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241.
Tim W. Clark 《西北部美国博物学家》2011,41(2)
Some relationships between home range, agonistic behavior, and reproductive patterns in thirteen-lined ground squirrels were investigated in Laramie Plains, Wyoming (August 1966–April 1969). Population size and densities fluctuated seasonally and annually. Adult male (N = 7) home ranges averaged 0.24 ha and were smaller than those of the female (N = 9), which averaged 0.35 ha. Agonistic interactions were more frequent during the natal period (late May–June) than during the breeding-gestation period (mid April–May). Most squirrels (86 percent) shared capture sites and had overlapping home ranges. However, a certain degree of spacing existed because of agonistic behavior. 相似文献
242.
243.
Thirty-nine previously unpublished reports of the endangered black-footed ferret from Wyoming are listed with dates, locations, number of animals, sources, and comments. 相似文献
244.
Jeroen Middelbeek Kristopher Clark Hanka Venselaar Martijn A. Huynen Frank N. van Leeuwen 《Cellular and molecular life sciences : CMLS》2010,67(6):875-890
The alpha-kinase family represents a class of atypical protein kinases that display little sequence similarity to conventional
protein kinases. Early studies on myosin heavy chain kinases in Dictyostelium discoideum revealed their unusual propensity to phosphorylate serine and threonine residues in the context of an alpha-helix. Although
recent studies show that some members of this family can also phosphorylate residues in non-helical regions, the name alpha-kinase
has remained. During evolution, the alpha-kinase domains combined with many different functional subdomains such as von Willebrand
factor-like motifs (vWKa) and even cation channels (TRPM6 and TRPM7). As a result, these kinases are implicated in a large
variety of cellular processes such as protein translation, Mg2+ homeostasis, intracellular transport, cell migration, adhesion, and proliferation. Here, we review the current state of knowledge
on different members of this kinase family and discuss the potential use of alpha-kinases as drug targets in diseases such
as cancer. 相似文献
245.
Lizard cells from the tails of geckos were readily morphologically and antigenically transformed in vitro by SV40 virus. Neither autografts of these cells nor allografts of SV40 transformed gecko embryo cells produced tumors in animals under observation for 1 to 3 years. 相似文献
246.
247.
Robert McFarland Kim M Clark Andrew A M Morris Robert W Taylor Sheila Macphail Robert N Lightowlers Douglass M Turnbull 《Nature genetics》2002,30(2):145-146
Mutations of mitochondrial DNA (mtDNA) are an important cause of genetic disease. We describe a family with an unusual homoplasmic mutation that resulted in six neonatal deaths and one surviving child with Leigh syndrome. The mother is clinically normal, but a severe biochemical and molecular genetic defect was present in both a fatally affected child and the mother. This family highlights the role of homoplasmic mt-tRNA mutations in genetic disease. 相似文献
248.
The identification of liquid ethane in Titan's Ontario Lacus 总被引:1,自引:0,他引:1
Brown RH Soderblom LA Soderblom JM Clark RN Jaumann R Barnes JW Sotin C Buratti B Baines KH Nicholson PD 《Nature》2008,454(7204):607-610
Titan was once thought to have global oceans of light hydrocarbons on its surface, but after 40 close flybys of Titan by the Cassini spacecraft, it has become clear that no such oceans exist. There are, however, features similar to terrestrial lakes and seas, and widespread evidence for fluvial erosion, presumably driven by precipitation of liquid methane from Titan's dense, nitrogen-dominated atmosphere. Here we report infrared spectroscopic data, obtained by the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini spacecraft, that strongly indicate that ethane, probably in liquid solution with methane, nitrogen and other low-molecular-mass hydrocarbons, is contained within Titan's Ontario Lacus. 相似文献
249.
Licatalosi DD Mele A Fak JJ Ule J Kayikci M Chi SW Clark TA Schweitzer AC Blume JE Wang X Darnell JC Darnell RB 《Nature》2008,456(7221):464-469
Protein-RNA interactions have critical roles in all aspects of gene expression. However, applying biochemical methods to understand such interactions in living tissues has been challenging. Here we develop a genome-wide means of mapping protein-RNA binding sites in vivo, by high-throughput sequencing of RNA isolated by crosslinking immunoprecipitation (HITS-CLIP). HITS-CLIP analysis of the neuron-specific splicing factor Nova revealed extremely reproducible RNA-binding maps in multiple mouse brains. These maps provide genome-wide in vivo biochemical footprints confirming the previous prediction that the position of Nova binding determines the outcome of alternative splicing; moreover, they are sufficiently powerful to predict Nova action de novo. HITS-CLIP revealed a large number of Nova-RNA interactions in 3' untranslated regions, leading to the discovery that Nova regulates alternative polyadenylation in the brain. HITS-CLIP, therefore, provides a robust, unbiased means to identify functional protein-RNA interactions in vivo. 相似文献
250.