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Genetic mapping provides a powerful tool for quantitative trait loci (QTL) analysis at the molecular level. A simple sequence repeat (SSR) genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton (Gossypium hirsutum L.) cultivars, namely TM-1 and Hai 7124 (G. barbadense L.), were used to map and analyze QTL using the composite interval mapping (CIM) method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds (LOD)≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection (MAS) of these traits in tetraploid cotton breeding.  相似文献   
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INTRODUCTIONEstrogen has been known to exert extensive effects via estrogen receptor (ER) on diverse physio-logical and develoPmental functions of the brain[1,2]. It has been observed that the distribution ofthe classical ER subtype-a (ERa) and the recentlycharacterized novel ER subtype--fi (ERg), and theirexpression patterns (ERcr/ERfi) vary greatly amongvarious brain regions[1, 3]. These evidences suggestthat each ER subtype may play a different role inestrogen's effects on the br…  相似文献   
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The angiotensin Ⅱ type 1 receptor and receptor-associated proteins   总被引:1,自引:0,他引:1  
INTRODUCTIONThe renin-angiotensin system (RAS) is consid-ered to be the major regulator of blood pressure)electrolyte balance and renal, neuronal as well as en-docrine functions related to cardiovascular control.The RAS is the key factor in most cases essential hy-pertension, as indicated by successes in treatment ofhypertensive patients with various angiotensin I con-verting enzyme (ACE) inhibitors and receptor block-ers. Renin was a central subject of intense investigation because of…  相似文献   
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INTRODUCTIONHepatitis B virus (HBV) infection is the mostcommon viral infection in humans especially inChina and East Asia. At present, the most effi-cient method to control the disease is vaccinationof new-borns. Both blood derived vaccine and re-combinant vaccine are hepatitis B surface alltigen(HBsAg)-based and useful in the prevention of thedisease[1-3]. HBsAg could evoke protective humoralimmune response in vivo, but the immune memoryonly last for 5 years or so[3, 4]. How to des…  相似文献   
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棕黑锦蛇赤峰亚种染色体组型、C带和Ag-NORs研究   总被引:5,自引:0,他引:5  
以骨髓细胞为材料研究了棕黑锦蛇赤峰亚种的染色体, 结果表明,该物种的2n=36,由8对大型的和10对微小的染色体组成,AF=50。No.4为性染色体(ZW型);所有大型染色体均显示端粒深染C带,但仅NO.2、3、5和Z染色体显示着丝粒浅染C带。W染色体为整条C带阳性;该物种一对NOR分布于微小染色体。锦蛇属核型可能经历过染色体间的着丝粒融合的罗伯逊易位。 Abstract:This paper reports the karyotype,C-bands and Ag-NORs of Elaphe schrenckii anomala(Boulenger).The diploid number,2n=36,comprising 8 pairs of macro- and 10 pairs of microchromosomes in the E.s.anomala.AF=50.The No.4 is sex chromosome,which belong to ZW type.The C-banding technique revealed telomeric constitutive heterochromatin in the whole macrochromosome.But the centromeric C band was only observed in No.2,3,5 and Z chromosome,while a whole W chromosome is constitutive heterochromatinization.Two NORs was observed in group of microchromosome.  相似文献   
17.
早籼稻碾磨品质品种、地点、品种×地点互作效应的研究   总被引:7,自引:2,他引:5  
以浙江省1995年早籼稻品种区域试验6个试点参试品种碾磨品质测定结果为试验材料,用多元分析法探讨了糙米率、精米率、整精米率3个碾磨品质的品种(基因型)、地点、品种×地点互作效应和各效应内碾磨品质间的相关关系,进行了参试品种互作效应检验。分析结果表明,糙米率、精米率以品种效应为主,整精米率性状以环境效应最大。相关分析显示,糙米率、精米率呈较强正相关,糙米率、精米率与整精米率均无相关关系。参试品种互作效应检验显示,多数品种整精米率均存在基因型×地点交互作用,糙米率、精米率多数品种较稳定。 Abstract:The genotype,test site,genotype×site effects on brown rice rate,milled rice recovery and head rice recovery as well as the correlation coefficients between the milling qualities within various effects were approached by using multiple analysis method with the data collected from early season indica rice varieties tested in regional trial in Zhejiang Province.Results showed that brown rice rate,milled rice recovery were predominantly affected by genotype.While head rice recovery was mostly conditioned by environment effect.Correlation analysis displayed that there were positive correlation between brown rice rate and milled rice rate.However,no correlation between brown rice rate,milled rice recovery and head rice recovery was found.The analysis of genotype×site of the varieties tested displayed that head rice recovery of the most tested varieties is involved with the interaction effects between the two components,while brown rice rate,milled rice recovery of the most tested varieties were more stable.  相似文献   
18.
利用聚合酶链反应和荧光(6-FAM)自动化检测技术对广东地区汉族106例无亲缘关系样本进行MICA基因外显子5和MICB基因内含子1微卫星基因座多态性及其单体型分布调查。根据群体资料估算两者间的单体型频率、连锁不平衡参数、相对连锁不平衡参数。结果显示,广州地区汉族人群MICA和MICB微卫星基因座基因型分布符合Hardy-Weinberg平衡法则,共检出MICA微卫星基因座 5个等位基因, MICB微卫星基因座14个等位基因。其中MICA A5基因频率最高(0.2877),A4基因频率最低(0.1321)。MICB CA14等位基因频率最高(0.3255),CA19、CA28等位基因频率最低(0.0047),未检出CA27。21种MICA-MICB单体型频率大于1%(连锁不平衡参数>0), 其中单体型A5-CA14 (16.73%), A5.1-CA18 (8.75%), A4-CA26(3.76%),A9-CA15(3.66%)和A6-CA21(2.61%)为强连锁常见单体型(χ2>3.84, P<0.05)。广州地区汉族人群MICA和MICB微卫星基因座多态性和单体型分布有其自身特点,MICA和MICB微卫星基因座适合做为遗传标志,用于人类学、遗传疾病基因连锁分析、法医学亲子鉴定和个体识别等研究领域。Abstract: This study is to investigate genetic polymorphisms and haplotypes of microsatellite locus in the exon 5 of the MICA gene and intron 1 of the MICB gene based on 106 samples of Guangzhou Han Population by polymerase chain reaction and fluorescent technique (6-FAM). The corresponding haplotype frequencies, linkage disequilibria values and relative linkage disequilibria values were estimated based on population data. The results show that the genotype distributions of MICA and MICB microsatellite meet Hardy-Weinberg equilibrium in Guangdong Han population. In total, 5 alleles of MICA microsatellite locus and 14 alleles of MICB microsatellite locus were observed. MICA A5 was the most common allele (0.2877), whereas A4 was the least popular one (0.1321). MICB CA14 was the most common allele (0.3255), and CA19 and CA28 were the least popular ones (0.0047). CA27 was not observed. Twenty-one kinds of MICA-MICB haplotypes occurred at frequencies of more than 1% (linkage disequilibria value>0). The common MICA-MICB haplotypes were A5-CA14(16.73%), A5.1- CA18 (8.75%), A4- CA26(3.76%),A9-CA15(3.66%) and A6-CA21(2.61%)(χ2>3.84, P<0.05), and they were strong linkage disequilibria. The polymorphisms and haplotypes distributions of MICA and MICB microsatellite locus in Guangzhou Han population have their own genetic characteristics. The microsatellite locus of the exon5 of the MICA gene and intron 1 of the MICB gene could be used as the genetic markers in the studies of anthropology, linkage analysis of genetic disease genes, individual identification and paternity test in forensic medicine.  相似文献   
19.
一种简便、快速的大肠杆菌质粒转化方法   总被引:2,自引:0,他引:2  
将受体菌与质粒DNA混匀直接在Ca2+离子选择平板上进行转化和筛选,其转化过程仅需2 min左右,并能得到105以上的转化效率, 可满足一般克隆工作的需要。 Abstract:After mixing the recipient cells and plasmids DNA, directly spread the mixture on selective media containing Ca2+. The whole process of transformation just needs 2 min or so, and could acquire the transformation efficiency of more than 105, which is enough to common gene cloning.  相似文献   
20.
Bacillus thuringiensis (Bt), a Gram-positive bacte-rium, produces insecticidal crystal proteins during sporulation. Bt has been used as biopesticides to con-trol a number of insect pests from Lepidoptera, Dip-tera and Hymenoptera and also has become so far the leading gene sources of transgenic plants resistant toinsect pests[1,2]. In China, the use of Bt cotton began in 1997 in Hebei, Shandong and Henan provinces, etc. and rapidly increased to more than 2 million ha in 2002, which is effe…  相似文献   
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