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ABSTRACT Although radiotelemetry is considered a valuable technique for ornithological field studies, several assumptions have been made about the impact that transmitters may have on the estimation of behavioral, ecological, and reproductive parameters. To assess the potential effects of backpack radiotransmitters, we captured and assigned 8 male American kestrels (Falco sparverius) into 2 groups: radiotagged (n = 6) and control individuals (leg-banded, n = 2). Thereafter, we collected feces approximately 2 hours after capture (day −1), and subsequently during days 0 (releasing day), 4, 7, 15, 30, 40, and 55. Prior to fecal analysis, we validated the corticosterone enzyme immunoassay using standard procedures (e.g., parallelism, dose-response curve), and we confirmed physiological significance of fecal glucocorticoid metabolites through adrenocorticotropin challenge, which induced an increase of 4-fold (446.10 ± 60.73 ng/g) above baseline (114.27 ± 15.23 ng/g) within 4 hours (P < 0.001). Both groups exhibited a significant increase in fecal glucocorticoids during day 0 (P < 0.001), but concentrations returned to preattachment values within 4 days. Fecal glucocorticoid concentrations did not differ between samples of radiotagged and leg-banded kestrels (P > 0.05). In spite of the small number of monitored subjects, these findings suggested that radiotransmitters did not affect adrenocortical activity in these male American kestrels.  相似文献   
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The delimitation of species is a major issue in systematic biology and has been a re-emerging discipline in the last decade. A number of studies have shown that the use of multiple data sets is critical for the identification of cryptic species, particularly in groups with complex evolutionary histories. Liolaemus monticola is a montane lizard species distributed in central Chile (32°–42°S), with four described subspecies in a latitudinal gradient from north to south: L. m. monticola , L. m. chillanensis , L. monticola ssp. and L. m. villaricensis . In order to test the systematic status and phylogenetic relationships of the taxa included in the L. monticola group, we analysed morphological (morphometric and meristic) and molecular (allozyme and mitochondrial DNA) data sets. The results of the morphological analyses showed that meristic variables correctly assigned individuals with higher accuracy than did morphometric characters. The results of the analyses of allozyme data revealed eight diagnostic loci that are evidence for significant differences among the four L. monticola subspecies. Phylogenetic analyses with mitochondrial DNA data, including additional species, showed that the L. monticola group is polyphyletic. We postulate that the four current subspecies represent independent evolutionary lineages and must be raised to the specific level as L. monticola , L. chillanensis and L. villaricensis . The taxonomic status of the unnamed L. monticola ssp. remains unresolved, although we provide a preliminary proposal.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 635–650.  相似文献   
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Avanzini, M., Piñuela, L. & García‐Ramos, J.C. 2011: Late Jurassic footprints reveal walking kinematics of theropod dinosaurs. Lethaia, Vol. 45, pp. 238–252. This study describes a set of theropod footprints collected from the Late Jurassic Lastres Formation (Asturias, N Spain). The footprints are natural casts (tracks and undertracks) grouped into three morphotypes, which are characterized by different size frequency, L/W relationship and divarication angles: ‘Grallatorid’ morphotype, ‘Kayentapus–Magnoavipes’ morphotype, ‘Hispanosauropus’ morphotype. The tracks were produced in firm, stiff and soft sediments. The infills of deep tracks, which are typically formed in soft mud, lack fine anatomical details, but they can reveal the walk kinematics of the trackmaker through the morphology of internal track fills and sinking traces. In all footprints, a horizontal outwardly directed translation movement and rotation are recognizable. The amount and geometry of digit penetration in the ground also show a pronounced difference. It can be inferred from the described sample that different theropoda‐related ichnogenera share common kinematics. □Asturias, dinosaur footprint, late jurassic, theropods, walking kinematics.  相似文献   
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We present a phylogenetic analysis that includes all known species of Agathemera, using as outgroup four species of the genera Heteronemia, Spinonemia, Monticomorpha, and Anisomorpha. Phylogenetic inference was based on three genes, 16S, COI (mitochondrial markers) and H3 (nuclear marker), based on the maximum‐parsimony, maximum‐likelihood and Bayesian inference methods. Our results show that the genus Agathemera is monophyletic; six of its eight species showed phylogenetic support, while the group A. claraziana + A. millepunctata was not resolved. The resulting topology shows two major clades, the first with A. maculafulgens, A. luteola, A. crassa, A. millepunctata, and A. claraziana, and the second including A. grylloidea, A. mesoauriculae, and A. elegans. Species of the first clade have large mesonotal processes and are found mainly east of the Andes, except for A. crassa. Members of the second clade have small or absent mesonotal processes and are distributed mainly to the west of the Andes. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 63–72.  相似文献   
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Coralliophilid gastropods include a large number of described species,grouped in at least seven to 10 'genera' according to their shellmorphology. They are considered closely related to Muricidaeand ranked as a family on its own or as a subfamily of muricids.Their phylogenetic position and relationships are still notdefined. The little anatomical work so far done on this groupseems to indicate a relatively high level of homogeneity, atleast in the alimentary system. There is a need for an independentphylogenetic framework to understand their position and relationshipwithin the muricoideans, and their internal systematics andphylogeny. We have addressed this problem by means of parsimonyanalysis of 609 aligned positions of the sequences coding forthe 12S rDNA. Four coralliophilid sequences representing thesame number of commonly recognized lineages (Babelomurex, Latiaxis,Coralliophila, Galeropsis = Quoyula) were analysed, along withthree sequences of muricoid genera (Stramonita, Phyllonotus,Nucella) representing as many subfamilies of Muricidae, plusthe sequence of the buccinoidean Fasciolaria as outgroup. Maximum parsimonyand neighbour-joining analysis of the dataset, with increasingweighing of transversions versus transitions, yielded similartopologies. Two major outcomes resulted from the analyses: first,the coralliophilid sequences included herein are always monophyletic,with very high bootstrap support in all analyses. This is inagreement with the few anatomical data gathered so far that suggestcoralliophilids are relatively homogeneous. Secondly, the sister-groupof the coralliophilids among the analysed sequences is representedby Stramonita, with high bootstrap support in all analyses.This is in a good agreement with previous molecular analyses andwith the morphological evidence that Rapaninae are the closest sistergroup of coralliophilids. According to the present results,the rank of the coralliophilids should be the same as Rapaninae,therefore a subfamilial status (Coralliophilinae) seems reasonable. (Received 14 August 2000; accepted 30 October 2000)  相似文献   
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Propanil is one of the major herbicides used on rice-paddies and is thought to produce adverse health effects through the action of its metabolite 3,4-dichloroaniline (3,4-DCA). T he feasibility of monitoring human exposure to propanil on the basis of 3,4-DCA adducts to haemoglobin (Hb) was investigated. We developed a method based on gas chromatography negative ion chemical ionization-mass spectrometry (NICI-GC-MS) to quantify 3,4-DCA released from human Hb after alkaline hydrolysis of the protein. 3,4-DCA-Hb adducts were identified in agricultural workers exposed to propanil and were detectable even 4 months after the last herbicide application. Urine samples collected at the same time had no measurable level of 3,4-DCA. 3,4-DCA-Hb adducts might be useful for monitoring human exposure to 3,4-DCA from agricultural sources.  相似文献   
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