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A new human HLA class II-related locus, DM 总被引:9,自引:0,他引:9
HLA class II molecules have a crucial role in the immune response to antigens. We have isolated two new class II-like complementary DNA sequences, RING6 and RING7, which map between the HLA-DNA and -DOB loci. They are novel members of the immunoglobulin gene family which may have diverged before the duplications that gave rise to the main class II loci. The RING6 and RING7 genes seem to encode alpha- and beta-chains of a previously undiscovered class II-related protein. 相似文献
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Three isolations of a virus of the Hughes group were obtained from seabird ectoparasites, Ornithodoros (Alectorobius) maritimus, on Great Saltee Island, Ireland. The agent is closely related to Soldado virsu, originally obtained from related ticks near Trinidad, West Indies, and represents the second recorded tickborne arbovirus in Ireland. 相似文献
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Bruce W. Zoellick Charles E. Harris Brian T. Kelly Thomas P. O Farrell Thomas T. Kato Marni E. Koopman 《西北部美国博物学家》2011,62(2)
We examined the effect of oil-field development on movements and patterns of spatial use of San Joaquin kit foxes ( Vulpes macrotis mutica ) on the Naval Petroleum Reserves in California (NPRC) in the San Joaquin Valley. To do this, we compared movements and home ranges of kit foxes from June 1984 to September 1985 in areas developed for petroleum production (30% of native habitat lost to production facilities) and areas with little development (3%). Distances traveled nightly by kit foxes did not differ between levels of petroleum development or between sexes ( P > 0.2). Mean length of nightly movements during breeding (14.6 km) was longer than during pup-rearing (10.7 km) and pup-dispersal (9.4 km) periods ( P = 0.01). Mean size of home ranges was 4.6 ± 0.4 ( s ̄x ) km 2 ( n = 21) and did not differ between levels of petroleum development and sexes ( P > 0.2). Overlap of home ranges of foxes from the same social group (78 ± 4.3%) was greater than that of same-sex foxes (35 ± 7.8%) and males and females of different social groups (32 ± 8.0%, P P > 0.4). Despite extensive overlap of home ranges, kit foxes on NPRC maintained relatively exclusive core areas, particularly adjacent foxes of the same sex. Future studies should examine which levels of habitat conversion impact spatial use of kit foxes. 相似文献
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Gregory D. Warrick Howard O. Clark Jr. Patrick A. Kelly Daniel F. Williams Brian L. Cypher 《西北部美国博物学家》2011,67(2)
Although the current range of the endangered San Joaquin kit fox ( Vulpes macrotis mutica ) borders large areas of farmland, the ecology of this species rarely has been studied within an agricultural setting. In central California, we examined habitat use, prey availability, and diet of radio-collared kit foxes inhabiting an aqueduct right-of-way (ROW) bordered by farmland. During both years of study (1998–1999), nocturnal locations of foxes occurred more often than expected (based on habitat availability) in the ROW and less often than expected within annual crops. Orchards were used disproportionately more than their availability during 1998 and were used in proportion to availability during 1999. Kit foxes traveled up to 1.1 km into annual crops and up to 1.5 km into orchards. Among diurnal locations (den sites) of foxes, 98% were within the ROW. Live-trapping revealed higher densities and greater diversity of rodents along the ROW than within farmland. Remains of murid rodents were found in 79% of kit fox scats. Our findings indicated that kit foxes ranged into orchards and annual croplands at night, but almost never occupied these areas during the day. The lack of den sites and low prey availability within farmland probably limited the ability of kit foxes to exploit and occupy these areas. Providing artificial den sites within croplands (especially within orchards) and along canals may increase use of farmland by kit foxes and facilitate their movement between isolated patches of natural lands. 相似文献
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Lincoln P. Brower Kelly Sims Dunford James C. Dunford Amy L. Knight Jaret Daniels 《Journal of Natural History》2018,52(31-32):2025-2046
Long-term springtime counts of immature and adult monarch butterflies and their Asclepias humistrata host plants in north-central Florida reveal a close relationship between the milkweed’s phenology and the butterfly’s spring remigration from Mexico. Remigrant adults arrive after most frosts occur and as the milkweeds are flourishing but before the plants begin to senesce. The peak of adult arrival is during the first few days in April; the eggs that are laid during this peak develop through April, leading to a second peak in adult abundance in early May. These newly emerged adults continue the migration northward. In addition to assessing the phenology of annual events, our long-term survey, with regular monitoring from 1994–2017, has enabled us to evaluate long-term trends. Both adults and immatures have declined in abundance from 1985 to 2017; since 2005, both have declined by around 80%. This decline has occurred concurrently with the decline in the number of monarchs at their Mexican overwintering sites. 相似文献
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