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71.
Objective To investigate the role of T-helper (Th) and cytotoxic T (Tc) lymphocyte polarization in the pathogenesis of condyloma acuminatum (CA) and its correlation with recurrence. Methods Three-colour immunofluorescent flow cytometry was used to detect the proportion of CD3+ CD8-/IFN-γ+ (Th1),CD3+CD8-/IL-4+ (Th2), CD3+ CD8+/IFN-γ+ (Tel) and CD3+ CD8+/IL-4+ (Tc2) cells in the peripheral blood of CA patients and health controls. Results Compared to health controls, CA patients showed a decreased number of Thl (P < 0.01) and Tcl cells (P < 0.05), as well as a decreased Th1/Th2 and Tc1/Tc2 ratio (P <0.05). Furthermore, in 15 recurrent CA patients the ratio of Th1/Th2 was remarkably decreased (P < 0.01),while the ratio of Tc1/Tc2 had no significant change in comparison with health controls. Conclusion The decrease of Th1 and Tc1 subsets results in relative Th2 and Tc2 predominance, and this tendency is more significant in recurrent CA patients. The Th1 to Th2 and Te1 to Tc2 shifts in CA patients could be responsible for the fact that human papilloma virus (HPV) is hard to be eliminated.  相似文献   
72.
目的探讨醛固酮合成酶(CYB11B2)基因多态性与怀化侗族高血压高发人群原发性高血压(EH)及血脂水平的关系.方法采用聚合酶链反应结合限制性内切酶片段长度多态分析方法(PCR-RFLP)检测89例怀化侗族高血压病人和85例正常人的CYB11B2-344C/T等位基因频率和基因型频率.结果高血压组CYB11B2-344C/T基因型频率(CC 10.1%、CT41.6%、TT 48.3%)和等位基因频率(C 30.9%、T 69.1%)与正常对照组基因型频率(CC 10.3%、CT 27.6%、TT 62.1%)和等位基因频率(C 24.1%、T 75.9%)比较无显著性差异.CC基因型患者与CT TT基因型患者比较,收缩压和舒张压无显著性差异.结论怀化侗族人群EH可能与CYB11B2基因多态性无关.  相似文献   
73.
本文介绍了盲人智能探路手杖的研究.该系统由单片机控制,采用两只超声波传感器的探测模式,对盲人行进路上的路况进行探测和分析,并针对不同的路况发出相应的提示信息,以达到辅助盲人安全行走的目的.  相似文献   
74.
The functional supertype of HLA-A2 was investigated in the presentation of the A*0201-restricted Flu matrix p58-66 peptide to activate recall CD8+ T-cell response. In healthy Northern Chinese, the HLA-A2 supertype was mainly composed of the six alleles, A*0201 (26.4%), A*0206 (12.7%), A*0203 (8.2%), A*0207 (7.3%), A*0210 (1.8%) and A*0205 (0.9%), as analyzed by PCR using sequence specific primer (PCR-SSP) and sequence based typing (SBT). The IFN-gamma release Elispot assay was employed to assess effector CD8+ T cells. In A*0201-bearing individuals, the CD8+ T-cell response was potent when stimulated with autologous CD8- PBMCs. The frequency of the effector CD8+ T cells was 96.6% with the magnitude of effector CD8+ T cells of 225 SFC/5 x 104 CD8+ T cells and the RI of 25.7. In non-A*0201 individuals, the effector CD8+ T cells were minimally detectable while the peptide was presented by the autologous CD8- PBMCs. However, the induction of the response of CD8+ T cells obtained from non-A*0201 individuals was remarkably improved when the peptide was presented by autologous dendritic cells instead of CD8- PBMCs. The HLA-A2 alleles possessing cross-reactivity in the peptide presentation were mainly of A*0206 and non-A*0201 heterozygotes of A*0206 and A*0210. Moreover, A*0206 as the HLA-A2 functional supertype was further confirmed by tetramer assay. In two A*0206+ donors with CD8+ T-cell response to the peptide, the CD8+ T-cell frequency assessed by specific binding of peptide HLA-A*0201 tetramer was 4.62% and 1.66%, respectively. Thus, our results have substantiated the immunological relevance of the HLA-A2 supertype, which may benefit the design of peptide vaccines with the potential to be applicable in broader populations.  相似文献   
75.
We show that it is possible to translate an intensity modulated radiation therapy (IMRT) treatment plan and deliver it as a single arc. This technique is referred to in this paper as aperture modulation arc therapy (AMAT). During this arc, the MLC leaves do not conform to the projection of the target PTV and the machine output of the accelerator has a constant value. Dose was calculated using the CORVUS 4.0 IMRT system, which uses a pencil beam dose algorithm, and treatments were delivered using a Varian 2100C/D Clinac. Results are presented for a head and neck and a prostate case, showing the equivalence of the IMRT and the translated AMAT delivery. For a prostate AMAT delivery, coronal plane film dose for the IMRT and AMAT deliveries agreed within 7.19 +/- 6.62%. For a meningioma the coronal plane dose distributions were similar to a value of 4.6 +/- 6.62%. Dose to the isocentre was measured as being within 2% of the planned value in both cases.  相似文献   
76.
血瘦素遗传度的双生子分析   总被引:4,自引:0,他引:4  
目的 观察遗传因素对血瘦素的影响。方法  5 7对双生子 ,用微卫星 DNA基因扫描和分型技术 ,根据基因型的一致性来鉴别卵性。双生子间异同比较估计遗传和环境的相对效应 ,用放免法测定血清瘦素。结果 异卵双生子 (dizygotic,DZ)瘦素的对内方差大于同卵双生子 (monozygotic,MZ)的对内方差 (P<0 .0 5 ) ,前者为后者的 2倍多。但当校正体重指数 (body mass index,BMI)、性别和血尿酸 (uricacid,UA)后 ,MZ的对内方差接近于 DZ的对内方差。血瘦素的遗传度 8% ,校正 BMI、性别等的影响后血瘦素的遗传度为 0 .18%。血压与瘦素在简单相关分析时相关 (收缩压 r=0 .35 5 ,P<0 .0 0 1;舒张压 r=0 .339,P<0 .0 0 1) ,多元逐步回归分析时仅 BMI、性别和 UA入选方程 (R2 =0 .788,P<0 .0 0 1)。结论 遗传因素对血瘦素影响不大 ,血瘦素主要受环境因素影响。  相似文献   
77.
Cystic fibrosis knockout mice (cftr(-/-)) die prematurely of obstruction of the intestine which may result from accumulation of dehydrated glycoconjugate-containing mucus. We noted an increase in the specific activity of [(14)C]glucosamine-labeled high-molecular weight glycoconjugates, probably mucin, in the lumen of the intestine of cftr(-/-) (homozygous) mice compared to cftr(+/+) (wild-type) and cftr(+/-) (heterozygous) mice and a decrease in the turnover of glycoconjugates of several organs of the cftr(-/-) mice. No difference in the anionic composition of secreted intestinal glycoconjugates was detected and no difference in the amount of mucin 1 (Muc1) was found in the small intestine, colon, pancreas, and lungs of the different genotypes. In addition, the spleen of the cftr(-/-) mice was significantly smaller than that of control mice and the small intestine and colon were, respectively, longer and shorter compared to control mice. These results indicate modified glycoconjugate metabolism in cystic fibrosis knockout mice and morphologic changes to the spleen and intestine where the latter modifications are possibly related to the intestinal malabsorption associated with cystic fibrosis.  相似文献   
78.
"虚拟中国人Ⅰ号"的动脉灌注   总被引:4,自引:0,他引:4  
目的 :在“虚拟中国人Ⅰ号”建模前对其动脉进行灌注填充 ,使其能与静脉区分。方法 :一侧颈总动脉双向插管 ,按 40~ 45ml kg体重的灌注量 ,以 4.0× 10 4 Pa的灌注压力 ,灌注红色填充剂。结果 :共灌入填充剂 2 70 0ml。结论 :为“虚拟中国人I号”赋加了动脉显示特色。  相似文献   
79.
Background: Investigation of haplotype/allele frequency data of Y-STR loci in ethnically diverse populations is essential for forensic reference database construction and genetic application. However, the population genetic characteristics of the Chinese Miao minority from Guizhou Province remain uncharacterised.

Aim: To assess forensic characteristics for 23 Y-Chromosomal STR loci in Guizhou Miao and explore population genetic relationships with geographically neighbouring populations.

Subjects and methods: Twenty-three Y-Chromosomal STRs were genotyped using the Powerplex® Y23 system in 103 unrelated Chinese Miao males from Guizhou Province, southwest China. Haplotypes and forensic parameters were obtained. Population relationships of Guizhou Miao with others were revealed using AMOVA and an MDS plot.

Results: A total of 96 haplotypes were identified with overall haplotype diversity (HD) and discrimination capacity (DC) of 0.9985 and 0.9320, respectively. Genetic differentiation was observed with most of the comparison populations, prominently for Guizhou Shui.

Conclusion: The 23 Y-STR loci were highly polymorphic and discriminating in the Guizhou Miao population and could be used for forensic practice and population genetic studies. Population relationship analysis revealed Guizhou Miao had a close genetic relationship with geographically close Guizhou Gelao, as well as Han majorities derived from different regions.  相似文献   

80.
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