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141.
一种快速简单高效提取植物DNA的方法   总被引:2,自引:1,他引:2  
在综合分析多种提取植物DNA方法的基础上,改良发展了一种快速简便高效的DNA抽提方法.以多种植物的子叶、叶片以及愈伤组织为材料,采用本方法进行抽提纯化,得到的DNA质量好、得率高,且提取过程简单,适合于大批量快速提取植物DNA.  相似文献   
142.
中国榛属植物DNA提取与SSR初步分析   总被引:5,自引:0,他引:5  
为了探讨适合中国榛属植物基因组DNA的提取方法,分析榛属植物的遗传多样性,本实验以榛属植物的叶片为试材,通过对Doyle和Doyle方法的改良,摸索出适于中国榛属植物基因组DNA提取的方法,并以核酸产量、纯度、片断分布情况等指标来评价,获得高质量基因组DNA;同时应用4对欧榛SSR引物对中国榛属植物进行了跨种转移,并对具有商业潜力的平榛、毛榛和川榛3个种的遗传多样性进行了初步评价,4对引物从3个种的29个样本中扩增出33个等位基因,位点拥有的等位基因数量在6~12个之间,位点平均等位基因数为8.38.上述结果表明SSR是用于榛属种间育种、品种鉴定以及种间遗传图构建的有力工具.  相似文献   
143.
《Journal of Natural History》2012,46(13-16):925-936
Morphological and genetic data for the Iberian golden‐striped salamander, Chioglossa lusitanica, demonstrate the existence of two groups with southern and northern ranges, connected by a zone of intergradation in central Portugal. Because reproductive isolation between them is incomplete we consider the groups to be subspecies. The type locality of C. lusitanica (Buçaco near Lousã) is situated inside the mixed zone. This necessitates identification of the nominotypical subspecies. We sequenced a fragment of mitochondrial DNA from one of the species' syntypes and we determined what position over a latitudinal transect maximizes the morphological discrimination between the groups. Both approaches indicate that C. lusitanica from Buçaco represents the southern subspecies. A new subspecies of C. lusitanica is described from a northern locality (Valongo near Porto in north‐western Portugal). A lectotype is designated for Chioglossa lusitanica.  相似文献   
144.
《Journal of Natural History》2012,46(39-40):2585-2591
In the present study, the cloning and sequence analysis of interleukin‐6 (IL‐6) from the giant panda (Ailuropoda melanoleuca) were described. Sequencing revealed that IL‐6 complementary DNA contains a 636 base‐pair open reading frame encoding 211 amino acids. Homology analyses indicated that the identity levels of nucleotide and deduced amino acid sequences of IL‐6 between the giant panda and other species in Carnivora ranged from 90.5% to 85.6% and from 82.9% to 76.5%, respectively. Phylogenetic analyses based on nucleotide and amino acid sequences showed that the harbour seal shared a closer relationship with the giant panda than other carnivores (ursids not included). The functionally important domains and sites that have previously been recognized in other carnivores were all observed in the IL‐6 sequence of the giant panda. These findings suggest that the complementary DNA fragment cloned is indeed the IL‐6 molecule with biological activity and can be used in immunological studies of the giant panda.  相似文献   
145.
146.
Within a honeybee population, due to polyandry, there are supersister and halfsister relations, thus many subfamilies exist. For the Chinese honeybee (Apis cerana cerana F.) a phylogenetic dendrogram has been constructed in which 4 subfamilies are clustered based on DNA fingerprint patterns. And it has been observed that each kind of workers is distributed to several dierent sub-families.  相似文献   
147.
148.
《Journal of Natural History》2012,46(5-6):347-356
During a general malacological survey for freshwater gastropods in northern Patagonia, a population of Biomphalaria was encountered at Agua Escondida. Biomphalaria spp. are freshwater pulmonates of biomedical importance, uncommon in Mendoza Province, and often act as intermediate hosts for Schistosoma mansoni. By looking at both morphological and molecular characters, we describe a detailed process of identification and characterization of Biomphalaria peregrina from a location towards the extremity of its species range. A reference DNA ‘barcode’ is presented. As B. peregrina has been shown to be a permissive experimental host of S. mansoni, snails were also screened in the field for schistosomiasis and later in the laboratory using a novel polymerase chain reaction-based assay but no infections were found. Considering the transmission potential of this species, increased vigilance for intestinal schistosomiasis is recommended, especially if local environmental conditions become favourable for disease transmission, for example, through future climate change and intensification of irrigation.  相似文献   
149.
用7种限制性内切酶(BamHⅠ、BglⅡ、EcoRⅠ、EocRⅤ、PstⅠ、SacⅠ、XbaⅠ)分析了蛋鸭(金定鸭、莆田黑鸭)、野鸭(斑嘴鸭、绿头鸭)的mtDNA限制性类型,并用双酶法构建了以上鸭类的mtDNA限制性酶切图谱.结果表明,蛋鸭与野鸭在mtDNA结构上发生了明显分岐.比较两种野鸭和金定鸭的图谱,发现金定鸭与绿头鸭的亲缘关系较近.  相似文献   
150.
一种家猪基因组PCR—RAPD反应体系的建立   总被引:1,自引:0,他引:1  
以家猪血样为DNA提取材料 ,建立了用改进方法提取DNA为模板进行PCR-RAP 分析的最佳条件,获得稳定而理想的PCR-RAPD扩增结果。  相似文献   
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