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81.
Serris-Les Ruelles is an early medieval demesne (manor house) showing the bipartite structure which is typical of this kind
of landed property. The organisation is based on social difference: on the one hand the lord in his manor house, on the other
the peasant in their village. The difference is apparent from the inorganic remains. Two out of four possible criteria were
applied to investigate whether the difference is also apparent in plant food. The result of the investigation was negative.
The reason might be that the spatial and economic separation between lord and peasant was not yet wide enough where food was
concerned. 相似文献
82.
83.
George Papageorgiou David Ogden John E T Corrie 《Photochemical & photobiological sciences》2008,7(4):423-432
A new version of a benzophenone antenna-sensitised photolabile derivative of l-glutamate, which has a dicarboxylic acid substituent on the benzophenone to promote water solubility, has been synthesised. It does not show problems of precipitation in the presence of calcium ions that were encountered with related compounds in which one or two phosphate groups were present as water-solubilising substituents but retains the enhanced photolytic efficiency that results from the benzophenone antenna. Photolysis of the compound proceeds with stoichiometric release of l-glutamate and pharmacological evaluations have shown that the compound itself has no evidence of agonist or antagonist activity in its unphotolysed form. 相似文献
84.
Novel approach to heritability detection suggests robustness to paternal genotype in a complex morphological trait
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Max E. Winston Andrea Thompson Gabriel Trujillo Andrew T. Burchill Corrie S. Moreau 《Ecology and evolution》2017,7(12):4179-4191
Heritable variation is essential for evolution by natural selection. In Neotropical army ants, the ecological role of a given species is linked intimately to the morphological variation within the sterile worker caste. Furthermore, the army ant Eciton burchellii is highly polyandrous, presenting a unique opportunity to explore heritability of morphological traits among related workers sharing the same colonial environment. In order to exploit the features of this organismal system, we generated a large genetic and morphological dataset and applied our new method that employs geometric morphometrics (GM) to detect the heritability of complex morphological traits. After validating our approach with an existing dataset of known heritability, we simulated our ability to detect heritable variation given our sampled genotypes, demonstrating the method can robustly recover heritable variation of small effect size. Using this method, we tested for genetic caste determination and heritable morphological variation using genetic and morphological data on 216 individuals of E. burchellii. Results reveal this ant lineage (1) has the highest mating frequency known in ants, (2) demonstrates no paternal genetic caste determination, and (3) suggests a lack of heritable morphological variation in this complex trait associated with paternal genotype. We recommend this method for leveraging the increased resolution of GM data to explore and understand heritable morphological variation in nonmodel organisms. 相似文献
85.
Piotr Łukasik Justin A. Newton Jon G. Sanders Yi Hu Corrie S. Moreau Daniel J. C. Kronauer Sean O'Donnell Ryuichi Koga Jacob A. Russell 《Molecular ecology》2017,26(14):3808-3825
Symbiotic bacteria play important roles in the biology of their arthropod hosts. Yet the microbiota of many diverse and influential groups remain understudied, resulting in a paucity of information on the fidelities and histories of these associations. Motivated by prior findings from a smaller scale, 16S rRNA‐based study, we conducted a broad phylogenetic and geographic survey of microbial communities in the ecologically dominant New World army ants (Formicidae: Dorylinae). Amplicon sequencing of the 16S rRNA gene across 28 species spanning the five New World genera showed that the microbial communities of army ants consist of very few common and abundant bacterial species. The two most abundant microbes, referred to as Unclassified Firmicutes and Unclassified Entomoplasmatales, appear to be specialized army ant associates that dominate microbial communities in the gut lumen of three host genera, Eciton, Labidus and Nomamyrmex. Both are present in other army ant genera, including those from the Old World, suggesting that army ant symbioses date back to the Cretaceous. Extensive sequencing of bacterial protein‐coding genes revealed multiple strains of these symbionts coexisting within colonies, but seldom within the same individual ant. Bacterial strains formed multiple host species‐specific lineages on phylogenies, which often grouped strains from distant geographic locations. These patterns deviate from those seen in other social insects and raise intriguing questions about the influence of army ant colony swarm‐founding and within‐colony genetic diversity on strain coexistence, and the effects of hosting a diverse suite of symbiont strains on colony ecology. 相似文献
86.
Lu Wen-Chi Corrie Lauren J. Chapman Erin E. Reardon 《Environmental Biology of Fishes》2008,82(1):41-49
This study quantifies the behavioral response of the widespread mouth brooding African cichlid Pseudocrenilabrus multicolor victoriae to progressive hypoxia. We exposed four gender/stage classes of P. multicolor (males, brooding females, females that had just released young, and non-brooding females) to progressive hypoxia and recorded
the percent time spent using aquatic surface respiration (surface skimming, ASR) and gill ventilation rates. This was done
for fish collected from three sites in Uganda (lake, swamp, and river) after long-term acclimation to normoxia. There was
no effect of site of origin on response to hypoxia, but ASR thresholds did differ between gender/stage classes. The oxygen
level (threshold) at which spent 10, 50, and 90% of their time at the surface using ASR was much higher for brooding females
than for males, whereas ASR thresholds did not differ between non-brooding females and males. Similarly, the level at which
ASR was initiated was much higher in brooding females than males, but did not differ between males and non-brooders, or between
males and females than had just released young. The rate of gill ventilation dropped significantly in males and all stages
of females after initiation of ASR, suggesting that surface skimming increases efficiency of oxygen acquisition. These results
suggest that mouth brooding in female P. multicolor ASR improves oxygen uptake but imposes a cost in terms of time spent at the water surface, and this may affect maternal predation
risk in low-oxygen habitats. 相似文献
87.
Commercially-available sulforhodamine sulfonyl chlorides contain two isomeric monosulfonyl chlorides. Conjugates of these isomers with amines have different properties because the sulfonamide formed from one isomer can undergo ring-closure to a colorless sultam. This chemistry has been examined for a model conjugate with methylamine and for a bioconjugate with 2'(3')-O-[N-(2-aminoethyl)carbamoyl]ATP. The interaction of each isomer of the latter conjugates with myosin subfragment 1 has been characterized. Significant differences between the two isomers are observed in these interactions. 相似文献
88.
Nanthakumar NN Klopcic CE Fernandez I Walker WA 《American journal of physiology. Regulatory, integrative and comparative physiology》2003,285(1):R162-R170
The aim of this study was to determine whether intestinal xenografts could recapitulate human in utero development by using disaccharidases as markers. Twenty-week-old fetal intestine was transplanted into immunocompromised mice and was followed. At 20-wk of gestation, the fetal human intestine was morphologically developed with high sucrase and trehalase but had low lactase activities. By 9-wk posttransplantation, jejunal xenografts were morphologically and functionally developed and were then monitored for =6 mo. Both sucrase and trehalase activities remained unchanged, but lactase activity increased in a manner similar to that described in in utero development. Changes in sucrase and lactase activities were paralleled by protein levels. Cortisone acetate treatment at 20-wk posttransplantation accelerated the ontogeny of lactase but did not alter sucrase and trehalase activities. Biopsies from 1- and 2-yr-old infant intestine showed that all activities, except trehalase in the proximal intestine, corresponded to the levels found in jejunal xenografts at 24 wk posttransplantation. These studies suggest that 20-wk-old fetal intestine has the extrauterine developmental potential to follow normal intrauterine ontogeny as a xenograft. 相似文献
89.
The grape phylloxera, Daktulosphaira vitifoliae, is a viticultural pest that in the past has devastated vineyards worldwide, yet little is known about this insect's biology. The genetic structure of Australian populations of grape phylloxera and its mode of reproduction were studied following the development of four polymorphic microsatellite loci. Insects were collected from 28 vineyards, with a total of 361 insects included in the study. The majority of vineyards were infested by functionally parthenogenetic lineages of grape phylloxera that inhabit the root system and there was little support for the traditionally described holocyclic life cycle for this species. Clonal diversity was limited in all of the vineyard regions, with the exception of the Rutherglen region. A multiple founder scenario or occasional sex may contribute to diversity within the Rutherglen region. Leaf galling populations comprised classes distinct from the common genotypic classes identified on the roots, suggesting limited exchange between these groups. Implications for the management of D. vitifoliae are discussed. 相似文献
90.
A new caged proton, 1-(2-nitrophenyl)ethyl sulfate (caged sulfate), is characterized by infrared spectroscopy and compared with a known caged, proton 2-hydroxyphenyl 1-(2-nitrophenyl)ethyl phosphate (caged HPP). In contrast to caged HPP, caged sulfate can induce large pH jumps and protonate groups that have pK values as low as 2.2. The photolysis mechanism of caged sulfate is analogous to that of P(3)-[1-(2-nitrophenyl)ethyl] ATP (caged ATP), and the photolysis efficiency is similar. The utility of this new caged compound for biological studies was demonstrated by its ability to drive the acid-induced conformational change of metmyoglobin. This transition from the native conformation to a partially unfolded form takes place near pH 4 and was monitored by near-UV absorption spectroscopy. 相似文献