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1.
目的比较聚合酶链反应-序列特异性引物(PCR-SSP)进行HLA-Ⅰ类A、B抗原位点分型的准确性,并探讨血清学分型错误发生的原因。方法用PCR-SSP以及单克隆抗体血清学分型技术对HLA-A、B分型并比较。结果34例样本PCR-SSP基因分型无假阳性和假阴性出现。PCR-SSP法与血清学比较,血清学检出错误或漏检率分别为HLA-A位点23.5%,B位点26.5%。血清学发生错误或易混淆的抗原有:A2和A68、A32和A33,B5、B60和61。结论PCR-SSP法进行HLA-A、B抗原等位基因分型具有分辨率高、特异性强、重复性好、实验过程简捷快速、分型结果较血清学更加准确可靠的优点。  相似文献   
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Background Dentin-bonding systems contain sensitizing acrylates. They are increasingly used in dentistry, but only few cases of allergy have been encountered. Objective This study reports observations on eleven patients sensitized by acrylates in dentin-bonding compounds. Furthermore, the composition of dentin-bonding products was analysed and compared with the information given in the material safety data sheets. Methods Patch testing was performed to reveal allergic contact dermatitis, and chamber provocation tests to reveal possible respiratory sensitivity. Gas chromatography/mass spectrometry was used to analyse the chemical composition of the bonding products. Results The most common sensitizer in our material of eleven patients was 2-hydroxyethyl methacrylate (2-HEMA). Another putative sensitizer, BIS-GMA, used in dentin adhesives, did not cause sensitization. The typical allergic dermatitis localized to the fingertips (pulpitis). Seven of the eleven patients also developed paresthesia of the fingertips. One patient with positive patch test reactions to (meth)acrylates had pharyngitis hut no skin symptoms. One patient was sensitized because she had been patch tested with too high a concentration (undiluted) of dentin-bonding components. Material safety sheets gave inaccurate or wrong information about the contents. Conclusion Dentin-bonding acrylates are strong sensitizers, and even a single exposure may sensitize.  相似文献   
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环氧乙烷对大鼠DNA损伤机理的研究   总被引:1,自引:0,他引:1  
为探讨环氧乙烷(EtO)对DNA分子水平的损伤作用,采用血红蛋白基因特异性的单引物,对用EtO染毒不同时间的Wistar雄鼠和对照个体的肝、肾、睾丸等组织的DNA进行半随机PCR扩增。结果显示:在吸入染毒(800mg/m3)6~9周条件下,EtO可引起肝、肾、睾丸等组织不同程度的DNA损伤,其中睾丸组织DNA损伤最为严重。  相似文献   
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Abstract: Low and high resolution sequence specific oligonucleotide probe hybridization patterns were used to design an approach to direct sequencing of allele specific amplified cDNA. Several PCR amplifications were used to derive overlapping sequence fragments to define complete first domain sequences for a single allele. This method has been used to characterize three new DRB1 alleles in the DR52 family, DRB1*1115, DRB1* 1117, and DRB1*1319. All three alleles carry polymorphisms previously observed in other DRB alleles and underscore the importance of utilizing a directed sequencing approach for obtaining unambiguous typing results in matching for bone marrow transplantation between unrelated donor and recipient.  相似文献   
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用多引物聚合酶链反应检测鼠疫耶尔森菌   总被引:2,自引:1,他引:2  
目的建立多引物检测鼠疫耶尔森菌(鼠疫菌)的PCR(M-PCR)方法.方法合成4对引物,分别来源于质粒和染色体DNA上F1、pla、Hms、Inv基因,对164株鼠疫菌进行扩增.结果在164株鼠疫菌中,有152株菌4种基因扩增均阳性,仅云南省12株Hms基因扩增为阴性.结论采用M-PCR方法检测鼠疫菌DNA具有较好的敏感性、特异性和稳定性,其可作为检测与鉴别鼠疫菌和疫情监测方面快速诊断的方法.  相似文献   
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Testicular germ cell tumors account for about 1% of all cancers. The incidence of these tumors is increasing and they represent the most common solid malignancies of young men aged 15–40 years with seminoma being one of the most common histotype. Pathogenesis of testicular germ cell tumors remains unknown and, although cryptorchidism is considered the main risk factor, there is evidence of an association with environmental and genetic risk factors. Human papillomaviruses (HPV) are a family of DNA viruses and represent a major risk factor for cervical cancer. In addition, they have been associated with other human non‐malignant and malignant diseases, including breast and head and neck cancer. HPV sequences have been detected throughout the male lower genitourinary tract as well as in seminal fluid and an increased testicular tumorigenesis has been reported in HPV transgenic mice. Aim of this study was to evaluate the potential involvement of HPV in human testicular tumorigenesis. Real‐time PCR employing GP5+/GP6+ consensus HPV primers was used to examine the presence of HPV sequences in a subset of human seminoma (n = 61) and normal testicles (n = 23). None of the specimens tested displayed the presence of HPV DNA. These findings do not support an association between HPV and human seminoma and warrant further studies to assess definitively the role of these viruses in human testicular tumorigenesis. J. Med. Virol. 85:105–109, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
9.
We report a novel human leukocyte antigen (HLA)-B allele, HLA-B*5312. Compared with HLA-B*530101, there is one silent substitution at nucleotide 438 and two non-synonymous substitutions at nucleotides 431 and 440, causing a change of the amino acid sequence (Asn-->Ser at codon 77 and Ile-->Thr at codon 80, respectively) within the Bw4 epitope. In contrast to the published sequences (IMGT/HLA Database, version 2.16.0, January 2007), we found that HLA-B*530101 had a C instead of a T at nucleotide -221, whereas HLA-B*350101 had a C instead of an A at nucleotide 2992. According to our sequencing results, HLA-B*5312 resembles HLA-B*350101 regarding its sequence of the untranslated regions. HLA-B*5312 may have been the result of a double crossing over event during which HLA-B*350101 adopted a Bw4 motif.  相似文献   
10.
FAP59/64, FAP6085/6319, and CUT primer sets were designed for detecting cutaneous HPV and have been used in many clinical and epidemiology studies. The FAP6085/64 primer set was first evaluated in this study and the FAP6085/64 combination was found to be much more sensitive than all three original primer sets by using HPV plasmids as a template. To confirm further the effectiveness of the FAP6085/64 primer set in human DNA templates, 90 palmar exfoliated cell DNA samples were used to detect the cutaneous HPV by both the FAP59/64 and FAP6085/64 primer sets. The overall proportion of HPV detection in those skin samples was 77.8% (70/90) using FAP6085/64, as compared to 55.6% (50/90) using FAP59/64. The FAP6085/64 primer set was also applied in a population based study. The proportion of HPV detection was 73.96% (2076/2807) in skin samples collected from healthy individuals, and a total of 336 different PV types were found. Sixty (17.9%) of them were fully characterized HPV types, 127 (37.8%) were putative HPV types which had been described previously, 149 (44.3%) were novel putative HPV types, and two animal PVs were also detected. These results suggest that the FAP6085/64 primer set was sensitive and effective for detection of cutaneous HPV in healthy skin samples.  相似文献   
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