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41.
42.
In their monograph of the dileptids, Vďačný and Foissner (2012) could not clarify the type species of the genus Dileptus Dujardin, 1841. Thus, they suggested that the problem be referred to the International Commission on Zoological Nomenclature. However, recently we discovered that Dujardin (1841) has originally typified Dileptus with Amphileptus anser sensu Ehrenberg (1838) which is in fact a misidentified Amphileptus margaritifer Ehrenberg, 1833, a common species also originally classified in Dileptus. Under Article 70.3.2 of the Code, Dileptus margaritifer (Ehrenberg, 1833) Dujardin, 1841, thoroughly redescribed by Foissner et al. (1995), is now the type of Dileptus. This has the great advantages of historical continuity and that new combinations (names) are not required.  相似文献   
43.
Paraholosticha muscicola, type species of Paraholosticha Wenzel, inhabits mainly terrestrial habitats, but also freshwater. A brackish water population from Korea is described, the first record from such a habitat. Principal component analysis shows that this population is more similar to a terrestrial population from Denmark than to a population from Antarctic soil. Keronopsids have two strong morphological/ontogenetic apomorphies (frontal corona formed from anlagen I–III; division in cysts). However, the SSU rRNA sequence of the Korean population does not cluster with that of the Antarctic population in the phylogenetic tree, but both branch off consecutively and immediately before a mixture of other non-dorsomarginalian hypotrichs, including two further keronopsids. Furthermore, the keronopsids cluster in the phylogenetic network, providing phylogenetic conflicts, which cannot be exemplified in the conventional gene tree. To complete the picture of P. muscicola, we provide a detailed overview about nomenclature, history, taxonomy, and its geographic distribution. From the four synonyms proposed so far, we tentatively accept only P. lichenicola and P. ovata. Paraholosticha algivora is likewise very similar. Thus we propose to include these three taxa as members of the P. muscicola complex. Stylonethes sterkii and P. algivora are transferred to Paraholosticha Wenzel. A key to the Paraholosticha species is provided.  相似文献   
44.
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D E Pittaway 《Steroids》1978,32(2):157-163
The substrate specificity of 17beta-hydroxysteroid oxidoreductase (17beta-HOR) activity was investigated in microsomal preparations of canine testes. Enzyme activity was measured by quantitating the conversion of radioactive substrates to products. The apparent Michaelis constants were determined to be 1.3 x 10(-6)M for androstenendione, 3--10 x 10(-6)M for dehydroepiandrosterone and 25 x 10(-6)M for estrone. These data are similar to those reported for human testicular 17beta-HOR activity and suggest that the canine activity may serve as an animal model for the study of testicular 17beta-HOR.  相似文献   
46.
Abstract. This is the 3rd edition of the Code of phytosociological nomenclature, prepared by the Nomenclature Commission of the International Association for Vegetation Science (IAVS) and the Fédération Internationale de Phytosociologie (FIP) on the basis of the 2nd edition. The Code consists of a series of definitions, principles, rules and recommendations which will facilitate the proper use of syntaxonomical names for the denomination of syntaxonomical units.  相似文献   
47.
We find that Brachirus Swainson, 1839 is a valid soleid (Pleuronectiformes) genus name, Euryglossa Kaup, 1858 is an invalid soleid genus name, and Synaptura Cantor, 1849 is a junior objective synonym of Brachirus. However, for the sake of taxonomic stability and because Synaptura Cantor, 1849 has had a long-term consistent usage within the Soleidae for four species (S. commersoni, S. lusitanica, S. marginata, and S. albomaculata) forming a monophyletic group, we will petition the International Commission on Zoological Nomenclature to recognize Synaptura Cantor, 1849 as a valid genus name with its type-species being Pleuronectes commersoni Lacepède, 1802. Received: September 19, 1999 / Revised: November 2, 2000 / Accepted: February 20, 2001  相似文献   
48.
Abstract. Soil samples were collected before and after an experimental fire on a heathland in the province of León (Spain). The seed banks were assessed by counting the numbers of seedlings appearing of Erica australis and Calluna vulgaris. A total of 2285 germinable seeds/m2 before burning and 1177 germinable seeds/m2 after the fire were estimated for Erica australis, and 90 and 690 germinable seeds/m2, respectively, for Calluna vulgaris. After the fire the number of germinable seeds/m2 of Erica australis had decreased, whilst there was a considerable increase in the number of germinable seeds/m2 of Calluna vulgaris. Neither seedlings nor sprouts of Calluna vulgaris had appeared in the field plots 10 months after the fire. Erica australis did recover mainly by sprouting after fire.  相似文献   
49.
About 50% of acute myeloid leukemia (AML) patients show the occurrence of non-random chromosome rearrangements. Most of the recurrent karyotypic rearrangements in AML have been defined as distinct disease entities in the 2008 World Health Organization (WHO) classification. In this paper we report an AML case showing a novel t(4;16)(q25;q23.1) rearrangement causing the activation of epidermal growth factor (EGF) and elongation of long-chain fatty acids family member 6 (ELOVL6) genes, rather than the generation of a novel fusion gene.  相似文献   
50.
讨论《国际动物命名法规》(简称《法规》)关于种级单元异物同名的处理及相关规定。以斧须隐翅虫亚科Oxyporinae的同名问题为例,笔者分析了属级单元名称变动对种级单元同名关系的影响。一些古老的属级单元有很长且比较复杂的分类历史,深入分析可将各类变化归纳为六类,其中三类与原同名有关,二类与后同名有关,余一类不再影响种级同名关系。文中讨论了第4版《法规》中与种级同名关系有关的若干重要变动,通过分析比较,说明《法规》的这类变动如何影响动物分类名称的稳定性与正确性。这些分析,可望有助于避免产生新的次同名,也有助于正确恰当地解决已有的同名问题。  相似文献   
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