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21.
Molecular analysis of PKU in Ireland   总被引:1,自引:0,他引:1  
Classical phenylketonuria (PKU: McKusick No. 261600) is caused by mutations occurring at the phenylalanine hydroxylase (PAH) locus on chromosome 12 and has a prevalence in Ireland of 1 in 4500. We examined 304 independent alleles from 350 patients for the presence of six mutations and have characterized VNTR alleles within the minisatellite region 3' to the PAH gene in patients carrying the most prevalent mutation. R408W was the most common mutation found, with a relative frequency of 42%. All other mutations had relative frequencies of <10%. VNTR analysis showed that the R408W mutation is associated with the VNTR-8 allele in the Irish population, indicating that R408W is associated with RFLP haplotype 1. This differs from that reported from eastern Europe where R408W is associated with RFLP haplotype 2/VNTR-3; an observation which has led several groups to propose a Balto-Slavic origin for this mutation. These results support the hypothesis of a second, independent founding event for the R408W mutation on an RFLP haplotype 1 VNTR-8 chromsome background in the Irish/Celtic population.  相似文献   
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The rhesus macaque as an animal model for hemophilia B gene therapy   总被引:4,自引:3,他引:1  
Lozier JN  Metzger ME  Donahue RE  Morgan RA 《Blood》1999,93(6):1875-1881
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25.
苗淑杰  孙小容  尔凤君 《中国药房》2005,16(20):1579-1580
目的:建立以高效液相色谱法测定小儿磨积片中橙皮苷含量的方法。方法:色谱柱为SpherisorbC18,流动相为甲醇-冰醋酸-水(25∶4∶71),检测波长为283nm,流速为2·0ml/min,柱温为50℃,灵敏度为0·16AUFS,进样量为20μl。结果:橙皮苷进样量在0·024μg~1·2μg范围内与峰面积积分值呈良好的线性关系(r=0·9999),平均回收率为99·1%(RSD=0·8%)。结论:本方法简便、快捷,灵敏度及准确度高,可为小儿磨积片质量控制提供依据。  相似文献   
26.
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.   相似文献   
27.
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.   相似文献   
28.
目的:了解进展较快的食管和贲门癌前病变的时间,为寻找合适的筛查间隔提供线索.方法:在食管癌高发区河北涉县对40~69岁人群开展重复的内镜筛查.结果:301例重复筛查共观察到40例病情发生进展者,其中7例重度不典型增生中:1例首检为正常,间隔13个月检出重度不典型增生,1例首检为基底细胞增生,间隔7个月检出,4例首检为轻度不典型增生,分别间隔3个月、4个月、4个月、10.5个月检出,1例首检为中度不典型增生,间隔12.5个月检出;6例原位癌及黏膜内癌中:1例首检为轻度不典型增生,间隔48个月检出,2例中度不典型增生分别间隔4个月、13个月检出2例,3例重度不典型增生分别间隔3.5个月、9个月、17.5个月检出;3例浸润性癌中:1例中度不典型增生,间隔50个月检出、2例重度不典型增生间隔14个月和19个月检出.结论:食管和贲门癌前病变的滞留时间变异较大,有必要适当缩短筛查间隔,通过及时复查捕获那些进展较快、多点起源和首检遗漏的癌前病变.  相似文献   
29.
目的:观察静心电针法治疗围绝经期综合征的临床疗效。方法:将符合标准的围绝经期患者60例随机分为治疗组(30例)和对照组(30例)。治疗组给予静心电针法治疗,对照组给予克龄蒙治疗,均治疗3个周期。分别于治疗前、治疗1个月、治疗3个月(即治疗结束)、治疗后3个月及治疗后6个月进行随访,采用改良的Kupperman指数(KI)进行症状评分,并于治疗前、治疗结束各检测1次血清雌二醇(E2)、卵泡刺激素(FSH)、黄体生成激素(LH)。结果:治疗组和对照组的总有效率比较差异无统计学意义(90.00%vs.93.33%,P>0.05)。2组KI评分,治疗后各时间点与治疗前比较差异均有统计学意义(P<0.01),2组之间各时间点差异无统计学意义(P>0.05),2组在治疗期间,KI均有下降,当治疗结束后3个月与6个月时,KI评分稍有上升,对照组上升稍多,但2组之间差异无统计学意义(P>0.05)。2组治疗后,性激素水平均得到改善(P<0.01),但2组之间差异无统计学意义(P>0.05)。结论:静心电针法治疗围绝经期综合征,安全、疗效好,值得推广应用。  相似文献   
30.
Abstract – The occurrence of supra- and subgingival calculus, gingival inflammation, periodontal pockets ( 5 mm) and alveolar bone loss was determined in children (10-19 yr) with Down's syndrome (D-S) and in an aged- and sex-matched control group ( n = 39). Of D-S children ( n = 71), 39 of the patients (mean age 15.5 yr) cooperated in a clinical and roentgenologic examination. Alveolar bone loss was determined around incisors and first molars on intraoral radiographs when the distance between cementoenamel junction (GEJ) to alveolar crest (AC) exceeded 2.0 mm. Alveolar bone loss was diagnosed in 39% of the D-S children compared to 3% in the control group ( P <0.001). Of the total number of sites examined on radiographs the distance from CEJ to AC exceeded 2.0 mm in 8% in the D-S group compared to 0.2% in the control group ( P <0.001). The frequency of sites with alveolar bone loss in D-S children was significantly ( P <0.001) higher around the mandibular incisors compared to first molars. The study shows that early signs of periodontitis are frequently seen in D-S children as early as 11 yr of age and the lesions are first diagnosed in the mandibular anterior region.  相似文献   
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