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Starting from five markers, with a well-defined order from distal to proximal 3p21, nine other markers could be inserted in this 3p21 map. Five were precisely mapped genetically. The other markers were ordered by FISH and/or deletion hybrid mapping. The overall 3p21 order from distal to proximal is as follows: D3S1298-D3S1260-(D3S966, D3S1448 (= D3S1449)-D3S1029-D3S32-D3S643-D3F15S2 -D3S2968-D3S1235-D3S1289-D3S1447-D3S1295.  相似文献   
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OBJECTIVE: Our purpose was to investigate the role of the endothelium in the human uterine arterial response to norepinephrine in the nonpregnant and pregnant states. STUDY DESIGN: Tissue was obtained from six pregnant and six nonpregnant women undergoing cesarean section or hysterectomy. Uterine radial arteries were isolated and subjected to norepinephrine dose-response curves with and without intact endothelium. RESULTS: Responses were obtained over a dose range of 10(-8) to 10(-4) norepinephrine. Initially there was no difference between vessels from pregnant and nonpregnant patients, but removal of the endothelium significantly increased the response in vessels from pregnant women. Addition of nitro-L-arginine methyl ester when the endothelium was intact did not alter the dose-response curves. CONCLUSIONS: In pregnancy human uterine radial arteries are more sensitive to norepinephrine than during the nonpregnant state. This increase is countered by an endothelium-derived relaxing factor. The factor is unlikely to be nitric oxide.  相似文献   
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介绍了一种乳液聚合方法,通过种子乳液聚合,选用合适的聚合单体,探讨了引发剂和乳化剂的品种及用量对聚合反应的影响,最终确定了反应工艺条件,合成了一种丙烯酸酯防钻绒涂层剂。  相似文献   
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We report two siblings, an 11-year-old boy and his 7-year-old sister, referred to us with a diagnosis of muscular dystrophy. The boy presented at 22 months with delay in walking. A very high serum creatine kinase (CK) level and a dystrophic muscle biopsy lead to a diagnosis of Duchenne muscular dystrophy prior to the identification of the dystrophin gene. Two years later his sister presented with similar problems. A diagnosis of limb-girdle muscular dystrophy was made when they were shown to have inherited different X-chromosomes and normal expression of dystrophin and all sarcoglycans. Their conditions remained static. Recently a slowing of the peripheral motor nerve conduction velocities and T2-weighted brain magnetic resonance imaging showed increased signal of the white matter, both of which are features of merosin-deficient congenital muscular dystrophy. Immunolabelling using a C-terminal laminin alpha 2 chain antibody showed a reduction in expression, while labelling with another antibody that recognises a 300-kDa fragment showed a very significant reduction. Mutational analysis of the LAMA2 gene showed two mutations: one was a G-->C point mutation at position -1 of intron 28 acceptor splicing site. This mutation induced activation of a cryptic splice at nucleotide 4429 of exon 29 and partial skipping of this exon, with conservation of the open reading frame. The other was a nonsense mutation due to a C_T transition at position 5525 of the cDNA sequence (exon 37), resulting in a stop codon. These data confirm that mutations of the LAMA2 gene that do not completely disrupt the production of the protein can give rise to phenotypes considerably milder than classical merosin-deficient congenital muscular dystrophy. Partial laminin alpha 2 deficiency should be considered in the differential diagnosis of limb-girdle muscular dystrophy.  相似文献   
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