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81.
Guanylate binding protein-1(GBP-1)is an interferon-induced protein.To observe its antiviral effect against Hepatitis B virus(HBV)and Coxsackie virus B3(CVB3),we constructed an eukaryotic expression vector of human GBP-1(hGBP-1).Full-length encoding sequence of hGBP-1 was amplified by long chain RT-PCR and inserted into a pCR2.1 vector,then subcloned into a pCDNA3.1(-)vector.Recombinant hGBP-1 plasmids and pHBV1.3 carrying 1.3-fold genome of HBV were contransfected into HepG2 cells,and inhibition effect of hGBP-1 against HBV replication was observed.Hela cells transfected with recombinant hGBP-1 plasmids were challenged with CVB3,and viral yield in cultures were detected.The results indicated that recombinant eukaryotic expression plasmid of hGBP-1 was constructed successfully and the hGBP-1 gene carried in this plasmid could be efficiently expressed in HepG2 cells and Hela cells.hGBP-1 inhibit CVB3 but not HBV replication in vitro.These results demonstrate that hGBP-1 mediates an antiviral effect against CVB3 but not HBV and perhaps plays an important role in the interferon-mediated antiviral response against CVB3.  相似文献   
82.
中间偃麦草麦、小麦和小麦-中间偃麦草2Ai-2附加系Z1、Z2、X6,代换系ZD28等进行RAPD分析,从320个RAPD引物中,鉴定出2Ai-2染色体特异的2个RAPD标记OPO05650和OPMO414000。利用这2个特异OPO05和OPM04,PCR扩增普通小麦CS(ABD)及其近缘植物中间偃麦草(E1E2St)、拟鹅冠草(St),长穗偃麦草(E)、簇毛麦(V)、黑麦(R)、大麦(H)粗山羊草(D)等基因组DNA。结果表明,OPO05650和OPO41400均是2Ai-2染色体上St基因组区域的特异标记。将上棕2个特异片段分离回收、克隆、测序,根据测序结果重新设计、合成特异引物,成功地转换RAPD标记为SCAR(sequence characterizked amplifed region)标记SC-05和SC-M4。利用SCAR标记对不同材料进行分析的结果表明,凡含有2Ai-2染色体的抗黄矮病材料及拟鹅冠草均产生一条扩增带,不含2Ai-2染色体的材料,包括小麦、长穗麦草、簇毛麦、黑麦、在麦、粗山羊草以有含有其他他中间偃麦草染色休的附加系,均没有扩增产物,说明上棕2个SCAR标记是中间偃麦草2Ai-2染色体的特异性PCR标记,且是2Ai-2染色体上St基因组区域的特异性标记。克隆与鉴定中间偃麦草的2个SCAR扩增片段TiSCO5和TiSCM4。结果表明,克隆的中间偃麦草TiSCO5和TiSCM4特异片段,分别是St基因组特异性的寡拷贝序列有多拷贝重复序列,为St基因组遗传研究的新探针。  相似文献   
83.
通过分析本家系mtDNA序列,探讨淮阴一非综合征耳聋大家系患病的分子遗传学机制.采用聚合酶链反应(PCR)扩增mtDNA与非综合征耳聋相关位点nt1555、nt7445的区域和人类种群研究的D-loop区、PCR-异源双链分析、PCR-RFLP、PCR产物克隆序列测定等技术对该家系进行了系统的研究.发现该家系中全部母系亲属有mtDNAA1555G突变,而家系中非母系个体、对照组(100例正常个体)的mtDNA1555位点均为A.该家系mtDNA7445位点无突变;该家系属于II型线粒体;发现家系D-loop区存在未见报道的碱基插入.提示mtDNAA1555G位点突变可能是导致该家系患者致聋的主要因素之一.遗传背景可能对家系疾病的表型存在一定程度的影响。 Abstract:We find an extensive nonsyndromic sensorineural deafness family in Huaiyin,and investigate the possible molecular genetic mechanism of matrilineal nonsyndromic sensorineural deafness.We use PCR,combined with PCR-heteroduplex analysis,PCR-RFLP and sequencing techniques to examine part of 12S rRNA,tRNAser(UCN),and D-loop region of this pedigree.1)We found an A to G transition at position 1555(A1555G) of the mitochondrial 12S rRNA from all the patients and four matrilineal.2)An new nucleotide insertion was indentified in D-Loop region.3)According to the polymorphism of D-loop,this pedigree belong to mitochondrial type II.The study showed that the A1555G mutation may be one of major factors in progressive inherited deafness of this family and genetic background should be investigated in the future.  相似文献   
84.
Asian cultivated rice(Oryza sativa L.),an important cereal crop worldwide,was domesticated from its wild ancestor 8000 years ago.During its long-term cultivation and evolution under diverse agroecological conditions, Asian cultivated rice has differentiated into indica and japonica subspecies.An effective method is required to identify rice germplasm for its indica and japonica features,which is essential in rice genetic improvements.We developed a protocol that combined DNA extraction from a single rice seed and the insertion/deletion(InDel) molecular fingerprint to determine the indica and japonica features of rice germplasm.We analyzed a set of rice germplasm,including 166 Asian rice varieties,two African rice varieties,30 accessions of wild rice species,and 42 weedy rice accessions,using the single-seeded InDel fingerprints(SSIF).The results show that the SSIF method can efficiently determine the indica and japonica features of the rice germplasm.Further analyses revealed significant indica and japonica differentiation in most Asian rice varieties and weedy rice accessions.In contrast,African rice varieties and nearly all the wild rice accessions did not exhibit such differentiation.The pattern of cultivated and wild rice samples illustrated by the SSIF supports our previous hypothesis that indica and japonica differentiation occurred after rice domestication under different agroecological conditions.In addition,the divergent pattern of rice cultivars and weedy rice accessions suggests the possibility of an endoferal origin(from crop)of the weedy rice included in the present study.  相似文献   
85.
BALB/c mice were immunized with purified White spot syndrome virus (WSSV). Six monoclonal antibody cell lines were selected by ELISA with VP28 protein expressed in E. coli. in vitro neutralization experiments showed that 4 of them could inhibit the virus infection in crayfish. Western-blot suggested that all these monoclonal antibodies were against the conformational structure of VP28. The monoclonal antibody 7B4 was labeled with colloidal gold particles and used to locate the VP28 on virus envelope by immunogold labeling. These monoclonal antibodies could be used to develop immun-ological diagnosis methods for WSSV infection.  相似文献   
86.
X染色体数目及结构异常是原发性闭经的重要原因。在各类X染色体结构异常中,未见有关X染色体长臂的臂内倒位方面的报道。我室在1555例(男832例,女723例)染色体检查的患者中发现了一例,现予报告。  相似文献   
87.
黄鳝二价体上随机引物原位DNA合成的探讨   总被引:6,自引:1,他引:5  
采用随机引物,在黄鳝二价体上建立了氚标记引物原位DNA合成技术,并详细探索了该技术的实验条件。其结果显示黄鳝二价体上DNA延伸效果十分明显,银颗粒基本上是非随机性的相间排列,而且主要特征是基本稳定的,据此可以进行染色体识别。此外,还讨论了建立该技术的重要意义。 Abstract:We have developed a technique of random-primed tritium labeled DNA extension on the pachytene bivalents of rice-field eels.The bivalents were not homogeneously labeled with this technique and the extension signals were very apparent and relatively stable,and these can be applied to identify the individual bivalent.The significance to develop this technique has also been discussed in detail.  相似文献   
88.
我国畲族总人口约66万,主要分布在福建、浙江等省,其中福建有36万人,宁德地区占17万人。我国已对20多个民族的PTC尝味能力进行了调查,其中包括浙江畲族〔1〕,但福建畲族未见报道。我们用阈值法〔2〕测定宁德地区民族中学学生的苯硫脲味盲频率,其中畲族...  相似文献   
89.
A complete series of vomerine teeth of pycnodontoidea has been foundfrom the vicinity of Changtu(Sikang).It represents the first record of vertebrateremains in the Tibetan highlands.Order PycnodontoideaFamily CyrodontidaeGenus Tibetodus,new genusDiagnosis as given for the type species Tibetodus gyrodoidesSpecies Tibetodus gyrodoides,new species.Material:A vomer with the teeth nearly complete.Field No.C.3340.  相似文献   
90.
为了解旋扭山绿豆(Desmodium intortum)对低温的耐受性,以在南方各省广泛种植的优质牧草紫花大翼豆(Macroptilium atropurureum)为对照,研究了旋扭山绿豆对低温胁迫的生理响应。结果表明,低温胁迫(4℃)下,旋扭山绿豆的实际光能转化效率(Yield)和光合电子传递效率(ETR)在第2~8天时下降幅度显著低于紫花大翼豆(P0.05)。低温处理使旋扭山绿豆和紫花大翼豆超氧化物歧化酶(SOD)活性显著增加(P0.05);过氧化氢酶(CAT)活性则显著降低;旋扭山绿豆的过氧化物酶(POD)没有显著变化(P0.05),但紫花大翼豆下降了47.11%。低温处理下旋扭山绿豆游离脯氨酸和可溶性糖含量显著高于紫花大翼豆(P0.05)。回归分析、抵抗力指数和营养成分分析表明,旋扭山绿豆是一种抗寒性与营养价值均优于紫花大翼豆的优良牧草,其中Yield、ETR、CAT与渗透调节物质(游离脯氨酸和可溶性糖)可以作为旋扭山绿豆耐寒性鉴定的重要生理指标。  相似文献   
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