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1.
In this paper we carry out a taxonomic revision and phylogenetic analysis of the linyphiid spider genus Solenysa Simon, 1894. A total of 12 species is treated here, including five new species collected from China and Japan: Solenysa akihisai Tu sp. nov., Solenysa lanyuensis Tu sp. nov., Solenysa retractilis Tu sp. nov., Solenysa tianmushana Tu sp. nov. , and Solenysa yangmingshana Tu sp. nov. Solenysa circularis Gao, Zhu & Sha, 1993 is a junior synonym of Solenysa protrudens Gao, Zhu & Sha, 1993. We have assembled two different character matrices to reconstruct the phylogenetic relationships of Solenysa. In the first matrix (Matrix 1), five representative species of Solenysa were added to the morphological dataset of Miller & Hormiga to test the monophyly of the genus and its placement within Linyphiidae. The genitalic structures and somatic morphology of Solenysa were studied by means of scanning electron microscopy for the first time. To infer the species‐level phylogenetic relationships of Solenysa we produced a second matrix (Matrix 2) that includes all 12 Solenysa species and six outgroup species chosen from the results of the analysis of the first matrix. The two most parsimonious trees from the analysis of Matrix 1 support the monophyly of Solenysa and its placement within the ‘Distal Erigonines’ clade. The single most parsimonious tree resulting from the analysis of the second matrix suggests that the Solenysa clade includes four monophyletic groups, each group represented by a distinct genitalic pattern. The morphology of Solenysa, both somatic and genitalic, is highly autapomorphic. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 484–530.  相似文献   
2.
1. The objective was to identify the factors driving spatial and temporal variation in annual production (PA) and turnover (production/biomass) ratio (P/BA) of resident brown trout Salmo trutta in tributaries of the Rio Esva (Cantabrian Mountains, Asturias, north‐western Spain). We examined annual production (total production of all age‐classes over a year) (PA) and turnover (P/BA) ratios, in relation to year‐class production (production over the entire life time of a year‐class) (PT) and turnover (P/BT) ratio, over 14 years at a total of 12 sites along the length of four contrasting tributaries. In addition, we explored whether the importance of recruitment and site depth for spatial and temporal variations in year‐class production (PT), elucidated in previous studies, extends to annual production. 2. Large spatial (among sites) and temporal (among years) variation in annual production (range 1.9–40.3 g m?2 per year) and P/BA ratio (range 0.76–2.4 per year) typified these populations, values reported here including all the variation reported globally for salmonids streams inhabited by one or several species. 3. Despite substantial differences among streams and sites in all production attributes, when all data were pooled, annual (PA) and year‐class production (PT) and annual (P/BA) and year‐class P/BT ratios were tightly linked. Annual (PA) and year‐class production (PT) were similar but not identical, i.e. PT = 0.94 PA, whereas the P/BT ratios were 4 + P/BA ratios. 4. Recruitment (Rc) and mean annual density (NA) were major density‐dependent drivers of production and their relationships were described by simple mathematical models. While year‐class production (PT) was determined (R2 = 70.1%) by recruitment (Rc), annual production (PA) was determined (R2 = 60.3%) by mean annual density (NA). In turn, variation in recruitment explained R2 = 55.2% of variation in year‐class P/BT ratios, the latter attaining an asymptote at P/BT = 6 at progressively higher levels of recruitment. Similarly, variations in mean annual density (NA) explained R2 = 52.1% of variation in annual P/BA, the latter reaching an asymptote at P/BA = 2.1. This explained why P/BT is equal to P/BA plus the number of year‐classes at high but not at low densities. 5. Site depth was a major determinant of spatial (among sites) variation in production attributes. All these attributes described two‐phase trajectories with site depth, reaching a maximum at sites of intermediate depth and declining at shallower and deeper sites. As a consequence, at sites where recruitment and mean annual density reached minimum or maximum values, annual (PA) and year‐class production (PT) and annual (P/BA) and year‐class P/BT ratios also reached minimum and maximum values.  相似文献   
3.
The effect of stand age on soil respiration and its components was studied in a first rotation Sitka spruce chronosequence composed of 10‐, 15‐, 31‐, and 47‐year‐old stands established on wet mineral gley in central Ireland. For each stand age, three forest stands with similar characteristics of soil type and site preparation were used. There were no significant differences in total soil respiration among sites of the same age, except for the case of a 15‐year‐old stand that had lower soil respiration rates due to its higher productivity. Soil respiration initially decreased with stand age, but levelled out in the older stands. The youngest stands had significantly higher respiration rates than more mature sites. Annual soil respiration rates were modelled by means of temperature‐derived functions. The average Q 10 value obtained treating all the stands together was 3.8. Annual soil respiration rates were 991, 686, 556, and 564 g C m?2 for the 10‐, 15‐, 31‐, and 47‐year‐old stands, respectively. We used the trenching approach to separate soil respiration components. Heterotrophic respiration paralleled soil organic carbon dynamics over the chronosequence, decreasing with stand age to slightly increase in the oldest stand as a result of accumulated aboveground litter and root inputs. Root respiration showed a decreasing trend with stand age, which was explained by a decrease in fine root biomass over the chronosequence, but not by nitrogen concentration of fine roots. The decrease in the relative contribution of autotrophic respiration to total soil CO2 efflux from 59.3% in the youngest stand to 49.7% in the oldest stand was explained by the higher activity of the root system in younger stands. Our results show that stand age should be considered if simple temperature‐based models to predict annual soil respiration in afforestation sites are to be used.  相似文献   
4.
The ornate shrew (Sorex ornatus) is restricted to the vanishing wetlands of California, USA and Baja California, Mexico. Several subspecies of ornate shrews are considered ‘mammal species of special concern’ in California by the Department of Fish and Game, and one (Sorex ornatus relictus) has recently been listed as endangered. Populations of shrews around Buena Vista Lake have been diminished or extirpated due to habitat deterioration and human development. In order to study the patterns of genetic variation in isolated populations of Buena Vista Lake shrews, we developed 10 polymorphic microsatellite loci. There were 6–27 alleles per locus, and the loci had heterozygosity values that ranged from 20 to 80%. In addition, we screened 20 different populations of S. ornatus, eight species within two subfamilies of shrews (Soricinae and Crocidurinae), as well as in a mole (Talpidae, Neurotrichus gibbsii), to determine if these loci could be informative in other species as well.  相似文献   
5.
Five recombinant inbred lines obtained from the F2 generation of an interspecific cross between cultivar, Caimanta (Cai, Solanum lycopersicum) and wild accession, LA722 (P, S. pimpinellifolium) were crossed to obtain the second cycle hybrids (SCH). Eleven fruit quality traits were assessed in evaluating phenotypic variability among genotypes P, Cai, F1 (Cai × P), five RILs, and 10 SCH. One of the five recombinant inbred lines and three SCH had higher values than P, as the best genotype for shelf life. Sequence-related amplified polymorphism was used as the molecular method for detecting polymorphism among these 18 genotypes. The percentage of polymorphism in RILs and SCH was 61% and 66% respectively. Moreover, some bands detected in P were present in SCH. Several multivariate analyses were performed to find agreement between the phenotypic variability observed for fruit quality traits and the polymorphism obtained from sequence-related amplified polymorphism markers. A general Procrustes analysis estimated that there was a consensus proportion of 75% between phenotypic and molecular data. There was considerable preservation of some bands from the wild genotype, which could increase the variability in fruit quality traits in populations where the genetic diversity is limited.  相似文献   
6.
Muscarinic activation of tracheal smooth muscle (TSM) involves a M3AChR/heterotrimeric-G protein/NPR-GC coupling mechanism. G protein activators Mastoparan (MAS) and Mastoparan-7 stimulated 4- and 10-fold the NPR-GC respectively, being insensitive to PTX and antibodies against Gαi/o subfamily. Muscarinic and MAS stimulation of NPR-GC was blocked by antibodies against C-terminal of Gαq16, whose expression was confirmed by RT-PCR. However, synthetic peptides from C-terminal of Gαq15/16 stimulated the NPR-GC. Coupling of αq16 to M3AChR is supported by MAS decreased [3H]QNB binding, being abolished after M3AChR-4-DAMP-alkylation. Anti-i3M3AChR antibodies blocked the muscarinic activation of NPR-GC, and synthetic peptide from i3M3AChR (M3P) was more potent than MAS increasing GTPγ [35S] and decreasing the [3H]QNB activities. Coupling between NPR-GC and Gαq16 was evaluated by using trypsin-solubilized-fraction from TSM membranes, which displayed a MAS-sensitive-NPR-GC activity, being immunoprecipitated with anti-Gαq16, also showing an immunoreactive heterotrimeric-G-β -subunit. These data support the existence of a novel transducing cascade, involving Gαq16β γ coupling M3AChR to NPR-GC.  相似文献   
7.
The Chorote Indians are hunter-gatherers and fishermen from north-west Argentina and south-west Paraguay who belong to the Mataco-Maká linguistic family. Their edible plants are identified by botanical and vernacular names, the parts employed and modes of preparation and consumption. The Chorote people use 57 plant species as a source of food, which they consume in 118 different ways. Five new edible species, that yield seven plant foods, are reported here for the first time for Chaquenian ethnic groups. However, only a few wild plant foods are in frequent use today, with most being used occasionally, infrequently or not at all. A cross-cultural comparison with four neighbouring ethnic groups reveals that one third of their plant foods are exclusive to the Chorote people, despite the fact that they share most of their edible plants with the other groups. This article is the first contribution to an understanding of the Chorote's ethnobotany and to a comparison of interethnic relationships concerning their edible plant resources.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 73–85.  相似文献   
8.
9.
The genus Labulla Simon is circumscribed in phylogenetic terms to include the species Labulla thoracica (Wider), L. flahaulti Simon and L. machadoi sp. nov. The genital anatomy of the genus is described in detail and the taxonomy of the genus is reviewed. The monophyly of Labulla is supported by numerous morphological apomorphies of the male palp and female epigynum. Based on a cladistic analysis, a new genus, Pecado gen. nov. , is erected to place Labulla impudica Denis, from Northern Africa. Lepthyphantes insularis Saito and ' Labulla ' nepula Tikader, both formerly included in Labulla , are not congeneric with the type species of Labulla .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 359–404.  相似文献   
10.
This paper provides the first quantitative cladistic analysis of linyphiid morphology. Classical and novel homology hypotheses for a variety of character systems (male and female genitalia, somatic morphology, spinneret silk spigot morphology, etc.) are critically examined and studied within a phylogenetic context. Critical characters have been illustrated. A sample of linyphiid taxa (nine genera in four subfamilies), five species of Pimoa (Pimoidae), and two other araneoid families (Tetragnathidae and Araneidae, represented by Tetragnatha and Zygiella , respectively) were used to study the implications of the phylogeny of Pimoidae for the systematics of linyphiids. The phylogenetic relationships of these 16 exemplar taxa, as coded for the 47 characters studied, were analysed using numerical cladistic methods. In the preferred cladogram Pimoidae and Linyphiidae are sister groups, Stemonyphantinae are sister group to the remaining linyphiids, and Mynogleninae are sister group to the clade composed of Erigoninae plus Linyphiinae. These results agree with the relationships recently proposed by Wunderlich, except by finding erigonines as the sister group to linyphiines rather than to mynoglenines.  相似文献   
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