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The oceanic water strider (or ocean‐skater) Halobates sericeus Eschscholtz has a disjunct distribution in the Pacific Ocean, with northern and southern populations widely separated by an equatorial zone. It is sensitive to sea surface conditions and, consequently, its distribution and population structure may provide an insight into environmental changes on the ocean surface on both recent and historical time scales. We assessed the genetic diversity and population structure of H. sericeus in the Pacific Ocean using three gene markers – cytochrome oxidase subunit I (COI), elongation factor 1α and internal transcribed spacer 1 (ITS‐1). These markers indicate that both populations are evolutionarily distinct with limited gene flow, having separated 20 000–50 000 years ago. This suggests that physical conditions and/or biotic interactions on the surface of the Pacific Ocean have provided significant barriers to gene flow since the late Pleistocene or earlier, creating biotic stability over large geographical and temporal scales in spite of a long history of global climate change. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 797–805.  相似文献   
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Fat is the prime energy source for birds during prolonged exercise, but protein is also catabolized. Estimates of the amount of catabolizable fat and protein (termed fat and protein fuel) are therefore important for studying energetics of birds. As fat and protein fuel can only be measured by sacrificing individuals or by use of technically complex methods, scoring systems were invented to estimate fat and protein fuel of birds in the field. The visible subcutaneous fat deposits and the thickness of the flight muscles are each scored on an ordinal scale but these scales do not correspond linearly to fat and protein fuel within species, which is needed for analyses such as flight range estimates. We developed an anova ‐type model to estimate fat and protein fuel from fat scores (FS) and muscle scores (MS) along with total mass and a size measurement. Using data from 11 337 individuals of eight passerine species (Common Nightingale Luscinia megarhynchos, Eurasian Reed Warbler Acrocephalus scirpaceus, Melodious Warbler Hippolais polyglotta, Willow Warbler Phylloscopus trochilus, Orphean Warbler Sylvia hortensis, Garden Warbler Sylvia borin, Common Whitethroat Sylvia communis, Subalpine Warbler Sylvia cantillans) mist‐netted in Mauritania, West Africa, we tested for independence of FS and MS and for variation in the relationship between scores and associated mass in response to physiological state. FS, MS and third primary length (size) explained variation in body mass of all eight species analysed (R2: 0.56–0.77). The parameter estimates of the model showed that fat and protein fuel increased monotonically with increasing fat and muscle scores. In two species we found small differences in the estimates between physiological states (seasons). We evaluated our model by comparing the predicted body mass of birds with both FS and MS equal to 0 with the mean body mass of individuals mist‐netted with both scores equal to zero. The values were very close. The amount of fat extracted from dead Garden and Willow Warblers was within the range of predicted fat fuel derived from the model. We conclude that our model is a useful non‐invasive method to estimate simultaneously mean fat and protein fuel of small passerines and we provide recommendations on its use.  相似文献   
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Ophion Fabricius is a diverse genus of nocturnal ichneumonid wasps (Insecta: Hymenoptera) that is particularly species‐rich in temperate areas, yet has received little taxonomic attention in the Holarctic region, where most species occur. While there have been some attempts to divide Ophion into monophyletic species groups, the vast majority of species have been lumped into a single, paraphyletic group, the O. luteus species group, which is defined only by the lack of characters specific to the other groups. The challenging morphology of this large catch‐all group has limited attempts to subdivide it, and no phylogenetic hypothesis has been proposed for the genus as a whole. In this study, we use DNA sequence data [28S ribosomal RNA (28S), cytochrome oxidase 1 (COI) and internal transcribed spacer 2 (ITS2)] to present the first molecular phylogeny of Ophion. We also describe the secondary structure of ITS2 for the first time in Ichneumonidae, and explore its implications for phylogeny estimation. We define 13 species groups, nine of which were previously considered part of the O. luteus species group s.l. The included species groups are the O. minutus, O. areolaris, O. scutellaris, O. flavidus, O. parvulus, O. slossonae, O. nigrovarius, O. pteridis, O. luteus s.s., and O. obscuratus species groups, along with three groups lacking described species (Species group 1, New Zealand group, Madagascar group). This study provides a framework for future studies of this diverse and morphologically challenging genus.  相似文献   
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S. HERZOG 《Animal genetics》1988,19(3):291-294
A study of 11 enzyme systems in blood samples of Cervus dama, C. elaphus, C. nippon and hybrids C. elaphus X nippon has revealed an erythrocyte 6-phosphogluconate dehydrogenase polymorphism in the hybrid populations. Genetic analysis suggests that this enzyme is controlled by one gene locus with two codominant alleles, one specific for pure Japanese sika deer, the other for pure red deer as well as for fallow deer, while both alleles have been found in the red X sika hybrids.  相似文献   
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Despite formal separation based on molecular and morphological evidence, the genera Prosthechea Knowles & Westc. and Encyclia Hook. have not been studied in terms of their vegetative anatomy. In this study we examine 16 Brazilian species of these genera. Additionally, one species of subtribe Laeliinae and another from subtribe Oncidiinae were studied in order to evaluate the taxonomic consistency of the anatomic characters observed. Except for Epidendrum crassifolium Lindl., all species possess a velamen differentiated into epivelamen and endovelamen. Endodermal cells with uniformly thickened walls, calcium oxalate raphides and cells with phi thickenings in the cortical region were observed in all species. Silica bodies, raphides and fibre bundles in the mesophyll were common in leaves of all species studied. By contrast, flavonoid crystals were observed in both roots and leaves of Prosthechea only. Encyclia is characterized by the presence of fibre bundles on the subepidermal layer, and a cuticle, which is clearly thicker than that of Prosthechea . These data strongly support the separation of Prosthechea and Encyclia .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 293–303.  相似文献   
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Abstract:  Cupuladriid cheilostome bryozoans can make new colonies both sexually and asexually. Sexual (aclonal) colonies are derived from larvae while asexual (clonal) colonies result from the fragmentation or division of larger colonies. A number of specialised morphologies exist which either enhance or discourage clonality, and cupuladriids preserve these in their skeletons, meaning that it is possible to count the abundances of individual modes of reproduction in fossil assemblages, and thus measure the mode and tempo of evolution of life histories using fossil colonies. In this paper we categorise, illustrate and describe the various clonal and aclonal methods of propagation in cupuladriids through the Cenozoic. Sexual reproduction is the only aclonal method of propagation, while four clonal methods are described comprising: (1) mechanical fragmentation, (2) autofragmentation, (3) colonial budding and (4) peripheral fragmentation. The processes involved in each are discussed and we explain how their prevalence can be measured in the fossil record using preservable morphologies. Compiling a record of the occurrence and distribution of the various modes of propagation through time and space we discover a general trend of evolution towards more complex modes in all three cupuladriid genera, but a geologically recent extinction of some modes of propagation that has left the present-day assemblage relatively depauperate. We see striking similarities in the general timing of expansion of modes of reproduction between the two most important genera, Cupuladria and Discoporella , although it is clear that Discoporella evolved a much wider range of special morphologies either to enhance or to discourage clonality than did Cupuladria .  相似文献   
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