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The neural cell adhesion molecule L1 is a transmembrane glycoprotein belonging to the immunoglobulin superfamily of cell adhesion molecules (CAMs). Its expression is essential during embryonic development of the nervous system and it is involved in cognitive function and memory. Mutations in the L1CAM gene are responsible for four related L1 disorders; X-linked hydrocephalus/HSAS (H ydrocephalus as a result of S tenosis of the A queduct of S ylvius), MASA (M ental retardation, A phasia, S huffling gait, and A dducted thumbs) syndrome, X-linked complicated spastic paraplegia type I (SPG1) and X-linked A genesis of the C orpus C allosum (ACC). These four disorders represent a clinical spectrum that varies both between and within families. The main clinical features of this spectrum are C orpus callosum hypoplasia, mental R etardation, A dducted thumbs, S pastic paraplegia and H ydrocephalus (CRASH syndrome). Since there is no biochemically assayed disease marker, molecular analysis of the L1CAM gene is the only means of confirming a clinical diagnosis. Most L1CAM mutations reported to date are point mutations (missense, nonsense, splice site) and only a few patients with larger rearrangements have been documented. We have characterised a rare intragenic deletion of the L1CAM gene in a sample of DNA extracted from a chorionic villus biopsy (CVB) performed at 12 weeks' gestation. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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The aim of this study was to develop cost-effective, appropriate solidification technologies for treating hazardous industrial wastes that are currently disposed of in ways that may threaten the quality of local groundwater. One major objective was to use materials other than cement, and preferably materials that are themselves wastes, as the solidification additives, namely using wastes to treat wastes or locally available natural material. This research examines the cement-based and lime-based stabilization/solidification (S/S) techniques applied for waste generated at a metal-plating industry and a dye industry. For the lime-based S/S process the following binder mixtures were used: cement kiln dust/ lime, bentonite/lime and gypsum/lime. For the cement-based S/S process three binder mixtures were used: cement kiln dust/cement, bentonite/cement and gypsum/cement. The leachability of the wastes was evaluated using the toxicity characteristic leaching procedure. The applicability and optimum weight ratio of the binder mixtures were estimated using the unconfined compressive strength test. The optimum ratio mixtures were mixed with waste samples in different ratios and cured for 28 days in order to find the S/S products with the highest strength and lowest leachability at the same time. The results of this work showed that the cement-and lime-based S/S process, using cement kiln dust and bentonite as additives can be effectively used in order to treat industrial waste.  相似文献   
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In the last few decades, agricultural reclamation of sewage sludge has increased in many countries. However, this practice must be adopted under recommended conditions to limit the risks associated with the presence of potential pathogens, including protozoan parasites such as Cryptosporidium. In the present work, we evaluated immunomagnetic separation (IMS) combined with an indirect immunofluorescence assay (IFA) in order to detect Cryptosporidium oocysts in sewage sludge samples obtained from the Municipal Wastewater Treatment Plant (MWTP) operating in the city of Florianópolis, State of Santa Catarina, Brazil. Integrated application of spontaneous sludge sedimentation and centrifugation of the supernatant, purification and concentration of oocysts through immunomagnetic separation as well as detection and quantification by means of indirect immunofluorescence using highly specific monoclonal antibodies, proved to be an effective multiple-analysis tool for monitoring the presence of Cryptosporidium oocysts in urban sewage sludge samples. Among 27 samples collected from MWTP, 20 (74.07%) were positive for Cryptosporidium sp. The efficiency of recovery by using the internal control ColorSeed (Biotechnology Frontiers Inc., Sydney, NSW, Australia) was medially 39.96 +/- 11.20%. Actually, oocysts were recovered from 100% of the positive samples tested and the number of Cryptosporidium oocysts found in the samples ranged from one to four. These results demonstrated a high recovery rate of Cryptosporidium oocysts in sewage sludge samples by using IMS-IFA analysis. In conclusion, such an approach can be applied to monitor the presence of the parasite and to determine the potential contamination of sludge destined for soil application.  相似文献   
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