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101.
EVA TÓTH J. EMMETT DUFFY 《Biological journal of the Linnean Society. Linnean Society of London》2008,94(3):527-540
Eusocial societies are defined by a reproductive division of labour between breeders and nonbreeders that is often accompanied by morphological differentiation. Some eusocial taxa are further characterized by a subdivision of tasks among nonbreeders, often resulting in morphological differentiation among different groups (subcastes) that specialize on different sets of tasks. We investigated the possibility of morphological castes in eusocial shrimp colonies ( Zuzalpheus , formerly part of Synalpheus ) by comparing growth allometry and body proportions of three eusocial shrimp species with three pair-forming species (species where reproductive females and males occur in equal sex ratios). Allometry of eusocial species differed in several respects from that of pair-forming species in both lineages. First, allometry of fighting claw size among individuals other than female breeders was steeper in eusocial than in pair-forming species. Second, breeding females in eusocial colonies had proportionally smaller weapons (fighting claws) than females in pair-forming species. Finally, claw allometry changed with increasing colony size in eusocial species; large colonies showed a diphasic allometry of fighting claw and finger size, indicating a distinctive group of large individuals possessing relatively larger weapons than other colony members. Shrimp are thus similar to other eusocial animals in the morphological differentiation between breeders and nonbreeders, and in the indication that some larger nonbreeders might contribute more to defence than others. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 527–540. 相似文献
102.
P. TRIGAS TH. CONSTANTINIDIS T. TOULOUMENIDOU 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(4):762-774
Centaurea carystea Trigas & Constantin., a new yellow‐flowered species of Centaurea from Mt. Ochi on Evvia Island (Greece), is described and illustrated. It is a member of the polymorphic C. section Acrolophus and allied to taxa of the C. attica aggregate, C. pelia and C. mantoudii. The new species appears to be a local and threatened endemic, with the total number of individuals known being less than 500. A karyological examination revealed that it is hexaploid, with 2n = 6x = 54, an unusual number in Centaurea, which may indicate a hybrid origin. To further clarify the taxonomic position of C. carystea , we used random amplification of polymorphic DNA markers of 25 plants belonging to nine species, subspecies and varieties morphologically related to the new species, together with two reference taxa. Clustering using the unweighted pair group method with arithmetic mean indicated a discrete position for C. carystea , close to but distinct from the yellow‐flowered C. mantoudii. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 762–774. 相似文献
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104.
Background
Automated microscopy technologies have led to a rapid growth in imaging data on a scale comparable to that of the genomic revolution. High throughput screens are now being performed to determine the localisation of all of proteins in a proteome. Closer to the bench, large image sets of proteins in treated and untreated cells are being captured on a daily basis to determine function and interactions. Hence there is a need for new methodologies and protocols to test for difference in subcellular imaging both to remove bias and enable throughput. Here we introduce a novel method of statistical testing, and supporting software, to give a rigorous test for difference in imaging. We also outline the key questions and steps in establishing an analysis pipeline. 相似文献105.
106.
A highly selective two-stage isolation method for the enumeration of Staphylococcus aureus in foods 总被引:5,自引:3,他引:2
B.K. ISIGIDI L.A. DEVRIESE† TH. CROEGAERT J. VAN HOOF 《Journal of applied microbiology》1989,66(5):379-384
A plate method for enumerating Staphylococcus aureus is described which combines a 1-h recovery period for stressed cells on a relatively non-selective Baird-Parker agar base followed by a 24-h growth phase in a highly selective, supplemented Baird-Parker medium added as an overlay. Tests with pure cultures showed satisfactory recovery of stressed Staph. aureus and other bacteria. Similar results were obtained with the conventional Baird-Parker procedure and with the two-stage isolation method for shrimps and poultry neck skins, but for raw minced meat, recoveries were higher with the combined method than with the conventional medium.
All colonies visible after 24 h on the two-stage medium can be counted as Staph. aureus , whereas longer incubation times and confirmatory tests are necessary to differentiate it from other organisms on conventional Baird-Parker medium. 相似文献
All colonies visible after 24 h on the two-stage medium can be counted as Staph. aureus , whereas longer incubation times and confirmatory tests are necessary to differentiate it from other organisms on conventional Baird-Parker medium. 相似文献
107.
Lord K Moll D Lindsey JK Mahne S Raman G Dugas T Cormier S Troxlair D Lomnicki S Dellinger B Varner K 《Journal of receptor and signal transduction research》2011,31(2):157-167
Exposure to airborne particles is associated with increased cardiovascular morbidity and mortality. During the combustion of chlorine-containing hazardous materials and fuels, chlorinated hydrocarbons chemisorb to the surface of transition metal-oxide-containing particles, reduce the metal, and form an organic free radical. These radical-particle systems can survive in the environment for days and are called environmentally persistent free radicals (EPFRs). This study determined whether EPFRs could decrease left ventricular function before and after ischemia and reperfusion (I/R) in vivo. Male Brown-Norway rats were dosed (8?mg/kg, intratracheal) 24?h prior to testing with particles containing the EPFR of 1, 2-dichlorobenzene (DCB230). DCB230 treatment decreased systolic and diastolic function. DCB230 also produced pulmonary and cardiac inflammation. After ischemia, systolic, but not diastolic function was significantly decreased in DCB230-treated rats. Ventricular function was not affected by I/R in control rats. There was greater oxidative stress in the heart and increased 8-isoprostane (biomarker of oxidative stress) in the plasma of treated vs. control rats after I/R. These data demonstrate for the first time that DCB230 can produce inflammation and significantly decrease cardiac function at baseline and after I/R in vivo. Furthermore, these data suggest that EPFRs may be a risk factor for cardiac toxicity in healthy individuals and individuals with ischemic heart disease. Potential mechanisms involving cytokines/chemokines and/or oxidative stress are discussed. 相似文献
108.
109.
Sofia Exarchou Ulf Lindstr?m Johan Askling Jonas K Eriksson Helena Forsblad-d’Elia Martin Neovius Carl Turesson Lars Erik Kristensen Lennart TH Jacobsson 《Arthritis research & therapy》2015,17(1)
IntroductionPrevalence estimates of ankylosing spondylitis vary considerably, and there are few nationwide estimates. The present study aimed to describe the national prevalence of clinically diagnosed ankylosing spondylitis in Sweden, stratified according to age, sex, geographical, and socio-economic factors, and according to subgroups with ankylosing spondylitis-related clinical manifestations and pharmacological treatment.MethodsAll individuals diagnosed with ankylosing spondylitis according to the World Health Organization International Classification of Disease codes, between 1967 and 2009, were identified from the National Patient Register. Data regarding disease manifestations, patient demographics, level of education, pharmacological treatment, and geographical region were retrieved from the National Patient Register and other national registers.ResultsA total of 11,030 cases with an ankylosing spondylitis diagnosis (alive, living in Sweden, and 16 to 64 years old in December 2009) were identified in the National Patient Register, giving a point prevalence of 0.18% in 2009. The prevalence was higher in northern Sweden, and lower in those with a higher level of education. Men had a higher prevalence of ankylosing spondylitis (0.23% versus 0.14%, P < 0.001), a higher frequency of anterior uveitis (25.5% versus 20.0%, P < 0.001) and were more likely to receive tumor necrosis factor inhibitors than women (15.6% versus 11.8% in 2009, P < 0.001). Women were more likely than men to have peripheral arthritis (21.7% versus 15.3%, P < 0.001), psoriasis (8.0% versus 6.9%, P = 0.03), and treatment with oral corticosteroids (14.0% versus 10.4% in 2009, P < 0.001).ConclusionThis nationwide, register-based study demonstrated a prevalence of clinically diagnosed ankylosing spondylitis of 0.18%. It revealed phenotypical and treatment differences between the sexes, as well as geographical and socio-economic differences in disease prevalence.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0627-0) contains supplementary material, which is available to authorized users. 相似文献110.
Thomas M. Newsome Guy‐Anthony Ballard Mathew S. Crowther Justin A. Dellinger Peter J. S. Fleming Alistair S. Glen Aaron C. Greenville Chris N. Johnson Mike Letnic Katherine E. Moseby Dale G. Nimmo Michael Paul Nelson John L. Read William J. Ripple Euan G. Ritchie Carolyn R. Shores Arian D. Wallach Aaron J. Wirsing Christopher R. Dickman 《Restoration Ecology》2015,23(3):201-208
There is global interest in restoring populations of apex predators, both to conserve them and to harness their ecological services. In Australia, reintroduction of dingoes (Canis dingo) has been proposed to help restore degraded rangelands. This proposal is based on theories and the results of studies suggesting that dingoes can suppress populations of prey (especially medium‐ and large‐sized herbivores) and invasive predators such as red foxes (Vulpes vulpes) and feral cats (Felis catus) that prey on threatened native species. However, the idea of dingo reintroduction has met opposition, especially from scientists who query the dingo's positive effects for some species or in some environments. Here, we ask ‘what is a feasible experimental design for assessing the role of dingoes in ecological restoration?’ We outline and propose a dingo reintroduction experiment—one that draws upon the existing dingo‐proof fence—and identify an area suitable for this (Sturt National Park, western New South Wales). Although challenging, this initiative would test whether dingoes can help restore Australia's rangeland biodiversity, and potentially provide proof‐of‐concept for apex predator reintroductions globally. 相似文献