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1.
Bluetongue (BT) is an infectious, non-contagious arthropod-borne disease that infects all ruminants, including sheep, cattle, deer, goats and camelids. Bluetongue virus (BTV) belonged to Reoviridae is ARN genome of 19 Kb. Twenty-six BTV serotypes have long been recognized, to be associated with severe disease in certain breeds of sheep, whereas cattle and goats are usually sub-clinically affected. Before 2004, BT was considered an exotic disease in Morocco, however, the first outbreak was observed in 2004 in sheep. This outbreak was caused by the isolated BTV-4. Two years later a BTV-1 emerged in Morocco. Both serotype 1 and serotype 4 circulated after 2007 across the country. The aims of the present work was to perform a serological study on sheep from different regions in Morocco in order to clarify the current BTV epidemiological situation and its evolution from 2009 to 2012, to determine the co-infection rate, and to confirm the possible circulation of other BTV Serotype mainly the BTV-8. All of 436 sera were tested by serum neutralization using reference strains. Results confirm the presence of BTV-4, BTV-1 and BTV-8. However, the present study report for the first time the emerging BTV-8 circulation in Morocco. Moreover, the founding reveal as well a higher co-infection rate in cattle compared to sheep.  相似文献   
2.
水稻单粒种子DNA的快速制备及PCR分析   总被引:1,自引:0,他引:1  
以水稻单粒种子为材料,用NaOH溶液抽提DNA,用于PCR分析,结果表明:该方法提取的DNA可以扩增出水稻中的目的基因,并适用于SSR分析。该方法提取DNA速度快,成本低,适合大批量种子DNA的提取。  相似文献   
3.
转基因抗虫棉与陆地棉种质间的杂种优势和配合力分析   总被引:3,自引:2,他引:3  
采用NCⅡ交配设计,对5份转基因抗虫棉、6份柱头外露种质资源和彩色棉等陆地棉优异亲本组配杂交,分析杂种F1的11个性状的杂种优势和配合力.结果表明,主要产量性状皮棉产量,超高优势的平均值为6.18%,16个组合具正向的杂种优势;中亲优势的平均值为37.41%,24个组合均具有正向的中亲优势;竞争优势的平均值为-15.19%,8个组合出现正向竞争优势.其它产量性状铃重、单株铃数的杂种优势最为明显.纤维品质性状、2.5%跨长、比强度和伸长率的竞争优势明显.高亲值、中亲值和低亲值与F1平均值的相关关系表明,多数性状F1代平均值与中亲值和低亲值相关性密切.经配合力分析,双价321、新棉33 B、HK-1、96-67、惠无3055和01 HN 06表现较显著的GCA效应;SCA效应显著的7个性状中,A 1×B 6、A 2×B 5、A 2×B 3等组合有7个性状的SCA效应为正值.  相似文献   
4.
采用根癌农杆菌LBA4404和EHA105介导,对海岛棉的茎尖再生体系及其转化影响因子进行了研究。茎尖培养与棉花体细胞胚胎发生相比,不同基因型的茎尖再生频率差异不明显;在9种不同的激素组合中,以6-BA0.5 mg/L NAA0.1 mg/L与1/2MSB5 IBA 0.1 mg/L对茎尖的再生效果较好;获得较高转化频率的海岛棉培养条件为:海岛苗茎尖在OD600值为0.6~0.8农杆菌菌液中感染20~30 min,共培养3 d后进行转接,在含有不同激素和抗生素的各类培养基中进行抑菌和筛选继代培养,选择压以50~150 mg/L梯度进行;农杆菌以EHA105菌株的转化效果较好;抗性苗用SDS-CTAB法提取其总DNA,进行PCR扩增检测,有7株PCR检测呈阳性反应。由此,初步证明外源抗虫基因已经进入到再生植株的细胞核中。  相似文献   
5.
通过对转BT基因棉田及常规棉田害虫的对比调查研究,并结合室内饲养,明确了山西省转BT基因棉田害虫的主要种类及其与常规棉田害虫发生规律的不同点,为新的生态条件下山西省棉田害虫综合治理提供了依据。  相似文献   
6.
A comparative study was carried out to determine the susceptibility of five different cell lines to pseudorabies virus (PRV), a herpes virus of pigs. The cell systems tested were swine testicle (ST), mink lung (ML), equine dermal (ED), porcine kidney (PK15), and bovine turbinate (BT) cells. Virus titers obtained were 104.88, 104.38, 103.75, 102.63, and 100.25 for ML, ST, PK15, BT and ED cells, respectively indicating that ML, ST, and PK15 are optimal cell lines for the growth of PRV whereas BT and ED are not very sensitive.  相似文献   
7.
油菜高效转化系统的研究   总被引:17,自引:1,他引:16  
林良斌  官春云 《作物学报》1999,25(4):447-450
以甘蓝型油菜湘油13为试验材料,运用子房注射法将BT毒蛋白基因导入油菜。在授粉后第20小时至第30小时用自制的微玻针从子房中部注射0.5~1.5μg外源DNA,以高达12.8%的频率获得抗卡那霉素植株。分子杂交分析证明BT毒蛋白基因已整合到油菜基因组中,转化频率为1.6%,表明子房注射法是一种有效、实用的油菜遗传转化方法。  相似文献   
8.
2.5%高氯·苏云金可湿性粉剂450-750 g·hm-2对小菜蛾防效优良,施药过程中未发现人畜中毒现象,时甘蓝安全,可以大面积推广.  相似文献   
9.
BT型粳稻不育系双九A的选育及其利用   总被引:5,自引:2,他引:5  
双九A由安徽省农科院水稻所用80—4A作母本,以优质粳稻品系双九作保持系,经多代回交转育而成的BT型优质粳稻不育系,2002年在海南陵水基地通过安徽省农科院组织的专家鉴定。群体不育株率100%,套袋自交不结实,花酚败育度为99.54%。异交性状佳,花时早,异交结实率50%以上。配合力强,已选配出双优4183、双优3402等优质高产晚粳新组合,应用前景广阔。  相似文献   
10.
Astaxanthin (AST) is a product made from marine organisms that has been used as an anti-cancer supplement. It reduces pontin expression and induces apoptosis in SKBR3, a breast cancer cell line. Using Western blotting and qRT-PCR analyses, this study revealed that in the T47D and BT20 breast cancer cell lines, AST inhibits expression of pontin and mutp53, as well as the Oct4 and Nanog cancer stem cell (CSC) stemness genes. In addition, we explored the mechanism by which AST eradicates breast cancer cells using pontin siRNAs. Pontin knockdown by pontin siRNA reduced proliferation, Oct4 and Nanog expression, colony and spheroid formation, and migration and invasion abilities in breast cancer cells. In addition, reductions in Oct4, Nanog, and mutp53 expression following rottlerin treatment confirmed the role of pontin in these cells. Therefore, pontin may play a central role in the regulation of CSC properties and in cell proliferation following AST treatment. Taken together, these findings demonstrate that AST can repress CSC stemness genes in breast cancer cells, which implies that AST therapy could be used to improve the efficacy of other anti-cancer therapies against breast cancer cells.  相似文献   
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