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991.
白塞氏病相关抗原的重组表达及抗原性初步分析   总被引:1,自引:0,他引:1  
目的:探讨Kinectin的抗原性,为下一步研究Kinectin在白塞氏病中的意义奠定基础。方法:从人Hep2细胞抽提RNA,利用RT—PCR扩增能覆盖Kinectin全长的3个片段,其位置分别相当于氨基酸22—510(kin—5),503-994(kin-M)和920-1346(kin-3)。将扩增的PCR片段克隆到pET42—a( )载体中,诱导表达的融合蛋白用白塞氏病病人血清进行Western blot分析。结果:构建的3个表达Kinectin部分片段载体(pET/kin—5、pET/kin-M和pET/Kin-3)具有正确的阅读框架,DNA测序符合率为99%,能在大肠杆菌中表达相应的肽段。8份阳性血清中,用Western blot分析发现,6份血清与kin-M反应,5份血清与kin-3反应,只有一份血清与kin-5有反应。结论:成功地构建表达覆盖Kinectin全长的3个载体,并初步发现Kinectin的抗原性可能主要位于其中间段和羧基端。  相似文献   
992.
During prenatal life, the ductus arteriosus connects the left pulmonary artery and the descending aorta. Morphometric features (length, external diameter, volume) of the ductus arteriosus in 131 human fetuses (65 males, 66 females) were studied by means of anatomical, digital and statistical methods. Regression analysis was used to investigate the growth of the ductus arteriosus during gestation. The values of the length of the ductus arteriosus ranged from 3.95 mm for the 15 week gestational group to 12.20 mm for the 34th week of gestation. The length of the ductus arteriosus related to fetal age (x) increased according to the linear function y = -3.0726 + 0.4381x. The mean values of the diameter of the ductus arteriosus ranged from 1.34 to 3.49mm for the 15 and 34 week gestational groups, respectively. The growth of the ductus arteriosus diameter followed in accordance with the linear function y = 0.2072 + 0.0935x. The mean values of the ductus arteriosus volume ranged from 5.08 mm3 for the 15 week group to 117.30 mm3 of the 34 week gestation group. The volume growth increased according to the function y = 0.0007x3.3782. Positive correlation coefficients between arterial parameters and fetal age were statistically significant (P < or = 0.01) and reached the following values: r1 = 0.98 for Length, r2 = 0.90 for diameter and r3 = 0.94 for volume. Despite the increase in absolute diameter, the relative diameter of the ductus arteriosus (ductus arteriosus-to-aortic bulb diameter ratio) decreased from 0.80 to 0.48.  相似文献   
993.
Congenital dysmorphic features are prevalent in schizophrenia and may reflect underlying neurodevelopmental abnormalities. A cluster analysis approach delineating patterns of dysmorphic features has been used in genetics to classify individuals into more etiologically homogeneous subgroups. In the present study, this approach was applied to schizophrenia, using a sample with a suspected genetic syndrome as a testable model. Subjects (n = 159) with schizophrenia or schizoaffective disorder were ascertained from chronic patient populations (random, n = 123) or referred with possible 22q11 deletion syndrome (referred, n = 36). All subjects were evaluated for presence or absence of 70 reliably assessed dysmorphic features, which were used in a three‐step cluster analysis. The analysis produced four major clusters with different patterns of dysmorphic features. Significant between–cluster differences were found for rates of 37 dysmorphic features (P < 0.05), median number of dysmorphic features (P = 0.0001), and validating features not used in the cluster analysis: mild mental retardation (P = 0.001) and congenital heart defects (P = 0.002). Two clusters (1 and 4) appeared to represent more developmental subgroups of schizophrenia with elevated rates of dysmorphic features and validating features. Cluster 1 (n = 27) comprised mostly referred subjects. Cluster 4 (n = 18) had a different pattern of dysmorphic features; one subject had a mosaic Turner syndrome variant. Two other clusters had lower rates and patterns of features consistent with those found in previous studies of schizophrenia. Delineating patterns of dysmorphic features may help identify subgroups that could represent neurodevelopmental forms of schizophrenia with more homogeneous origins. © 2001 Wiley‐Liss, Inc.  相似文献   
994.
We have developed a method for quantifying the complexity of activation patterns observed during ventricular fibrillation (VF) that is based on our previously reported methodology for decomposing epicardial mapping data into a set of isolated wavefronts. One-half second datasets are acquired from a 21×24 array of unipolar electrodes (1 mm spacing), and the wavefronts are isolated. A correlation technique is used to compute the similarity between all possible pairs of the isolated wavefronts. From these data, the wavefronts are sorted into clusters, each of which represents a recurring wavefront morphology. We define multiplicity (M) as the number of clusters needed to account for 90% of the total activations in the VF episode.M measures the complexity of the rhythm. In repetitive patterns (e.g., sinus rhythm),M=1, indicating that the same morphology repeatedly activates the mapped region. Typically, in VF,M>1, with larger numbers representing more complex, disorganized patterns. As an example, we computedM at 5, 10, 15, and 20 sec after electrical induction of VF in six pigs.M decreased significantly (p<0.001), suggesting increasing organization during this period.  相似文献   
995.
Mixed aeciospore isolates ofCronartium flaccidum andPeridermium pini were obtained from single-tree infections in Britain, Italy and Greece. The 5.8s ribosomal RNA gene and flanking intergenic transcribed spacer regions ITS 1 and ITS2 were found to be highly similar betweenC. flaccidum andP. pini. Within samples heterogeneity was detected at three nucleotide loci in the ITS1 and at four loci in the ITS2 suggesting that several fungal genotypes may occur at a single infection court. The heterogeneity was confirmed by heteroduplex polymorphism analysis of mixed aeciospore products. RFLP of the ribosomal intergenic spacer region 1 (IGSI) amplified from the same templates indicated limited sequence polymorphism in some copies of this repeated locus. Both the sexual and asexual forms ofC. flaccidum show evidence of sequence polymorphism in two independent, non-coding regions of the ribosomal gene array. Variation appears to be greater in the sexual formC. flaccidum, than in the monoaecious formP. pini.  相似文献   
996.
本文对30年前首次住院经CCMD-2再诊断的203例精神分裂症采用通径分析方法,进行了遗传流行病学对照研究。结果显示精神分裂症的发病与产次、性格、家族史有关。  相似文献   
997.
H1N2新亚型流感病毒神经氨酸酶基因来源的进一步研究   总被引:1,自引:0,他引:1  
对流感病毒H1N2亚型重组株A/哈防/1/88、A/哈防/12/92以及H3N2亚型病毒株A/雅防/2/87、A/京防/57/898和A/粤防/1/92神经氨酸酶(NA)基因核苷酸全序列的测定,进一步弄清了A/哈防/1/88病毒株的NA基因确来自当时人群中流行的H3N2亚型病毒株,很可能是来自A/雅防/2/87类病毒株;而A/哈防/12/92病毒株的NA基因可能是与A/哈防/1/88病毒株的NA基  相似文献   
998.
The homeotic mutationspineless-aristapedia (ss a ) transforms the aristae into second tarsi. Flies with aSS a phenotype also show extremely positive geotaxis as measured in a Hirsch-type geotaxis maze. Other antennal mutants and flies with their aristae amputated do not show such extreme positive geotaxis. Deletion analysis has comapped the geotaxis effect withSS a in band 89C on the third chromosome. Finally, a biometrical analysis has detected additional genes on the X chromosome that also affects geotaxis.This work was supported by a Charles and Johanna Busch Memorial Award to T.R.M. and an Anne B. and James H. Leathem Scholarship Fund Award to P.A.M.Department of Biological Sciences and Bureau of Biological Research, Nelson Biological Laboratories  相似文献   
999.
Germline mutations in breast cancer susceptibility genes, BRCA1 and BRCA2, are responsible for a substantial proportion of high‐risk breast and breast/ovarian cancer families. To characterize the spectrum of BRCA1 and BRCA2 mutations, we screened Czech families with breast/ovarian cancer using the non‐radioactive protein truncation test, heteroduplex analysis and direct sequencing. In a group of 100 high‐risk breast and breast/ovarian cancer families, four novel frame shift mutations were identified in BRCA1 and BRCA2 genes. In BRCA1, two novel frame shift mutations were identified as 3761‐3762delGA and 2616‐2617ins10; in BRCA2, two novel frame shift mutations were identified as 5073‐5074delCT and 6866delC. Furthermore, a novel missense substitution M18K in BRCA1 gene in a breast/ovarian cancer family was identified which lies adjacent just upstream of the most highly conserved C3HC4 RING zinc finger motif. To examine the tertiary structure of the RING zinc finger domain and possible effects of M18K substitution on its stability, we used threading techniques according to the crystal structure of RAG1 dimerization domain of the DNA‐binding protein. © 2000 Wiley‐Liss, Inc.  相似文献   
1000.
Genomic typing of polymorphic loci may be hampered by ambiguous typing results. Moreover, robust methods for simultaneous sequencing of two alleles present in a given sample may be difficult to establish. We used denaturing high-performance liquid chromatography (DHPLC) for physical separation of HLA-A alleles before sequence-based genomic typing (SBT). Physical separation was achieved by resolution of heteroduplexes between the sample alleles and a modified reference probe by DHPLC followed by selective reamplification of the sample alleles present in heteroduplexes. Complementary strands of the reference probe and sample alleles for heteroduplex induction were obtained by lambda-exonuclease digestion. HLA-A genotyping of 101 individuals using DHPLC-SBT yielded better typing resolution compared with serological typing and genotyping by the sequence-specific primer-polymerase chain reaction (SSP-PCR) method. Physical separation of alleles using a modified reference probe allows for development of fully automated methods for genomic typing of highly polymorphic loci such as HLA.  相似文献   
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