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1.
通过比较小麦与玉米及鸭茅状摩擦禾属间杂交获得的胚与小麦正常自交的胚之间在不同发育时期过氧化物酶和酯酶的同工酶谱,发现过氧化物酶同工酶表现出时空顺序的特异性变化。在同一发育时期,远缘杂交的具胚子房和无胚子房之间存在过氧化物酶同工酶谱的差异,这可能涉及到与胚发育相关的同工酶的出现。远缘杂交的具胚子房和正常自交的小麦子房之间也有一定的酶谱差异。同时,同一材料还表现出不同发育时期的过氧化物酶酶谱差别。在远缘杂交后的胚发育期间,酯酶同工酶的时空表达不如过氧化物酶显著。此外,对远缘杂交后的胚中的水溶性蛋白质进行了SD S-PAGE分析,初步的分析结果表明,可能存在与胚发育相关的蛋白质。  相似文献   
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MethodsforHandy,RapidIsolationofHighQualityRNAbyGuanadiumThioeyauateDuJianYuanYanhuaMaShenglinDongZhiwei(BeijingInstituteforCancerResearchBeijing100034)硫氰胍是一种有效的蛋白变性剂。早在1979年,Chirgwin等就利用氯化铯/硫氰胍超离心技术成功地从RNA酶富集的胰脏组织中提取出未降解的RNA分子[2],从而使它成为抑制RNA酶的首选药物并得到广泛使用,但受到超速离心设备的限制。1983年,Cathala报道了氯化锂/硫氰胍RNA提取法[1]。该方法操作简便,获得的RNA质量很高,但所需时间较长。为了能在短时间内更快…  相似文献   
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Atomic force microscopy (AFM) was used to examine the morphology of live mammalian adherent and suspended cells. Time-lapse AFM was used to record the locomotion dynamics of MCF-7 and Neuro-2a cells. When a MCF-7 cell retracted, many small sawtooth-like filopodia formed and reorganized, and the thickness of cellular lamellipodium increased as the retraction progressed. In elongated Neuro-2a cells, the cytoskeleton reorganized from an irregular to a parallel, linear morphology. Suspended mammalian cells were immobilized by method combining polydimethylsiloxane-fabricated wells with poly-L-lysine electrostatic adsorption. In this way, the morphology of a single live lymphoma cell was imaged by AFM. The experimental results can improve our understanding of cell locomotion and may lead to improved immobilization strategies.  相似文献   
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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   
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张树成  崔应琦 《遗传》1990,12(6):25-26
本文通过对男性、女性成年人和儿童的外周血淋巴细胞的染色体畸变率、染色体畸变类型性的染色体畸变分析,微核,姐妹染色单体交换,及细胞有丝分裂指数、细胞周期比率、细胞增值指数的细胞动力学研究等8项参数、综合分析年龄和性别对其遗传安全性检测指标的影响。结果8项参数在成年人中均显示男性高于女性的趋势;除细胞畸变率外,其他7项参数在男性和女性中均显示成年人高于儿童的趋势。由本试验初步认为,年龄和性别对遗传安全性检测指标存在一定影响。  相似文献   
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The importance of aquatic vegetation to the ecologi-cal restoration has been recognized commonly bylimnolo-gists and lake managements[1—4].As to the ecologicalrestoration in eutrophicated lakes,it is of great signifi-cance to knowthe dynamic process of the ecosystemevo-lution in a macrophyte-dominated lake under the humanimpacts in historical period,to make it clear whether thecommunitystructure and ecological function would be af-fected bythe extension of the vegetation growth,tofind asolutionto remain ste...  相似文献   
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Microbial synthesis of functional polymers has become increasingly important for industrial biotechnology.For the first time,it became possible to synthesize controllable composition of poly(3-hydroxyalkanoate)(P3HA)consisting of 3-hydroxydodecanoate(3HDD)and phenyl group on the side-chain when chromosome of Pseudomonas entomophila was edited to weaken itsβ-oxidation.Cultured in the presence of 5-phenylvaleric acid(PVA),the edited P.entomophila produced only homopolymer poly(3-hydroxy-5-phenylvalerate)or P(3HPhV).While copolyesters P(3HPhV-co-3HDD)of 3-hydroxy-5-phenylvalerate(3HPhV)and 3-hydroxydodecanoate(3HDD)were synthesized when the strain was grown on mixtures of PVA and dodecanoic acid(DDA).Compositions of 3HPhV in P(3HPhV-co-3HDD)were controllable ranging from 3%to 32%depending on DDDA/PVA ratios.Nuclear magnetic resonance(NMR)spectra clearly indicated that the polymers were homopolymer of P(3HPhV)and random copolymers of 3HPhV and 3HDD.Their mechanical and thermal properties varied dramatically depending on the monomer ratios.Our results demonstrated the possibility to produce tailor-made,novel functional PHA using the chromosome edited P.entomophila.  相似文献   
10.
长江流域水牛血液蛋白多态性研究   总被引:12,自引:1,他引:11  
采集长江流域德昌、涪陵、江汉、滨湖和海子5个水牛地方品种共416 头牛的血样。电泳检测血红蛋白、血清运铁蛋白多态性,估算各等位基因频率及基因型频率,根据Hb及Tf两个位点的基因频率进行聚类分析。结果表明,5个水牛地方品种间遗传变异较小,其亲缘关系较近。  相似文献   
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