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11.
激光辐照蓖麻蚕的效应探讨   总被引:1,自引:0,他引:1  
本文采用不同激光波长和不同形式的激光照射蓖麻蚕蚕卵,观察蚕卵的孵化率;蚕血液的酯酶同工酶、血清蛋白、染色体等在激光照射前后的变异情况。  相似文献   
12.
条纹斑竹鲨线粒体DNA的研究   总被引:3,自引:0,他引:3  
用6种限制性内切酶分析了4条条纹斑竹鲨的线粒体DNA(mtDNA)。PstⅠ、Hpa Ⅰ、XbaⅠ、EcoRⅠ、EcoRⅤ、BglⅡ在条纹斑竹鲨mtDNA分子上分别具有0至2个切点, mtDNA分子大小为16.6kb,根据单酶和双酶完全酶解片段的大小,构建了条纹斑竹鲨mtDNA 的限制性酶切图谱。 Abstract:Mitochondrial DNA(mtDNA)form 4 samples of Chiloscyllium plagiosum was analyzed by 6 kinds of restriction.The number of cleavage sites were as follow:2 for HpaI,XbaI and EcoRI respectively;1 for BglII and EcoRV respectively;None for PstI.Molecular size of mtDNA was found to be 16.6kb.According to analysis of single and double enzyme cleavage,the map of restriction enzyme was constructed.  相似文献   
13.
The apoptosis of HEL cells induced by hydroxyurea   总被引:1,自引:0,他引:1  
INTRODUCTIONApoptosis(programmedcelldeath)playsafundamentalroleduringinvertebrateandvertebratedevelopment.Theoriginofhumancancermaybeassociatedwiththefailureofendangeredcellstoundergoapoptosis.Apoptosishasbeenobservedinmanydifferentcellsandinresponsetomanyphysiologicalsignalsortypesofstress[1,2].Itcanbeinducedbyglucocorticoidtreatment,exposuretoCa2 ionophoresorac--irradiationofmousethymocytesandgrowthfactordeprivationofbothhematopoieticandlymphoidcellsinvitro[3,4].Hydroxyureacanstimulate…  相似文献   
14.
五种绢丝昆虫随机扩增多态性DNA分析   总被引:9,自引:2,他引:7  
桂慕燕  左正宏  陈元霖 《遗传》2001,23(1):25-28
本文对家蚕、野桑蚕、蓖麻蚕、柞蚕和天蚕等5种绢丝昆虫进行了随机扩增多态DNA(RAPD)分析。40个引物中有27个引物能扩增出536个清晰且重复性强的条带,其中可变条带数为520个,单个引物扩增的条带数在11~28之间,平均为19.9,各片段分子量大小在0.29~2.67kb之间。每个样本都能找出其独特的分子标记。家蚕与野桑蚕的遗传距离(D)最小,为0.3760;家蚕与蓖麻蚕的遗传距离(D)最大,为0.7488。根据遗传距离,用UPGMA聚类分析方法构建了它们的分子树。 Abstract:Five species of silk insects including Bombyx mori, B. manolarina, Philosamia cynthia, Autheraea pernyi and A. yamamai were analyzed by RAPD method using 40 arbitrary primers. In these primers, 27 of them could amplify clear and repeating bands. 536 fragments were obtained and the variable bands were 520. Each primer gave 11~28 bands and the average was 19.9. The length of the fragments is 0.29~2.67 kb. Some distinctive bands were found in every species. The genetic distance(D) between bombyx mori and B. manolarina is 0.3760, which is the lowest. The highest D value is 0.7488, which between Bombyx mori and Philosamia cynhia. The D value was then used to construct a dendrogram by unweighted pair-group method with arithmetical averages(UPGMA).  相似文献   
15.
左正宏  桂慕燕  王学民  陈元霖 《遗传》2001,23(2):128-130
用RAPD技术对蓖麻蚕基因组DNA进行多态性研究,分析了5个蓖麻蚕品种间的遗传差异。结果表明,所采用的40个随机引物中,有27个引物扩增谱带清晰且重复性较好,扩增总片段数达243个,单个引物的扩增片段数在4~17之间,平均为9条,片段大小在0.33~3.0kb之间。不同蓖麻蚕品种间的遗传距离(D)在0.0683~0.1603之间,根据D值,由UPGMA聚类分析软件绘制了它们的聚类分子树。 Abstract:Random amplified Polymorphic DNA (RAPD) was used to analyze the genetic diversity among eri sickworm. The genetic variance of five erisickworm was studied. The result showed that: 27 of 40 arbitrary primers could amplify clearly with repeatable bands.243 fragments were obtained.Each primer gave 4~17 bands and the average was 9.The length of the band was 0.33~3.0kb. The genetic distance (D) value between different breeds of Eri Silkworm was 0.0683~0.1603. The D value was used to construct a dendrogram by UPGMA.  相似文献   
16.
The hyperpolarization-activated current (If) plays an important role in determining the spontaneous rate of cardiac pacemaker cells. The automatic rhythmicity also exists in working cells of embryonic heart, therefore we studied developmental changes in functional expression and β-adrenergic regulation of Iy in embryonic mouse heart. The expression of If is high in early developmental stage (EDS) (10.5 d after coitus) ventricular myocytes, low in intermediate developmental stage (IDS) (13.5 d) atrial or ventricular myocytes and even lower in late developmental stage (LDS) (16.5 d) atrial or ventricular myocytes, indicating that these cells of the EDS embryonic heart have some properties of pacemaker cells.β-adrenergic agonist isoproterenol (ISO) stimulates If in LDS but not in EDS cardiomyocytes, indicating that the β-adrenergic regulation of If is not mature in EDS embryonic heart. But forskolin (a direct activator of adenylate cyclase) and 8-Br-cAMP (a membrane-permeable analogue of cAMP) increase t  相似文献   
17.
家蚕与蓖麻蚕杂交后代变异机理探讨:基因组RAPD检测   总被引:13,自引:6,他引:13  
采用24种随机引物, 对以蓖麻蚕精子进行人工授精得到的家蚕后代中的3个稳定变异品系及其亲本的基因组进行了RAPD检测, 结果显示,在变异品系的RAPD图谱中, 不仅存在大量与母本相同的“亲本带”,同时还出现了不同数量与母本不同的“变异带”,包括“非亲本带”、“缺失带”及个别仅与父本相同的“目的带”,从分子水平上揭示了变异品系存在着明显的“偏母性”与“变异性”特点。 Abstract:Twenty-four random primers were used to analyze the genomes of three descendant strains with steady hereditable variation produced form domesticated silkworm by artificial insemination with sperms of eri silkworm.The results show that in the RAPD patterns there are are many amplified bands called “parental bands” which are similar to those of the female parent.At the same time,there appears varied amount of amplified bands called“variant bnads”that are different from those of the female parent.The variant bands include non-parental-bands,lost-bands and several“expected-bands”which only shared with the male parent.This research reveals the significant matrocliny and variation in the descendant strains at the mole  相似文献   
18.
<正> 电离辐射对昆虫的作用问题,在放射生物学的全部研究中占有显著的地位。如所周知,Muller(1926)在果蝇上发现电离射线诱发基因突变的事实,从而开创了辐射遗传学,并使辐射诱变方法在育种实践中得到了应用。而且,现今在害虫防治和发展益虫的利用,如在提高柞蚕蚕丝产量等方面,应用电离辐射方法也获得了一定的成功。现有资料还表明,昆虫种类不同,个体发育期不同,以及细胞(如体细胞和生殖细胞)不同,对射线的敏感性往往很不相同。因此,比较研究昆虫的辐射效应是有意义的。  相似文献   
19.
In order to screen novel β-glucosidase producing strains from environment, one targeted novel strain PJD-1-1 producing β-glucosidase were isolated from putrefied sugarcane leaves with screening and spreading plate. 16S rDNA analysis revealed it was a novel Agrobacterium sp. When the strain was incubated at initial pH 7.0, 20 ℃ with lactose as carbon and NaNO3 as nitrogen sources, the maximum enzyme activity was 3.92 U/mg. β-glucosidase from this strain was purified using (NH4)2SO4 precipitation followed by dextran gel filtration chromatography and ion exchange chromatography. A purifying fold of 4.85 with gaining rate of 8.0% was obtained. SDA-PAGE analysis of the purified enzyme showed that it was a clear and pure band with molecular mass of ca. 40 kDa. The most optimum activity of the enzyme was at 50 ℃ and pH at 8.0. The enzyme could maintain stability under the conditions below 50 ℃. Hg2+ and Ag+ heavily inhibited the enzyme activity suggesting that the active catalytic sites of the enzymes might possess thiol radical. Ba2+, Ca2+, Pb2+, Co2+, Zn2+, Mn2+, Na+, K+, EDTA, and urea had no obvious effects on the enzyme activity. It is concluded that the novel strain Agrobacterium sp. PJD-1-1 producing β-glucosidase was successfully screened from putrefied sugar cane leaves. The produced enzyme had thermal stability, alkaline feature and metal ions tolerance made it useful in the food and broad potential applications in other fields.  相似文献   
20.
桂慕燕  左正宏  王学民  陈元霖 《遗传》2001,23(5):452-454
采用RAPD技术,对5个柞蚕品种的遗传差异进行比较研究,结果表明,所采用40个随机引物中,有27个引物扩增谱清晰且重复性较好,扩增总片段数253条,单个引物的扩增片段数在4-16之间,片段大小在0.33-3.0kb之间。不同柞蚕品种间的遗传差异较小,遗传距离(D)在0.066-0.1659之间,根据D值,由UPGMA聚类分析软件绘制了它们的分子进化树。  相似文献   
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