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J W McLaren S D Trocme S Relf R F Brubaker 《Investigative ophthalmology & visual science》1990,31(2):339-346
Measurement of light scattered in the anterior chamber can provide important clinical information about the eye. In this study, a scanning ocular spectrofluorophotometer was used to measure scattering in the anterior chamber. Pathologic scattering (flare) was induced by argon laser photocoagulation of the iris in pigmented rabbits. The spectrally corrected intensity of the flare in inflamed eyes decreased as the inverse 2.2 power of the wavelength of the illuminating beam. The strongest signal with this instrument was measured at 470 nm. Diurnal variation of normal and spontaneous scatter from the aqueous humor was measured in nine pigmented rabbits entrained to a 12-hr light/12-hr dark cycle and in eight human subjects. A technique is described for determining the rate of flow of aqueous humor from scattered light when the transfer rate of scattering substance into the anterior chamber is constant. This technique was used to study changes in flow over the diurnal cycle. The rate of flow in human subjects during sleep was 60% of the rate during waking hours. In rabbits, the rate was lowest (44% of maximum) during the 6 hr after the lights were turned on, and were greatest just before the lights were turned on. These findings confirm previous studies of the circadian rhythm of aqueous humor flow in rabbits and humans. 相似文献
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目的 探讨创伤后迟发性脑肿胀的临床特点、发病机制与治疗。方法 回顾性分析1998年1月~2005年6月年收治的17例迟发性脑肿胀患者的临床特点和救治情况。结果 所有颅脑损伤患者采用保守治疗后均有好转,但于伤后5-10d出现恶化,CT复查有脑肿胀,经加强综合脱水等治疗后16例治愈,1例死亡。结论 迟发性脑肿胀好发于对冲性额、颞叶挫裂伤伴明显蛛网膜下腔出血、硬膜下薄层血肿及早期CT有脑肿胀者。其发病机制可能与创伤后的迟发性脑血管痉挛、微循环障碍、静脉回流障碍及甘露醇作用下降等因素有关。此类患者病情隐蔽性强,应加强观察、积极行CT复查,如能早期明确诊断,保守治疗多数效果良好。 相似文献
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F E Brenner G G Bond E A McLaren S Green R R Cook 《Occupational and environmental medicine》1989,46(2):133-137
The prevalence of selected illnesses and symptoms during 1977-85 was compared between 175 employees potentially exposed to the organophosphate insecticide chlorpyrifos and 335 matched controls with no history of exposure to organophosphates. Subjects were subdivided into three exposure intensity groups on the basis of job title and air monitoring data for dose response testing. This classification scheme was shown roughly to correlate with plasma cholinesterase inhibition in the workers. No statistically significant differences in illness or prevalence of symptoms were observed between the exposed and unexposed groups or among the three exposure subgroups. Potentially exposed employees did report symptoms of dizziness and of malaise and fatigue relatively more often than subjects from the comparison group; however, further analyses by exposure level, process area, or time did not support a relation with exposure. No cases of peripheral neuropathy were seen among the exposed workers. Although the sample size was small and the statistical power limited, the cumulative exposures likely to have been experienced by this workforce exceed those to be expected for individuals using the product as recommended. The absence of exposure related adverse effects, including neurological impairment, is reassuring. 相似文献
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A synchronous occurrence of large bowel adenocarcinoma and extragenital malignant mixed mesodermal tumour (MMMT) is reported. This case represents the sixth extragenital MMMT reported in the literature. 相似文献
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Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
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