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51.
A new species of Vitaceae is described and illustrated:Cissus pinnatifolia, the eighth species of the genus with pinnately compound leaves; an emended key to this group of species is also presented.  相似文献   
52.
Terrestricythere elisabethae sp. nov. is described from a semiterrestrial coastal habitat at two sites in Hampshire, southern England. It is the first record of a living population of the genus outside the Far East (north-west Pacific). Based on extensive collections and from observations of cultures, its morphology is described (including a formal definition of the unique 'visordont' hinge), as well as its ontogeny and lifestyle (encompassing habitat, life cycle, mode of life and locomotion). A further new species from Somerset, south-west England is also recorded on the basis of a single specimen but left in open nomenclature. The affinities of the Terrestricytheroidea are discussed in the context of a tentative phylogeny of podocopan Ostracoda. Both carapace and appendage characters are such as to warrant maintaining it as a separate superfamily, which is more closely related to the Cytheroidea and Darwinuloidea than to the Cypridoidea.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 253–288.  相似文献   
53.
Abstract. Dynamics of a Sequoia sempervirens forest in northern California were studied with long‐term plot data (1.44 ha) and recent transect data. The study was conducted in an old stand (> 1100 yr) on alluvial flats. Over three decades (1972–2001), changes in the composition and structure of the tree stratum were minor. Sequoia maintained a broad distribution of stem diameters throughout the period. Annual rates of Sequoia mortality (0.0029) and ingrowth (0.0029) were low, reflecting the great longevity of Sequoia and the slow canopy turnover of the study forest. Transect data also indicated a low frequency of canopy gap disturbance (≤ 0.4% of total land area per yr), but gap size was potentially large (> 0.1 ha) and the fraction of area in gaps (ca. 20%) was similar to other temperate forests. Regeneration quadrats sampled along transects, in gap centers, and on logs revealed that Sequoia regeneration is elevated at gap edges. The longevity of Sequoia and its response to gap disturbances ensure that it will remain a dominant species in the study forest.  相似文献   
54.
The paleontological history of Nypa, known today as the mangrovepalm, is traced through geological time back to the Late Cretaceous. Emphasis is laid on the New World occurrences, especially in NorthAmerica, where Nypa is known from fossil fruits and pollen. In SouthAmerica, the stratigraphic range of this palm extends from theMaastrichtian to the late Eocene, whereas in North America, Nypa isrestricted to only the Eocene. Nypa occurs as pollen all along theAmerican Gulf Coast from the early Eocene (Ypresian) to the late Eocene(Priabonian), while fruit records come from the early and middle Eoceneof Maryland and Texas, respectively. The floristics of these Eocenemangroves, including possible mangrove associates, and the developmentof mangrove vegetation in the neotropics through the Tertiary andQuaternary, are discussed. New paleobotanical evidence from a middleEocene faunal and floral assemblage in Texas, the Casa Blanca flora (LaredoFormation, Claiborne Group), which contains fossil Nypa pollen andfruits, is described in detail.  相似文献   
55.
《L'Anthropologie》2018,122(3):492-521
During the Upper Palaeolithic, especially in Gravettian times, the hunter-gatherer societies had an economy closely linked with the exploitation of two local species in Eastern Europe: reindeer and woolly mammoth. The ivory objects are rich archives about their ways of life and their collective imagination, as in particular the ivory female statuettes show. These figurines, also called “Venus”, are one of the cultural characteristics of the Gravettian sites. To date, although they are more numerous in Eastern Europe, they were discovered, in a variable number, also in site of Central and Western Europe; today, we have no clue that this cultural tradition crossed the Pyrenees. The corpus of pieces from the Gravettian sites of the Russian Plain (dated between 25,000 and 21,000 B.P.) is the more informative about technological know-how of the Gravettian craftsmen. He consists in the leading material of this paper, completed with some data about Epigravettian and Magdalenian statuettes. Whereas the Gravettian figurines show figurative female representations, those of the later cultural facies are more stylized. In a technological point of view, there is a close link between the choice of blanks within the mammoth tusk and the morphology of the statuettes, whatever the period of time considered.  相似文献   
56.
Chloroplast DNA (cpDNA) markers were developed that provided markers unique to a species or that delimited a large area within a species. These markers were then followed across two hybrid zones: Iris douglasiana/Iris∗∗∗ innominata, and Iris chrysophylla/Iris tenax. In each case the cline in haplotype frequency was compared to the cline for a morphologically based hybrid index. In all three transects across the I. douglasianall. innominata hybrid zone, the cpDNA cline was displaced 1-2 km relative to the morphologically defined hybrid zone; the displacement was not found in the other hybrid zone. The observed displacement represents introgression of cpDNA from ∗∗∗I. douglasiana into ∗∗∗I. innominata. It may be that the I. douglasiana/I.∗∗∗ innominata hybrid zone has shifted in recent time, leaving the slowly dispersing chloroplast DNA behind. The populations known as Iris thompsonii do not form a phylogenetic species and are best viewed as products of hybridization between ∗∗∗I. douglasiana and ∗∗∗I. innominata.  相似文献   
57.
Cunningham M.P., Brown C.G.D., Burridge M.J., Joyner L.P. and Purnell R.E. 1973. East Coast fever : the infectivity for cattle of infective particles of theileria parva harvested in various substrates. International Journal for Parasitology3: 335–338. Female Rhipicephalus appendiculatus ticks infected with Theileria parva were pre-fed on rabbits for 4 days before being removed and restrained on ‘plasticine’. They were then fed for 2-h periods on capillary tubes containing various substrates, the contents of which were subsequently inoculated into East Coast fever-susceptible cattle. Using this technique, precolostral calf serum and Eagle's Minimum Essential Medium, with the addition of Bovine Albumin Powder, were selected as substrates suitable for further laboratory investigation on East Coast fever as they were acceptable to the ticks and supported the viability of the parasites.  相似文献   
58.
Using an artificial feeding technique, infective particles of Theileria parva were harvested in bovine blood in capillary tubes from prefed female Rhipicephalus appendiculatus over a 2-hr period. Inoculations of this blood feed pool invariably resulted in the establishment of patent East Coast fever in autogeneic or syngeneic cattle, i.e., the blood donors or their monozygotic twins, but not in unrelated animals. Mechanical passage of 4 × 106 macroschizont-infected lymphoid cells, harvested from a heifer with East Coast fever, successfully induced patent theileriosis in the donor's monozygotic twin but not in a susceptible allogeneic bovid. The significance of parasite-cell association and histocompatibility of infected cells is discussed in relation to natural and mechanical transmission of Theileria parva.  相似文献   
59.
A new genus,Paraimene is established for a new Isopod species from the intertidal zone of Karachi Coast (Pakistan).Paraimene tuberculata sp. nov. is described and illustrated together with notes on the habitat of the species.  相似文献   
60.
Spatio‐temporal dynamics of phytoplankton and their relation to abiotic environmental factors in four rivers of south‐eastern Ivory Coast (Soumié, Eholié, Ehania and Noé) was analysed from July 2003 to March 2005. The pelagic zone of each river was sampled upstream and downstream. Phytoplankton abundance was higher in Noé River (154.3 104 cells l?1) and lower in Eholié river (23.05 104 cells l?1). Dominant taxa were Microcystis aeruginosa (Kütz.) Lemmerm. and Aphanocapsa incerta (Lemmerm.) Cronberg & Komárek. In general, minimum densities of phytoplankton were observed during the rainy season, while maximum were observed in dry season in the whole stations of the rivers studied, such periods corresponding to low and high concentrations of nitrates. Among the rivers surveyed, Eholié river seems to be the least disturbed because of its higher species diversity. Seasonality fluctuations of algae abundance appear to be influenced by the flow of water and nitrate levels. This work is a useful starting point for future research on micro algae in Ivory Coast.  相似文献   
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