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71.
乙型肝炎患者血清中分泌型IgA水平与HBV DNA含量的关系   总被引:1,自引:0,他引:1  
湖北省鹤峰县人民医院检验科,鹤峰 445800目的 研究乙型肝炎患者血清中分泌型IgA(SIgA)水平与乙型肝炎病毒(HBV)DNA含量的关系,为临床提供一个新的评价HBV复制状态及肝细胞损伤的指标。方法 100份经ELISA检测并确诊为乙型肝炎的患者血清用荧光定量PCR检测HBV DNA的拷贝数,用ELISA并经酶标仪定量其SIgA的量。结果 SIgA的含量与HBVDNA的拷贝数的对数呈正相关(r=0.69,P<0.01),在HBsAg( )/HBeAg( )/HBcAb( )组和HBsAg( )/HBeAb( )/HBcAb( )组中SIgA含量差异无显著性意义(P>0.05),而HBV DNA拷贝数前者明显高于后者(P<0.01)。结论 乙型肝炎患者血清SIgA的含量在评价HBV的传染性及肝细胞损伤程度方面比乙型肝炎血清学标志物(HBV-M)更灵敏、准确。  相似文献   
72.
林敏  张仁利  高世同 《热带医学杂志》2004,4(3):253-254,267
目的 体外扩增间日疟原虫深圳株红内期小亚单位核糖体核糖核酸编码基因(SSUrDNA)片段,研究其结构与功能。方法 设计一对特异性引物,采用聚合酶链反应(PCR)从间日疟原虫患者血样中扩增出间日疟原虫SSUrDNA片段,以PUC19质粒T载体构建重组子导入大肠杆菌JM109;阳性克隆双酶切鉴定后,双脱氧末端终止法测定序列。结果 间日疟原虫SSUrDNA扩增片段大小为341bp;阳性克隆双酶切及PCR扩增均得到预期大小的片段;序列测定插入片段为341bp,与Sal I株顺序相比,仅在第151位处缺失一个碱基C。结论 成功克隆了间日疟原虫SSUrDNA片段.该序列在间日疟原虫虫株间高度保守。  相似文献   
73.
人发角蛋白桥接周围神经缺损的形态学观察   总被引:2,自引:1,他引:1  
目的 :了解人发角蛋白在神经再生中的作用 ,为临床桥接周围神经缺损寻求新的替代材料。方法 :将 18只新西兰兔的双侧坐骨神经切断 ,造成 10mm缺损 ,一侧用人发角蛋白桥接 (实验组 ) ,另一侧用空硅胶管桥接 (对照组 ) ,术后 1、 2、 3个月通过肉眼观察 ,光镜、电镜和有髓神经密度测定 ,观察、分析神经再生情况。结果 :实验组再生神经均通过 10mm缺损 ,对照组有 2例无神经生长 ;实验组再生神经排列较紧密、有序 ,髓鞘形成早于对照组 ;神经纤维密度明显高于对照组 (P <0 0 1)。结论 :人发角蛋白可促进周围神经再生 ,是桥接周围神经缺损的理想材料。  相似文献   
74.
BACKGROUND: The hamster cheek-pouch carcinogenesis model is a well-known animal system that closely mimics the development of premalignant and malignant lesions in human oral cancer. Our aim was to numerically characterize the premalignant and malignant lesions and expressions of field cancerization in this model using ploidy as the end-point. METHODS: To study the DNA content and proliferation status of the cells in this model we assessed the Feulgen reaction and the immunohistochemical reaction for 5-bromo-2-deoxiuridine (BrdU) in different histological areas of serial tissue sections of the cheek pouches of animals injected with BrdU. RESULTS: Ploidy values were higher in cancerized epithelia with no unusual microscopic features (NUMF), in preneoplastic and tumor areas than in control epithelia. The aneuploidy index was higher in NUMF areas than in control and differed significantly from control in preneoplastic areas and carcinoma. CONCLUSIONS: The unexpected alteration in DNA content observed in NUMF epithelia is of great relevance as a biomarker of field cancerized areas.  相似文献   
75.
树舌多糖GF对小鼠HepA瘤基因组DNA甲基化影响的实验研究   总被引:2,自引:0,他引:2  
目的初步探讨树舌多糖GF对小鼠HepA瘤基因组甲基化的影响.方法提取基因组DNA,采用限制性酶切片段长度多态性分析的方法进行甲基化检测.结果 HpaII酶切结果:树舌多糖组可见3个条带,猪苓对照组可见3个条带, 阴性对照组可见4个条带,正常对照组可见2个条带.MspI酶切结果:树舌多糖组可见6个条带,猪苓对照组可见5个条带,阴性对照组可见5个条带,正常对照组可见6个条带.结论小鼠HepA瘤基因组DNA是低甲基化的,树舌多糖GF有阻碍小鼠HepA瘤基因组DNA低甲基化发生的趋势,可能还具有抗5mC的突变的作用.  相似文献   
76.
ReProComet: a new in vitro method to assess DNA damage in mammalian sperm.   总被引:1,自引:0,他引:1  
The increasing request of chemical safety assessment demands for the validation of alternative methods to reduce the resort to animal experimentation. Methods that evaluate reproductive toxicity are among those requiring the largest use of animals. Presently, no validated in vitro alternative exists for the assessment of reproductive toxicity. Mammalian sperm are sensitive targets of DNA-reactive chemicals, which form premutagenic adducts. Here, we propose a new method based on comet assay to detect DNA damage induced by potential germ cell mutagens in bull sperm available from assisted reproduction practices. In somatic cells, chemical-induced adducts can be revealed by comet assay that detects DNA breaks produced during adduct repair. Mature sperm, however, are devoid of repair enzymes, and adducts are processed only after fertilization. For this reason, comet assay is not sensitive to detect DNA lesions induced in sperm by most chemicals. To overcome such limitation, we developed a modified comet assay based on the addition of a protein extract from HeLa cells to agarose-embedded sperm on microscopic slides. To test the method, sperm were treated in vitro with methyl methanesulfonate (MMS) or melphalan (MLP) and comet assay was conducted both with and without protein supplementation. No effect of MMS or MLP was detected without protein supplementation; on the contrary, a clear-cut dose-dependent effect was measured after addition of the cell extract. These results represent a proof of concept of a novel in vitro mutagenicity test on sperm that could offer a promising approach to complement previously validated in vivo germ cell genotoxicity assays.  相似文献   
77.
目的应用基因芯片诊断前列腺癌.方法提取前列腺癌及正常前列腺组织总DNA并纯化mRNA,以包含了9个前列腺癌相关的特异基因和1个参照基因的xy检测系统cDNA临床芯片,对前列腺癌及正常前列腺组织的基因表达谱进行分析.结果9个前列腺癌相关基因检测中癌与正常组织存在显著差异,其中显著上调的有7条;显著下调有2条.结论前列腺癌临床基因诊断芯片作为前列腺癌分子水平的诊断的方法,有望提高前列腺癌的检出率.  相似文献   
78.
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.  相似文献   
79.
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN.  相似文献   
80.
目的 了解、观察葡立胶囊与抗骨增生胶囊联用治疗颈椎病对血清SOD含量及疼痛功能评分的影响。方法 对一组神经根型颈椎病患者,用葡立胶囊与抗骨增生胶囊联合应用治疗3个月,测定血清SOD含量及疼痛功能评分变化。结果 颈椎病患者治疗组血清SOD含量与治疗前相比明显升高,疼痛功能评分治疗前相比明显降低。结论 葡立胶囊与抗骨增生胶囊联合应用可明显缓解症状,提高血清SOD活力,延缓颈椎间盘退变,对治疗颈椎病有明显疗效。  相似文献   
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