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Ocular trauma is not uncommon. Because the tissues associated with visual function are delicate and remarkably specialized, care of ocular injuries is best left to well-trained specialists. Initial care, however, is often simply common sense. Irrigation of chemical burns, sterile techniques, and procedures that salvage tissue are good general principles.  相似文献   
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The association of sociodemographic and family composition data with obesity was studied in 1213 black and 1166 white girls, ages 9 and 10, enrolled in the National Heart, Lung, and Blood Institute''s Growth and Health Study. Obesity was defined as body mass index at or greater than age- and sex-specific 85th percentile as outlined in the Second National Health and Nutrition Examination Survey. The prevalence of obesity was higher for pubertal girls than for prepubertal girls and for girls with older mothers/female guardians. As odds ratio of 1.14 was observed for each 5-year increase in maternal age. Obesity was less common for girls with more siblings; the odds for obesity decreased by 14% for each additional sibling in the household. In blacks, the prevalence of obesity was not related to parental employment or to parental education. In whites, the odds of obesity were higher for girls with no employed parent/guardian in the household and for girls with parents or guardians with lower levels of educational attainment. Examining the associations between sociodemographic factors and risk of childhood obesity provides important clues for understanding racial differences in obesity, a major risk factor for coronary heart disease.  相似文献   
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Malignant melanoma associated with melanocytoma of the optic disc   总被引:1,自引:0,他引:1  
A 61-year-old white man underwent enucleation because of progressive growth of a pigmented epipapillary tumor that was diagnosed 9 years earlier as an optic nerve and juxtapapillary melanocytoma. Histopathologic studies showed the tumor was a malignant melanoma of the optic disc and juxtapapillary retina and choroid. Foci of typical melanocytoma cells were within the tumor. The tumor produced segmental atrophy of the optic nerve. This is a rare example of a malignant melanoma developing in conjunction with a lesion that possessed typical clinical and histopathologic features of a melanocytoma of the optic disc.  相似文献   
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Background: Sevoflurane undergoes Baralyme- or soda lime-catalyzed degradation in the anesthesia circuit to yield compound A (2-[fluoromethoxy]-1,1,3,3,3-pentafluoro-1-propene), which is nephrotoxic in rats and undergoes metabolism via the cysteine conjugate beta-lyase pathway in those animals. The objective of these experiments was to test the hypothesis that compound A undergoes beta-lyase-dependent metabolism in humans.

Methods: Human volunteers were anesthetized with sevoflurane (1.25 minimum alveolar concentration, 3%, 2 l/min, 8 h) and thereby exposed to compound A. Urine was collected at 24-h intervals for 72 h after anesthesia. Rats, which served as a positive control, were given compound A intraperitoneally, and urine was collected for 24 h afterward. Human and rat urine samples were analyzed by19 F nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry for the presence of compound A metabolites.

Results: Analysis of human and rat urine showed the presence of the compound A metabolites [S-[2-(fluoromethoxy)-1,1,3,3,3-pentafluoropropyl]-N-acetyl-L-cysteine, (E)- and (Z)-S-[2-(fluoromethoxy)-1,3,3,3-tetrafluoro-1-propenyl]-N-acetyl-L-cyst eine, 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid, 3,3,3-trifluorolactic acid, and inorganic fluoride. The presence of 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid and 3,3,3-trifluorolactic acid in human urine was confirmed by gas chromatography-mass spectrometry.  相似文献   

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S H Stern 《Primary care》1988,15(4):809-826
An approach that allows a consistent, thorough evaluation can be recommended by a mnemonic using the words ankle/foot. The maxim about foot and ankle pain is that "the good exam begins at the back and ends at the toe." During this exam, the cutaneous, vascular, and neural systems need careful evaluation. The exam is directed to the region of maximal discomfort where careful palpation should pinpoint the spot of greatest tenderness. Once this region has been localized and signs and symptoms collected, consider the differential diagnosis specific for that area. This will narrow the focus, make the number of potential pain sources manageable, and often provide the answer. When the diagnosis is still unclear, obtain standard x-rays of the area. A directed evaluation to probe the region is appropriate. This can mean a bone scan to detect early avascular necrosis, stress fractures or osteomyelitis; an EMG-NCS to assess the neural circuitry; and special x-ray views, CAT scan, NMR, or arthrogram to uncover the difficult fracture. At this point, fortunately, the primary physician is not alone. The diagnostic dilemma or the difficult management case can be referred for a second opinion or therapeutic assistance to a podiatrist, rheumatologist, or the orthopedist with a special interest in feet.  相似文献   
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The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
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