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101.
The new damsel-dragonflies Zygokaratawia incompleta nov. sp. and Parazygokaratawia azari nov. gen., nov. sp., closely related to the campterophlebiid genus Zygokaratawia, are described from the Middle Jurassic locality of the Daohugou and Chentaizi villages, respectively (Ningcheng County, Inner Mongolia, NE China). Parazygokaratawia nov. gen. and Zygokaratawia share a narrowly reduced cubito-anal area, unique synapomorphy in the Isophlebioptera. Campterophlebiids with this character are only known from the Daohugou biota. 相似文献
102.
Abstract: A new monotypic aphid family, Sinojuraphididae, is described from the Middle Jurassic of China. Its antennae and wing venation have very plesiomorphic structures, even more than in known Triassic taxa (e.g. 12 antennomeres, Cu with a very long stem, very narrow pterostigma), confirming the persistence of ancient, probably Triassic, lineages among Jurassic aphids. 相似文献
103.
A new species of the fungus weevil genus Glaesotropis is described from the Late Eocene Rovno amber. G. diadiasashai sp. nov. differs from G. weitschati and G. minor described from Baltic amber in having a longer rostrum and in the structure of its antennae, with the third and fourth antennomeres being longer than the first and second ones. Additionally, the new species differs from G. weitschati in being smaller, in having unswollen frons, and weakly and smoothly concave elytral margin near hind coxae. The new species also differs from G. minor in having an uninterrupted posterior transverse carina on the pronotum, elytra less convex longitudinally, and a slightly broadened rostrum at the attachment of antennae. 相似文献
104.
陕西中三叠世中蝎蛉科两新属和新种(昆虫纲,长翅目) 总被引:2,自引:2,他引:0
记述中蝎蛉科Mesopanorpodidae 2新属、新种:Triassochoristites jinsuoguanensis gen.et sp.nov.,Forcinerva tongchuanensis gen.et sp.nov.化石标本采自陕西铜川中三叠世铜川组下段上部的灰绿色泥岩和页岩。这些新属、种系陕西昆虫群(陕西生物群的一个类别)铜川昆虫组合的新成员。铜川组的时代相当于欧洲拉丁尼期(Ladinian Stagc)。 相似文献
105.
The first complete mitochondrial genome of dobsonfly Protohermes concolorus Yang et Yang, 1988 (Megaloptera: Corydalidae) was sequenced in this study. The genome was a circular molecule of 15,851 bp
containing the typical 37 genes that arranged in the same order as that of the putative ancestor of hexapods. Sequences overlaps
were observed between several neighbor genes, which made the genome relatively compact. The tRNA-Ser (GCT) could not be folded
into typical secondary structure because its DHU arm was replaced with a simple loop. Six of the 13 protein genes were terminated
with a single T adjacent to a downstream tRNA gene in the same strand. The variation of GC content caused the different nucleotide
substitution patterns of the protein genes. The genome was AT-biased with a total A + T content of 75.83% which was also demonstrated
by the codon usage. The control region was the most AT-rich region with a sub-region of even higher A + T content. Protein
genes of two strands presented opposite CG-skew trends which was also reflected by the codon usage. For most of the amino
acids, the protein coding sequences did not prefer to use the cognate codons of corresponding tRNAs and the codon usage of
the protein genes was not random. The variation of nucleotide substitution patterns of protein genes was significantly correlated
with the GC content. The phylogenetic analyses based on all the 13 protein genes showed that Megaloptera was the sister group
of other holometabolous insects except Coleoptera. 相似文献
106.
107.
Rab11, an evolutionarily conserved, ubiquitously expressed subfamily of small monomeric Rab GTPases, has been implicated in
regulating vesicular trafficking through the recycling of endosomal compartment. In order to gain an insight into the role
of this gene in myogenesis during embryonic development, we have studied the expression pattern of Rab11 in mesoderm during
muscle differentiation in Drosophila embryo. When dominant-negative or constitutively active Drosophila Rab11 proteins are expressed or Rab11 is reduced via double-stranded RNA in muscle precursors, they cause partial failure
of myoblast fusion and show anomalies in the shape of the muscle fibres. Our results suggest that Rab11 plays no role in cell fate specification in muscle precursors but is required late in the process of myoblast fusion.
This work was supported by grants from the DST (to J.K.R.) and SRF from ICMR, New Delhi (to T.B.). 相似文献
108.
Isabelle Brigaud Xavier Grosmaître Marie-Christine François Emmanuelle Jacquin-Joly 《Cell and tissue research》2009,335(2):455-463
In insects, biogenic amines have been shown to play an important role in olfactory plasticity. In a first attempt to decipher the underlying molecular mechanisms, we report the molecular cloning and precise expression pattern of a newly identified octopamine/tyramine-receptor-encoding gene in the antennae of the noctuid moth Mamestra brassicae (MbraOAR/TAR). A full-length cDNA has been obtained through homology cloning in combination with rapid amplification of cDNA ends/polymerase chain reaction; the deduced protein exhibits high identities with previously identified octopamine/tyramine receptors in other moths. In situ hybridization within the antennae has revealed that MbraOAR/TAR is expressed at the bases of both pheromone-sensitive and non-sensitive olfactory sensilla and in cells with a neurone-like shape. In accordance with previous physiological studies that have revealed a role of biogenic amines in the electrical activity of the receptor neurones, our results suggest that biogenic amines (either octopamine or tyramine) target olfactory receptor neurones to modulate olfactory coding as early as the antennal level. 相似文献
109.
Nélia Varela Louise Couton César Gemeno Jesús Avilla Jean-Pierre Rospars Sylvia Anton 《Cell and tissue research》2009,337(3):513-526
The oriental fruit moth Cydia molesta is an important pest and the behavioural role of olfactory signals such as pheromones and plant volatiles have been studied
extensively in both sexes. To understand odour processing further, however, detailed knowledge of the anatomy of the olfactory
system is crucial. In the present study, an atlas of the antennal lobe (AL) is presented based on the three-dimensional reconstructions
of both ALs of three male and three female brains by means of neuroanatomical and computational approaches. We identified
48–49 "ordinary" glomeruli and one large glomerulus situated at the entrance of the antennal nerve in males, and 49–52 "ordinary"
glomeruli and one large glomerulus in the ventro-medial part of the AL in females. Anomalous supernumerary, anomalous missing
and sexually dimorphic glomeruli were found in the studied individuals in greater numbers than in other lepidopteran species.
Male and female maps were compared with respect to glomerular size and position with 45 glomeruli being matched, indicating
a conserved glomerular pattern between the sexes. Three additional glomeruli were sexually dimorphic in size and five male-specific
and six female-specific glomeruli were also found. Palp backfills resulted in the staining of a unique glomerulus in both
sexes identified as the sexually dimorphic glomerulus 45. This glomerulus was never stained from antennal backfills, which
stained the other glomeruli of the AL. The three-dimensional atlas can now be used to elucidate the functional role of individual
glomeruli in both sexes of C. molesta.
Nélia Varela and Louise Couton contributed equally to this work.
This study was supported by research grants from INRA (Projet Jeune Equipe and Projet S.P.E.) to S.A. and J.P.R. and by the
Spanish Ministry of Science and Technology (research grant AGL2004-05812/AGR to J.A. and C.G., Spanish Science and Education
Department, MEC). N.V. was financed by fellowship no. BES-2005-7605 (MEC, Spain). 相似文献
110.
The antennal lobe is the primary processing center for olfactory information in insects. To understand further the neural
circuitry of this brain area, we have investigated the distribution of γ-aminobutyric acid (GABA) and its colocalization with
neuropeptides in the antennal lobe of the noctuid moth Heliothis virescens. Immunocytochemical experiments with an antiserum against GABA showed a large number of labeled somata in the antennal lobe;
these somata were located exclusively in the lateral cell cluster. Stained neurites innervating all antennal-lobe glomeruli,
including the male-specific macroglomerular complex, suggested a prominent role of GABA in processing olfactory information,
including signals from pheromones, interspecifically acting odors, and plant odors. Fibers in two antennocerebral tracts (the
middle and dorsal antennocerebral tract) exhibited prominent GABA immunoreactivity. Double-labeling experiments revealed that
immunostaining for three neuropeptides, viz., A-type allatostatin, Manduca sexta allatotropin, and FMRFamide-related peptides, was largely colocalized with GABA in cell bodies of the lateral cell cluster.
The general absence of peptide immunostaining in the antennocerebral tracts strongly indicated that these peptides were colocalized
with GABA in local interneurons of the antennal lobe. In contrast, tachykinin-related peptides occurred in a distinct population
of local antennal-lobe neurons that did not exhibit GABA immunostaining. Thus, local interneurons that were not GABAergic
were present in the moth antennal lobe.
This work was supported by the Norwegian University of Science and Technology (project no. 80902101). 相似文献