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81.
Glycogen storage diseases or glycogenoses are inherited diseases caused by abnormalities of enzymes that regulate the synthesis or degradation of glycogen. Deleterious mutations in many genes of the glyco(geno)lytic or the glycogenesis pathways can potentially cause a glycogenosis, and currently mutations in fourteen different genes are known to cause animal or human glycogenoses, resulting in myopathies and/or hepatic disorders. The genetic bases of two forms of glycogenosis are currently known in horses. A fatal neonatal polysystemic type IV glycogenosis, inherited recessively in affected Quarter Horse foals, is due to a mutation in the glycogen branching enzyme gene ( GBE1 ). A second type of glycogenosis, termed polysaccharide storage myopathy (PSSM), is observed in adult Quarter Horses and other breeds. A severe form of PSSM also occurs in draught horses. A mutation in the skeletal muscle glycogen synthase gene ( GYS1 ) was recently reported to be highly associated with PSSM in Quarter Horses and Belgian draught horses. This GYS1 point mutation appears to cause a gain-of-function of the enzyme and to result in the accumulation of a glycogen-like, less-branched polysaccharide in skeletal muscle. It is inherited as a dominant trait. The aim of this work was to test for possible associations between genetic polymorphisms in four candidate genes of the glycogen pathway or the GYS1 mutation in Cob Normand draught horses diagnosed with PSSM by muscle biopsy.  相似文献   
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试论野生稻资源遗传多样性原生境保存   总被引:1,自引:0,他引:1  
我国野生稻资源丰富,分布地域广阔,由于经济建设用地需要,近年来野生稻原生地遭到严重破坏,野生稻原生境保存已是十分紧迫的事情。本文论述了原生境保存的意义,原生境保存地的选择原则及设想,旨在提高全民生态保护意识,加强野生稻资源保护。  相似文献   
84.
We compared the genetic diversity and distance among six German draught horse breeds to wild (Przewalski's Horse), primitive (Icelandic Horse, Sorraia Horse, Exmoor Pony) or riding horse breeds (Hanoverian Warmblood, Arabian) by means of genotypic information from 30 microsatellite loci. The draught horse breeds included the South German Coldblood, Rhenish German Draught Horse, Mecklenburg Coldblood, Saxon Thuringa Coldblood, Black Forest Horse and Schleswig Draught Horse. Despite large differences in population sizes, the average observed heterozygosity (H(o)) differed little among the heavy horse breeds (0.64-0.71), but was considerably lower than in the Hanoverian Warmblood or Icelandic Horse population. The mean number of alleles (N(A)) decreased more markedly with declining population sizes of German draught horse breeds (5.2-6.3) but did not reach the values of Hanoverian Warmblood (N(A) = 6.7). The coefficient of differentiation among the heavy horse breeds showed 11.6% of the diversity between the heavy horse breeds, as opposed to 21.2% between the other horse populations. The differentiation test revealed highly significant genetic differences among all draught horse breeds except the Mecklenburg and Saxon Thuringa Coldbloods. The Schleswig Draught Horse was the most distinct draught horse breed. In conclusion, the study demonstrated a clear distinction among the German draught horse breeds and even among breeds with a very short history of divergence like Rhenish German Draught Horse and its East German subpopulations Mecklenburg and Saxon Thuringa Coldblood.  相似文献   
85.
西双版纳傣族利用野生蔬菜种类变化及原因分析   总被引:1,自引:0,他引:1  
运用民族植物学的方法,选择西双版纳自然及社会经济发展不同的三个傣族村寨曼安、曼伞和曼广囡为研究对象,调查当地村民利用野生蔬菜情况,并探讨利用种类变化的原因。三个傣族村寨村民利用的野生蔬菜有228种,分属于75个科,其中曼安村寨147种,曼伞村寨144种,曼广囡村寨105种。通过Multivariate方差分析(P<0.05)表明:不同村寨的村民平均每人提及的野生蔬菜物种数存在显著差异;年轻组平均每人提及的野生蔬菜物种数明显低于年长组,不同性别之间差异不显著;野生蔬菜知识的流失在男性之间比女性更为严重。最后对影响野生蔬菜利用的因素,野生蔬菜利用变化的原因以及传统野生蔬菜知识的流失进行了分析,就如何保护传统知识进行了探讨。  相似文献   
86.
Summary The objectives of this study were to determine if biotin-labelled total genomic DNA of rye (Secale cereale L.) could be used to (i) preferentially label rye meiotic chromosomes in triticale and (ii) detect translocation stocks at interphase and/or early prophase by in situ hybridization. Welsh triticale, a wheat-rye segmental amphiploid, and Kavkaz wheat, a wheat-rye translocation were used. The results indicated that labelled chromosomes of rye and unlabelled chromosomes of wheat could be observed throughout all meiotic stages in the triticale. For Kavkaz wheat, the presence of the translocated 1RS chromosome arm of rye was detected at the interphase or very early prophase stage. Rapid assessment of feasibility of gene transfers and detection of alien DNA in somatic cells at the interphase stage by in situ hybridization allows for rapid decision-making and saves time and expense in plant breeding programs.Plant Research Centre Contribution No. 1276  相似文献   
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繁殖是植物种群更新与维持的重要环节。包括极小种群野生植物在内的受威胁物种, 其濒危原因是在长期演化过程中自身繁育力的衰退、生活力的下降等内在因素和人类的过度采挖和生境的破坏等外在因素共同作用的结果。对极小种群野生植物进行高效的人工繁殖, 能扩大种群数量并应用于迁地保护、自然回归和满足商品市场的需求, 有利于其种质资源的保护和可持续利用。为了保持物种的遗传多样性, 采用种子繁殖育苗是有效的方法, 扦插、嫁接和组织培养技术等无性繁殖方法则可用于对难以用种子繁殖的种类进行快速繁殖。本文对14种中国典型极小种群野生植物的繁殖特性和已有的人工繁殖方法进行了综述, 并简要介绍在其种苗繁殖研究方面取得的进展。其中利用播种繁殖成功的物种有12种, 共繁殖230,000株种苗; 利用扦插繁殖成功的物种有5种, 共繁殖33,100株种苗; 华盖木(Manglietiastrum sinicum)、河北梨(Pyrus hopeiensis)和黄梅秤锤树(Sinojackia huangmeiensis)采用嫁接繁殖出了2,415株种苗; 9个物种的组织培养技术获得成功, 共繁殖了24,850株种苗。这些种苗有些已应用于迁地保护和自然回归。上述研究结果为这14种极小种群野生植物的保护和利用提供了理论和技术基础, 也能为其他极小种群野生植物的保护和利用提供参考。  相似文献   
89.
A total of 111 rhizobial strains were isolated from wild legumes in Xinjiang, an isolated region of northwest China. Nine genomic species belonging to four genera of Rhizobium, Mesorhizobium, Ensifer, and Bradyrhizobium were defined among these strains based on the characterization of amplified 16S ribosomal DNA restriction analysis (ARDRA), restriction fragment length polymorphism (RFLP) analysis of 16S-23S rDNA intergenic spacers (IGS), 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). Twenty-five nodC types corresponding to eight phylogenetic clades were divided by RFLP and sequence analysis of the PCR-amplified nodC gene. The acid-producing Rhizobium and Mesorhizobium species were predominant, which may be related to both the local environments and the hosts sampled. The present study also showed the limitation of using nod genes to estimate the host specificity of rhizobia.  相似文献   
90.
Glutaminase plays a critical role in the generation of glutamate, a key excitatory neurotransmitter in the CNS. Excess glutamate release from activated macrophages and microglia correlates with upregulated glutaminase suggesting a pathogenic role for glutaminase. Both glutaminase siRNA and small molecule inhibitors have been shown to decrease excess glutamate and provide neuroprotection in multiple models of disease, including HIV-associated dementia (HAD), multiple sclerosis and ischemia. Consequently, inhibition of glutaminase could be of interest for treatment of these diseases. Bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES) and 6-diazo-5-oxo-l-norleucine (DON), two most commonly used glutaminase inhibitors, are either poorly soluble or non-specific. Recently, several new BPTES analogs with improved physicochemical properties were reported. To evaluate these new inhibitors, we established a cell-based microglial activation assay measuring glutamate release. Microglia-mediated glutamate levels were significantly augmented by tumor necrosis factor (TNF)-α, phorbol 12-myristate 13-acetate (PMA) and Toll-like receptor (TLR) ligands coincident with increased glutaminase activity. While several potent glutaminase inhibitors abrogated the increase in glutamate, a structurally related analog devoid of glutaminase activity was unable to block the increase. In the absence of glutamine, glutamate levels were significantly attenuated. These data suggest that the in vitro microglia assay may be a useful tool in developing glutaminase inhibitors of therapeutic interest.  相似文献   
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