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141.
Peter S Gillespie Laurence A Mound Chin-Ling Wang 《Australian Journal of Entomology》2002,41(2):111-117
A second Australian species of Parabaliothrips Priesner is described, P. newmani , forming male aggregations on the leaf buds of Moreton Bay fig, Ficus macrophylla (Moraceae). The genus, predominantly south-east Asian, is redefined and a key provided to the five described species. Members of this genus feed on leaves across a wide range of plant families, although each species is host specific. The host plant of the previously known Australian species, P. setifer Karny, is newly recognised as Leucopogon lanceolatus (Epacridaceae), and different south-east Asian species are associated with species of Betulaceae, Hamamelidaceae and Fagaceae. 相似文献
142.
The incidence and pattern of copollinator diversification in dioecious and monoecious figs 下载免费PDF全文
Li‐Yuan Yang Carlos A. Machado Xiao‐Dong Dang Yan‐Qiong Peng Da‐Rong Yang Da‐Yong Zhang Wan‐Jin Liao 《Evolution; international journal of organic evolution》2015,69(2):294-304
Differences in breeding system are associated with correlated ecological and morphological changes in plants. In Ficus, dioecy and monoecy are strongly associated with different suites of traits (tree height, population density, fruiting frequency, pollinator dispersal ecology). Although approximately 30% of fig species are pollinated by multiple species of fig‐pollinating wasps, it has been suggested that copollinators are rare in dioecious figs. Here, we test whether there is a connection between the fig breeding system and copollinator incidence and diversification by conducting a meta‐analysis of molecular data from pollinators of 119 fig species that includes new data from 15 Asian fig species. We find that the incidence of copollinators is not significantly different between monoecious and dioecious Ficus. Surprisingly, while all copollinators in dioecious figs are sister taxa, only 32.1% in monoecious figs are sister taxa. We present hypotheses to explain those patterns and discuss their consequences on the evolution of this mutualism. 相似文献
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144.
A 30-kDa protein extracted from the pericarpial portion of jelly fig (Ficus awkeotsang Makino) achenes has been identified as a thermostable chitinase based on its enzymatic activity. A cDNA fragment encoding the precursor protein (including a cleavable signal sequence) of this chitinase was obtained by PCR cloning, and subsequently confirmed by immunological recognition of its overexpressed protein in Escherichia coli. Homology modeling predicted that this thermostable chitinase in jelly fig achenes comprised a stable (betaalpha)(8) barrel fold with three pairs of disulfide linkage. Immunostaining indicated that this chitinase was exclusively localized in the pericarpial region but not in the seed cells where bulky protein bodies and massive oil bodies were accumulated. Spore germination of Colletotrichum gloeosporioides, a common post-harvest pathogen infecting ripening fruit of jelly fig and many other fruits, was inhibited by this chitinase purified from achenes. It is suggested that the biological function of the thermostable chitinase in the pericarp of jelly fig achenes is to protect the nutritive seeds from fungal attack during fruit ripening. 相似文献
145.
The Pacific Banyan in the Cook Islands: have its pollination and seed dispersal mutualisms been disrupted, and does it matter? 总被引:1,自引:0,他引:1
Fig trees (Ficus spp., Moraceae) are pollinated by species-specific fig wasps and have seeds that are mainly dispersed by fruit bats and birds. Consequently, they should be strongly dependent on mutualisms with animals for their reproductive success. As elsewhere in the Pacific, extinctions of potential seed dispersers have occurred on the islands in the southern Cook Islands archipelago. The abundance of the Pacific Banyan, Ficus prolixa, was found to be unrelated to the extent of potential seed disperser extinctions on different islands. There was no evidence of recruitment on Rarotonga, which has the most diverse bird and bat assemblage, and healthy populations on Mangaia, where all the native avian frugivores are extinct. Despite its very small population sizes on some of the islands, the trees pollinators are still present, showing that this mutualism has not yet been disrupted. Habitat loss, rather than a loss of mutualists, appears to be the main problem facing this species. 相似文献
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147.
低夜温后不同光强对榕树叶片PSⅡ功能和光能分配的影响 总被引:4,自引:0,他引:4
研究了自然低夜温后全光照与遮荫对榕树叶片PSⅡ功能及光能分配的影响。结果表明低夜温后全光照条件下叶片吸收光能分配于光化学反应部分减少,而热耗散部分和反应中心过剩光能则增加,从而导致了PSⅡ功能的下降,遮荫条件下光能分配于光化学反应的程度增加.虽然用于热耗散的比例下降了,但反应中心过剩光能相对较少,从而有利于PSⅡ功能的恢复。 相似文献
148.
Non-electrolyte permeability of plant cuticles: A critical evaluation of experimental methods 总被引:5,自引:0,他引:5
A method for measurement of non-electrolyte transport through enzymatically isolated cuticles of Ficus elastica Roxb. var. decora is presented. Permeance coefficients and hold-up times are determined under steady-state conditions. The transport system consists of two small reservoirs separated by the cuticle. The compounds tested (4-nitrophenol and pentachlorophenol) differ widely in lipid solubility and enable a critical evaluation of the apparatus used. The sorption capacity of the cuticle for lipophilic compounds is related to their cuticle/water partition coefficients. The problems of unstirred layers and of membrane integrity are discussed. The permeances measured ranged from 10−11 to 10−5 m s−1 , the hold-up times from 50 s to 22 h. 相似文献
149.
The leaves of the plant, Ficus exasperata Vahl. (Moraceae) are commonly used in the southern area of Nigeria and certain parts of Africa in reducing fever. This study was thus aimed at investigating this traditional use. 相似文献
150.
RONG WANG SIMON T. SEGAR MAXIMILIAN HARPER HUI YU RUPERT J. QUINNELL STEPHEN G. COMPTON 《Ecological Entomology》2015,40(4):428-436
1. Facilitation is recorded from diverse plant–insect interactions, including pollination and herbivory. 2. The significance of facilitation resulting from the behavior of males of multiple fig wasp species inside figs was investigated. Female fig wasps emerge from natal figs via exit holes dug by males, especially male pollinators. When no males are present, the females struggle to escape and may die. 3. Ficus microcarpa L. is a widely‐established invasive fig tree from Southeast Asia. Its pollinator is absent in South Africa, so the tree cannot reproduce, but two Asian non‐pollinating fig wasps (NPFW) Walkerella microcarpae and Odontofroggatia galili occupy its figs. Abundance patterns of the two NPFW and the proportion of male‐free figs in South Africa, Spain (where the pollinator is introduced), and in China, where the native fig wasp community is diverse, were compared to determine the consequences of reduced species richness for insect survival. 4. Female fig wasps in male‐free figs were found to be trapped, and small clutch sizes contributed to the absence of males in both species. The presence of pollinators in Spain allowed most NPFW to develop in figs containing males. Far more male‐free figs were present in South Africa, elevating mortality rates among female NPFW. Facilitation of female release by males of other NPFW species nonetheless benefitted the rarer species. 5. Selection pressures in South Africa currently favour greater aggregation of NPFW offspring and/or less female biased sex ratios. 相似文献