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81.
82.
Endotoxin, or lipopolysaccharide (LPS), is responsible for pathogenesis of infections induced by Gram-negative bacteria, such as E. coli. The cellular response to LPS is modulated by interactions among LPS, LPS-binding protein (LBP) and CD14. Accumulated evidence shows that the soluble form of CD14 (sCD14) competes with membrane-bound CD14 (mCD14) for LPS and plays a pivotal role in regulating bacterial infection and septic shock caused by Gram-negative bacteria. Recombinant bovine sCD14 (rbosCD14) was produced by transfected insect sf/9 cells and its biological function was evaluated in mice. Eighty-one 8-week old BALB/cj female mice were randomly assigned to two groups, and injected intraperitoneally with either LPS (8 microg/g of body weight, n = 41) or LPS plus rbosCD14 (6.8 microg/g of body weight, n = 40). Survival rate at 24 h after injection for mice injected with either LPS or LPS plus rbosCD14 was 30 and 72%, respectively (P < 0.01). At 48 h survival rate was 7 and 37%, respectively (P < 0.01). To investigate the protective effect of rbosCD14 on experimentally induced mastitis in mice, two abdominal contralateral mammary glands of 7 lactating BALB/cj mice were injected through the teat canal with 10-20 colony-forming units (CFU) of Escherichia coli. One gland simultaneously received rbosCD14 (6 microg) and the other saline. At 24 h after challenge, glands that received rbosCD14 had less swelling and hemorrhaging, significantly lower bacterial counts (P < 0.05) and lower concentrations of TNF-alpha (P < 0.05). Results indicate that rbosCD14 is biologically functional and reduces mortality in mice from endotoxin shock and severity of intramammary infection by E. coli.  相似文献   
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Every year, the Student Debates Subcommittee (SDS) of the Student Affairs Committee (SAC) for the annual Entomological Society of America (ESA) meeting organizes the Student Debates. This year, the SAC selected topics based on their synergistic effect or ability to ignite exponential positive change when addressed as a whole. For the 2019 Student Debates, the SAC SDS identified these topic areas for teams to debate and unbiased introduction speakers to address: 1) how to better communicate science to engage the public, particularly in the area of integrated pest management (IPM), 2) the influential impacts of climate change on agriculturally and medically relevant insect pests, and 3) sustainable agriculture techniques that promote the use of IPM to promote food security. Three unbiased introduction speakers gave a foundation for our audience to understand each debate topic, while each of six debate teams provided a strong case to support their stance or perspective on a topic. Debate teams submitted for a competitive spot for the annual ESA Student Debates and trained for the better part of a year to showcase their talents in presenting logical arguments for a particular topic. Both the debate teams and unbiased introduction speakers provided their insight toward a better understanding of the complexities of each topic and established a foundation to delve further into the topics of science advocacy and communication, climate change, and the many facets of integrated pest management.  相似文献   
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Ohne Zusammenfassung Mit 8 Abbildungen.  相似文献   
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Rundschau     
Ohne Zusammenfassung  相似文献   
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A toy Australian shepherd dog was referred for bile peritonitis following excision of a biliary mucocele. Subsequent delayed gastric emptying was refractory to prokinetic therapy but responded to injection of botulinum toxin A into the muscularis layer of the pylorus; a novel therapy for delayed gastric emptying in dogs.  相似文献   
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Type III secreted "effector" proteins of bacterial pathogens play central roles in virulence, yet are notoriously difficult to identify. We used an in vivo genetic screen to identify 13 effectors secreted by the type III apparatus (called Hrp, for "hypersensitive response and pathogenicity") of the plant pathogen Pseudomonas syringae. Although sharing little overall homology, the amino-terminal regions of these effectors had strikingly similar amino acid compositions. This feature facilitated the bioinformatic prediction of 38 P. syringae effectors, including 15 previously unknown proteins. The secretion of two of these putative effectors was shown to be type III--dependent. Effectors showed high interstrain variation, supporting a role for some effectors in adaptation to different hosts.  相似文献   
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