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Metabolic diseases of the brain are a rare occurrence. They may be either occurring as inherited diseases causing a destruction of myelin, or they may be the result of toxicity. Neuroimaging, especially magnetic resonance imaging, plays an important role in the detection and classification of these rare diseases. Magnetic resonance spectroscopy is an important tool in the characterization and diagnosis of inherited metabolic diseases.  相似文献   
994.
HSP-70 as a nonspecific early marker in cisplatin ototoxicity   总被引:1,自引:0,他引:1  
CONCLUSION: The great variety of pathological entities related to the presence of circulating HSP-70 suggests a nonspecific cellular damage. As the present study shows, positive results decrease with respect to the time elapsed after the injection of the ototoxic agent. HSP-70 appears as an early and transient marker that could permit early detection of inner ear damage. OBJECTIVES: The aim of this study was to determine the presence of HSP-70 at different time points by means of Western blot immunoassay in the sera of rats treated with cisplatin. MATERIALS AND METHODS: Thirty-six Wistar rats were intraperitoneally injected with cisplatin at a dose of 5 mg/kg and blood samples were collected at 7 and 90 days. Determination of HSP-70 was made by means of a modified Western blot immunoassay kit originally used for human HSP-70 antigen detection. A control group of 18 animals was used for comparison. RESULTS: Western blot was positive in 77.8% of the animals in the 7 days group, decreasing to a 44.4% in the 90 days group. In the control group, Western blot was positive in 5.5%.  相似文献   
995.
Dermoid cysts are congenital lesions composed of tissues with different origins: ectoblastic, mesoblastic, or endoblastic, caused by a defect in the fusion of the embryonic lateral mesenchymatic mass. A true dermoid cyst is a cavity covered with epithelium showing keratinisation and presenting identifiable dermal appendices. We present a case of a male patient aged 53 years presenting tumouration on the floor of the mouth with an evolution of about 30 years. A bibliographic revision of this pathology is also presented.  相似文献   
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We compared the frequency of Pneumocystis in 126 sudden infant death syndrome (SIDS) cases with a control group of 24 infants from the San Diego SIDS/SUDC Research Project who died of accidental or inflicted injuries. Cysts were identified in 33% of SIDS cases and 29% of controls. We conclude that Pneumocystis is not a direct cause of SIDS.  相似文献   
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PURPOSE: To describe a dual-optic accommodating intraocular lens (IOL) based on theoretical considerations. SETTING: University and independent research group. METHODS: Ray-tracing analysis using optical modeling software (ZEMAXTM, Focus Software Inc., Tucson, Ariz) in a theoretical model eye was used to analyze lens configurations to optimize the accommodative and magnification effects of axial lens displacement. Finite-element modelling using a commercially available PC-based software package (COSMOS DesignSTAR) was applied to design the biomechanical parameters of the inter-optic articulations and optics. RESULTS: Ray-tracing analysis indicated that a dual-optic design with a high plus-powered front optic coupled to a minus posterior optic produced greater change in conjugation power of the eye compared to a single-optic intraocular lens and that magnification effects were unlikely to account for improved near vision. Finite-element modelling indicated that the 2 optics can be linked by spring-loaded haptics that allow anterior and posterior axial displacement of the front optic in response to changes in ciliary body tone and capsular tension. CONCLUSION: A dual-optic design linked by spring haptics increases the accommodative effect of axial optic displacement with minimal magnification effect and has promise for improving the performance of accommodative intraocular lenses.  相似文献   
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