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陈报章 《徐州师范大学学报(自然科学版)》1992,(1)
地方性氟中毒是一种在全球流行的地方病。本文介绍了其概念、研究史和研究现状,探讨了地氟病的病理学特征及病区的成因,并初步分析了地氟病在人群中的分布规律及在我国的地理流行特征。 相似文献
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Identification and classification of subspecies of Asian cultivated rice and their hybrids 总被引:2,自引:0,他引:2
Xiangkun Wang Renhua Li Chuanqing Sun Zichao Li Hongwei Cai Xinli Sun 《科学通报(英文版)》1998,43(22):1864-1864
Having reviewed the major classification systems proposed by various scholars across the world, it is found thatindica andjaponica underO. sativa L. are two major directions thoroughly differentiated from the Asian cultivated rice, forming the framework of the classification
structure. A system withindica andjaponica as the only two subspecies is therefore reiterated. There are various ways to determine the indica-japonica identity of hybrid
rice, but the “combined morphological trait index” (CMT index) method is more efficient and easier to handle, although the
isozyme analysis, molecular marker analysis and grain quality assay methods are also feasible. 相似文献
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Since the introduction of an African subspecies into Brazil in the mid-1950's1, descendent Africanized honey bees (Apis mellifera L.) have spread throughout the Neotropics and into temperate North America. Restriction enzyme analysis of 422 feral honey bee colonies collected from non-Africanized areas in the southern United States revealed that over 21% of them had mitochondrial DNA (mtDNA) derived from a European race established in North America by the 17th century, 77% of them had mtDNA common in honey bees maintained by beekeepers and about 1% exhibited African mtDNA. Further analysis revealed that the African mtDNA was derived from a north African subspecies imported to the US in the 19th century. 相似文献
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《Journal of Natural History》2012,46(6):923-949
Summary The current status of Australian diplurine genera is presented. The following genera are recognized here: Aname Koch, Chenistonia Hogg, Ixamatus Simon, Kiama Main and Mascord, Stanwellia Rainbow and Pulleine, Teyl Main, Troglodiplura Main and Xamiatus Raven. Aparua Todd from New Zealand is newly synonymized with Stanwellia Rainbow and Puleine. Two new genera, Kwonkan and Merredinia and six new species are described: Kwonkan anatolion, eboracum, goongarriensis, moriartii and silvestre and Merredinia damsonoides. Dekana wonganensis Main is designated as the type species of Kwonkan. The tribe Anamini Simon is rediagnosed and Anamini Raven newly synonymized with it. Aname, Chenistonia and the two new genera are attributed to the Anamini. 相似文献
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《Journal of Natural History》2012,46(13-16):925-936
Morphological and genetic data for the Iberian golden‐striped salamander, Chioglossa lusitanica, demonstrate the existence of two groups with southern and northern ranges, connected by a zone of intergradation in central Portugal. Because reproductive isolation between them is incomplete we consider the groups to be subspecies. The type locality of C. lusitanica (Buçaco near Lousã) is situated inside the mixed zone. This necessitates identification of the nominotypical subspecies. We sequenced a fragment of mitochondrial DNA from one of the species' syntypes and we determined what position over a latitudinal transect maximizes the morphological discrimination between the groups. Both approaches indicate that C. lusitanica from Buçaco represents the southern subspecies. A new subspecies of C. lusitanica is described from a northern locality (Valongo near Porto in north‐western Portugal). A lectotype is designated for Chioglossa lusitanica. 相似文献
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白色六索线虫一新亚种——中华亚种Hexamermis albicans sinensis ssp.nov. 总被引:4,自引:0,他引:4
本文记述了分布于我国安徽麦套棉田以及湖北、河南麦田中,寄生于小地老虎、粘虫幼虫体内的一种六索线虫,这种线虫与世界广布种白色六索线虫的基本特征相似,但又存在着某些地理上的差异,故将之定命为白色六索线虫中华亚种。 相似文献
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黑琴鸡(Lyrurus tetrix)生物学研究进展(Ⅰ)——地理分布、亚种分化、食性、生境选择及其行为 总被引:2,自引:0,他引:2
对黑琴鸡地理分布和亚种分化、食性、生境选择及行为研究的新进展进行了综述 相似文献
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秦岭植物区系的特有现象研究 总被引:1,自引:0,他引:1
傅志军 《信阳师范学院学报(自然科学版)》1999,12(2):242-245
秦岭有中国种子植物特有属47属,含61种,现代地理分布呈现出西南-华中-华东分布型最多,华中-华东分布型和西南-华北分布型次之,华北分布型和横断山-藏南分布型最少。分布于秦岭的中国特有属植物主要处于中海拔地带,且西段和南坡较东段和北坡我,显示出温带性质。 相似文献
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小菊头蝠、单角菊头蝠和角菊头蝠在形态上甚相似,关于小菊头蝠和单角菊头蝠的分类地位问题存有不同观点.通过分析细胞色素b基因全序列探讨了小菊头蝠和单角菊头蝠的分类地位.应用MEGGA 2软件计算出小菊头蝠与单角菊头蝠之间的未修正序列分歧仅为1.2%~1.4%,二者与角菊头蝠之间的未修正序列分歧分别为2.5%~3.0%和2.1%~2.5%,未达到种间分歧值,因此认为小菊头蝠、单角菊头蝠和角菊头蝠应为同一种,并支持Ellerman(1951)和Koopman(1993)的观点:小菊头蝠和单角菊头蝠是角菊头蝠的两个亚种.同时计算出小菊头蝠和单角菊头蝠最早从角菊头蝠中分化出来的时间大约在136.7万年前. 相似文献