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1.
Ecology of Plant‐Derived Smoke: Its Use in Seed Germination by Lara V Jefferson,Marcello Pennacchio and Kayri Havens with illustrations by David S. Sollenberger. Oxford and New York: Oxford University Press, 2014. xi + 316 pp, 18 b&w line diagrams. Hardback with dust jacket. ISBN 978‐0‐19‐975593‐6. £40. 下载免费PDF全文
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It has been suggested that three distinct genes,Abpa, Abpb, andAbpg, determine the three subunits of mouse salivary androgen-binding protein (ABP) (Dlouhy, S. R.,et al., Genetics
115, 535, 1987). We report the putative amino acid sequence of the subunit common to all forms of ABP, the Alpha subunit, and the partial amino acid sequence of the Beta subunit. These sequences have little in common, supporting the notion of at least two distinct genes coding for the subunits of the most common form of salivary ABP, the A:B dimer. A search of GenBank showed that these sequences have not been reported previously. The Beta subunit shows significant homology with helospectin, a member of the glucagon superfamily, but not enough homology to assign it to the family. No homology exists between ABP subunits and members of the ligand-binding carrier family of proteins nor does ABP show homology with other androgen-binding proteins. Particularly interesting is the observation that there is no relationship to rat prostatic steroid binding protein (PBP), given the similarities in protein tertiary structure, the numbers of subunits and their genes, and the earlier observation of ABP cross-reactive material in mouse prostate.Partial support for this work was provided by a PHS AREA award and by the Butler Academic Grants program. Both sources of support are greatly appreciated.A portion of this work constituted partial fulfillment of the honors thesis requirement for Butler University. 相似文献
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Anna Ougrinovskaia Rosemary S. Thompson Mary R. Myerscough 《Bulletin of mathematical biology》2010,72(6):1534-1561
Atherosclerosis is a chronic disease of the large arteries, characterized by fatty cholesterol-filled streaks and plaque build-up
within the artery wall. Within the past decade, inflammation has been determined as a crucial factor in all stages of lesion
formation, however, many of the mechanisms involved are not yet fully understood. We present a simplified ODE model that explores
the role of inflammation in atherosclerosis. The model incorporates two of the main lesion constituents, cholesterol-carrying
modified Low Density Lipoproteins (LDLs) and macrophage foam cells. Their complex interactions are combined into general functions,
and the long-term model behaviour is investigated through phase plane analysis and simulations. Our results indicate that
the underlying mechanisms of macrophage uptake of modified LDL can have a deep impact on the cellular dynamics in the lesion.
Our model demonstrates that it is macrophage proliferation and constant signalling to the endothelial cells, rather than an
increasing influx of modified LDL, that drives lesion instability. 相似文献
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Six carotenoids were identified in the leaves of Lilium hansonii, and of these, only two, namely β-carotene and 5,6-monoepoxy-β-carotene were found in the lily beetle. Further, 4-OH, 4,41-di-OH, and keto-carotenoids were found either in the larvae or in the adults of the beetle. As these were not found in its food plant, the insect must have been able to convert ingested carotenoids into these compounds. The presence of isozeaxanthin and absence of cantaxanthin in the larvae while both compounds were found in the adults suggest a precursor-product relationship. This is in agreement with possible pathways leading to the formation of keto-carotenoids. 相似文献
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Hannah Marie Wood Charles E. Griswold Rosemary G. Gillespie 《Cladistics : the international journal of the Willi Hennig Society》2012,28(6):598-626
Phylogenetic relationships among archaeid spider lineages, as well as the placement of archaeids within the Araneomorphae, present a problem in the systematics of spiders. We investigate these relationships by broadly sampling taxa from the Araneomorphae and superfamily Palpimanoidea, as well as from extant and fossil archaeid lineages. Using parsimony and Bayesian methods we perform a total‐evidence analysis that includes 126 morphological characters and over 4000 bases from one mitochondrial and three nuclear molecular markers. Phylogenetic analysis results in a delimitation of the superfamily Palpimanoidea to contain five families: Archaeidae, Mecysmaucheniidae, Stenochilidae, Palpimanidae and Huttoniidae. We also find the extant archaeids, which are restricted to the southern hemisphere, to be monophyletic, with the fossil archaeids paraphyletic. This phylogenetic framework is then used to interpret a novel morphological character, the highly modified and elevated cephalic area and elongated chelicerae (jaws), coupled with prey choice observations in the field and observations of chelicerae movements during predatory attacks. We conclude that the evolution of the elevated cephalic area, which reoriented the chelicerae muscles, led to highly manoeuvrable chelicerae and associated novel prey capture strategies. All members of Palpimanoidea appear to have modifications to the cephalic area, such as a diastema or sclerotization around the chelicerae bases, and furthermore, members appear to have evolved prey specialization. 相似文献
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