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41.
Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms.  相似文献   
42.
A multiple Robertsonian fission chromosomal race of the Liolaemus monticola complex in Chile is described and is shown to be the most derived and the most complex among the Liolaemus examined thus far. The 29 karyotyped lizards analysed from the locality of Mina Hierro Viejo, Petorca, Provincia de ValparaUso, Chile, exhibited a diploid chromosomal number ranging from 42 to 44, and several polymorphisms. The polymorphisms included: a pair 1 fission; a pair 2 fission plus a pericentric inversion in one of the fission products, which moved the NOR and satellite from the tip of the long arm of the metacentric 2 to the short arm of the fission product; a fission in pair 3; a polymorphism for an enlarged chromosome pair 6; and a polymorphism for a pericentric inversion in pair 7. This population is fixed for a fission of chromosome pair 4. A total of 76% of the lizards analysed were polymorphic for one or more pairs of chromosomes. We have compared these data with other Liolaemus monticola chromosomal races and calculated the Hardy–Weinberg ratios for the polymorphic chromosome pairs in this Multiple-Fission race. Karyotypic differences between the Northern (2n = 38–40) and the Multiple-Fission (2n = 42–44) races were attributed mainly to Robertsonian fissions, an enlarged chromosome and pericentric inversions involving the macrochromosomes and one microchromosome pair.  相似文献   
43.
BACKGROUND.: There is agreement that a family history of hypertension (HT),is a predictor for the risk of diabetic nephropathy (DN) inpatients with type 2 diabetes, and possibly also type 1 diabetes.It follows that genes related to the risk of hypertension mustalso be considered candidate genes for DN. The 235T allele ofthe angiotensinogen gene was found to be related to primaryHT. METHODS.: To examine whether it is predictive for DN as well, we examinedthe angiotensinogen gene polymorphism in 230 healthy local controls,423 patients with type 1 diabetes (n=180 with DN; n=243 withoutDN) and 663 patients with type 2 diabetes (n=310 with DN; n=353without DN). The angiotensinogen gene M235T polymorphism wasdetermined using PCR amplification. RESULTS.: The following results were obtained (i) no significant differenceof genotype distribution (type 1: MM/MT/TT(%) 27.6/57.2/15.2vs. 27.2/56.1/16.7 (P=0.92); type 2: MM/MT/TT (%) 31.7/48.2/20.1vs. 32.9/46.8/20.3 (P=0.93)) or allele frequencies (type 1:M 0.56 vs. 0.55 (P=0.795); type 2: M 0.56 vs. 0.56 (P=0.86))was found, between diabetic patients with or without DN, (ii)no difference was found between normotensive and hypertensivediabetic patients. CONCLUSION.: The data argue against a role of the angiotensinogen gene M235Tpolymorphism in the manifestation of diabetic nephropathy orhypertension in diabetic patients.  相似文献   
44.
卡马西平多晶型的研究   总被引:4,自引:0,他引:4  
红外吸收图谱与中国药典图谱不符合的卡马西平(A晶),可通过用较高浓度乙醇使其转为B晶而符合规定,经 ̄(13)CNMR、MS、X线衍射分拆,证实该两种晶体为同质异晶。  相似文献   
45.
目的 通过检测健康志愿者的羧酸酯酶1 (carboxylesterase 1,CES1)和羧酸酯酶2 (carboxylesterase 2,CES2)的基因多态性和基因表达水平,探索CES1和CES2在代谢中的作用。方法 从48例健康志愿者获得血样并提取DNA,对DNA进行二代基因测序,并提取总RNA检测基因表达量。使用多元线性回归分析CES1和CES2基因表达量与性别、年龄、体质量指数(body mass index, BMI)的关系。结果 CES1的基因表达量为141.8(72.7,237.8),CES2的基因表达量为74.4(30.8,133.6)。多元线性回归分析中,BMI与CES2的基因表达有关,性别、年龄和BMI与CES1的基因表达无关。发现CES1 20个基因变异,其中10个会引起氨基酸序列改变;发现CES2 6个基因变异,其中2个引起氨基酸序列改变。结论 发现CES2的表达水平与BMI相关,CES1的表达水平与BMI无明显相关,基因预测结果提示CES1的遗传变异可能影响其功能表达。  相似文献   
46.
王舟  邓金龙  吴东峰 《中国全科医学》2023,26(21):2620-2625
背景 既往研究显示ACAT-1 rs1044925单核苷酸多态性(SNP)与冠心病及缺血性脑卒中的发病风险相关,并且与血脂水平有关。目的 本研究旨在探讨ACAT-1 rs1044925 SNP与急性冠脉综合征(ACS)的关系,以及rs1044925 SNP与ACS患者阿托伐他汀治疗后调脂效果的关系。方法 选择2016年1月—2018年1月在广西壮族自治区人民医院老年心血管内科确诊为ACS并接受经皮冠状动脉介入治疗(PCI)的患者111例作为ACS组(男67例,女44例);患者均接受阿托伐他汀治疗,20 mg/晚;同时服用氯吡格雷75 mg,1次/d(或替格瑞洛90 mg,2次/d),阿司匹林100 mg,1次/d;并在经PCI后常规使用阿托伐他汀,20 mg/晚。对照组为同期体检健康人群,共338例(男170例,女168例)。通过聚合酶链反应和限制性片段长度多态性(PCR-RFLP)对ACAT-1 rs1044925 SNP进行基因分型,检测ACS组和对照组的基线血脂水平,随访检测ACS组患者阿托伐他汀治疗1年后血脂参数。结果 ACS组和对照组受检者的血清总胆固醇(TC)间差异无统计学...  相似文献   
47.
目的 探讨中国江苏地区汉族人群肿瘤坏死因子 β遗传多态性分布。方法 收集江苏地区 16 8名无血缘关系健康个体的静脉血提取DNA ,应用聚合酶链反应限制性片段长度多态性 (PCR -RFLP) ,对TNFβ基因多态性进行分析。结果 TNFβ检测到三个等位基因 ,其基因型频率分别为TNFβ 1/ 1=2 1 4 % ,TNFβ 1/ 2 =4 7% ,TNFβ 2 / 2 =31 5 % ,基因型分布符合Hardy-Weinberg定律。统计分析显示 :江苏地区汉族人群TNFβ等位基因频率分布与欧美白种人均有显著性差异(P <0 0 5 )。结论 TNFβ等位基因频率分布具有种族差异  相似文献   
48.
49.
Three patients with Ehlers-Danlos syndrome type IV (EDS IV) and biochemical evidence of structural defects in collagen III were investigated for mutations within the collagen III gene ( COL3A1 ). Single strand conformation polymorphism analysis of α1(III) cDNA indicated the presence of different heterozygous sequence changes in each of the patients. Nucleotide sequencing revealed mutations leading to the substitution of glycine 400 with glutamic acid, glycine 595 with cysteine, and glycine 1003 with aspartic acid. EDS IV is a life-threatening disorder which, as the clinical histories of our patients and their families show, still often escapes diagnosis. Biochemical and molecular studies can clarify the diagnosis and help provide appropriate management and counselling.  相似文献   
50.
Calcitonin (CT), a calcium-regulating hormone, lowers the calcium level in serum by inhibiting bone resorption. Because CT may play a role in the pathogenesis of osteoporosis, genetic variations in or adjacent to the CT gene may be associated with variations in bone mineral density (BMD). The present study examined the correlation between a dinucleotide (cytosine-adenine; CA) repeat polymorphism at the CT locus and BMD in 311 Japanese postmenopausal women (mean age, 64.1 years). Seven alleles were present in this population; each allele contained 10, 11, 16, 17, 18, 19, or 20 CA repeats. Thus, we designated the respective genotypes A10, A11, A16, A17, A18, A19, and A20. The A10 and A17 alleles were the predominant alleles in the population studied. Z scores (a parameter representing deviation from the age-specific weight-adjusted average BMD) were compared between individuals that possessed one or two alleles of each genotype and those that did not possess the allele. Subjects who possessed one or two A10 alleles had lower BMD Z scores than those who did not (lumbar 2–4 BMD Z score; −0.148 ± 1.23 vs 0.182 ± 1.54; P = 0.04). No significant relationships were observed between allelic status and background data or biochemical parameters. The significant association observed between BMD and genetic variations at the CT locus implies that polymorphism at this locus may be a useful marker for the genetic study of osteoporosis. Received: August 10, 2000 / Accepted: September 6, 2000  相似文献   
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