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山茶属茶组植物的订正   总被引:55,自引:5,他引:50  
  相似文献   
2.
茶皂素生产工艺及其应用的研究进展   总被引:7,自引:0,他引:7  
本文综述了天然非离子表面活性剂茶皂素的生产工艺以及在实际中的应用 ,并就目前的生产和使用情况提出了一些看法和需要解决的问题。  相似文献   
3.
Two influential articles published in the 1970s suggested that pressure from Christian fundamentalists, subsequent to the Scopes trial of 1925, forced American high school biology textbook authors and publishers to significantly limit discussion of the topic of evolution. The conclusions reached by these studies have become foundational for historians examining the interplay between science and religion in the United States in the twentieth century. However, a reexamination of key twentieth century biology textbooks suggests that the narrative that the treatment of the theory of evolution was held hostage to anti-rational cultural forces is largely a myth, created first as part of a public relations effort by the Biological Sciences Curriculum Study (BSCS) to differentiate, defend, and promote its work, and later as part of an attempt by scholars to sound a warning concerning the rise of the religious right. A focus on this narrative has not only allowed biologists to sidestep uncomfortable questions regarding the race-biased and class-biased assumptions embedded within the concept of evolutionary progress, it has also limited reliance on the texts in question as reliable reflections of the cultural assumptions of educators and scientists. A reexamination of the most popular American biology textbooks from 1907 to 1963, particularly the work of Ella Thea Smith, provides evidence in support of these contentions.  相似文献   
4.
贵州大树茶的核型变异与进化   总被引:12,自引:0,他引:12  
本文对贵州大树茶7种1变种11类型的核型进行了分析。结果表明,这些种类均为二倍体2n=30。五室茶Camellia quinquelocularis 2n=30=24m+6sm;四球茶C.tetracocca 2n=30=22m+8sm;大理茶C.taliensis 2n=30=22m+8sm;秃房茶C.gymnogyna 2n=30=22m+6sm+2st与2n=30=20m+8sm+2st;假秃房茶C. gymnogynoides 2n=30=22m+6sm+2st与2n=30=20m+8sm+2st;榕江茶C. jungkiangensis 2n=30+20m+8sm+2st;茶C.sinensis 2n=30=20m+8sm+2st以及变种淡红花茶C.sinensis var.ruolla 2n=30=20m+8sm+2st;均属2A核型。染色体结构变异在茶组植物演化中起了重要作用。所划分的两大类核型,即m和sm类与m,sm,和st类是与其子房室数,即5室和3室相一致的。根据核型的不对称性程度、外部形态及生化分析,探讨了各种类的亲缘关系与系统演化途径,论证了茶组植物的原产地是位于滇、桂、黔毗邻交汇处的云贵高原,探讨了茶组植物的分类学问题。  相似文献   
5.
Bymeans of HPLC technique, the theanine and gallic acid in the leaves of six species and three varieties of Camellia sect. Thea were analyzed. The results showed that both of them were generally occured in these plants and the contents in C. taliensis and C. kwangsiensis are mostly close to those of C. sinensis var. assamica. Since the leaves of C. taliensis have also been historically used for preparing tea by folk peoples of Yunnan province, it could be suggest that C. taliensis might one of the original plants of tea  相似文献   
6.
Monofluorocarbon acids can be formed from inorganic fluoride by single cell cultures of Acacia georginae and tea. Fluorocitrate is also present in small amounts in commercial specimens of tea and oatmeal. The significance of these observations is discussed, especially in relation to the toxic plants.  相似文献   
7.
栽培茶树的驯化起源与传播   总被引:2,自引:0,他引:2  
茶作为世界上最重要的饮品之一, 其栽培类型的驯化起源一直是人们关注的热点。本文总结了近年相关研究的进展, 讨论了存在的问题, 并对未来的研究方向提出建议。长江流域及以南地区分布有众多栽培茶树的野生近缘种, 特别集中于云南、贵州、广西等地; 一方面南方各族语言中“茶”发音的相似, 暗示了茶知识起源的单一性, 最可能起源于古代的巴蜀或云南, 另一方面遗传分析揭示栽培的茶存在多个起源中心, 即使Camellia sinensis (L.) O. Kuntze的几个栽培变种也可能起源于不同的地区; 文献记载, 茶的栽培中心曾经从西向东再向南迁移, 遗传多样性的变化也揭示了这一可能性, 但考古发现却提示最早的栽培茶可能出现在长江流域的最东部。我们推测在茶知识及栽培品种的传播过程中, 各地野生近缘植物的基因渗入栽培类型中, 或各地居民直接用当地野生茶培育出新的栽培茶类型, 从而导致遗传上的复杂性和语言上的一致性并存。茶树的祖先类型、起源地点、起源时间以及栽培品种的演变历程都还需要更为明确的证据, 未来应该以整个茶组植物为对象, 将茶文化、群体遗传学、谱系地理、人类学、气候变化、考古等多学科研究进行整合分析。  相似文献   
8.
Karyotypes of seven species, one variety and 11 forms of Sect. Thea occurring in Guizhou Province, were investigated by the wall degradation hypotonic method. The micrographs of their somatic metaphase are shown in plates 1-2 and the parameters of chromosomes according to Li and Chen (1985) are given in Table 1 and the idiograms in Fig. 1. The karyotype formulae are as follows: Camellia quinquelocularis 22=30=24m+6sm; C. tetracocca 2n=30=22m+8sm; C. taliensis 2n=30=22m+8sm; C. gymnogyna 2n=30=22m +6sm+2st and 2n=30=20m=8sm+2st; C. gymnogynoides 2n=30=22m +6sm+2st and 2n=30=20m+8sm+2st; C. jungkiangensis 2n=30=20m+8sm+2st; C. sinensis 2n =30+20m+8sm+2st, and C. sinensis var. ruoella 2n=30=20m+8sm+2st. All the karyotypes belong to Stebbins “2A”. The following main aspects are discussed. 1. Chromosome numbers: All these species are found to have 2n=30. Based on the previous and present reports, It clearly indicates that evolution of this group has taken place mainly on diploid level, but not on polyploid one. 2. The karyotype variation: Generally, all the karyotypes examined are similar, but according to symmetry of karyotype, they may be grouped into two types. One is characterized by metacentric (m)and submetacentric (sm)chromosomes, involving C. quinquelochlaris, C. tetracocca, C. taliensis, while the other is characterized by a pair of subtelocentric (st) chromosome besides m and sm chromosomes, involving C. gymnogyna, C. gymnogynoides, C. jungkiangensis, C. sinensis and C. sinensis var. ruoella. It is suggested that the mechanism for karyotype variation and speciation in Sect. Thea be pericentric inversion or reciprocal translocation. The first type is more symmetrical than the second one, and is thus relatively primitive. 3. The orginal center of Sect. Thea: Based on the analysis of karyotypes, morphological characters, geographical distribution and biochemical features, the authors consider that the Yunnan-Guizhou plateau including the contiguous area in Yunnan, Guangxi and Guizhou is the original center, from where it radiated, resulting in the present distribution pattern of Sect. Thea.4. Taxonomic treatment of Sect. Thea: The taxonomic treatment of Sect. Thea is complicated and still confused up to now. The number of species is more than 40 according to Zhang’s taxonomic system (1984), but, recently, most of them are reduced by Min (1992). Further work should be based on the concept of morphological discontinuity and in formation from other branches of sciences. Whether two types of karyotype are two biological species remains questionable.  相似文献   
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