
The clinical and imaging (magnetic resonance [MR] imaging, radiography, and bone scintigraphy) findings in three adolescent boys with chronic avulsive injury at the deltoid insertion are presented. MR imaging enabled the exclusion of findings suggestive of malignancy and the localization of abnormalities to the deltoid insertion site. Findings included cortical thickening and irregularity of the deltoid tubercle, with or without adjacent soft-tissue edema. 相似文献
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Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1