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1.
目的 确定我国15群15株问号钩端螺旋体(简称钩体)参考标准株和2群2株双曲钩体国际标准株携带LipL41基因情况,构建该基因的原核表达系统,鉴定表达产物的免疫原性。方法 常规酚—氯仿法提取上述17株钩体基因组DNA,高保真PCR扩增全长LipL41基因片段,T—A克隆后测序分型。构建LipL41基因原核表达系统,SDS-PAGE检测重组目的蛋白(rLipL41)表达情况。分别用钩体属特异性TP/patoe Ⅰ抗原、rLipL41兔抗血清的Western blot鉴定其免疫反应性和抗原性。分别用显微镜凝集试验(MAT)、钩体黏附J774A.1细胞模型检测兔抗rLipL41血清的交叉凝集效价和黏附阻断作用。结果 15株问号钩体均有LipL41基因,并可分为LipL41/1和LipL41/2两种基因型,2株双曲钩体则否。11个LipL41/1基因和4个LipL41/2基因克隆之间的核苷酸和氨基酸序列相似性分别为88.61%—88.67%和93.24%—97.18%。所构建的原核表达系统rLipL41/1和rLipL41/2的表达量分别占钩体总蛋白的30%和40%。rLipL41/1和rLipL41/2均能与TP/patoe Ⅰ抗血清发生结合反应,免疫家兔能产生抗体。rLipL41/1和rLipL41/2兔抗血清对上述15株问号钩体MAT效价为1:8,1:128、1:16~1:2.S6稀释时均能有效地阻断钩体对细胞的黏附。结论 我国主要的15群问号钩体代表株均有LipL41/1或LipL41/2基因。所构建原核表达系统能高效表达rLipL41/1和rLipL41/2。rLipL41/1和rLipL41/2是具有良好抗原性和免疫反应性、广泛存在于不同血清群问号钩体表面的蛋白抗原。  相似文献   

2.
目的 分析我国15群15型问号钩端螺旋体(简称钩体)参考标准株外膜脂蛋白lipL21基因序列,构建该基因原核表达系统并鉴定表达产物的免疫原性,了解lipL21基因自然表达状况。方法 高保真PCR扩增上述问号钩体株及双曲钩体Paloc型PalocⅠ株基因组DNA中全长lipL21基因片段,T-A克隆后测序并构建其原核表达系统。分别用钩体TR/PatocⅠ和rLipL21兔抗血清为一抗的Western blot鉴定目的重组蛋白rLipL21的免疫原性,显微镜凝集试验(MAT)检测rLipL21兔抗血清的交叉凝集效价。以盐变-去垢剂处理法提取钩体外膜蛋白,用SDS-PAGE和免疫印迹法检测上述钩体株lipL21基因自然表达情况。结果 上述钩体株均存在序列高度保守的lipL21基因,其核苷酸和氨基酸序列相似性分别为98.75%~99.82%和99.46%~100%。rLipL21能与TR/PatocⅠ及rLipL21兔抗血清发生结合反应。rLipL21免疫家兔能产生抗体,该抗体对上述15株问号钩体MAT效价为1:16~1:128。问号钩体外膜标本中均可检出LipL21,双曲钩体则否。结论 我国钩体群参考标准株均含有序列保守的lipL21基因并自然表达于外膜,双曲钩体PatocⅠ株虽含有lipL21基因但未表达。rLipL21具有良好的抗原性和免疫反应性,有可能作为新型钩体疫苗或检测试剂盒的候选属特异性表面抗原之一。  相似文献   

3.
目的 确定问号钩端螺旋体(简称钩体)属特异性脂蛋白抗原LipL32膜定位及其自然抗体应答情况和抗体类型.方法 IPTG诱导目的 重组蛋白rLipL32-1和rLipL32-2表达,Ni-NTA亲和层析法提纯rLipL32.采用显微镜凝集试验(MAT)检测四川地区钩体患者血清标本及rLipL32兔抗血清与我国问号钩体参考标准株的交叉凝集情况.采用胶体金免疫电镜技术对LipL32进行膜定位.建立基于rLipL32的ELISA,检测钩体患者血清中特异性抗体类型及其水平.结果 黄疸出血群是四川地区最主要的优势钩体血清群.rLipL32兔抗血清均能与我国问号钩体参考标准株发生MAT效价为1∶80~1∶320的交叉凝集反应.LipL32是位于钩体外膜表面的蛋白质分子.156例MAT阳性钩体患者血清标本中,rLipL32-1和rLipL32-2特异性IgM阳性率分别为91.0%~92.9%和90.4%~92.3%,特异性IgG阳性率分别为99.4%和97.4%~98.1%.结论 LipL32是问号钩体属特异性表面蛋白抗原.自然感染钩体时,LipL32-1和LipL32-2可诱导机体产生IgM和IgG两类血清抗体.rLipL32-1和rLipL32-2可作为研制检测试剂盒的候选抗原.  相似文献   

4.
目的 构建问号钩端螺旋体(简称钩体)LipL32、OmpL1和LipL21蛋白的优势T-和B-细胞联合表位融合基因及其原核表达系统,并对表达产物的免疫原性进行鉴定.方法 人工合成多表位联合基因并构建其原核表达系统.采用SDS-PAGE检测重组蛋白;采用MAT检测重组蛋白兔抗血清与我国钩体标准参考株的凝集效价;Western blot和ELISA检测重组蛋白的免疫原性.结果 获得了多表位融合基因并构建了原核表达系统.表达产物的相对分子质量约为23×103,且主要以可溶性形式存在;重组蛋白兔抗血清免疫双扩散效价为1∶8,该抗血清能与我国15群的钩体标准参考株发生凝集反应,ELISA证明该重组蛋白能检测不同群型钩体感染患者血清中的抗钩体抗体.结论 成功构建了包含钩体LipL32、OmpL1和LipL21蛋白的优势T和B细胞联合表位基因及其原核表达系统,表达产物具有良好的抗原性和交叉免疫反应性,可作为研制通用型问号钩体基因工程疫苗及血清学检测的抗原.  相似文献   

5.
目的 探讨 15群 15型问号钩端螺旋体 (简称钩体 )中国参考标准株及 2群 2型双曲钩体国际参考标准株是否均存在主要外膜蛋白 (MOMP)基因 (LipL32 ) ,克隆并构建该基因的原核表达系统 ,鉴定表达产物的免疫性。方法 常规酚 氯仿法提取上述钩体株基因组DNA ,高保真PCR扩增全长LipL32基因片段 ,T A克隆后测定核苷酸序列并构建表达系统 ,不同浓度IPTG诱导后用SDS PAGE检测rMOMP表达情况。分别用兔抗TR patocⅠ钩体全菌抗血清、rMOMPs免疫兔血清的Westernblot鉴定其免疫反应性和免疫原性 ,显微镜凝集试验 (MAT)检测rMOMPs免疫兔血清的交叉凝集效价 ,钩体细胞黏附模型检测抗体阻断效果。结果 上述 17株钩体均有LipL32基因 ,但可分LipL32 1和LipL32 2两种基因型。 13个LipL32 1和 4个Li pL32 2基因型之间核苷酸和氨基酸序列同源性分别为 95 .12 %~ 96 .6 0 %和 97.79%~ 98.16 %。IPTG诱导后rMOMP1和rMOMP2表达量分别占细菌总蛋白的 4 0 %和 10 %。rMOMP1和rMOMP2均能与兔抗钩体TR patocⅠ血清发生结合反应 ,免疫家兔可对上述 17株钩体产生 1∶2~ 1∶6 4MAT效价的凝集抗体。 1∶2~ 1∶16稀释的兔抗rMOMP1和rMOMP2血清均能有效地阻断钩体的黏附。结论 所有检测的钩体具有LipL32 1或LipL32 2基因。所  相似文献   

6.
目的 构建问号钩端螺旋体(简称钩体)主要外膜蛋白OmpL1、LipL21和LipL32优势抗原表位的串联基因及其表达系统,了解该重组蛋白的免疫活性.方法 采用噬菌体M13KE表面展示技术结合Western blot分析,鉴定了OmpLl、LipL21和LipL32的优势抗原表位,人工合成优势抗原表位串联基因并构建其原核表达系统.SDS-PAGE检测重组蛋白的表达情况;Western blot及ELISA鉴定重组蛋白的免疫活性.结果 该合成基因在原核表达系统中得到了有效表达,且表达产物主要以可溶性形式存在.Western blot和ELISA结果 显示该重组蛋白能与兔抗钩体全菌抗体及不同血清群的钩体病人血清中的抗体产生免疫反应.结论 本研究成功构建了钩体多表位串联基因及其表达系统,所表达目的 蛋白具有良好的免疫活性,且对不同血清群型抗体之间均有免疫原活性.  相似文献   

7.
问号钩端螺旋体病人血清中LipL21抗体检测   总被引:1,自引:0,他引:1  
寻找钩体属特异性保护抗原,对于研制通用型钩体疫苗及实验室诊断试剂盒均有重要价值。Cullen等首先报告了致病性问号钩体均具有属特异性lipL21脂蛋白基因。我们也曾证实我国15群15型问号钩体参考标准株均含有序列保守的lipL21基因。已知钩体病免疫保护作用主要依赖血清抗体为主的体液免疫。我们采用显微镜凝集试验(MAT)检测了156份钩体病人血清的凝集效价,并建立rLipL21-IgM/IgG-ELISAs对血清标本中LipL21的IgG和IgM型抗体进行了检测。  相似文献   

8.
目的 探讨15群15型问号钩端螺旋体(简称钩体)中国参考标准株及2群2型双曲钩体国际参考标准株是否均存在外膜蛋白OmpL1基因,克隆并构建该基因的原核表达系统,鉴定表达产物的免疫性。方法 常规酚.氯仿法提取上述钩体的基因组DNA,高保真PCR扩增全长OmpL1基因片段,T-A克隆后测定核苷酸序列并构建原核表达系统,不同浓度lPTG诱导后用SDS-PAGE检测重组蛋白rOMPLI表达情况。分别用兔抗钩体TR/PatocⅠ抗原、rOMPL1血清的Westernblot鉴定其免疫反应性和免疫原性。分别用显微镜凝集试验(MAT)和钩体细胞黏附模型检测兔抗rOMPLI血清的交叉凝集效价和细胞黏附阻断作用。结果 上述17株钩体均具有OmpL1基因,但至少可分3种基因型:OmpL1/1、OmpL1/2和OmpL1/3。与文献报道比较,所克隆的OmpL1/1、OmpL1/2和OmpL1/3基因核苷酸序列同源性分别为93.87%~94.08%、89.82%~100%和80.89%~81.72%,其氨基酸序列同源性分别为93.13%~98.75%、91.87%~100%和85.63%~88.44%。IPTG诱导后pET32a-OmpL1/1.E.coli/BL21DE3和pET32a-OmpL1/2-E.coliBL21DE3的rOMPL1/1和rOMPL1/2表达量分别占细菌总蛋白的30%和20%。rOMPL1,1和rOMPLl,2均能与兔抗钩体TR/PatocⅠ抗原血清发生免疫结合反应,免疫家兔可获得抗体。兔抗rOMPL1/1和rOMPL1/2血清对上述17株钩体的MAT效价为1:2.1:32,1:2.1:16稀释时均能有效地阻断钩体黏附J744A.1细胞。结论 所检测的钩体均有OmpLl基因,但至少可分为3种不同的基因型。所构建的原核表达系统表达的rOMPL1/1和rOMPL1/2具有良好的免疫原性和免疫反应性。rOMPL1/1和rOMPL1/2具有属特异性、钩体表面的膜蛋白抗原,能诱生交叉凝集抗体,并具有钩体黏附阻断的作用。  相似文献   

9.
目的 构建致病性问号钩端螺旋体(简称钩体)黄疸出血群赖型赖株vwA1和vwA2基因原核表达系统,初步了解目的重组表达产物rVwA1和rVwA2与血小板性出血相关性.方法 采用高保真PCR扩增问号钩体赖株vwA1和vwA2基因并测序,常规方法构建vwA1和vwA2基因原核表达系统.采用SDS-PAGE联合Bio-Rad凝胶图像分析系统检查rVwA1和rVwA2表达情况及其可溶性,Ni-NTA亲和层析柱提纯rVwA1和rVwA2.采用实时荧光定量RT-PCR检测问号钩体赖株感染人脐静脉内皮细胞株HUVEC前后vwAl-mRNA和vwA2-mRNA水平变化.采用流式细胞术检测rVwA1与人血小板膜糖蛋白结合能力.采用酶切试验及SDS-PAGE观察人血管性血友病因子裂解酶ADAMTS13水解rVwA2的情况.结果 所克隆的钩体vwA1和vwA2基因与报道的相应基因比较,其核苷酸和氨基酸序列相似性均为100%.所构建的vwA1和vwA2基因原核表达系统能分别表达可溶性rVwA1和rVwA2.问号钩体赖株感染HUVEC 8 h后,钩体vwAl-mRNA和vwA2-mRNA水平均显著上调(P<0.05).流式细胞术检测结果显示,钩体rVwA1与人血小板结合率为60.8%.人ADAMTS13可水解重组人vWF-A2( rhvWF-A2),但不能水解钩体rVwA2.结论 vwA1和vwA2基因可能在钩体感染中发挥作用,其中vwA1基因产物功能与钩体病出血密切相关.  相似文献   

10.
目的 确定我国不同基因种问号钩端螺旋体(简称钩体)参考标准株携带毒力相关基因invA的情况,了解问号钩体赖株感染细胞前后invA基因转录和表达水平的变化.方法 采用PCR检测4个不同基因种问号钩体株及双曲钩体Patoc Ⅰ株invA基因.克隆问号钩体全长invA基因并测序,构建问号钩体黄疸出血群赖型赖株invA基因原核表达系统.Ni-NTA亲和层析法提纯目的重组蛋白rlnvA后免疫家兔获得抗血清,免疫双扩散法检测其效价.建立问号钩体赖株感染人胚肾上皮细胞HEK293模型,采用荧光定量RT-PCR和Western blot分别检测问号钩体赖株感染HEK293细胞前后invA基因的转录和表达水平的变化.结果 4个不同基因种的问号钩体株均含有invA基因,双曲钩体Patoc Ⅰ株则否.4株不同基因种的问号钩体invA基因核苷酸和氨基酸序列相似性分别为99.33%~100%和98.66%~100%.所构建的原核表达系统能有效地表达rInvA.rInvA兔抗血清免疫双扩效价为1:16.问号钩体赖株感染HEK293细胞30 min以后可大量黏附于细胞表面.问号钩体赖株感染HEK293细胞30 min时,invA基因mRNA水平明显上调,45 min时达到峰值,然后逐渐下降.问号钩体赖株感染HEK293细胞后45 min和60 min时可检出InvA蛋白,感染前及感染90 min以后检测结果均为阴性.结论 invA基因是致病性问号钩体所特有的基因.invA基因具有宿主细胞接触式表达及瞬时表达的特点,与问号钩体侵入宿主细胞密切相关.  相似文献   

11.
中国人中发现一例Charcot-Marie-Tooth病连接蛋白32基因新突变   总被引:1,自引:0,他引:1  
目的了解中国人进行性腓骨肌萎缩症(Charcot-Marie-Toothdisease,CMT)连接蛋白32(connexin32,Cx32)基因外显子2的突变情况.方法对6例无亲缘关系的、无重复的CMT1患者和10例无亲缘关系的CMT2患者进行SSCP分析,对有异常者进行测序,根据突变点序列设计合适的内切酶,对50名正常对照进行酶切分析.结果在1例CMT1患者发生了Gly21Asp(62G→A)错义突变.用限制性内切酶H-aeⅡ酶切50名正常对照未见异常,表明该突变为致病性突变.结论Gly21Asp是未报道过的新型突变,中国人CMT1患者中CMTX患者可能占一定比例.  相似文献   

12.
We studied the relationship between the genotype and clinical phenotype in 27 families with dominant X-linked Charcot-Marie-Tooth (CMTX1) neuropathy. Twenty-two families showed mutations in the coding region of the connexin32 (cx32) gene. The mutations include four nonsense mutations, eight missense mutations, two medium size deletions, and one insertion. Most missense mutations showed a mild clinical phenotype (five out of eight), whereas all nonsense mutations, the larger of the two deletions, and the insertion that produced frameshifts showed severe phenotypes. Five CMTX1 families with mild clinical phenotype showed no point mutations of the cx32 gene coding region. Three of these families showed positive genetic linkage with the markers of the Xq13.1 region. The genetic linkage of the remaining two families could not be evaluated because of their small size. © 1996 Wiley-Liss, Inc.  相似文献   

13.
Results from the published studies on the association between chemokine receptor 5 (CCR5) Δ32/W gene polymorphism and lupus nephritis (LN) are still conflicting. This meta-analysis was performed to evaluate the relationship between CCR5 Δ32/W gene polymorphism and LN and to explore whether CCR5 Δ32 allele, Δ32/Δ32 and W/W genotypes could become a predictive marker for systemic lupus erythematosus (SLE) developing into LN. Association studies were identified from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) as of March 1, 2014, and eligible investigations were synthesized using meta-analysis method. Results were expressed with odds ratios (OR) for dichotomous data, and 95% confidence intervals (CI) were also calculated. Five investigations were identified for the analysis of association between CCR5 Δ32/W gene polymorphism and LN. In the overall populations, Asians, Caucasian population, the association between CCR5 Δ32/W gene polymorphism and LN susceptibility was not found. Interestingly, a trend toward an association of Δ32 allele and W/W genotype with LN risk was observed in African population. However, this meta-analysis only included one study for the study in Africans. We also found that the gene distribution of CCR5 Δ32/W gene polymorphism between SLE group and LN group were not different. In conclusion, our results indicate that CCR5 Δ32/W gene polymorphism was not associated with LN risk and might be no a significant genetic molecular marker to predict the SLE patients developing into LN. However, more investigations are required to further clarify this association.  相似文献   

14.
Response gene to complement 32 (RGC-32) is a cell cycle regulator involved in the proliferation, differentiation and migration of cells and has also been implicated in angiogenesis. Here we show that RGC-32 expression in macrophages is induced by IL-4 and reduced by LPS, indicating a link between RGC-32 expression and M2 polarization. We demonstrated that the increased expression of RGC-32 is characteristic of alternatively activated macrophages, in which this protein suppresses the production of pro-inflammatory cytokine IL-6 and promotes the production of the anti-inflammatory mediator TGF-β. Consistent with in vitro data, tumor-associated macrophages (TAMs) express high levels of RGC-32, and this expression is induced by tumor-derived ascitic fluid in an M-CSF- and/or IL-4-dependent manner. Collectively, these results establish RGC-32 as a marker for M2 macrophage polarization and indicate that this protein is a potential target for cancer immunotherapy, targeting tumor-associated macrophages.  相似文献   

15.
目的:克隆人白细胞介素32(hIL-32)基因,构建高效稳定的hIL-32大肠杆菌表达菌株,并对纯化的目的蛋白进行生物学活性的初步测定.方法:将人外周血单个核细胞( PBMC)经刀豆素A( Con A)刺激60 h后提取细胞的总RNA,通过逆转录聚合酶链式反应( RT-PCR)从刺激的PBMC中扩增出hIL-32的基因,通过基因克隆技术,构建hIL-32在pET-30 a(+)中的重组质粒pET30a-hIL32,用IPTG进行诱导,得到hIL-32的原核表达蛋白;采用Ni2+ -NTA亲和层析方法纯化目的蛋白;应用ELISA方法检测纯化蛋白诱导人PBMC产生IL-6的情况.结果:序列测定表明,hIL-32基因核苷酸长度为567 bp,编码189个氨基酸.重组质粒pET30 -hIL32转化至大肠杆菌BL21( DE3),重组菌菌体裂解物SDS-PAGE可检测到相对分子质量(Mr)为28 000的重组蛋白,表达的重组蛋白IL-32可促进人PBMC产生IL-6,浓度达到(127±4.8)ng/L,而对照组IL-6的浓度仅为(25±2.3)ng/L.结论:成功克隆了hIL-32基因并构建了高效且稳定表达hIL-32基因的大肠杆菌菌株,且表达的目的蛋白能诱导IL-6细胞因子的产生.  相似文献   

16.
OBJECTIVE: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-delta32/delta32 homozygous genotype has phenotypic expressions other than those related to HIV-1. DESIGN: Study subjects were white homosexual men or men with hemophilia who were not infected with HIV-1. In this study, 15 CCR5-delta32/delta32 homozygotes were compared with 201 CCR5 wild-type (+/+) subjects for a wide range of clinical conditions and laboratory assay results ascertained during prospective cohort studies and routine clinical care. CCR5-delta32 genotype was determined by polymerase chain reaction, followed by single-stranded conformational polymorphism analysis. RESULTS: Hypertension and conditions attributable to hemophilia were the only diagnoses frequently found in clinical records of CCR5-delta32/delta32 study subjects. Based on blood pressure measurement and treatment history, CCR5-delta32/delta32 homozygotes had a 2.8-fold higher prevalence of hypertension than age-matched CCR5-+/+ study subjects (95% confidence interval [CI], 1.2-6.4; p = .01); none of the homozygotes had severe hypertension. Hematologic measures were generally similar across the genotypes, but total lymphocyte counts were approximately 20% higher in CCR5-delta32/delta32 study subjects than in CCR5-+/+ study subjects (p < .05). Among patients with hemophilia who were infected with hepatitis C virus (HCV), mean alanine aminotransferase levels were 117% higher among CCR5-delta32/delta32 homozygotes (p < .05), but serum HCV levels did not differ by CCR5-delta32 genotype. CCR5-delta32/delta32 homozygous study subjects had a lower prevalence of antibodies to measles virus than those with other genotypes, but this association was not confirmed in a group of blood donors. The prevalence of antibodies to nine other common viruses, HBV, and HCV was not related to CCR5 genotype. CONCLUSIONS: CCR5-delta32/delta32 homozygotes are generally similar to wild-type persons. Confirmatory investigations are required to determine whether hypertension, increased lymphocyte counts, and higher hepatic enzyme levels in the presence of HCV infection represent true phenotypic expressions of this genotype. CCR5-delta32/delta32 homozygosity does not provide broad protection against viral infections.  相似文献   

17.
为观察NO供体硝普钠对体外培养的海马神经元cpp32基因表达的影响,采用终浓度分别为0、25、50、100、200、400μmol/L的硝普钠处理海马神经元24h,用RT-PCR检测mRNA表达变化,Western blot检测蛋白表达的变化;再用终浓度分别为0、25、50、100、200μmol/L的硝普钠处理海马神经元12h,用CPP32活性检测试剂盒检测CPP32酶活性。结果表明,随着硝普钠剂量的增加,cpp32mRNA表达无改变;但CPP32酶原被裂解活化,从50μmol/L硝普钠起,酶活性显著增加,为对照组的3.02倍,100μmol/L达最大值,为对照组的3.47倍,这说明硝普钠不增加cpp32 mRNA的表达,但可诱导CPP32酶原的裂解,使CPP32活化。  相似文献   

18.
Sheep pox and Goat pox are highly contagious viral diseases of small ruminants. These diseases were earlier thought to be caused by a single species of virus, as they are serologically indistinguishable. P32, one of the major immunogenic genes of Capripoxvirus, was isolated and Sequenced from two Indian isolates of goat poxvirus (GPV) and a vaccine strain of sheep poxvirus (SPV). The sequences were compared with other P32 sequences of capripoxviruses available in the database. Sequence analysis revealed that sheep pox and goat poxviruses share 97.5 and 94.7% homology at nucleotide and amino acid level, respectively. A major difference between them is the presence of an additional aspartic acid at 55th position of P32 of sheep poxvirus that is absent in both goat poxvirus and lumpy skin disease virus. Further, six unique neutral nucleotide substitutions were observed at positions 77, 275, 403, 552, 867 and 964 in the sequence of goat poxvirus, which can be taken as GPV signature residues. Similar unique nucleotide signatures could be identified in SPV and LSDV sequences also. Phylogenetic analysis showed that members of the Capripoxvirus could be delineated into three distinct clusters of GPV, SPV and LSDV based on the P32 genomic sequence. Using this information, a PCR-RFLP method has been developed for unequivocal genomic differentiation of SPV and GPV.  相似文献   

19.
鼻咽癌染色体7q32区域微缺失的研究   总被引:7,自引:1,他引:6  
目的 进一步明确鼻咽癌染色体7q32的D7S500-D7S495附近区域高频率等位基因缺失的范围。方法 采用更高密度的微卫星标记位点,分析30个鼻咽癌病例等位基因杂合性缺失的情况。结果 30例 患者中有19例(63.3%)存在杂合性缺失;D7S500-D7S509-D7S495是高频率缺失集中的区域,共同缺失区在D7S509附近。结论 D7S509附近可能存在与鼻咽癌发病相关的抑癌基因。  相似文献   

20.
Leptospirosisisoneofthemostimportantinfectiousdis easeinwaterloggingareasandpaddies[1 3].Thecur rentlyusedmultivalentvaccinesagainstleptospirosisare preparedfromdeadLeptospira[4 6].Sincethecross immuneprotectionamongdifferentserovarsofL.interro gansis…  相似文献   

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