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1.
O.S.S浅谈     
Oncology Support System是荷兰PHI LIPS公司O.S.S的全称。这是一台在Treatment Planning System(T.P.S治疗计划系统)基础上发展而成、辅助CT诊断、设计三维放射治疗的专用计算机系统。我院放射治疗科于84年完成了SL 75—20医用电子直线加速器、模拟定位机、O.S.S等设备的安装  相似文献   

2.
通过遗传转化和转导分析及核糖体蛋白质的双向凝肢电泳分析结果,表明编码枯草杆菌168核糖体30S小亚基五个核糖体蛋白质S3、S5、S7、S12和S17的基因顺序是rpsL-rpsC-rpsQ-rpsE-rpsG。  相似文献   

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4.
大麦45S和5S rDNA定位及5S rDNA伸展纤维的FISH分析   总被引:7,自引:1,他引:6  
用荧光原位杂交技术对45S和5SrDNA在大麦(Hordeum vulgare L.)有丝分裂中期染色体进行了确定分析,较强的45SrDNA信号共有2对,分别分布在大麦的第1染色体的短臂和第2染色体的长臂。而5SrDNA则只有1对杂交信号,位于第3染色体的长臂,但信号较弱。用伸展DNA纤维的荧光原位杂交(Fiber—FISH)技术测定了5SrDNA在大麦的基因组中的拷贝数,计算出5SrDNA的拷贝数约为408~416。对大麦品种中rDNA位点数目的可变性进行了讨论。  相似文献   

5.
【目的】小毛瓢虫属Scymnus Kugelann昆虫主要捕食蚜虫、蚧虫等害虫,是一类经济上重要的天敌昆虫。目前针对小毛瓢虫属的系统发育研究尚属空白,亚属之间的系统演化关系尚不明确,为了建立合理的分类系统,亟需对小毛瓢虫属的亲缘关系进行研究和探讨。【方法】以华南农业大学馆藏的小毛瓢虫属5亚属共44种为研究对象,采用PCR技术对12S, 16S和28S rRNA基因的部分序列进行扩增;运用MEGA 7.0分析了小毛瓢虫属内12S, 16S和28S rRNA基因的碱基组成,基于K2P模型计算了小毛瓢虫属44种的种间遗传距离;采用最大似然法(maximum-likelihood, ML)和贝叶斯推断法(Bayesian-inference, BI)构建该属的系统发育树。【结果】扩增获得小毛瓢虫属44种的12S rRNA基因序列平均长度为356 bp, 16S rRNA基因序列平均长度为351 bp, 28S rRNA基因序列平均长度为315 bp;序列分析表明,12S rRNA基因的A, T, G和C平均含量分别为38.8%, 43.5%, 11.9%和5.8%, 16S rRNA基因的A, T, G和C平均含量分别为37.6%, 40.3%, 14.4%和7.7%, 28S rRNA基因的A, T, G和C平均含量分别为26.7%, 18.3%, 31.4%和23.5%;基于联合序列分析的种间遗传距离为0.004~0.276,平均遗传距离为0.115。系统发育分析结果表明,小毛瓢虫属为单系起源,而小毛瓢虫亚属Scymnus(Scymnus) Kugelann、毛瓢虫亚属Scymnus(Neopullus) Sasaji、小瓢虫亚属Scymnus(Pullus) Mulsant和拟小瓢虫亚属Scymnus(Parapullus) Yang均为并系起源。【结论】基于12S, 16S和28S rRNA基因序列的小毛瓢虫属系统发育分析显示传统的形态学分类体系与基于分子数据分析的结果部分不一致,这表明应该对该属内各亚属的鉴别特征进行全面检视,筛选并确立各亚属的形态指标,同时也表明该属内的亚属分类单元需重新厘定。  相似文献   

6.
Ohne Zusammenfassung  相似文献   

7.
短杆菌肽S的研究进展   总被引:2,自引:0,他引:2  
短杆菌肽S是迄今为止研究得最详细的一种与细胞膜发生相互作用的环状肽类抗生素.它的作用机理是破坏细胞膜结构,导致细胞内含物的释放,而最终引起细胞的死亡.对短杆菌肽S的研究进展进行了综述.  相似文献   

8.
蓖麻蚕的核糖体核糖核酸(rRNA)的基因(rDNA)是多拷贝基因,其重复单位成线性方向排列。在每一重复单位中含有18S、28S和5.8S rRNA基因各一个。了解它们的排列状况是认识rDNA结构的基础。本文将无性繁殖的该rDNA用各种限制性内切酶水解后,制成Southern转移膜与放射性同位素标记的18S、28S和5.8S rRNA杂交;又将18S和28S rRNA制成Northern转移膜与放射性同位素标记的rDNA片段杂交,从而排出18S、28S和5.8S rRNA基因在rDNA上面的相对位置。  相似文献   

9.
S100、S100α和S100β蛋白在乳腺癌中的表达及诊断意义   总被引:7,自引:0,他引:7  
为了探讨S100 蛋白在乳腺癌表达的临床病理意义,采用S-P免疫组化法,检测了S100 和S100α、S100β和Actin 在112 例乳腺癌组织中的表达情况。发现S100 和S100α在癌旁正常小叶和导管的肌上皮细胞中有明显表达, S100β无表达。3 种蛋白均可在癌细胞中表达, 表达的阳性率分别为82.06% 、57.94% 和60.74% , S100 表达率明显高于S100α和S100β(X2= 14.17, P< 0.01)。Actin 阳性率为25.89% , 明显低于三种S100 蛋白(X2= 29.85, P< 0.0001)。三种S100蛋白的表达均与乳腺癌核分裂数、组织分级和淋巴结转移均无明显关系。研究显示乳腺癌S100 蛋白的表达不表明有肌上皮分化, S100 可作为乳腺癌的一种标志蛋白  相似文献   

10.
分离肠道病原菌的培养基种类繁多,但效果却不一致,其中效果较满意者当推3号胆盐S.S.琼脂及去氧胆酸钠-牛胆酸钠琼脂(简称郑氏S.S.琼脂)。我院试用的洗衣粉-去氧胆酸钠琼脂(简称洗衣粉S.S.琼脂)效果又较前者为优,这种培养基对肠道病原菌不但有很高的阳性检出率,而且痢疾杆菌在这种培养基上呈特殊的粘性菌落,可以在分离培养基上初步鉴别痢疾菌和沙门氏菌菌落,使肠道培养基更趋于完善。  相似文献   

11.
Identification of S-genotypes by PCR-RFLP in breeding lines of Brassica.   总被引:4,自引:0,他引:4  
We developed a molecular method for the identification of the S-alleles of Brassicaceae, which belongs to the inbred line. This method is quicker and more precise than the existing methods. The genotype of the S-allele for 20 S-haplotypes of cabbage and 20 S-haplotypes of broccoli was determined by a pollination test. In order to identify the S-alleles, we performed PCR-RFLP with a mixture of the primers that are related to the S-locus glycoprotein (SLG) gene, which corresponds to the results of the pollination test. The selected primers amplified all of the single bands of about 1,150 bp in all 40 lines of cabbage and broccoli. Three out of 20 lines of cabbage were amplified by class I SLG specific primers, whereas all of the lines of the cabbage were amplified by class II SLG specific primers. Therefore, we could not classify class I and class II precisely by the class I and class II primers. However, 15 out of 20 lines of broccoli were amplified by the class I SLG specific primers. The remaining 5 lines were amplified with the class II SLG specific primers. We then digested the amplified PCR products with various restriction endonucleases and chose a restriction endonuclease, which accords exactly with the results of the diallel cross. The best one was HinfI. Its RFLP result was the same as that of the nucleotide sequence analysis. The 40 lines of cabbage and broccoli consisted of 16 different S-haplotypes. Therefore, the PCR-RFLP analysis was quicker and more precise in identifying the characteristics of S-haplotypes that are used in breeding. Also, we were able to check whether the lines could be mixed. The S-genotypes were difficult to determine due to the different flowering time.  相似文献   

12.
芸薹属的自交不亲和性是受单基因座、复等位基因控制的孢子体控制型。自交不亲和基因座位(S-locus)是由多个基因组成的复杂区域,称之为S多基因家族,其大多数成员分布于芸薹属的整个染色体组。目前已鉴定出100多个S等位基因,它们的起源分化始于一千万年前。S-座位上存在的多基因有3种:SRK,SLG和SCR/SP11;SRK和SLG在柱头中表达,SCR/SP11在雄蕊中表达。SRK蛋白在识别同类花粉的过程中起主要作用,而SLG蛋白增强了这种自交不亲和反应。SLG与SRK基因中编码S-结构域的核苷酸序列相似性程度高达85%~98%。基因转换可能是SLG和SRK的高度同源性能够得以保持的原因。SRK,SLG和SCR基因紧密相连,并表现出高水平的序列多样性。SRK与SLG基因间的距离很近,在20~25 kb之间。在柱头和花粉中,自交不亲和等位基因之间的共显性关系要比显性和隐性关系更加普遍,这是芸薹属自交不亲和性的一大特点。自交不亲和基因的进化模式存在两种假说:双基因进化模式和中性变异体进化模式;可能存在几种不同的进化方式,它们共同在自然群体中新的S等位基因进化过程中起作用。  相似文献   

13.
RFLP analysis of a cDNA probe SLG6, governing self incompatibility (SI) in Brassica oleracea, using a recombinant inbred population of Brassica campestris followed by genetic linkage analysis led to the detection of two marker loci, SLG6a and SLG6b controlling SI. SLG6a was mapped in linkage group (LG) 9 and was flanked by the RFLP markers ec4f10 (6.4 cM) and wg5b9 (4.2 cM). SLG6b positioned in LG 2 and was flanked by the RFLP markers wg2d11 (9.9 cM) and ec4e7 (26.9 cM). These results indicated the scope of marker-aided introgression of these genes into self-compatible genotypes for production of SI lines suitable for hybridization in B. campestris. Comparative mapping of LG 9 containing SLG6b with corresponding linkage groups of B. oleracea (BO 2) and B. napus (BN 16) led to the detection of small homologous regions with SLG6 locus linked with another RFLP locus. This evidenced for homology of the SLG genes across Brassica species and possibility of using any single cloned SLG gene for development of SI lines in any Brassica species.  相似文献   

14.
Self-incompatibility (SI) has been well studied in the genera Brassica and Arabidopsis, which have become models for investigation into the SI system. To understand the evolution of the SI system in the Brassicaceae, comparative analyses of the S-locus in genera other than Brassica and Arabidopsis are necessary. We report the identification of six putative S-locus receptor kinase genes (SRK) in natural populations of Capsella grandiflora, an SI species from a genus which is closely related to Arabidopsis. These S-alleles display striking similarities to the Arabidopsis lyrata SRK alleles in sequence and structure. Our phylogenetic analysis supports the scenario of differing SI evolution along the two lineages (The Brassica lineage and Arabidopsis/Capsella lineage). Our results also argue that the ancestral S-locus lacked the SLG gene (S-locus glycoprotein) and that the diversification of S-alleles predates the separation of Arabidopsis and Capsella.  相似文献   

15.
Thirty resynthesized Brassica napus lines with defined S-allele constitution and the ancestral B. oleracea and B. campestris lines were used for the analysis of S- locus glycoproteins (SLGs). The aim of this study was to investigate (1) whether the S-specific glycoproteins of the diploid ancestor lines were also expressed in the amphidiploid hybrids and (2) whether the occurrence of SLG bands was correlated with the activity of the respective S-alleles, which had been tested by means of diallele pollination tests in a previous study. Stigma proteins were separated by isoelectric focusing (IEF)-gel electrophoresis, and glycoprotein bands were identified by Western blotting and Con-A/peroxidase reaction. The SLG bands of the B. campestris parent could be detected in all 30 resynthesized B. napus lines. In contrast, B. oleracea SLG bands could only be detected in 12 resynthesized B. napus lines. Only B. napus lines which carried the dominant B. oleracea S-alleles S8 and S29 showed respective SLG bands in all cases. Nine B. napus lines showed only glycoprotein bands of the B. campestris parent, although the biological functioning of the B. oleracea S-alleles was demonstrated by test-pollinations. New SLG bands different from those of the B. oleracea and B. campestris parents occurred in 16 B. napus lines. The expression level of the SLGs in B. napus was not correlated with the self-incompatibility phenotype, not only in the case of recessive S-alleles (S2, S15), but also for dominant alleles (e.g. S14, S32, S45). Received: 22 January 1999 / Accepted: 30 January 1999  相似文献   

16.
17.
Polymorphism of the S-locus glycoprotein (SLG) and S-locus receptor kinase (SRK) genes in Raphanus sativus was analyzed by PCR-RFLP using SLG- and SRK-specific primers. Twenty four inbred lines of R. sativus could be grouped into nine S haplotypes. DNA fragments of SLG alleles specifically amplified from five S haplotypes by PCR with Class-I SLG-specific primers showed different profiles upon polyacrylamide-gel electrophoresis after digestion with restriction endonucleases. The five R. sativus SLG alleles were determined for their nucleotide sequences of DNA fragments. Comparison of the amino-acid sequences with a reported Brassica SLG (S6) showed 77-84% homology. Deduced amino-acid sequences showed 12-conserved cystein residues and three hypervariable regions which are characteristic of Brassicsa SLG. A DNA fragment was also amplified by PCR from two of each S haplotype with Class-II SLG-specific primers, and showed polymorphism when cleaved with restriction endonucleases. The nucleotide sequences of amplified DNA fragments of the Class-II SLG revealed about 60% similarity with those of the Class-I SLG. It is concluded that there exist both Class I and Class II S alleles in R. sativus, as in Brassica campestris and Brassica oleracea. PCR using SRK-specific primers amplified a DNA fragment of about 1.0 kb from seven of each S haplotype out of 24 tested. These DNA fragments showed high polymorphism in polyacrylamide-gel electrophoresis after digestion with restriction endonucleases. Nucleotide sequences of the DNA fragments amplified from the seven S haplotypes showed that the fourth and the fifth exons of SRK are highly conserved, and that there is high variation in the fifth intron, the sixth intron and seventh exon of the SRK which may be responsible for the polymorphic band patterns in PCR-RFLP analysis. The PCR-RFLP method has proven useful for the identification of S alleles in inbred lines and for listing S haplotypes in R. sativus. Phylogenic analysis of the SLG and SRK sequences from Raphanus and Brassica revealed that the Raphanus SLGs and SRKs did not form an independent cluster, but were dispersed in the tree, clustering together with Brassica SLGs and SRKs. Furthermore, SLGs and SRKs from Raphanus were both grouped into Class-I or Class-II S haplotypes. Therefore, these results suggest that the diversification of the SLG and SRK alleles occurred prior to the differentiation of the two genera Brassica and Raphanus.  相似文献   

18.
以小麦(Triticum aestivum L.)与高冰草(Agropyron elongatum(Host)Nevski)体细胞杂种同一个克隆来源的F2-F6自交系Ⅱ-2、Ⅱ-Ⅰ-8以及由Ⅱ-Ⅰ-8 F2分离形成的8-1(F3-F6)为材料,利用小麦叶绿体基因组的微卫星(Microsatellite)特异引物及随机扩增多态性DNA(RAPD)引物进行分析.结果表明,杂种株系的叶绿体基因组组成一致,均以小麦叶绿体基因组为主,仅在rpl14和rpl16基因的间隔序列中检测到双亲的特征带,表明有高冰草的叶绿体DNA在杂种中存在,并稳定遗传至第六代.RAPD分析表明,不同杂种株系中存在不同的高冰草核DNA片段,核基因组在传代中基本稳定.  相似文献   

19.
In Brassica species, self-incompatibility in the recognition reaction between self and non-self pollens is determined by two genes, SLG and SRK, at the S locus. We have cloned and characterized a genomic DNA fragment containing a complete open reading frame of the SLG gene from Chinese cabbage. The genomic clone, named BcSLG2, was found to possess the region that shares a homology of 77% in amino acid identity with the SLG46 gene of Brassica campestris. Northern blot analysis revealed that the BcSLG2 gene expression is restricted to the pistil of Chinese cabbage flower. In situ hybridization showed that in the pistil, the gene is expressed predominantly in the stigmatic tissue. Much lower expression in the tapetum was also detectable at an immature stage of the flower development. Southern blot hybridization with the BcSLG2 DNA probe showed polymorphism in the SLG gene organization of the Chinese cabbage plants. These results will provide valuable information in understanding the S gene complex of the Chinese cabbage plants.  相似文献   

20.
【目的】研究分离自四川攀枝花的银合欢根瘤菌的遗传多样性。【方法】采用联合16S rDNA RFLP和IGS RFLP的综合聚类分析(16S-IGS RFLP)、AFLP及多位点持家基因(16S rDNA,atpD,recA)序列的联合分析对供试银合欢根瘤菌进行研究。【结果】31株未知菌具有15种16S-IGS遗传图谱类型、27种AFLP类型。16S-IGS RFLP结果表明,没有未知菌与Bradyrhizobium的参比菌株聚在一起。在71.4%的相似水平上,31个未知菌按属的水平分成3个分支:S、M和R,分别分布在Sinorhizobium属(28株)、Mesorhizobium属(2株)和Rhizobium属(1株)。S分支的28个菌在84%的相似水平上,16S-IGS RFLP聚类图中构成3个群:群S1、群S2、群S3;在AFLP聚类图中构成9个AFLP群:S1–S9。多位点基因序列表明,代表菌株SCAU215、SCAU231分别与M.Plurifarium、R.huautlense亲缘关系最近。而分布于Sinorhizobium属SCAU222和SCAU228、SCAU213、SCAU216可能代表Sinorhizobium的3个新类群。【结论】攀枝花市银合欢根瘤菌遗传多样性丰富,分布于Sinorhizobium、Mesorhizobium和Rhizobium三个属,且优势类群为Sinorhizobium。  相似文献   

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