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371.
372.
Lesser Prairie-Chicken ( Tympanuchus pallidicinctus ) populations have experienced dramatic rangewide declines (up to 92%) since settlement of the Great Plains. This decline has been attributed to changes in land-use practices, such as conversion of native rangelands to intensive agriculture and increased grazing pressure. These changes may increase the impact of interspecific competition on populations. We documented disturbance of lekking Lesser Prairie-Chickens by Ring-necked Pheasants ( Phasianus colchicus ). Future management and research should take into account possible impacts to Lesser Prairie-Chickens during the breeding season.  相似文献   
373.
The swift fox ( Vulpes velox ) was classified in 1995 as a candidate for listing under the Endangered Species Act. Since then, several studies have addressed survey methods for monitoring swift fox populations. The purpose of this paper is to assist field researchers in documenting the presence of swift foxes by identification of recently active den sites. We propose that swift foxes have unique external den characteristics that can be distinguished during aerial surveys. We collected data from 30 swift fox den complexes on both continuous rangeland and landscapes fragmented by cropland in northwest Texas. There were no differences in den characteristics between landscape types ( P > 0.10). The number of openings per den ranged from 1 to 8 and had an average opening height of 20 cm. As number of openings increased, the maximum distance between openings also increased ( r = 0.88, P Canis latrans ) and red foxes ( Vulpes vulpes ), 2 species that can be sympatric with swift foxes. We suggest that aerial den searching followed by ground verification may be an effective technique for determining presence of swift foxes in areas of short-grass prairies and fragmented habitats.  相似文献   
374.
Clinical responses to anticancer therapies are often restricted to a subset of patients. In some cases, mutated cancer genes are potent biomarkers for responses to targeted agents. Here, to uncover new biomarkers of sensitivity and resistance to cancer therapeutics, we screened a panel of several hundred cancer cell lines--which represent much of the tissue-type and genetic diversity of human cancers--with 130 drugs under clinical and preclinical investigation. In aggregate, we found that mutated cancer genes were associated with cellular response to most currently available cancer drugs. Classic oncogene addiction paradigms were modified by additional tissue-specific or expression biomarkers, and some frequently mutated genes were associated with sensitivity to a broad range of therapeutic agents. Unexpected relationships were revealed, including the marked sensitivity of Ewing's sarcoma cells harbouring the EWS (also known as EWSR1)-FLI1 gene translocation to poly(ADP-ribose) polymerase (PARP) inhibitors. By linking drug activity to the functional complexity of cancer genomes, systematic pharmacogenomic profiling in cancer cell lines provides a powerful biomarker discovery platform to guide rational cancer therapeutic strategies.  相似文献   
375.
Flu surveillance lacking   总被引:1,自引:0,他引:1  
Butler D 《Nature》2012,483(7391):520-522
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376.
Post-mortem on mutant flu   总被引:1,自引:0,他引:1  
Butler D 《Nature》2012,484(7393):150-151
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377.
Lab flu may not aid vaccines   总被引:1,自引:0,他引:1  
Butler D 《Nature》2012,482(7384):142-143
  相似文献   
378.
Butler D 《Nature》2012,486(7402):165-166
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379.
Butler D 《Nature》2012,486(7403):301-302
  相似文献   
380.
Butler D 《Nature》2006,439(7073):124-125
  相似文献   
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