| 1. | Compared with the mild strain from india and wisconsin u . s . a . , there were only a few mutations in central conserved dormain
从而进一步推测中国pstvd的发生可能是随着irishcobbher品种引入我国而带来的。 |
| 2. | To device a primer pairs and amplify the full length pstvd by rt - pcr , the positive rna extraction from tuber sample was used as template . the product of rt - pcr was purified and connected to the plasmid pmd 18 - t vector
Cdna核酸斑点杂交反应( nash )检测pstvd方法准确、灵敏度高，一次检测样品数量多，且对于异地样品检测非常方便，是以往其它检测方法的有效补充。 |
| 3. | All the samples with typical potato spindle tuber viroid ( pstvd ) symptoms collected from the fields in the northeast region of china were detected by the r - page method . the positive samples were verified . then , two - dimensional page and rt - pcr techniques were adapted in deleting pstvd
对采自中国东北佳木斯、大庆等地区具有典型马铃薯纺锤块茎类病毒( pstvd )症状的薯块样品进行往返电泳( r - page ) ，确定含马铃薯纺锤块茎类病毒的阳性样品。 |
| 4. | They were capable of detecting 50 pg of purified total rna by a colorimetric assay and 5 pg by a chemiluminescent assay . the nonradioactive probe produced with pcr amplification were particularly suitable for practical diagnosis , as they are sensitive and can be rapidly prepared in large quantities . the two assay methods were 260 times and 26 times as sensitvity as r - page respectively
利用含pstvd单体的pgem - 7z质粒，通过pcr扩增技术，用生物素标记制备cdna探针，进行杂交反应检测pstvd ，其中通过化学颜色反应进行判读灵敏度可达到50pg ，而用化学发光反应进行判读灵敏度可达到5pg ，分别是r - page检测灵敏度的260倍和26倍。 |
| 5. | It can be futher verified by the test result that the pstvd found in the northeast region of china may be introduced into china by following the introduction of the potato cultivar irish cobbler to various countries and irish cobbler was imported in heilongjiang province prior to the 1960s
在国内，首次对中国分离株系进行cdna基因克隆和序列分析，进一步验证了中国株系的由来及其结构特点，对于中国在pstvd检测水平的提高、检测试剂盒制备、 pstvd的防治及其致病机理、转基因育种等提供重要依据。 |
| 6. | Then , the plasmid was transformed into jm109 . the full length pstvd cdna recombinant plasmid was further identified by restriction mapping analysis and the nucleotide sequence of cdna cloned in pmd 18 - t vector was analyzed with ab1 377 dna sequence . test showed that the cdna of this chinese pstvd isolate was the same as pstvd - kf - 6 mild " type " isolate which originated from naturally infected potatoes in field of cornell university potato breeding program
利用rt - pgr技术，设计一对引物，对田间采集的经鉴定含pstvd的阳性样品进行全序列扩增，并将所得产物纯化回收，连接到pmd18t - vector中，并转化至大肠杆菌jm109中，挑选白斑进行双酶切( saci / ecorv )鉴定证明插入片段为359bp大小，进行序列测定，所得克隆基因为pstvd全序列负链，大小为359bp 。 |
