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11.
《Journal of Natural History》2012,46(9):1259-1290
Monocotyle is revised and three new species are proposed. Monocotyle corali sp. nov. is described from the gills of the cowtail ray, Pastinachus sephen (Forsskål) (Dasyatididae), and is distinguished from other members of Monocotyle by the large hamuli with a distinct tail on the guard and by the male copulatory organ with three loops and a wing-like accessory piece at the distal end. Monocotyle jordani sp. nov. from the gills of the southern eagle ray, Myliobatis australis Macleay (Myliobatididae), is differentiated by the male copulatory organ with a large, unique accessory piece. Monocotyle youngi sp. nov., from the gills of Himantura fai Jordan and Seale (Dasyatididae), has marginal haptoral papillae armed with 12 to 15 sclerites, a male copulatory organ with 20 loops and a unique accessory piece at the distal end. Monocotyle trygoni (Venkatanarsaiah and Kulkarni, 1980) Timofeeva, 1985 is synonymized with M. spirophallus Tripathi, 1959 and M. spirophallus is redescribed fully. There are now 16 valid species of Monocotyle and a key to species is presented. Additional data and illustrations of important taxonomic characters are provided. The developmental sequence of the male copulatory organ of M. spiremae Measures, Beverley-Burton and Williams, 1990 from juvenile to adult is described. The anterior glands and the type of secretion they contain are also documented for several species of Monocotyle.  相似文献   
12.
《Journal of Natural History》2012,46(16):2119-2131
Recent surveys of the plethodontid salamander fauna of Oaxaca, Mexico, disclosed the existence of a new, morphologically distinct arboreal species of the genus Pseudoeurycea. The new species, described here, is from the Sierra Mazateca in northern Oaxaca. Sequences of 1833 base pairs of the 16S, cytochrome b and ND4 mitochondrial DNA (mtDNA) genes from the new taxon were used to assess its phylogenetic position. Previous phylogenetic analyses based on mtDNA supported recognition of four clades within Pseudoeurycea: P. bellii, P. gadovii, P. juarezi and P. leprosa-Lineatriton species groups. One additional species, P. unguidentis, was not closely allied to any of the four groups. Re-analysis including the additional sequences reported here establishes a sister-group relationship between the new species and P. unguidentis. Moreover, it supports this clade as part of the P. juarezi species group.  相似文献   
13.
《Journal of Natural History》2012,46(20):2655-2668
Examination of fossil and Recent specimens from the Sicilian area belonging to the Phylactella labrosa ‘complex’ revealed two new species: P. mediterranea sp. nov., a Pleistocene-to-Recent taxon and P. megarensis sp. nov., from Pleistocene sediments from eastern Sicily. Ecological, geographical and stratigraphical distribution of both new species are discussed also in comparison with P. labrosa.  相似文献   
14.
《Journal of Natural History》2012,46(8):1045-1057
Three new species are described from the relatively well-known deep Mediterranean protobranch fauna. Yoldiella wareni n. sp. is a miniaturized species so far misidentified as Yoldiella micrometrica (Seguenza, 1877), which is a Pleistocene species (neotype here designated). Yoldiella ovulum n. sp. is similar to Y. micrometrica, of which it may represent a descendant species. Ledella marisnostri n. sp. is the second species known for the genus in the Mediterranean. These three species are thought to be endemic to the Mediterranean, where they may represent either persisting Plio-Pleistocene species which survived the changes from psychrospheric to homeothermic conditions, or newly adapted species, evolved from Plio-Pleistocene ancestors. In the second case, they seem to be the result of an ongoing differentiation of the deep Mediterranean protobranch fauna from the North-East Atlantic one, due to the physical isolation of the Mediterranean basin.  相似文献   
15.
《Journal of Natural History》2012,46(25-26):1573-1613
Proserpinicaris young sp. nov., Proserpinicaris wangpi sp. nov. and Proserpinicaris imjin sp. nov. are described from subterranean waters of South Korea. They are short-range endemics, allopatric in distribution and closely related to each other, and to two other Far Eastern congeners. Distinguishing features are limited to the general habitus shape, proportions of the caudal rami and degree of sexual dimorphism. The genus Proserpinicaris Jakobi, 1972 Jakobi, H. 1972. Trends (Enp.P4 Mänchen) innerhalb der Parastenocarididen (Copepoda Harpacticoidea). Crustaceana, 22: 127146. [Crossref] [Google Scholar], as redefined here, is Palaearctic in distribution, with the centre of diversity in southern Europe, and 20 valid members, all of which share a large hyaline spiniform structure on the male fourth leg basis as a synapomorphy. A key to species is provided. Genera Niponnicaris Jakobi, 1972 Jakobi, H. 1972. Trends (Enp.P4 Mänchen) innerhalb der Parastenocarididen (Copepoda Harpacticoidea). Crustaceana, 22: 127146. [Crossref] [Google Scholar] and Pannonicaris Jakobi, 1972 Jakobi, H. 1972. Trends (Enp.P4 Mänchen) innerhalb der Parastenocarididen (Copepoda Harpacticoidea). Crustaceana, 22: 127146. [Crossref] [Google Scholar] are established as its junior subjective synonyms, Lacustricaris Jakobi, 1972 Jakobi, H. 1972. Trends (Enp.P4 Mänchen) innerhalb der Parastenocarididen (Copepoda Harpacticoidea). Crustaceana, 22: 127146. [Crossref] [Google Scholar] is formally synonymized with Parastenocaris Kessler, 1913, and Parastenocaris lacustris Chappuis, 1958 Chappuis, PA. 1958. Le genre Parastenocaris Kessler. Vie Milieu, 8: 423432.  [Google Scholar] is designated as incertae sedis in Fontinalicaridinae Schminke, 2010 Schminke, HK. 2010. High-level phylogenetic relationships within Parastenocarididae (Copepoda, Harpacticoida). Crustaceana, 83: 343367. [Crossref], [Web of Science ®] [Google Scholar].  相似文献   
16.
研究了中等和重质量核的14MeV(n,t)反应截面的系统学特性.在考虑奇偶效应的基础上给出了反应截面的系统学公式和经验参数,利用这套参数计算了一些核素的反应截面,结果与测量值符合较好.并讨论了可能的反应机制和Q值效应.  相似文献   
17.
The research on Samarium-Neodymium isotope systematics of hydrothermal calcites from the Xikuangshan antimony deposit, Central Hunan, places precise timing constraints on the Sb mineralization in this area. It is revealed that the Xikuangshan deposit formed during the late Jurassic-early Cretaceous Period, the early- and latestage mineralization took place at (155.5± 1.1) Ma and (124.1±3.7) Ma, respectively. The accurate age determination of mineralization is very crucial for revealing the super-enrichment mechanism of the element Sb at the Xikuangshan mine, and lays some foundations for the further understandings of its ore genesis and mineralization mechanism.  相似文献   
18.
枝蕨纲是中泥盆世至早石炭世的一个重要的植物类群。作者对枝蕨纲代表植物进行了尝试性的分支系统学研究。枝蕨纲中可识别出伊瑞蕨目、瘤指蕨目和其他一些过渡类型。伊瑞蕨目和瘤指蕨目演化关系密切,二者分别以营养性末级附枝的顶端回弯和具瘤指蕨型的植物体组构为近裔共性。中国中上泥盆统的Metacladophyton和Polypetalophyton比伊瑞蕨目和瘤指蕨目进化程度要高,可能代表枝蕨纲内的一个新的高级分类单元,以具片化的末级附枝及次生生长为特征。伊瑞蕨目和瘤指蕨目出现在中泥盆世,而以Metacladophyton和Polypetalophyton为代表的进化类型出现在中泥盆世晚期至晚泥盆世早期。从伊瑞蕨目、瘤指蕨目到Metacladophyton和Polypetalophyton,侧生分枝系统显示了从三维的枝系统向似羽片状系统逐渐演化的趋势。  相似文献   
19.
多毛纲(Polychaeta)动物系统学的研究进展   总被引:1,自引:0,他引:1  
多毛纲动物以海洋底栖分布为主,在长期的进化过程中,产生了形形色色适应不同环境的形态特征和生活史策略.对其系统学的研究,有助于理解自然界生物多样性的保持机制及其在生物系统进化过程中所发挥的作用.从目前的研究结果来看,多毛纲动物为并系发生,但它们在环节动物系统发生树中的基部类群以及大部分并系群之间的相互关系仍有待确定.今后应该增加各类群有代表性的物种的取样数量,开展形态学特征、生活史策略以及分子遗传标记的综合研究,以期完善多毛纲动物的系统学.  相似文献   
20.
从研究种类和研究内容综述了双翅目蝇类的分子系统学研究进展,包括种群遗传变异及进化、种上阶元的系统发育分析、种及种下阶元的分类鉴定及分子进化4个方面内容.  相似文献   
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