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Raj P. Kapur Ian Neilson Robert M.W. Hofstra Lynda W. Holloway Ron C. Michaelis Kathleen A. Leppig 《American journal of medical genetics. Part A》2002,108(1):51-56
Congenital hydrocephalus associated with aqueductal stenosis and/or agenesis of the corpus callosum has been described in newborn males with mutations in L1CAM, a gene that encodes a neural cell adhesion molecule. These males usually have severe mental retardation and may have spastic paraplegia and adducted thumbs. In contrast, Hirschsprung disease, or absence of ganglion cells in the distal gut, has rarely been described in such individuals. We report a male infant who had severe hydrocephalus identified in the prenatal period with evidence of aqueductal stenosis and adducted thumbs at birth. He developed chronic constipation, and rectal biopsy confirmed the diagnosis of Hirschsprung disease. Molecular testing of the L1CAM gene revealed a G2254A mutation, resulting in a V752M amino acid substitution. A common polymorphism in RET, but no mutation, was identified. Our patient represents the third example of coincident hydrocephalus and Hirschsprung disease in an individual with an identified L1CAM mutation. We hypothesize that L1CAM‐mediated cell adhesion may be important for the ability of ganglion cell precursors to populate the gut, and that L1CAM may modify the effects of a Hirschsprung disease–associated gene to cause intestinal aganglionosis. © 2002 Wiley‐Liss, Inc. 相似文献
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Cyclohexanone was condensed with N-hydroxymethyl benzamide in conc. sulphuric acid to give alpha-methyl-benzamido-cyclohexanone (I). The reaction of (I) with thiosemicarbazide in ethanol resulted in alpha-methyl-benzamido-cyclohexanone thiosemicarbazone (II). Condensation of (II) with various aromatic aldehydes in the presence of ethanol afforded alpha-methyl-benzamido-alpha'-substituted-styryl-cyclohexanone thiosemicarbazones (III) in yields ranging from 40 to 50 percent. The compounds exhibited pronounced antiimplantation activity in female albino rats. 相似文献
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This paper studies the thermoluminescence (TL) glow curves of NaCl:Ca(T) phosphors to various doses of 253.7-nm ultraviolet (UV) radiation at room temperature. TLD grade NaCl:Ca(T) material was obtained by crystallization from solution and was subsequently annealed at 750 degrees C for 2 h, followed by sudden quenching. We undertook measurement of the effect of variable UV radiation doses (10(2) to 10(6) J m-2) on the TL behaviour of NaCl:Ca(T) phosphors. It was observed that the phosphor exhibits a dominant peak around 167 degrees C along with a weak peak at lower temperature. The high-temperature peak (Peak II) is found to grow linearly with the increase in UV dose in the range of 10(2) to 10(6) J m-2. Since the nature of the glow curves under the influence of different doses remains more or less identical, it is believed that the phosphor does not undergo radiation damage and displays high intrinsic TL around Peak II. Examination of the system for fundamental dosimetry requirements shows that it can be used in dosimetry work at 253.7 nm. 相似文献
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Transformation of Penicillium chrysogenum using the Aspergillus nidulans amdS gene as a dominant selective marker 总被引:5,自引:0,他引:5
Summary The Aspergillus nidulans acetamidase gene (amdS) has been used to transform Penicillium chrysogenum at low frequency. Several transformants were tested and shown to be mitotically stable. Southern blot analysis indicated that transforming DNA had integrated into the chromosomal DNA, possibly at multiple sites. 相似文献
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Lichen planus pemphigoides. Is it a separate entity? 总被引:1,自引:0,他引:1
R. K. Joshi D. Natukorala A. Abanmi T.Al Awadi 《The British journal of dermatology》1994,130(4):537-538