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101.
中华姬鼠与大林姬鼠的同工酶差异 总被引:1,自引:0,他引:1
中华姬鼠(Apodemusdraco)和大林姬鼠(Apodemuspeninsulae)是形态学上十分相似的两种鼠类。为了对两种姬鼠的分类提供生物化学方面的依据,采用聚丙烯酰胺凝胶等电聚焦电泳方法比较和分析了两种姬鼠的LDH同工酶、EST同工酶和SOD同工酶的差异。结果表明,两种姬鼠的LDH同工酶酶谱基本相似,而EST同工酶和SOD同工酶酶谱则存在明显的种间差异。根据EST同工酶A2带的有无和SOD同工酶主带等电点的差别,能将两种姬鼠很容易区分开来。 相似文献
102.
MURAT EKICI ZEKI AYTAÇ HASAN AKAN MÜNEVVER PINAR 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(4):741-747
A new species of Astragalus L., A. trabzonicus (section Onobrychoidei DC.), is described and illustrated from north‐east Anatolia in Turkey. The diagnostic, pollen morphological, and chromosomal characteristics are discussed. A distribution map and conservation status are given. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 741–747. 相似文献
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MARCELO DA COSTA SOUZA MARLI PIRES MORIM 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(2):306-308
A new species, Eugenia marambaiensis M.C.Souza & M.P.Morim, is described and illustrated. It is characterized by having large translucent gland dots densely distributed on the leaves, with a caudate apex and slightly wavy margins and a glabrous raceme, with only two flowers. Eugenia marambaiensis was only found in the locality of Restinga da Marambaia, Rio de Janeiro, Brazil. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 306–308. 相似文献
105.
Luiz F. C. Tencatt Janice Muriel-Cunha Jansen Zuanon Marlon F. C. Ferreira Marcelo R. Britto 《Journal of fish biology》2020,97(4):1072-1086
Aspidoras azaghal n. sp. was discovered during a multitaxonomic scientific expedition to the remote Amazon Terra do Meio region in tributaries to the rio Xingu basin, Pará, Brazil. The new species can be promptly distinguished from its congeners by the following combination of features: (a) absence of the first dorsal-fin element; (b) parieto-supraoccipital fontanel located medially on bone; (c) absence of a longitudinal dark-brown or black stripe along flank midline; (d) ventral surface of trunk covered by clearly smaller, irregular and/or roundish platelets; (e) inner laminar expansion of infraorbital 1 well developed; (f) relatively wide frontal bone, with width equal to half of entire length; (g) absence of a thick, longitudinal conspicuous dark-brown stripe along dorsal portion of flank; and (h) poorly developed serrations on posterior margin of the pectoral-fin spine. Besides morphological evidence, the molecular analyses indicated significant differences between the new species and its congeners, with A. albater and A. raimundi as its closest species, showing 6.53% of genetic differentiation in both cases. The intraspecific molecular data revealed gene flow (peer fixation index, FST = 0.05249, P > 0.05, for the cytochrome oxidase I (COI) marker and FST = -0.01466, P > 0.05, for the control region) between specimens upstream and downstream from a 30-m height waterfall at the type-locality, which therefore represent a single population. Furthermore, it was possible to observe a unidirectional gene flow pattern, with genetic diversity increasing in the downstream direction. 相似文献
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108.
I. A. Bryantseva V. M. Gorlenko T. P. Tourova B. B. Kuznetsov A. M. Lysenko S. A. Bykova V. F. Gal’chenko L. L. Mityushina G. A. Osipov 《Microbiology》2000,69(3):325-334
Two new species of heliobacteria isolated from cyanobacterial mats of two alkaline sulfidic hot springs are formally described.
Strains BR4 and BG29 are assigned to anoxygenic phototrophic bacteria of the familyHeliobacteriaceae, since they possess the unique properties of this taxon: strict anaerobiosis, formation of bacteriochlorophyllg, the lack of extensive intracytoplasmic membranes and chlorosomes, an unusual cell wall structure, and phylogenetic relatedness
to the low G+C gram-positive eubacteria. Based on the 16S rDNA sequence similarity, strains BR4 and BG29 are assigned to the
genusHeliobacterium and described as two new species of this genus:Heliobacterium sulfidophilum sp. nov. andHeliobacterium undosum sp. nov. The G+C content of the DNA is 51.3 mol % inHbt. sulfidophilum and 57.2-57.7 mol % inHbt. undosum. The cells ofHbt. sulfidophilum are rods, and the cells ofHbt. undosum are slightly twisted spirilla or short rods. Both new bacteria are motile by peritrichous flagella.Hbt. sulfidophilum produces endospores. The new bacteria are strict anaerobes growing photoheterotrophically on a limited range of organic compounds.
In the dark, they can switch from photosynthesis to the slow fermentation of pyruvate. Biotin is required as a growth factor.
Both species are highly tolerant to sulfide (up to 2 mM at pH 7.5) and oxidize it photoheterotrophically to elemental sulfur;
photoautotrophic growth was not observed. The temperature optimal for growth ofHbt. sulfidophilum andHbt undosum is 30–35‡C, and the optimal pH is 7–8. 相似文献
109.
Maria A. Faust 《Journal of phycology》1993,29(1):100-107
Three new benthic dinoflagellate species, Prorocentrum belizeanum, Prorocentrum elegans, and Prorocentrum caribbaeum, from mangrove floating detritus are described from scanning electron micrographs. Species were identified based on shape, size, surface micromorphology, ornamentation of thecal plates, and architecture of the periflagellar area and intercalary band. Cells of P. belizeanum are round to slightly oval with a cell size of 55–60 μm long and 50–55 μm wide. Areolae are round and numerous (853–1024 per valve) and range from 0.66 to 0.83 μm in size. The periflagellar area of P. belizeanum is a broad V-shaped depression; it accommodates a flagellar and an auxiliary pore and a flared, curved apical collar. The intercalary band of P. belizeanum is horizontally striated. Prorocentrum elegans is a small species 15–20 μm long and 10–14 μm wide, with an ovate cell shape. The thecal surface is smooth. Two sizes of valve pores were recognized: large, round pores (20–22 per valve) arranged in a distinct pattern and smaller pores situated in an array along the intercalary band. The periflagellar area is V-shaped; it accommodates an uneven sized flagellar pore, an auxiliary pore, and an angled protuberant flagellar plate. The intercalary band is transversely striated. It is a bloom-forming species. Prorocentrum caribbaeum cells are heart-shaped with a rounded anterior end and a pointed posterior end. Cells range from 40 to 45 μm long and 30 to 35 μm wide. Thecal surface has two different-sized pores: large, round pores (145–203 per valve) arranged perpendicularly from the posterior margins, and small, round pores unevenly distributed on the thecal surface. The periflagellar area is ornate. It is V-shaped with a curved apical collar located next to the auxiliary pore; a smaller protuberant apical plate is adjacent to the flagellar pore. The intercalary band is transversely striated and sinuous. Cells are active swimmers. 相似文献
110.
J. FRANCISCO-ORTEGA F.L.S. M. T. JACKSON A. SANTOS-GUERRA B. V. FORD-LLOYD 《Botanical journal of the Linnean Society. Linnean Society of London》1993,112(2):187-202
FRANCISCO-ORTEGA, J., JACKSON, M. T., SANTOS-GUERRA, A. & FORD-LLOYD, B. V., 1993. Morphological variation in the Chamaecytisus proliferus (L.f.) Link complex (Fabaceae: Genisteae) in the Canary Islands . A multivariate study (Principal Component Analysis and Cluster Analysis, Warďs method) of 47 morphological traits from 164 populations of Chamaecytisus proliferus (L.f.) Link from the Canary Islands confirmed that this species complex is formed by seven morphological types. At least eight traits discriminated between these types. Patterns of variation follow a cline within Gran Canaria, Tenerife and La Palma. These results also show that morphological variation is greater in the eastern islands (i.e. Gran Canaria and Tenerife) than in the western islands (La Gomera, El Hierro and La Palma) and that no morphological differences are found between plants of typical tagasaste from wild and cultivated populations. 相似文献