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1.
葡萄牙帝国在海外探险和扩张的过程中延伸了旧大陆的贸易航线,把新大陆和旧大陆连接成一个全球贸易网络。与此同时,葡萄牙帝国的武装贸易和垄断贸易模式也深刻地影响了早期近代世界贸易的运行。  相似文献   

2.
该研究分析了拟南芥9个β-淀粉酶家族基因(BAM1―BAM9)在cDNA和蛋白质上的同源性,分析了每个基因反映密码子使用特性的参数:GC含量、同义密码子第1~3位置中的GC含量、有效密码子数等.结果表明,拟南芥β-淀粉酶家族基因在密码子的使用特性上不存在的偏好性.Spss分析表明,ENc与GC3s%和GC%呈显著正相关(P〈0.05).拟南芥β-淀粉酶家族基因序列间的同源性差异较大,在cDNA和蛋白质序列上的基因同源性分别为41.6%~64.2%和29.4%~62.6%,其中,BAM5和BAM6间的同源性最高.  相似文献   

3.
陕西安康市城区方言老派、新派用词不同。本文从使用上的多对一、一对一、一对多以及构词方式等方面,描写分析了老派、新派的主要词汇差异及原因。  相似文献   

4.
Irish Catholic teaching sisters were major actors in the development of education systems in New World countries such as the United States, Canada, South Africa, Australia and New Zealand. Immigrants themselves, they faced a number of key challenges as they sought to adapt Old World cultural and educational ideas to the education of the immigrant Irish in a new cultural, religious and educational context. A close examination of the wide range of sources available in private archives and elsewhere offers unique insights into the challenges facing 10 Irish Dominican Sister Teachers as they journeyed from Ireland to Dunedin to found primary and secondary schools in the young colony of New Zealand. This article examines their responses to their early experiences and the part they played in the development of a viable Catholic education system in nineteenth-century New Zealand.  相似文献   

5.
作为20世纪最有影响的语言谱系分类学家,格林伯格应用多边比较法提出了“欧亚超级语系假说”。这一假说的争议,表面集中在形态证据是否实在、词汇证据是否可信,以及比较方法是否可靠,其深层原因却在于,传统历史比较和现代超级语系建构在观念、理论和方法上存在的一系列差别。无论是格林伯格还是其批评者都陷入了同样困境:就语言材料自身难以完全证明到底是同源相还是偶然相似。根据美洲原居民的来源研究成果,新大陆的居民来自旧大陆,新旧大陆语言上的远古同源是合情合理的,当然这并不意味着欧亚超级语系假说不需要再提供更可靠的语言比较证据。  相似文献   

6.
Duo Liu 《Reading and writing》2017,30(8):1813-1834
The present study investigated the influence of morphological structure information on the memorization of Chinese subordinate and coordinative compound words using the memory conjunction error paradigm. During the Study Phase, Hong Kong Chinese college students were asked to either judge the word class (Exp. 1, N = 25) or the orthographic structure (Exp. 2, N = 26) of a set of Chinese compound words (Old words). During the Test Phase, the participants were presented with half of the Old words that they had previously seen during the Study Phase and a set of New words, which shared or did not share morphemes with the Old words, and were asked to determine whether they had seen these words in the Study Phase. Half of the New words shared the same compounding structure with the Old words (either subordinate or coordinative) and the other half did not. The participants made more memory errors when both the Old words and the New words were coordinative compounds compared to situations in which the Old words and the New words were subordinate compounds or where the structures of the Old words and the New words were incongruent. The involvement of the processing of morphological structure information during word memorization was supported by the findings. The different characteristics of the two compounding structures were discussed and a morphological structure layer in the mental lexicon was proposed to interpret the results.  相似文献   

7.
五四运动是中国新民主主义革命的伟大开端,但并不意味着旧民主主义革命的终结.革命领导权是区分新旧民主主义革命的根本标志,国民大革命时期,是国共合作共同领导中国革命的独特的历史时期,是新旧民主主义革命的交替时期.1927年大革命失败后,国民党从总体上已转变为反革命的政党,中国共产党开始了独立领导中国革命的新时期,旧民主主义革命至此终结.  相似文献   

8.
基因重复是普遍存在的现象,与基因组进化密切相关,是基因组和遗传系统分化的重要推动力.目前针对原核基因组中蛋白质编码基因序列中的重复基因的系统研究还很少.本文以四种具有不同GC%含量的原核生物基因组为研究对象,用CodonW软件对各基因组中完全相同的功能基因的密码子使用偏好进行分析,用CD-hit软件对各基因组中以80%为阈值的重复蛋白编码基因进行分析.结果表明四个基因组的蛋白编码基因中普遍存在基因重复序列,其比例占到2.77%~7.03%.对序列完全相同的功能已知基因的分析表明其序列长度分布在50bp到1000bp左右的范围,多数长度在500bp以下;功能分析表明所研究基因组中大部分重复基因与转座酶有关,还有少量的编码转移酶、水解酶、跨膜蛋白、阻遏蛋白等.对各基因组中重复基因中序列完全相同的基因的密码子偏好性分析表明这些多拷贝基因坐落在基因组中某一特定区域并集中分布,展现出明显的共性特征.本文的尝试性工作将为今后原核基因组研究提供新思路.  相似文献   

9.
《世说新语》可称为魏晋南北朝时期载录嵇康史料的集大成的著作,其内容几乎涵盖了嵇康家世出身、生平交游、姿貌情性、著述影响等各个方面,而且从总体说具有较高的可信度,为我们从多角度、多方面认识、研究嵇康其人提供了根据或佐证。其中关于"竹林七贤"、"嵇、阮"的提法,对嵇康性格复杂性、包容性及与钟会关系的反映等值得关注。  相似文献   

10.
在中国现代文学史中,虽然旧诗退出了正统文坛,但是并没有寿终正寝。旧诗不仅作为一种文化交际工具存在于人们的日常生活中,而且,作为潜在的批评标准和审美心理严重制约着新诗的发展。尤其值得注意的是,在中小学语文教学中,不重视新诗教育,阻碍了新诗的经典化过程,使得新诗的美学特质无法融入民族审美心理。  相似文献   

11.
以世界广布的兰科植物为例.它在广东和中国的分布是非常复杂和有趣的.在中国169属当中.世界广布占2.95%.泛热带分布占4.73%.热带美洲和热带亚洲间断分布占0.6%.旧大陆热带分布6.5%.热带亚洲至热带大洋洲分布9.46%,热带亚洲至热带非洲分布2.95%.热带亚洲(印度-马来西亚)分布38.46%,北温带分布7.69%.东亚和北美间断分布2.36%.旧大陆温带分布1.18%,温带亚洲分布、地中海分布和中亚分布不存在,东亚分布14.79%.中国特有8.28%.但进一步的分析表明兰科的原始分布中心主要在东亚热带至亚热带地区.即主要是在华夏植物区系发生和发展起来的.  相似文献   

12.
新学与旧学的交相兴替,代表了晚清时期文化演变的基本走向。随着新学知识体系的形成和体制的建立,传统中学在基本内容和框架上完成了由旧学向新学的历史更替。20世纪初年国学思潮的兴起表现出学术文化的历史性转向,由以学习西方为主旨转向了以提倡国学为主要目标。这种学术文化潮流的变向,与新学发展的偏向不无关系。  相似文献   

13.
丽江大研古城是世界历史文化名城。古城的水利系统是其重要的特色之一。利用历史文献资料,结合实地考察试图讨论古城的水系分布特点,并总结其功能。  相似文献   

14.
进化是生物最本质的特征,一直以来,密码子偏好分析是基因组进化研究领域的热点命题之一.文中以极端嗜盐古菌Haloarcula hispanica基因组为研究对象,基于不同密码子偏好描述参数对该基因组大、小染色体及质粒的蛋白质编码基因中密码子使用特点进行了系统研究.结果表明Haloarcula hispanica基因组各组分蛋白质编码基因倾向使用以G/C结尾的密码子,在偏好的26个密码子中只有两个密码子的使用在大、小染色体和质粒之间存在差异.进一步基于多种描述参数的对应分析发现大、小染色体中各参数的相关系数存在相似性,而与质粒则出现了较大的差异,这可能与三者之间的进化关系有关,因而该工作为今后原核生物大小染色体与质粒之间进化关系的研究提供了可靠依据.  相似文献   

15.
In 1992 the binary divide between universities and polytechnics was dismantled to create a nominally unitary system of higher education for the UK. Just a year later, the first UK university league table was published, and the year after that saw the formation of the Russell Group of self-proclaimed ‘leading’ universities. This paper asks whether there are distinctive clusters of higher and lower status universities in the UK, and, in particular, whether the Russell Group institutions can be said to constitute a distinctive elite tier. Cluster analysis of publicly available data on the research activity, teaching quality, economic resources, academic selectivity, and socioeconomic student mix of UK universities demonstrates that the former binary divide persists with Old (pre-1992) universities characterised by higher levels of research activity, greater wealth, more academically successful and socioeconomically advantaged student intakes, but similar levels of teaching quality, compared to New (post-1992) institutions. Among the Old universities, Oxford and Cambridge emerge as an elite tier, whereas the remaining 22 Russell Group universities appear to be undifferentiated from the majority of other Old universities. A division among the New universities is also evident, with around a quarter of New universities forming a distinctive lower tier.  相似文献   

16.
比较分析了甲烷八叠球古菌(Methanosarcina mazei str.Goe1)和其他2种系统发育相关的广古细菌(嗜苦古菌(Picrophilus torridus str.DSM 9790)和盐碱古菌(Natronomonas pharaonis str.DSM 2160))的同义密码子使用偏好性.结果表明甲烷八叠球古菌的密码子使用偏好性很小,并且与GC3S值有很高的相关性.这3种广古细菌的密码子使用模式在进化上很保守.通过分层聚类分析,得出较之基因功能对密码子使用的影响,这些广古菌密码子的使用更是由其物种所决定的.考虑到这3个物种生活在pH值差异很大的环境中,推测其生活环境在很大程度上决定了这些微生物密码子的使用方式.  相似文献   

17.
通过保山市隆阳区白花蛇舌草植物群落的样地调查,发现调查区共记载维管植物28科53属59种(含亚种、变种)。植物属地理成分分析表明,白花蛇舌草生境的植物区系成分较为复杂,分布类型多样,其中泛热带分布、北温带分布、东亚分布、旧世界温带分布、热带亚洲至热带非洲分布、旧世界热带分布在群落中占有重要地位。群落成分分析表明,植物组成种类复杂,类型十分丰富。生活型谱和盖度系数分析显示,该群落以地面芽植物和高位芽植物为主,反映出其生境属于亚热带森林区域气候。白花蛇舌草适合酸性,有机质丰富,中等湿度的土壤,中、弱等的光照和亚热带温凉湿润的气候的生境条件。  相似文献   

18.
赵翼在其《廿二史札记》卷十八《新旧唐书》“新旧书互异处”条中说:“卢奂治广州,有清节。旧书谓开元以来,广府清白者,惟宋璨、裴仙先、李朝隐及奂四人。新书谓朝隐、璩及奂三人。”通过阅读史书发现,裴仙先只能称得上是清白者,而不能称清节者。两书记载不同是有其依据的,并非如赵翼所言此处仅为两书互异处。  相似文献   

19.
New World primates face problems of communication distinct from those of their Old World counterparts. We suspected that the odor of urine might serve the function of communicating information among animals or troops. Two studies were conducted withSaimiri sciureus; one examined, in a laboratory enclosure, the influence of breeding season, social condition, area, and whether the urine was from known animals or from strangers, and the second measured, in a seminatural rain forest, responses to our spreadingSaimiri urine on selected sites. Enclosure and field produce the same general patterns of frequencies of behavior for urination, the urine wash and kick wash, and rubbing. The chief difference in behavior between the environments is found in the frequency of sneezing. Season (breeding or nonbreeding) is the most effective variable producing this general pattern: During the breeding season, males urine-wash throughout the enclosure or troop range, whereas during the nonbreeding season, this behavior is restricted in location, at least in the enclosure. At this time, females increase their frequencies of sniffing and rubbing. Many of these behaviors are observed only in special locations of the enclosure. The results show thatSaimiri respond differently to the urine of known and foreign animals, depending upon the season and whether they are with members of their own sex or both sexes. It is suggested that primates not equipped with specialized organs for scent marking may use urine opportunistically to communicate.  相似文献   

20.
本文讨论了明代《世说新语》的研究情况及主要的研究形式。作者认为,明代《世说新语》的代表为王世懋和何良俊。他们的身份、地位以及他们对《世说新语》的研究观点,确立了《世说新语》三十六门类叙事的体例规范;使正文与注的相互响应与补充成为《世说新语》类拟、续之作的典范;提出了对叙述文辞与所叙内容合乎社会规范的统一的关注。对《世说新语》的传播和明清的《世说新语》拟续之作产生重大的影响。  相似文献   

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