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H Barry Collin 《Clinical & experimental optometry》2007,90(6):399-400
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A case report is presented in which a patient's initial complaint is of blurred vision after exercise (Uhthoffs symptom). Visual acuity and colour vision were found to be reduced after exercise. Additional neurological signs included homonymous scotomata and delayed visual evoked and somatosensory responses. Magnetic resonance imaging demonstrated multiple abnormal lesions in the brain. The significance of this symptom and its relationship to multiple sclerosis are discussed. 相似文献
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Seventeen patients with ptosis as a feature of chronic progressive external ophthalmoplegia were managed in accordance with a new protocol. An anterior approach levator advancement was performed on seven patients (13 lids) with more than 4 mm of levator function and a brow suspension procedure on eight patients (14 lids) with minimal levator function, in whom the frontalis muscle was relatively spared. Ptosis props were prescribed for two patients with a very weak orbicularis and poor lid closure. Six patients required long term lubricants, and one developed a postoperative corneal abscess associated with a poor Bell's phenomenon. Satisfactory elevation of the lids was achieved in 16 patients (25 lids). 相似文献
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J Bouyer J Dreyfus P Lazar D Collin G Winisdoerffer E Papiernik 《Revue d'épidémiologie et de santé publique》1988,36(2):83-88
A preterm birth prevention program was instituted in France in the early 1970s. Its effectiveness has been assessed through a perinatal study in Haguenau. A relationship between prenatal care improvement and preterm birth rate decrease was noted, but a causal interpretation cannot be derived from such an observational study. However, some arguments do support this interpretation: no satisfactory alternative explanation (such as biases in pregnancy duration measurement, change in the composition of the population of pregnant women, or secular trend), a plausible causal pattern, and a dose-response relationship between prenatal care and preterm birth rate. The Haguenau study results can be applied to other French regions, but extrapolation to other countries would depend on their social, medical and cultural contexts. 相似文献
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Retinal topography in reef teleosts. II. Some species with prominent horizontal streaks and high-density areae 总被引:2,自引:0,他引:2
The retinal ganglion cell layer of five species of reef teleosts was studied from Nissl-stained whole-mounts and the distribution of neural elements determined quantitatively. Iso-density contour maps of neurons in the ganglion cell layer revealed a temporal area centralis (ranging from 3.5 to 8.3 x 10(4) cells/mm2) which often extended into a horizontal streak (ranging from 1.4 to 5.0 x 10(4) cells/mm2) across the retinal meridian. Species possessing a marked horizontal streak were found to inhabit open water and perceive their environment with an uninterrupted view of sand-water horizon. The behavioural significance of these horizontal areas of acute vision is also discussed. 相似文献
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The volume-deficient orbit: clinical characteristics, surgical management, and results after extraperiorbital implantation of Silastic block. 总被引:2,自引:2,他引:0
The surgical techniques and results after extraperiorbital implantation of Silastic on the orbital floor of 70 patients are reviewed. In 11 patients the implant was through a subciliary approach and in 59 through an inferolateral cantholysis. The inferolateral cantholysis, a simplification of the McCord and Moses approach to the orbital floor, is particularly suited to this application. The implanted Silastic was retained in 66 patients, with an average follow up of 3.5 years (range less than 1 to 9.5 years), though six required surgery to debulk the anterior end of the implant. Further surgery was required in 27 patients, this generally being to correct the position of either the upper or the lower lid. Volume enhancement was effective in most cases, there being a significant reduction in the degree of recession of the prosthesis and the depth of the unsightly sunken sulci of the upper and lower lids. The mobility of the orbital contents, the prosthesis, and the upper lid was not improved. 相似文献
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One hundred and eighty-three surgical procedures were conducted on 107 patients over seven years. 91% of the cases of upper lid entropion were corrected satisfactorily with only one operation. It is postulated that this level of success is achieved by grading the degree of surgical intervention according to the clinical established on systematic examination of upper lid entropion. 相似文献
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