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排序方式: 共有489条查询结果,搜索用时 15 毫秒
81.
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W F Price 《Journal of the American Veterinary Medical Association》1969,155(7):1267-1268
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Price DC Chan CX Yoon HS Yang EC Qiu H Weber AP Schwacke R Gross J Blouin NA Lane C Reyes-Prieto A Durnford DG Neilson JA Lang BF Burger G Steiner JM Löffelhardt W Meuser JE Posewitz MC Ball S Arias MC Henrissat B Coutinho PM Rensing SA Symeonidi A Doddapaneni H Green BR Rajah VD Boore J Bhattacharya D 《Science (New York, N.Y.)》2012,335(6070):843-847
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The technology path to deep greenhouse gas emissions cuts by 2050: the pivotal role of electricity 总被引:1,自引:0,他引:1
Williams JH DeBenedictis A Ghanadan R Mahone A Moore J Morrow WR Price S Torn MS 《Science (New York, N.Y.)》2012,335(6064):53-59
Several states and countries have adopted targets for deep reductions in greenhouse gas emissions by 2050, but there has been little physically realistic modeling of the energy and economic transformations required. We analyzed the infrastructure and technology path required to meet California's goal of an 80% reduction below 1990 levels, using detailed modeling of infrastructure stocks, resource constraints, and electricity system operability. We found that technically feasible levels of energy efficiency and decarbonized energy supply alone are not sufficient; widespread electrification of transportation and other sectors is required. Decarbonized electricity would become the dominant form of energy supply, posing challenges and opportunities for economic growth and climate policy. This transformation demands technologies that are not yet commercialized, as well as coordination of investment, technology development, and infrastructure deployment. 相似文献
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Siddiqui N Price S Hope J 《Comparative immunology, microbiology and infectious diseases》2012,35(3):219-226
Bovine tuberculosis is a disease of increasing incidence in the UK causing major economic losses and with significant impact on bovine and, potentially human health: the causative agent Mycobacterium bovis is a zoonotic pathogen. Neonatal vaccination with the attenuated M. bovis Bacille Calmette Guerin (BCG) vaccine confers a significant degree of protection in cattle, and is a widely used control strategy for human TB. The adaptive immune system is relatively immature in neonates and increased numbers of innate effector cells present in young animals and human infants may compensate for this, enabling effective immune responses to vaccination. Natural killer cells and subsets of γδ TCR+ T lymphocytes secrete high levels of interferon gamma and can interact with antigen presenting cells to promote both innate and adaptive immune responses. These cell populations may be pivotal in determining immune bias following neonatal vaccination with BCG. 相似文献
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This study was undertaken to investigate the effects of storage of stallion semen in a defined milk protein extender at 5 and 15°C under either anaerobic or aerobic conditions, with or without addition of the antibiotic gentamicin. Semen samples were collected from eight fertile stallions and stored for 96 h (day 0–4) and assessed daily for motility, velocity and membrane integrity (viability) using a CASA system. Samples for bacteriology assessment were taken on day 2 of storage. No significant (p > 0.05) differences in motility, velocity or viability were observed between treatments on days 0–2. On days 3 and 4, semen stored without gentamicin at 5°C had a significantly (p < 0.05) better semen quality compared with storage at 15°C without gentamicin, irrespective of oxygen exposure. On days 3 and 4, motility and velocity were greater in samples stored at 15°C with gentamicin, compared with the corresponding treatments without antibiotic (p < 0.05). This effect was also evident for viability on day 4. The decline in semen quality observed at 15°C most likely resulted from the effect of bacterial growth. Bacterial growth was the greatest in samples stored at 15°C without gentamicin, under both anaerobic and aerobic conditions (p < 0.05). Bacterial growth was inhibited by adding of gentamicin at 15°C, which accordingly reduced the decline in semen quality. Addition of antibiotic to samples stored at 5°C had no significant effect on any parameter analysed. In conclusion, storage at 15°C can be achieved by using an extender containing the antibiotic gentamicin. Storage at 5°C tended to maintain better semen quality irrespective of oxygen exposure, and did not necessitate an antibiotic treatment. 相似文献