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131.
132.
大肠癌中p53基因突变的研究 总被引:2,自引:0,他引:2
应用聚合酶链反应(PCR)──单链构型多态性(SSCP)结合银染法对14例大肠癌p53基因的第4、第5─6和第7外显子进行了点突变的研究,结果共检测出6例点突变,而且发现各外显子的突变频率存在差异。另外,利用购自ATCC的两个探针 (p53cDNA探针和pYNZ22探针)对大肠癌中p53基因的杂合性失去进行了研究,在14例大肠癌中共检出6例杂合性丢失。将点突变检测结果同杂合性丢失结果进行比较分析, 并着重探讨了大肠癌中p53基因失活导致肿瘤的作用方式。
Abstract:The exons 4-7 of p53 gene were examined in 14 colorectal Cancer patients by using PCR-SSCP-silver staining method.The results showed 6 cases of point mutation and the mutation frequencies of exons were different from each other.p53 cDNA and pYNZ22 VNTR were used as probes to examine LOH(Loss of heterozygosity)of 14 colorectal cancers.6 cases with LOH were found.The results of present research suggest that mutation and LOH of p53 gene are critical events in the progress and development of Cancer.There were different kinds of inactivation model of p53 gene in the process of development of cancer and transformation of cells. 相似文献
133.
将1mm厚凝固于复印膜上的水琼脂(15%~2.0%)凝胶板侵入含12mmol/L植酸钠的Gly—HCl缓冲液中达1h以上,取出干至胶表面无水迹,于上加Aspergillussp.59—2植酸酶或与电泳后的凝胶板紧贴10~60min。然后水平置于恒温水浴锅中反应一定时间,取出浸入1mol/LH2SO4-2%(NH4)6Mn7O24-10%FeSO4相似文献
134.
Mutations in the homologous ZDS1 and ZDS2 genes affect cell cycle progression. 总被引:3,自引:2,他引:1
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Y Yu Y W Jiang R J Wellinger K Carlson J M Roberts D J Stillman 《Molecular and cellular biology》1996,16(10):5254-5263
135.
The effects on the redlegged earth mite (Halotydeus destructor) (Acarina: Penthaleidae) of volatile compounds released from artificially damaged cotyledons of subterranean clover (Trifolium subterraneum L.), a host plant, were investigated with different assays. Mites were repelled by the volatile compounds in flask tube and in trimmed cotyledon disc tests. No differences could be shown between different tissue amounts and between resistant and susceptible varieties. When a membrane sachet was used containing either 2-(E)-hexenal, a compound produced by damaged subclover cotyledons, or the total volatile compounds collected from damaged cotyledons of Dalkeith (susceptible) admixed with 1% glucose, mites gathered to low but were deterred by high concentrations of the compounds. Volatile compounds collected from the resistant variety DGI007 were more deterrent than those from the susceptible Dalkeith. Membrane sachets containing 30 p.p.m. of 2-(E)-hexenal and 1% glucose were less preferred than cotyledons of Dalkeith (susceptible) but were not different from DGI007 (resistant). By increasing the glucose concentration to 5%, the membrane sachets with 30 p.p.m. of 2-(E)-hexenal were preferred to cotyledons of either variety. The results indicate that the membrane feeding technique provides a sensitive way of assaying volatile compounds from damaged subclover cotyledons against the mite. 相似文献
136.
Six pesticides and two spray oils were tested against Polyphagotarsonemus latus. The chemicals were evaluated under laboratory conditions, requiring the development of a novel bioassay method, which is reported here. The pesticide toxicities fell into three distinct groups, namely abamectin, conventional pesticides and oils. The relative pesticide toxicities at the LC50 level were abamectin 4.9×10-8 g ai l-1, endosulfan 1.1×10-3 g ai l-1, fenpyroximate 2.3×10-3 g ai l-1, pyridaben 4.1×10-3 g ai l-1, tebufenpyrad 4.4×10-3 g ai l-1, dicofol 4.5×10-3 g ai l-1, petroleum spray oil 3.4×10-1 g ai l-1 and canola oil 4.1×10-1 g ai l-1. The calculation of the LC99.9 values allows for resistance monitoring in P. latus and the suggested discriminating concentrations are abamectin 1.0×10-4 g ai l-1; endosulfan, pyridaben and dicofol 1.0×10-1 g ai l-1 fenpyroximate and tebufenpyrad 5.0×10-1 g ai l-1. 相似文献
137.
138.
DNA polymerase epsilon may be dispensable for SV40- but not cellular-DNA replication. 总被引:9,自引:1,他引:8
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![点击此处可从《The EMBO journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T Zlotkin G Kaufmann Y Jiang M Y Lee L Uitto J Syvoja I Dornreiter E Fanning T Nethanel 《The EMBO journal》1996,15(9):2298-2305
The contributions of DNA polymerases alpha, delta, and epsilon to SV40 and nuclear DNA syntheses were evaluated. Proteins were UV-crosslinked to nascent DNA within replicating chromosomes and the photolabelled polymerases were immunopurified. Only DNA polymerases alpha and delta were detectably photolabelled by nascent SV40 DNA, whether synthesized in soluble viral chromatin or within nuclei isolated from SV40-infected cells. In contrast, all three enzymes were photolabelled by the nascent cellular DNA. Mitogenic stimulation enhanced the photolabelling of the polymerases in the alpha>delta>epsilon order of preference. The data agree with the notion that DNA polymerases alpha and delta catalyse the principal DNA polymerisation reactions at the replication fork of SV40 and, perhaps, also of nuclear chromosomes. DNA polymerase epsilon, implicated by others as a cell-cycle checkpoint regulator sensing DNA replication lesions, may be dispensable for replication of the small, fast propagating virus that subverts cell cycle controls. 相似文献
139.
用地高辛标记探针在人染色体上进行了基因定位。使用了酶显色和荧光显色,两者得到了相同的定位结果,特异区阳性率分别为11.6%和19.8%’荧光显色特异性较高,说明基因定位效果受显示系统效率的影响,地高辛标记探针用于基因定位有比放射性探针、生物素探针更多的优越性。又讨论了几个影响效果的因素,提出以SDC代替甲酰胺洗涤;紫外照射于杂交前R显带方法能取得较好的基因定位效果。 相似文献
140.
云南土壤放线菌生态分布的研究 总被引:11,自引:1,他引:10
云南具有极为复杂的地理气候。根据云南省不同的地质、地理、土壤、气候、植被特点选择样区,采集土壤样品,研究了云南不同地区、不同生态环境放线菌的生态分布与植被的关系。将云南土壤放线菌区系划分为热带区系、亚热带高原区系、滇西北高山区系和雪山区系四种类型。对云南土壤放线菌区系的特点进行了讨论。 相似文献