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61.
Three Gabrius species, Gabrius mandschuricus Bernhauer, G. praesignis Schillhammer and G. zerchei Schillhammer, are identified for the first time in Korea. A taxonomic key of Korean Gabrius species is provided.  相似文献   
62.
The global distribution, abundance, and diversity of microscopic freshwater algae demonstrate an ability to overcome significant barriers such as dry land and oceans by exploiting a range of biotic and abiotic colonization vectors. If these vectors are considered unlimited and colonization occurs in proportion to population size, then globally ubiquitous distributions are predicted to arise. This model contrasts with observations that many freshwater microalgal taxa possess true biogeographies. Here, using a concatenated multigene data set, we study the phylogeography of the freshwater heterokont alga Synura petersenii sensu lato. Our results suggest that this Synura morphotaxon contains both cosmopolitan and regionally endemic cryptic species, co‐occurring in some cases, and masked by a common ultrastructural morphology. Phylogenies based on both proteins (seven protein‐coding plastid and mitochondrial genes) and DNA (nine genes including ITS and 18S rDNA) reveal pronounced biogeographic delineations within phylotypes of this cryptic species complex while retaining one clade that is globally distributed. Relaxed molecular clock calculations, constrained by fossil records, suggest that the genus Synura is considerably older than currently proposed. The availability of tectonically relevant geological time (107–108 years) has enabled the development of the observed, complex biogeographic patterns. Our comprehensive analysis of freshwater algal biogeography suggests that neither ubiquity nor endemism wholly explains global patterns of microbial eukaryote distribution and that processes of dispersal remain poorly understood.  相似文献   
63.
64.
The effect of appearance characteristics of fresh pork on Korean consumers' preferences was assessed using images of pork chops. Consumers (1015) in six provinces selected their preferred chop from 16 images modified systematically to give two levels each of fat cover, color, marbling and drip. Meat color was the most important characteristic; similar numbers of consumers chose the dark and light red meat colored pork. Almost two‐thirds of the consumers chose consistently the option without drip. A strong characteristic was that almost half of the Korean consumers chose the marbled pork, although fat cover was not an important selection criterion. Similar preferences were observed on a regional basis, except for color, which varied according to region. More female, particularly the married ones, than male consumers preferred the light red, no drip and marbled options.  相似文献   
65.
Lee SY  Park H  Boo KS  Park KT  Cho S 《Molecules and cells》2005,19(3):391-397
Molecular identification techniques are used where morphological characters are not useful for distinguishing species that resemble each other closely. The example studied here is the Adoxophyes species complex, in which A. orana (Fischer von R?sslerstamm) is officially the only known Korean species in the genus Adoxophyes (Lepidoptera: Tortricidae). However there have been suspicions that at least two types of A. orana exist in Korea based on the distribution and range of the host, with A. orana attacking apples and peaches, and another Adoxophyes sp. attacking tea and pears. The latter is presumed to be A. honmai (Yasuda), but the two have remained confused because of their extreme morphological similarity, despite several Asian studies of pheromonal and morphological characteristics. To confirm the occurrence of an Adoxophyes species other than A. orana in Korea, we compared 940 bp of the mitochondrial cytochrome oxidase I (COI) gene from 16 samples of Adoxophyes and found that there is a second Adoxophyes species different from A. orana. Comparison of the different sequences to that of Japanese A. honmai confirmed that they belong to the latter. From the sequence difference between the two Korean species, we were able to develop new PCR primer sets that distinguish them. This molecular identification technique with no enzyme digestion or sequencing step is a convenient and rapid way of differentiating between species that are hard to distinguish morphologically.  相似文献   
66.
猪屎豆灯蛾(Utethesia pulchela Linne)又称褐斑灯蛾、红黑斑灯蛾等,属鳞翅目,灯蛾科,是一种鲜艳美丽的中型蛾子。为害大叶猪屎豆、小叶猪屎豆、太阳麻、大眼蓝、木豆、甘蔗等作物,尤以大叶猪屎豆受害最烈,除了为害叶及花外,还会钻入果荚中吃种子。据1957年11月间在同安县后田村检查的结果,大叶猪屎豆受害果荚严重的达66%,  相似文献   
67.
Abstract The present paper is a part of the studies on the larvae of subfamily Galerucinae in Korea and Japan. Five species belonging to the Non-glanduliferous group in the subfamily Galerucinae were described and illustrated: Lochmaea capreae (Linnaeus), Atrachya menetriesi (Fladermann), Aulacophora indica (Gmelin), Exosoma flaviventre (Motschulsky), Fleutiauxia armata (Baly). A key and taxonomic remarks are also given.  相似文献   
68.
蛋白质芯片SELDI-TOFMS技术的研究进展及其在临床中的应用   总被引:8,自引:0,他引:8  
蛋白质芯片为新一代的蛋白质组研究技术,由美国Ciphergen生物系统公司引进,表面增强激光解吸电离-飞行时间质谱(SELDI-TOFMS)提供一个高通量和高灵敏度的检测平台。投放至今虽短短10来年,但卓越的成果已广为医学科学界重视,尤其在恶性肿瘤的早期诊断、监控和预后研究上。蛋白质是细胞内执行生物功能的最终分子,蛋白质组学研究让人类更深入了解疾病和生命的本源,不断发现的特异性肿瘤标志物更为攻克癌症带来新希望。这里除对表面增强激光解吸电离_飞行时间质谱作较详尽的介绍外,更重点阐述其近年来蛋白质芯片近期的研究进展和在临床中的应用,并就其优劣和发展前景作出评估。  相似文献   
69.
蛋白质芯片为新一代的蛋白质组研究技术,由美国Ciphergen生物系统公司引进,表面增强激光解吸电离-飞行时间质谱(SELDI-TOFMS)提供一个高通量和高灵敏度的检测平台。投放至今虽短短10来年,但卓越的成果已广为医学科学界重视,尤其在恶性肿瘤的早期诊断、监控和预后研究上。蛋白质是细胞内执行生物功能的最终分子,蛋白质组学研究让人类更深入了解疾病和生命的本源,不断发现的特异性肿瘤标志物更为攻克癌症带来新希望。这里除对表面增强激光解吸电离-飞行时间质谱作较详尽的介绍外,更重点阐述其近年来蛋白质芯片近期的研究进展和在临床中的应用,并就其优劣和发展前景作出评估。  相似文献   
70.
大豆异黄酮的分离与纯化   总被引:1,自引:0,他引:1  
天然大豆异黄酮作为健康食品在防治骨质疏松和癌症方面具有一定功效。由于化合物结构相似,异黄酮甙元特别是高纯度黄豆黄素(glycitein)的获得有一定难度,文献报道大多是通过盐酸水解异黄酮甙的方法获得,而这种方法对环境污染和工厂生产设备腐蚀较大。本文报道了用醇溶剂进行固相提取以及硅胶柱色谱方对含有三种大豆异黄酮甙元的混合物产品进行分离。通过低成本和无环境污染的固相提取方法得到纯度为97%的黄豆黄素和纯度超过95%的大豆黄素(daidzein);95%纯度的另一种大豆甙元金雀异黄素(genistein)则通过硅胶柱色谱分离得到。应用硅胶柱色谱,一次性分离了一种含有两个异黄酮甙:大豆甙(daidzin)和黄豆甙(glycitin)的产品。  相似文献   
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