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In most occasions the Turner's syndrome is diagnosed on the basis of severe growth retardation. But the possibility of an effective treatment of short stature requires earlier a diagnosis. Among the other signs, the importance of ORL signs is underestimated. A group of 30 patients has been analysed to determine their precise extension. The external ears are frequently prominent, low-set and/or posteriorly rotated. Frequency and chronicity of otitis media is highlighted by hypoacousy of the transmission type. The perception pathology is far less common and seems being independent of middle ear pathology. A abnormal development of the 1st branchial arch is likely to explain the auricular pathology in view of the frequently associated anomalies of the palate and the dental articulation. One must clearly consider the diagnosis of Turner syndrome in the case of chronic auricular pathology associated with low linear velocity in a young girl allowing for earlier diagnosis. 相似文献
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Ari M Ferro Jean Kennedy Roger Kjelgren Julie Rieder Scott Perrin 《International journal of phytoremediation》1999,1(1):9-17
A method is described to assess the toxicity of selected volatile organic compounds (VOCs) in poplar trees. The method is illustrated for a specific aqueous mixture of VOCs that contaminates the groundwater at a site for which phytoremediation was being considered. The VOC mixture contained a variety of aromatic compounds, chlorinated aliphatics, and alcohols. Poplar tree cuttings planted in 50-gallon barrels in the greenhouse were watered via subirrigation. The subirrigant contained either a low (42 mg/L), medium (85 mg/L), or high (169 mg/L) dose of the VOC mixture, or water only (experimental control). Phytotoxicity was evaluated by measuring the physiological parameters of stomatal conductance, shoot elongation, and biomass production. Two experiments are briefly described: (1) The poplar tree cuttings were allowed to become established in the barrels and then treated to gradually increasing concentrations of the VOC mixture until the final dose was reached. The objective was to establish a detailed dose-response relationship. (2) The poplar tree cuttings were given the low, medium, or high dose of the VOC mixture immediately after planting. The aim of this experiment was to determine if the VOC mixture would be inhibitory to root development. Phytotoxic effects were not observed in either experiment. 相似文献
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Aspects of community structure and organization are examined in an assemblage offive species of small carnivores (Family Viverridae). Comparative use of the spatial and temporal niches for each species is studied and used to interpret coexistence. The spatial niche segregates the assemblage into three groups, including a three-species mixed-forest group. This mixed-forest group comprises a single-species diurnal branch and a nocturnal branch. Segregation of the nocturnal branch may only be achieved through trophic differences. 相似文献
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