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排序方式: 共有5602条查询结果,搜索用时 437 毫秒
31.
目的 鉴定一个人类白细胞抗原(human leukocyte antigen,HLA)新等位基因HLA-B*4609.方法 使用序列特异性寡核苷酸PCR技术进行HLA基因分型,发现反应格局异常的可疑新等位基因,应用分子克隆和DNA双向测序技术测定新等位基因的核苷酸序列,并与已知等位基因进行序列比对分析.结果 检出1个样本HLA-B位点反应格局异常,DNA测序分型结果一个为B*151101,另一个的核苷酸序列与已知的HLA等位基因均不同,该基因序列与同源性最高的HLA-B*460101基因序列相比,在第3外显子区域中527位碱基发生A→T突变,导致176位编码氨基酸由谷氨酸(GAG)变成缬氨酸(GTG).结论 样本中含有HLA-B新等位基因序列.该序列申报后,被世界卫生组织HLA因子命名委员会正式命名为HLA-B*4609. 相似文献
32.
New therapies for systemic lupus erythematosus 总被引:2,自引:0,他引:2
In the past 40 years, prognosis for patients with systemic lupus erythematosus (SLE) has improved, with 10-year survival now approximately 90%. This is due probably to a combination of earlier disease diagnosis and diagnosis of milder disease, due in part to availability of multiple serological tests for SLE, use of steroids and other immunosuppressive agents, and availability of renal dialysis and transplantation. Despite this, however, the potential for significant morbidity and mortality remains in the group of patients with partially responsive or treatment resistant disease. More recently, advancements in the understanding of molecular mechanisms involved in the pathogenesis of SLE have translated to the development of novel therapies, offering possible alternatives to this patient cohort. Discussion of these pharmacological options and ongoing research forms the basis of this review. 相似文献
33.
Human isolates of the highly prevalent TT virus (TTV) have been classified into five major genomic groups (1-5). The geographical distribution of the groups throughout the world is not well known. Five different PCR assays were developed in an attempt to amplify specifically TTV DNAs of each genomic group. Serum samples collected from 72 Brazilian adults (24 voluntary blood donors, 24 hepatitis B virus (HBV) carriers, and 24 human immunodeficiency virus type 1 (HIV-1)-infected patients) were tested. TTV DNA from at least one genomic group was detected in 11 (46%) blood donors, 13 (54%) HBV carriers, and 24 (100%) HIV-1 patients. All five genomic groups were detected in the three populations, with the exception of group 2 in blood donors. Some samples, negative with all five specific assays, were positive with the commonly used untranslated region (UTR) PCR system. On the other hand, TTV DNA was detected in some samples by using specific assays but not with the UTR PCR. Mixed infections with 2-5 TTV isolates from different groups were detected in 21% blood donors, 29% HBV carriers, and 71% HIV-1 patients. Fifteen PCR products (three obtained with each assay) were sequenced. Most sequences showed high (>86%) homology with those of TTV isolates belonging to their presumed groups. However, three sequences had low homology with all TTV sequences available from the DNA databanks. In conclusion, TTV isolates belonging to all five known genomic groups circulate in Brazil, and the results suggest the existence of new and as yet uncharacterised major genomic groups. 相似文献
34.
Orazio Gabrielli Anna Ficcadenti Giancarlo Fabrizzi Paolo Perri Antonio Mercuri Giovanni V. Coppa Pierluigi Giorgi 《American journal of medical genetics. Part A》1994,53(3):290-293
We report on a male infant with oral, facial, digital, and skeletal anomalies in association with severe psychomotor delay. This may represent a new oral-facial-digital syndrome. © 1994 Wiley-Liss, Inc. 相似文献
35.
BACKGROUND: The identification of 'unknown' allergic sensitizations may determine the prognosis and treatment of patients with respiratory airway disease. Currently, the presence in homes of 'exotic' animals as pets is increasing. In this article the Siberian hamster or dwarf hamster (Phodopus sungorus) was identified as a new indoor source of aeroallergens and respiratory disease. METHODS: The subjects were six outpatients who were treated for asthma and rhinitis. Siberian hamster hair extract was prepared with a standard wt/vol method, and patients were skin-prick tested with the extract. Serum-specific immunoglobulin (Ig)E against the Siberian hamster, common hamster (Cricetus cricetus) and golden hamster (Mesocricetus auratus) was determined. IgE-immunoblotting was also performed for all six sera. Specific bronchial challenge was carried out with the Siberian hamster extract. RESULTS: Skin prick tests (SPT) with the Siberian hamster extract, and specific IgE-antibodies against Siberian hamster, were strongly positive in all six patients. Determinations of specific IgE-antibodies against C. cricetus and M. auratus were negative in all patients. IgE-immunoblotting of the sera revealed two IgE-binding fractions (MW 18 and 32 kDa) in five of the six sera. Specific bronchial provocation tests resulted in early asthmatic responses in the two patients who were challenged. CONCLUSIONS: The present study reveals the Siberian hamster to be able to induce both sensitization and disease, and this species of hamster should be taken into consideration as a cause of respiratory disease in exposed subjects. A noteworthy finding was the lack of sensitization in our patients to common hamster allergens (M. auratus and C. cricetus) that are usually tested when hamster allergy is suspected. 相似文献
36.
DNA microarray technique for detection and identification of seven flaviviruses pathogenic for man 总被引:2,自引:0,他引:2
Nordström H Falk KI Lindegren G Mouzavi-Jazi M Waldén A Elgh F Nilsson P Lundkvist A 《Journal of medical virology》2005,77(4):528-540
A flavivirus microarray was developed for detection and identification of yellow fever (YF), West Nile, Japanese encephalitis (JE), and the dengue 1-4 viruses, which are causing severe human disease all over the world. The microarray was based on 500-nucleotide probe fragments from five different parts of the seven viral genomes. A low-stringent amplification method targeting the corresponding regions of the viral genomic RNA was developed and combined with hybridization to the microarray for detection and identification. For distinction of the generated virus-specific fluorescence-patterns a fitting analysis procedure was adapted. The method was verified as functional for all seven flaviviruses and the strategy for the amplification, combined with the long probes, provided a high tolerance for smaller genetic variability, most suitable for these rapidly changing RNA viruses. A potentially high detection and identification capacity was proven on diverged strains of West Nile and dengue viruses. The lower limit for detection was equivalent, or better, when compared to routinely used RT-PCR methods. The performance of the method was verified on human patient samples containing dengue viruses, or normal human serum spiked with YF or JE viruses. The results demonstrated the ability of the flavivirus microarray to screen simultaneously a sample for several viruses in parallel, in combination with a good lower limit of detection. 相似文献
37.
In this report, we describe the identification of a human leucocyte antigen-A*11 (HLA-A*11) nucleotide sequence variant, a new HLA-A*1120 by using sequence-based typing (SBT). The new allele was detected during routine HLA typing by high-resolution SBT. Allele A*1120 showed one nucleotide difference with A*110101 at codon 152 (GCG-->GAG) resulting in an amino acid change from alanine to glutamate. Residue 152 is located on alpha(2)-helix of HLA class I molecule and involved in peptide binding by constructing E pocket of peptide-binding groove, implying that the change of the residue 152 would affect the binding affinity of peptides to A*1120 allele. 相似文献
38.
A decline of the Callimico goeldii population in American zoos is presently occurring due to glomerulonephritis of unknown etiology. We hypothesized that this emerging idiopathic fatal renal disease (IFRD) was caused by a virus. We therefore attempted to isolate virus from the kidneys three C. goeldi in Illinois that had IFRD. Along with other viruses, Simian virus 40 (SV-40) strain CAL was isolated. SV-40-CAL is currently the slowest-growing natural isolate of SV-40 in CV-1 cells. Inefficient SV-40-CAL growth in CV-1 cells stems from two features: a suboptimal protoarchetypal regulatory region, and a Large tumor antigen gene sequence like that of SV-40 strain T302, previously considered the slow-growing natural isolate of SV-40. To our knowledge, this is the first documented isolation of SV-40 from a New World monkey outside of a laboratory setting. Though SV-40 is renaltropic, the role of SV-40-CAL in IFRD is uncertain. Transmission of SV-40 to C. goeldii through anthropogenic activity is suspected. 相似文献
39.
Equine herpesvirus type 1 infected cell polypeptides: evidence for immediate early/early/late regulation of viral gene expression 总被引:13,自引:0,他引:13
EHV-1 polypeptide synthesis was examined in productively infected rabbit kidney and hamster embryo cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses of extracts from [35S]methionine- and 3H-amino acid-labeled-infected and mock-infected cultures revealed the presence of 30 infected cell-specific polypeptides (ICPs) which ranged in apparent molecular weights from 16.5K to 213K. Twenty-two of these ICPs comigrated with virion structural proteins. Four ICPs (203K, 176K, 151K, 129K) were detected in extracts of infected cultures labeled in the presence or absence of actinomycin D (Act D) immediately after release from a 4-hr treatment with cycloheximide (CH). These polypeptides, which were designated as EHV-1 immediate early (alpha) ICPs, were not detected in unblocked (non-CH-treated) infected cells. The most abundant ICP was a 31.5K nonstructural protein which, in addition to a 74K protein, was detected in unblocked infected cells at 2-3 hr postinfection. These proteins appeared to be regulated as early (beta) ICPs, since neither protein was observed in Act D-treated cultures released from CH block. Twelve ICPs were classified as late (gamma) polypeptides on the basis of their reduced synthesis in cultures in which viral DNA replication was inhibited by phosphonoacetic acid. All but one (40K) of these late ICPs corresponded to virion structural proteins. 相似文献
40.