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81.
The order Thysanoptera (Paraneoptera), commonly known as thrips, displays a wide range of behaviours, and includes several pest species. The classification and suggested relationships among these insects remain morphologically based, and have never been evaluated formally with a comprehensive molecular phylogenetic analysis. We tested the monophyly of the suborders, included families and the recognized subfamilies, and investigated their relationships. Phylogenies were reconstructed based upon 5299 bp from five genetic loci: 18S ribosomal DNA, 28S ribosomal DNA, Histone 3, Tubulin‐alpha I and cytochrome oxidase c subunit I. Ninety‐nine thrips species from seven of the nine families, all six subfamilies and 70 genera were sequenced. Maximum parsimony, maximum likelihood and Bayesian analyses all strongly support a monophyletic Tubulifera and Terebrantia. The families Phlaeothripidae, Aeolothripidae, Melanthripidae and Thripidae are recovered as monophyletic. The relationship of Aeolothripidae and Merothripidae to the rest of Terebrantia is equivocal. Molecular data support previous suggestions that Aeolothripidae or Merothripidae could be a sister to the rest of Terebrantia. Four of the six subfamilies are recovered as monophyletic. The two largest subfamilies, Phlaeothripinae and Thripinae, are paraphyletic and require further study to understand their internal relationships. 相似文献
82.
Two hydroponic experiments were conducted to determine the effectsof brief and prolonged AI3+ exposures on the hydraulic conductivity(Lp) of northern red oak (Quercus rubra L.) root systems. RootLp was determined using the pressure chamber method of Fiscus(1977). In the first experiment, 28- to 40-d-old seedlings weretreated for 4 d with complete nutrient solutions containingone of three Al concentrations (0.04, 1.85 or 3.71 mol m3)and either 0 or 50 mmol m3 P. Neither Lp nor daily transpirationwas affected by treatment. In Experiment II, seedlings were grown for 4863 d incomplete solutions containing one of three Al concentrations(0, 0.75 or 2.00 mol m3) and either 10 or 250 mmol m3Ca. Lp and leaf area to root length ratio (LA/RL) were reducedwhen (AI3+/ Ca2+), the solution activity ratio, was 2.9 andhigher. Lp and LA/RL were also negatively correlated with Alconcentration and Al/Ca concentration ratio in the roots. Lpwas positively correlated with LA/RL in both experiments. Itis unclear whether Lp in the second experiment was reduced directlyby solution and root chemistry or whether Lp changed in responseto altered leaf/root balance. Key words: Al phytotoxicity, Al x Ca interaction, Quercus rubra, root hydraulic conductivity 相似文献
83.
84.
LAURENCE M. COOK ADRIAN M. RILEY IAN P. WOIWOD 《Biological journal of the Linnean Society. Linnean Society of London》2002,75(4):475-482
Changing patterns of morph frequency in three moth species ( Biston betularia , Odontoptera bidentata and Apocheima pilosaria ) have been investigated using data from the Rothamsted Insect Survey. All three exhibited industrial melanism during the period of high atmospheric pollution in Britain. Three historical and habitat types are compared, the old industrial north of England, rural Scotland, Wales and South-West England, and a southern English intermediate region of high human population density but generally low industrialization. Between 1974 and 1999 the carbonaria morph of B. betularia declined in frequency in the industrial region and is nearly absent from rural areas. It is the form which most closely tracks atmospheric change. It is shown that the insularia forms of B. betularia and the melanic morphs in the other two species have decreased in the industrial region, commencing later than carbonaria , but have maintained their presence and possibly reached equilibrium elsewhere. They may be non-industrial polymorphisms. B. betularia is rarer than the other species and all three species are at lower densities in industrial than in non-industrial regions. © 2002 The Linnean Society of London , Biological Journal of the Linnean Society , 2002, 75 , 475–482. 相似文献
85.
The systematic relationships between phlaeothripine Thysanoptera species suggest that moss-feeding is an uncommon and highly derived habit. It is restricted to a single sub-tribe, the Williamsiellina, which includes two genera, Lissothrips with 17 species and Williamsiella with 25 species. Although widely distributed, these genera are particularly common in the New World. Structural variation within and between populations of these small wingless insects is discussed and the conclusion reached that species cannot be defined satisfactorily in the common North American L. muscorum -group without experimental rearing. Trisclerothrips is synonymized with Lissothrips , and Prolissothrips, Microlissothrips and Phthirothrips are synonymized with Williamsiella . One specific synonym is established, and four new species are described: L. clayae from Trinidad, L. okajimai from Japan, W. tambopata from Peru and W. zaps from Fiji. 相似文献
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87.
Abstract A phylogenetic analysis of the Melanthripidae genus Cranothrips Bagnall is presented. A data matrix with continuous and discrete characters was analysed under parsimony criteria. Continuous and discrete characters were analysed, separately and in combination. When the different blocks of characters were analysed separately, important differences in tree topologies occurred. The optimal tree obtained from discrete characters alone was similar to the tree resulting from total evidence. For most groups, the support values resulting from all the evidence analysis were higher than those obtained from the discrete‐only analysis. Two new species from Australia are described and illustrated, Cranothrips ibisca sp.n. and Cranothrips conostylus sp.n. A key to the 12 species in the genus is provided. Additionally, the host associations and the distributional patterns of the four worldwide genera of Melanthripidae are discussed. 相似文献
88.
蓟马采集和玻片标本的制作 总被引:18,自引:0,他引:18
介绍蓟马标本的采集方法、常规鉴定用的临时性玻片和存档及分类用的永久性玻片标本的制作方法。标本的采集主要是拍打植物花朵、叶片及枯枝,玻片的制作重点介绍了制作存档和分类用的永久性玻片的5个步骤,即浸解脱色、洗涤、脱水、整姿封盖和干燥。 相似文献
89.
90.
LAURENCE DR 《Proceedings of the Royal Society of Medicine》1958,51(12):1000-1002