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971.
Stephen D. Petersen Tom Mason Sarah Akber Rick West Brad White Paul Wilson 《Conservation Genetics》2007,8(2):497-502
This paper outlines a novel, non-invasive procedure to obtain DNA from Mexican tarantulas (Brachypelma spp.) using exuvia. These species are important in the pet trade and species identification is important for international
wildlife law enforcement. Mitochondrial DNA sequence from the cytochrome c oxidase subunit I gene was used to investigate the relationship between various Brachypelma spp. This phylogeny was used as a framework to assign unknown specimens and spiderlings to species. The benefits to conservation,
research, and international wildlife law enforcement that are gained by the ability to accurately identify species without
the death of the specimen are explored. Our data also suggest that there is no support for the genus Brachypelmides as some authors have proposed and upholds the synonymy of Locht et al. (1999) J Arachnol 27:196–200. 相似文献
972.
Since the advent of strategies capable of manipulating the germline of mice, there has been a rapid expansion in the number of murine models of intestinal cancer. These have largely been developed with the specific aim of elucidating the molecular mechanisms underlying tumour initiation and progression. In attempting this goal, these models have become increasingly sophisticated, allowing ever more precise recapitulation of the genetic events that underlie human disease. Such technological advances include both temporal and spatial control over mutant allele expression. This review highlights some of notable recent advances using these approaches, with particular focus upon the role of a number of key signalling pathways, DNA repair mechanisms and inflammation. 相似文献
973.
van Hellemond JJ Hoek A Wichgers Schreur P Chupin V Ozdirekcan S Geysen D van Grinsven KW Koets AP Van den Bossche P Geerts S Tielens AG 《Eukaryotic cell》2007,6(9):1693-1696
Bloodstream form Trypanosoma theileri degrades glucose to acetate (47%) and succinate (45%) and, therefore, does not solely rely on glycolysis for ATP production. This trypanosomatid does not use amino acids for energy metabolism. These results refute the prevailing hypothesis that substrate availability determines the type of energy metabolism of trypanosomatids. 相似文献
974.
Headd JJ Ban YE Brown P Edelsbrunner H Vaidya M Rudolph J 《Journal of proteome research》2007,6(7):2576-2586
Herein, we study the interfaces of a set of 146 transient protein-protein interfaces in order to better understand the principles of their interactions. We define and generate the protein interface using tools from computational geometry and topology and then apply statistical analysis to its residue composition. In addition to counting individual occurrences, we evaluate pairing preferences, both across and as neighbors on one side of an interface. Likelihood correction emphasizes novel and unexpected pairs, such as the His-Cys pair found in most complexes of serine proteases with their diverse inhibitors and the Met-Met neighbor pair found in unrelated protein interfaces. We also present a visualization of the protein interface that allows for facile identification of residue-residue contacts and other biochemical properties. 相似文献
975.
976.
Jaeger PT Fleischmann KR Preece J Shneiderman B Wu PF Qu Y 《Biosecurity and bioterrorism : biodefense strategy, practice, and science》2007,5(4):335-345
Access to accurate and trusted information is vital in preparing for, responding to, and recovering from an emergency. To facilitate response in large-scale emergency situations, Community Response Grids (CRGs) integrate Internet and mobile technologies to enable residents to report information, professional emergency responders to disseminate instructions, and residents to assist one another. CRGs use technology to help residents and professional emergency responders to work together in community response to emergencies, including bioterrorism events. In a time of increased danger from bioterrorist threats, the application of advanced information and communication technologies to community response is vital in confronting such threats. This article describes CRGs, their underlying concepts, development efforts, their relevance to biosecurity and bioterrorism, and future research issues in the use of technology to facilitate community response. 相似文献
977.
978.
Leamey CA Merlin S Lattouf P Sawatari A Zhou X Demel N Glendining KA Oohashi T Sur M Fässler R 《PLoS biology》2007,5(9):e241
Binocular vision requires an exquisite matching of projections from each eye to form a cohesive representation of the visual world. Eye-specific inputs are anatomically segregated, but in register in the visual thalamus, and overlap within the binocular region of primary visual cortex. Here, we show that the transmembrane protein Ten_m3 regulates the alignment of ipsilateral and contralateral projections. It is expressed in a gradient in the developing visual pathway, which is consistently highest in regions that represent dorsal visual field. Mice that lack Ten_m3 show profound abnormalities in mapping of ipsilateral, but not contralateral, projections, and exhibit pronounced deficits when performing visually mediated behavioural tasks. It is likely that the functional deficits arise from the interocular mismatch, because they are reversed by acute monocular inactivation. We conclude that Ten_m3 plays a key regulatory role in the development of aligned binocular maps, which are required for normal vision. 相似文献
979.
MegaPlex PCR: a strategy for multiplex amplification 总被引:1,自引:0,他引:1
'MegaPlex PCR' is a robust technology for highly multiplexed amplification of specific DNA sequences. It uses target-specific pairs of PCR primers that are physically separated by surface immobilization. Initial surface-based amplification cycles are then coupled to efficient solution-phase PCR using one common primer pair. We demonstrate this method by co-amplifying and genotyping 75 unselected human single-nucleotide polymorphism (SNP) loci. 相似文献
980.
Although three-dimensional electron microscopy (3D-EM) permits structural characterization of macromolecular assemblies in distinct functional states, the inability to classify projections from structurally heterogeneous samples has severely limited its application. We present a maximum likelihood-based classification method that does not depend on prior knowledge about the structural variability, and demonstrate its effectiveness for two macromolecular assemblies with different types of conformational variability: the Escherichia coli ribosome and Simian virus 40 (SV40) large T-antigen. 相似文献