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111.
目的观察乙型肝炎e抗原(HBeAg)阴性慢性乙型肝炎(CHB)及肝硬化患者的乙型肝炎病毒(HBV)基因型及丙氨酸氨基转移酶(ALT)水平。方法采用酶联免疫吸附法检测62例CHB和41例肝硬化患者HBV标志物和血清ALT水平,用聚合酶链反应法检测其HBV基因型。结果CHB患者中,21 例(33.9%)为HBeAg阴性,41例(66.1%)为HBeAg阳性;肝硬化患者中,28例(68.3%)为HBeAg阴性,13例(31.7%)为HBeAg阳性。CHB患者中,53例(85.5%)为C基因型,9例(14.5%)为B基因型; 肝硬化患者中39例(95.1%)为C基因型,2例(4.9%)为B基因型。HBeAg阴性CHB患者ALT>40 U/L 者的比例低于HBeAg阳性组(分别为47.6%和85.4%),差异有统计学意义(P<0.01)。HBeAg阴性肝硬化患者ALT>40 U/L者的比例低于HBeAg阳性组(分别为64.3%和92.3%)但差异无统计学意义。结论CHB 和肝硬化患者中,HBeAg阴性者的比例较高,此类患者的ALT水平较低,以C基因型占优势。  相似文献   
112.
目的 探讨白介素4(interleukin-4,IL-4)基因的单核苷酸多态性(single nucleotide polymorphisms,SNPs)与皖汉族人群乙型肝炎病毒(hepatitis B virus,HBV)遗传易感性的关系.方法 采用病例对照研究,501位慢性乙型肝炎(chronic hepatitis B,CHB)患者和301位急性自限性HBV感染者分别组成病例组和对照组;采用多重单碱基延伸SNP分型技术(Multiplex SNaPshot),检测两组人群的IL-4基因rs2227284G/T、rs2243283C/G和rs2243288A/G 3个标签SNPs位点的单核苷酸多态性,分析两组间的等位基因频率、单体型频率、基因型是否存在统计学差异.结果 IL-4基因3个多态位点的基因型频率在两组间差异均无统计学意义(均有P>0.05);IL-4基因3个态位点最小等位基因及其频率在两组间差异均无统计学意义(均有P >0.05);4个单体型GCA、TCA、TCG及TGG两组间差异均无统计学意义(均有P>0.05).结论 皖汉族人群中IL-4基因的3个tagSNPs(rs2227284,rs2243283和rs2243288)位点的基因多态性与HBV感染的基因易感性可能无相关性.  相似文献   
113.
Retrospective serologic screening of 1077 serum samples collected from the primitive tribe from north-eastern India in 1963 revealed high prevalence of HBV (15% HBsAg carrier rate) and HCV (7% anti-HCV positivity) and co-circulation of multiple HBV genotypes-A, C, D and G. Full genome sequencing classified all the G-genotype samples as genotype-I. Comparison of genotype-I-HBV full-genome sequences representing 1963 (n = 5, this study) and 2005 (reported earlier) showed identical recombination break-points of genotypes-A/G/C. Genotype-C and genotype-C-fragment of I-genotype circulating in 1963 were distinctly different. The data demonstrates that the recombination events were not recent. Molecular clock analysis predicted existence of genotype-I in this tribe during 1920s.  相似文献   
114.
目的了解合肥市养殖屠宰环节中肉鸡沙门菌的带菌率、血清型分布、抗生素耐药谱分布以及脉冲场凝胶电泳(PFGE)分子分型情况,为合肥市食品安全提供科学的基础数据,为进一步加强合肥市公共卫生安全提供科学依据。方法2010年7—9月对合肥市10家肉鸡养殖场和14家屠宰户分别采用肛拭法和胴体漂洗法采集45份肉鸡活体和45份肉鸡胴体标本,根据GB/T4789.4—2010对沙门菌进行分离、鉴定以及血清学分析;并采用PCR方法进行复核鉴定;对最终确定的阳性菌株使用临床实验室标准化协会(CLSI)推荐的纸片法进行药敏试验;同时采用PFGE方法确定其分子分型。结果在45份肉鸡活体样本中未检出沙门菌;45份肉鸡胴体样本中检出12株沙门菌,检出率为26.7%,经PCR复核检测,所分离的12株沙门菌对invA和hilA基因的携带率均为100%;12株沙门菌分为3种血清型,其中9株为印第安纳沙门菌,2株为鼠伤寒沙门菌,1株为肠炎沙门菌;12株沙门菌对实验中所采用的15种抗生素总耐药以及多重耐药菌株数均为10株;12株沙门菌共分出7种PFGE带型,9株印第安纳沙门菌共分离出5种不同的PFGE带型;同一血清型的沙门菌分子分型结果,基本位于同一大簇中;相同PFGE带型的菌株,耐药谱非常接近。结论合肥市肉鸡胴体沙门菌检出率高,沙门菌的血清型、药敏性以及基因型具有多样性特征,耐药现象严重,相同PFGE带型的菌株,耐药谱非常接近。  相似文献   
115.
目的:了解3种少见α地中海贫血点突变[血红蛋白Constants Spring (Hb CS),血红蛋白Westmead(Hb WS)和血红蛋白Quong Sze(Hb QS)]杂合子与双重杂合子的临床特征。方法:收集135例上述3种α-地中海贫血点突变的杂合子与双重杂合子患者和正常对照男女各20例,进行血常规参数分析、血红蛋白分析、等位基因特异性寡核苷酸探针反向斑点杂交方法(RDB)和多重跨越断裂点聚合酶链反应(PCR)方法检测基因型。结果:杂合子组、Hb CS和Hb WS双重杂合子(αCSα/αWSα)组均无临床表现,但Hb QS杂合子(αQSα/αα)组的红细胞平均体积(MCV)和红细胞平均血红蛋白(MCH)值小于其余杂合子组(P<0.05)。Hb CS和Hb QS双重杂合子(αCSα/αQSα)组有轻微的临床表现,MCV和MCH值低于Hb CS杂合子和Hb WS杂合子组(P<0.05)。结论:Hb CS杂合子组和Hb WS杂合子组表现为静止型地中海贫血,Hb QS杂合子组更接近轻型地中海贫血。双重杂合子表型多样,Hb CS和Hb WS双重杂合子表现接近于静止型地中海贫血,而Hb CS和Hb QS双重杂合子表现类似中间型α地中海贫血(Hb H病),在遗传咨询中需注意。  相似文献   
116.
目的 了解结核性脑膜炎(tuberculous meningitis,TBM)的致病菌在耐药性和基因型方面的相关性.方法 从500例疑似TBM患者脑脊液标本中经MGIT(Mycobacteria growth indicator tube)960培养仪分离培养出25株结核分枝杆菌(Mycobacterium tuberculosis,Mtb),对这25株Mtb分别进行间隔区寡核苷酸分型(Spoligotyping)法基因分型、14种抗结核药物的药物敏感性试验、10个耐药基因测序.结果 20株为北京基因型,占80.0%(20/25);耐多药结核性脑膜炎(MDR TBM)有3株(3/25),都属于北京基因型;测序结果显示inhA、embB、gyrB、eis 基因未发生突变,katG、rpoB、gyrA、rrs-KAN、rpsL、gidB基因发生突变.结论 北京基因型在耐药TBM中所占比例高,尤其是MDR-TBM.耐药TBM临床分离株与相关耐药基因突变有关系.  相似文献   
117.
The objectives of the present study were to investigate eating behavior and growth parameters in Angelman syndrome. We included 39 patients with Angelman syndrome. Twelve cases had a larger Class I deletion, eighteen had a smaller Class II deletion, whereas paternal uniparental disomy (pUPD) or a verified UBE3A mutation were present in five and four cases, respectively. Eating behavior was assessed by a questionnaire. Anthropometric measures were obtained from medical records and compared to Danish reference data. Children with pUPD had significantly larger birth weight and birth length than children carrying a deletion or a UBE3A mutation. We found no difference in birth weight or length in children with Class I or Class II deletions. When maternal birth weight and/or birth weight of siblings were taken into consideration, children with Class I deletion had a lower weight at birth than expected, and the weight continued to be reduced during the investigated initial five years of life. In contrast, children with pUPD showed hyperphagic behavior and their weight increased significantly after the age of two years. Accordingly, their body mass index was significantly increased as compared to children with a deletion. At birth, one child showed microcephaly. At five years of age, microcephaly was observed in half of the deletion cases, but in none of the cases with a UBE3A mutation or pUPD. The apparently normal cranial growth in the UBE3A and pUPD patients should however be regarded as the result of a generally increased growth. Eating behavior, pre- and postnatal growth in children with Angelman syndrome depends on genotype.  相似文献   
118.
Cap myopathy is a rare congenital myopathy characterized by the presence of caps within muscle fibres and caused by mutations in ACTA1, TPM2 or TPM3. Thus far, only three cases with TPM3-related cap myopathy have been described. Here, we report on the first autosomal dominant family with cap myopathy in three-generations, caused by a novel heterozygous mutation in the alpha-tropomyosin-slow-encoding gene (TPM3; exon 4; c.445C>A; p.Leu149Ile). The three patients experienced first symptoms of muscle weakness in childhood and followed a slowly progressive course. They presented generalized hypotrophy and mild muscle weakness, elongated face, high arched palate, micrognathia, scoliosis and respiratory involvement. Intrafamilial variability of skeletal deformities, respiratory involvement and mild cardiac abnormalities was noted. Muscle MRI revealed a recognizable pattern of fatty muscle infiltration and masseter muscle hypertrophy. Subsarcolemmal caps were present in 6–10% of the fibres and immunoreactive with anti-tropomyosin antibodies. We conclude that the MRI-pattern of muscle involvement and the presence of masseter muscle hypertrophy in cap myopathy may guide molecular genetic diagnosis towards a mutation in TPM3. Regular respiratory examinations are important, even if patients have no anamnestic clues. We compare our findings to all cases of cap myopathy with identified mutations (n = 11), thus far reported in the literature.  相似文献   
119.
目的分析云南省异常血红蛋白E(hemoglobin E,Hb E)杂合子及Hb E合并地中海贫血(简称地贫)病例的血液学表型和基因型特征。方法对100例高效液相色谱分析提示为Hb E异常血红蛋白携带病例进行血细胞分析,并用Gap-PCR和PCR-寡核苷酸探针反向斑点杂交法检测α-和β-珠蛋白基因常见突变类型。结果100例疑似Hb E携带的病例,经基因诊断全部检出β-珠蛋白链CD26突变(HBB:c.79G>A),其中Hb E杂合子90例,Hb E合并αα/-α3.7突变7例,Hb E合并αα/--SEA突变2例,1例为Hb E合并-α3.7/-α3.7。Hb E杂合子血液学表型分析结果:Hb A2(26.02±3.64)%,Hb F(1.35±1.25)%,平均红细胞体积(78.83±4.68)fl,平均红细胞血红蛋白含量(26±1.54)pg,平均血红蛋白浓度(329.65±10.73)g/L,血红蛋白(141.08±16.53)g/L;Hb E复合α地贫时,α地贫基因的突变类型不同,血液学表型结果不同。结论云南省Hb E及Hb E合并α地贫的发生率较高,高效液相色谱能够有效检出Hb E,Hb E合并其它α地贫基因突变时,有较大差异的表型变化;仅依靠血液学结果进行产前筛查会造成Hb E漏诊。  相似文献   
120.
《Neurobiology of aging》2014,35(12):2883.e3-2883.e10
Although epidemiological studies suggest that type 2 diabetes mellitus (T2DM) increases the risk of late-onset Alzheimer's disease (LOAD), the biological basis of this relationship is not well understood. The aim of this study was to examine the genetic comorbidity between the 2 disorders and to investigate whether genetic liability to T2DM, estimated by a genotype risk scores based on T2DM associated loci, is associated with increased risk of LOAD. This study was performed in 2 stages. In stage 1, we combined genotypes for the top 15 T2DM-associated polymorphisms drawn from approximately 3000 individuals (1349 cases and 1351 control subjects) with extracted and/or imputed data from 6 genome-wide studies (>10,000 individuals; 4507 cases, 2183 controls, 4989 population controls) to form a genotype risk score and examined if this was associated with increased LOAD risk in a combined meta-analysis. In stage 2, we investigated the association of LOAD with an expanded T2DM score made of 45 well-established variants drawn from the 6 genome-wide studies. Results were combined in a meta-analysis. Both stage 1 and stage 2 T2DM risk scores were not associated with LOAD risk (odds ratio = 0.988; 95% confidence interval, 0.972–1.004; p = 0.144 and odds ratio = 0.993; 95% confidence interval, 0.983–1.003; p = 0.149 per allele, respectively). Contrary to expectation, genotype risk scores based on established T2DM candidates were not associated with increased risk of LOAD. The observed epidemiological associations between T2DM and LOAD could therefore be a consequence of secondary disease processes, pleiotropic mechanisms, and/or common environmental risk factors. Future work should focus on well-characterized longitudinal cohorts with extensive phenotypic and genetic data relevant to both LOAD and T2DM.  相似文献   
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