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125-I-IgG binding activities were observed with 15 (17%) of 90 S. intermedius isolates from dogs and 39 (95%) of 41 S. hyicus isolates from pigs. Binding activities were not detected with S. hyicus isolates from cows. The IgG binding proteins of 2 S. intermedius, 2 S. hyicus, and protein A from S. aureus Cowan I were isolated from their cell surfaces. The proteins precipitated with IgG preparations from human, rabbit, pig, dog and horse, but not with IgG from cow, mouse and chicken. This indicated that these IgG binding proteins could be classified as type I receptors. In addition, the isolated proteins from all 3 staphylococcal species precipitated with polyclonal chicken anti-protein A antiserum. SDS-PAGE, Western blotting and gel isoelectric focussing of the proteins revealed numerous bands in the 42,000 D range and acid isoelectric points. The isoelectric point of the isolated proteins from both S. intermedius cultures was slightly more acidic than those from S. hyicus and S. aureus. The present results indicate a close functional and antigenic similarity, if not identity, between IgG binding proteins of S. intermedius and S. hyicus, and protein A of S. aureus.  相似文献   
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Osteoma of the zygomatic arch in a cat   总被引:4,自引:0,他引:4  
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Behavior and phylogeny: constriction in ancient and modern snakes   总被引:2,自引:0,他引:2  
Comparative analyses of behavior have an underappreciated potential for revealing the role of ethoecological factors in the origins of higher taxa. Twenty-seven species (13 genera) in the advanced family Colubridae exhibited 19 patterns of coil application; one or two patterns were usually consistent within a genus. Forty-eight species (26 genera) in the primitive families Acrochordidae, Aniliidae, Boidae, and Xenopeltidae usually used a single pattern, despite differences in age, size, shape, habitat, and diet. This implies the shared retention of an action pattern used by their common ancestor no later than the early Paleocene. Constriction must have been used as a prey-killing tactic very early in the history of snakes and might have been a behavioral "key innovation" in the evolution of their unusual jaw mechanism.  相似文献   
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Stink bugs (Hemiptera: Pentatomidae) are ubiquitous, cryptic, phytophagous pests that are found in many crops. In agroecosystems, individuals disperse from adjacent noncrop hosts and tend to aggregate or cluster within fields. In this study, we characterized the distribution of Euschistus servus (Say) and Euschistus tristigmus (Say) (Hemiptera: Pentatomidae) over 2 yr at three southeastern United States farmscapes. Stink bugs were captured in pheromone-baited traps, and Spatial Analysis by Distance Indices (SADIE) used to identify the location of significant aggregations by habitat type and season. Euschistus servus adults were more likely to be captured in pecan orchards, cotton, other crops, or unmanaged habitats than in woodland habitats. Significant aggregations of E. servus were detected in a variety of habitats including pecan, corn, cotton, peanut, and tobacco, as well as fallow and hay fields, pastures, and hedgerows. Fewer adult E. tristigmus were captured than E. servus adults, and E. tristigmus adults were typically trapped and aggregated in woodland habitats. The resulting data provide an important understanding regarding the seasonal movement and relative abundance levels of stink bug populations, which are critical to the development of integrated pest management strategies.  相似文献   
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Some of the current directions of scientific research on electrically conducting organic solids are reviewed. Both molecular charge transfer salts and polymers are included, with emphasis on the present level of understanding of the novel solid-state properties of these materials in terms of their chemistry and structure. For the charge transfer salts the various types of metal-to-insulator phase transitions which dominate the properties of most of these materials are discussed. Also described are the superconducting and magnetic states which have been found recently. In the case of the polymers the chemistry and physics of the conduction mechanism is examined and contrasted with that of their classical inorganic counterparts.  相似文献   
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