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121.
关于保护乡土建筑"真实性"原则的辨析   总被引:1,自引:0,他引:1  
真实性是世界保护文化遗产的原则。如何理解保护乡土建筑真实性原则的内涵,是实现古村镇真实性保护的前提。可以从三个方面来看:首先,从文化生态学的观点看,保护乡土建筑的真实性,即保护古村镇文化基因的完整与个性形态;其次,通过修旧如故所呈现的古村镇的真实,不是原生态的真实,而是群体记忆中历史的真实;第三,保护乡土建筑的真实性,包括如何处理传统建筑形态的完整保护与居民现代生活的关系。  相似文献   
122.
禽类的Mx蛋白具有抵抗禽流感病毒及水疱性口炎病毒(VSV)的功能,对禽类Mx蛋白基因进行研究具有重要意义。以白来航(White Loghorn,WLH)作为实验动物,获得Mx蛋白基因全长并对基因组结构进行分析并克隆测序获得了Mx基因所有外显子区(1-14exons),为研究Mx基因结构及多态性分析奠定了基础。  相似文献   
123.
GH3 基因家族是植物生长素早期响应基因家族之一.拟南芥 10个GH3 基因启动子序列分析表明:GH3 基因的转录起始位点一般在起始密码子上游65~145bp之内,TATA box大多分布在(-24)~(-40)bp区域.MDB和MatInspector分析显示,AtGH3 s基因的上游调控区域普遍存在组织和器官特异性表达元件、激素响应元件以及环境响应元件,表明GH3 基因的表达受到多因素调控;同时,基因芯片数据显示AuxREs对生长素的响应非常重要,但也可能存在其他的生长素响应元件.  相似文献   
124.
蒋明  郑君利 《台州学院学报》2009,31(3):44-48,56
根据GenBank发布的几丁质酶基因序列设计PCR引物,从叶片cDNA中克隆到了番茄几丁质酶基因,并命名为LeCHI,基因在NCBI中的登陆号为FJ849060。测序结果表明,LeCHI编码区全长为762 bp,编码253个氨基酸。RT-PCR检测表明,LeCHI基因在根、茎、叶和花蕾中均有表达。序列比对结果表明,LeCHI编码的氨基酸序列与同科的马铃薯、辣椒有较高的同源性。  相似文献   
125.
Spinal muscular atrophy (SMA) is a disorder characterized by degeneration of lower motor neurons and occasionally bulbar motor neurons leading to progressive limb and trunk paralysis as well as muscular atrophy. Three types of SMA are recognized depending on the age of onset, the maximum muscular activity achieved, and survivorship: SMA1, SMA2, and SMA3. The survival of motor neuron (SMN) gene has been identified as an SMA determining gene, whereas the neuronal apoptosis inhibitory protein (NAIP) gene is considered to be a modifying factor of the severity of SMA. The main objective of this study was to analyze the deletion of SMN1 and NAIP genes in southern Chinese children with SMA. Here, polymerase chain reaction (PCR) combined with restriction fragment length polymorphism (RFLP) was performed to detect the deletion of both exon 7 and exon 8 of SMN1 and exon 5 of NAIP in 62 southern Chinese children with strongly suspected clinical symptoms of SMA. All the 32 SMA1 patients and 76% (13/17) of SMA2 patients showed homozygous deletions for exon 7 and exon 8, and all the 13 SMA3 patients showed single deletion of SMN1 exon 7 along with 24% (4/17) of SMA2 patients. Eleven out of 32 (34%) SMA1 patients showed NAIP deletion, and none of SMA2 and SMA3 patients was found to have NAIP deletion. The findings of homozygous deletions of exon 7 and/or exon 8 of SMN1 gene confirmed the diagnosis of SMA, and suggested that the deletion of SMN1 exon 7 is a major cause of SMA in southern Chinese children, and that the NAIP gene may be a modifying factor for disease severity of SMA1. The molecular diagnosis system based on PCR-RFLP analysis can conveniently be applied in the clinical testing, genetic counseling, prenatal diagnosis and preimplantation genetic diagnosis of SMA. Project supported by the National Natural Science Foundation of China (No. J0710043), and the Natural Science Foundation of Zhejiang Province (No. 2007C33049), China  相似文献   
126.
从文化人类学的视角根据文化基因的词源、传播方式、特点,选取了课程内容的选择、课程实施、课程开发、课程生成四个角度对课程作了解读和阐释,以利于更好、更准确地理解课程观。  相似文献   
127.
128.
This article highlights new nutritional concerns or practices that may influence the adaptation to training. The discussion is based on the assumption that the adaptation to repeated bouts of training occurs during recovery periods and that if one can train harder, the adaptation will be greater. The goal is to maximize with nutrition the recovery/adaptation that occurs in all rest periods, such that recovery before the next training session is complete. Four issues have been identified where recent scientific information will force sports nutritionists to embrace new issues and reassess old issues and, ultimately, alter the nutritional recommendations they give to athletes. These are: (1) caffeine ingestion; (2) creatine ingestion; (3) the use of intramuscular triacylglycerol (IMTG) as a fuel during exercise and the nutritional effects on IMTG repletion following exercise; and (4) the role nutrition may play in regulating the expression of genes during and after exercise training sessions. Recent findings suggest that low doses of caffeine exert significant ergogenic effects by directly affecting the central nervous system during exercise. Caffeine can cross the blood–brain barrier and antagonize the effects of adenosine, resulting in higher concentrations of stimulatory neurotransmitters. These new data strengthen the case for using low doses of caffeine during training. On the other hand, the data on the role that supplemental creatine ingestion plays in augmenting the increase in skeletal muscle mass and strength during resistance training remain equivocal. Some studies are able to demonstrate increases in muscle fibre size with creatine ingestion and some are not. The final two nutritional topics are new and have not progressed to the point that we can specifically identify strategies to enhance the adaptation to training. However, it is likely that nutritional strategies will be needed to replenish the IMTG that is used during endurance exercise. It is not presently clear whether the IMTG store is chronically reduced when engaging in daily sessions of endurance training or if this impacts negatively on the ability to train. It is also likely that the increased interest in gene and protein expression measurements will lead to nutritional strategies to optimize the adaptations that occur in skeletal muscle during and after exercise training sessions. Research in these areas in the coming years will lead to strategies designed to improve the adaptive response to training.  相似文献   
129.
文章通过温度梯度驯化得到了一株适用于工业中高温生产酒精的工程菌——Z.mobilis基因工程菌。对该工程菌株进行温度、发酵起始pH、接种量、发酵周期以及添加营养盐的优化试验最终得到该工程菌株的最佳发酵工艺,即发酵温35℃,发酵起始pH 6.0,接种量为10.0%,发酵周期48h,添加营养盐10 mg/L是最佳发酵工艺。最佳发酵工艺下,酒精得率为94.0%,酒分9.5%(v/v)。  相似文献   
130.
与目前压电基因传感器技术和DNA计算理论相结合,设计了一种基于压电基因传感器DNA计算的方法,并把此方法应用到可满足性问题的解决上,详细论述了计算的过程,并编写程序模拟和验证算法的可行性。与以前的DNA计算方法相比,该方法具有运算和检测解的同时性,计算的准确性和并行性以及计算过程的连续性等优点,说明将传感器技术和DNA计算相结合的生物高科技技术,在DNA计算及其应用中有着巨大的使用价值。  相似文献   
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