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排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
J. H. Heckman H. G. Zuckerman C. H. Metzger B. A. Brown E. R. Bennett W. B. Ward C. L. Fitch O. H. Elmer Jhon S. Gardner Julan C. Miller Frank W. Hussey E. L. Newdick Ralph W. Donaldson Lionel Harris H. O. Werner Wm. H. Martin E. V. Hardenburg T. E. Odland Robert Schmidt Geo E. Prince Brooks D. Drain Harold L. Bailey G. S. Ralston Chase D. Gaines J. G. Milward John Tucker 《American Journal of Potato Research》1935,12(6):158-170
2.
Production of ex vivo lipopolysaccharide-induced tumor necrosis factor-α, interleukin-1β, and interleukin-6 is suppressed by trans-resveratrol in a concentration-dependent manner 下载免费PDF全文
Jean-Francois Marier Keguan Chen Peter Prince George Scott Jerome R.E. del Castillo Pascal Vachon 《Canadian journal of veterinary research》2005,69(2):151-154
Trans-resveratrol is a biologically active compound present in certain foods that has anti-inflammatory and anticancer properties. These beneficial effects are derived from both the immune system and cytokines. The purpose of this study was to determine the immunomodulatory effect of trans-resveratrol on the ex vivo production of inflammatory and anti-inflammatory cytokines stimulated by lipopolysaccharides (LPS). Trans-resveratrol (0, 0.01, 0.1, 1, and 10 microM) was added to blood samples from male Sprague-Dawley rats (n = 6) along with 100 U of LPS (Escherichia coli serotype, 055B5). The samples were then incubated for 4 h at 37 degrees C and centrifuged. Finally, concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 in the plasma were analyzed using an enzyme-linked immunosorbent assay (ELISA). The production of inflammatory (TNF-alpha and IL-1beta) and anti-inflammatory (IL-6) cytokines was suppressed by trans-resveratrol in a concentration-dependent manner. These results support the hypothesis that the immunomodulatory effect of trans-resveratrol plays an important role in disease conditions that involve an overproduction of inflammatory cytokines. 相似文献
3.
Development and evaluation of a rapid absorbed enzyme immunoassay test for the diagnosis of Johne''s disease in cattle 总被引:8,自引:0,他引:8
An absorbed enzyme immunoassay (EIA) test for Johne's disease in cattle was developed in which absorption of cross-reacting antibodies occurred as a rapid reaction in solution rather than overnight with whole organisms and a subsequent centrifugation step. Total test time was reduced to less than 2 h with a minimum of manipulations. The test was evaluated in cattle herds from Johne's disease-endemic and Johne's disease-free regions of Australia. Specificity was 99.8%. Calculations of sensitivity were affected by the history of the herd under test. However, the EIA detected in excess of 80% of animals before onset of clinical disease and 65% of faecal shedders were EIA positive on, or before, first detection of Mycobacterium paratuberculosis in their faeces. The test should aid epidemiological studies and be a useful tool in the management and control of Johne's disease. 相似文献
4.
Serum hepatitis antigen (SH): rapid detection by high voltage immunoelectroosmophoresis 总被引:30,自引:0,他引:30
An immunoelectroosmophoretic technique for rapid detection of the antigen (SH) associated with the serum hepatitis virus has been devised. The technique maintains the specificity characteristic of the Ouchterlony gel-diffusion method, yet detects in 1 to 2 hours one-tenth the amount of antigen required for gel diffusion. The test has immediate application to blood-banking practice since it permits the screening of such labile products as platelets and fresh whole blood, and the detection of antigen in additional serums negative by the Ouchterlony technique. 相似文献
5.
Measurements of electrical conductivity at high pressure and temperature were taken on the lower mantle phase magnesiowustite with varying Fe3+ content. Although previous measurements at atmospheric pressure suggest Fe2+-Fe3+ hopping (small polaron) as the dominant conductivity mechanism, the present experiments show a change in charge transport mechanism with temperature. The lower temperature measurements are consistent with small polaron conduction, but at higher temperatures, which are more applicable to the lower mantle, a large polaron mechanism is suggested. Because these mechanisms have different temperature and compositional dependencies, this transition has important implications for extrapolation to mantle conditions. 相似文献
6.
Prince AM 《Science (New York, N.Y.)》2008,321(5896):1631-4; author reply 1631-4
7.
DH Lowndes DB Geohegan AA Puretzky DP Norton CM Rouleau 《Science (New York, N.Y.)》1996,273(5277):898-903
Pulsed laser deposition (PLD) is a conceptually and experimentally simple yet highly versatile tool for thin-film and multilayer research. Its advantages for the film growth of oxides and other chemically complex materials include stoichiometric transfer, growth from an energetic beam, reactive deposition, and inherent simplicity for the growth of multilayered structures. With the use of PLD, artificially layered materials and metastable phases have been created and their properties varied by control of the layer thicknesses. In situ monitoring techniques have provided information about the role of energetic species in the formation of ultrahard phases and in the doping of semiconductors. Cluster-assembled nanocrystalline and composite films offer opportunities to control and produce new combinations of properties with PLD. 相似文献
8.
Monitoring primary production from Earth observing satellites 总被引:1,自引:0,他引:1
Satellite remotely sensed observations provide a unique capacity to monitor biospheric activity at regional and global scales. Spectral vegetation indices from these observations capture the heterogeneity of growth patterns across the Earth's surface including the significant decline in vegetation activity above 50°N latitude. Conversion of these observations to meaningful assessments of vegetation growth, particularly changes within and between years, requires more than a simple linear transform between the spectral vegetation index and forest production. Although satellite observations of vegetation indices are essential, appropriate environmental variables and models are also necessary. The approach is illustrated by a study of the southern Boreal forest in northern Minnesota. A conceptual and methodological framework for monitoring primary production from remotely sensed observations alone is proposed and results of its application in the Global Production Efficiency Model (GLO-PEM) for global boreal forests are discussed. 相似文献
9.
Effects of additional feed during late gestation on reproductive performance of sows: a cooperative study 总被引:4,自引:0,他引:4
G L Cromwell D D Hall A J Clawson G E Combs D A Knabe C V Maxwell P R Noland D E Orr T J Prince 《Journal of animal science》1989,67(1):3-14
A cooperative research study involving 1,080 litters was conducted at eight stations to determine the effects of additional feed during the last 23 d of gestation on reproductive performance of sows and on preweaning performance of their pigs. Primiparous and multiparous sows were fed fortified corn- or sorghum-soybean meal diets (14% crude protein). Control sows received 1.82 kg/d from March through November and 2.27 kg/d from December through February. Treated sows were fed an additional 1.36 kg of feed/d from d 90 of gestation to farrowing. Sows were allowed to consume the same diet ad libitum during a 21-d lactation. Additional feed in late gestation resulted in greater (P less than .001) sow weight gain from d 90 to d 110 of gestation (16.8 vs 9.0 kg) and greater (P less than .001) parturition-lactation weight loss (21.3 vs 16.4 kg). Total weight gain from breeding to 21 d of lactation favored sows that received extra feed (27.5 vs 22.7 kg; P less than .001). Sows receiving extra feed had more live pigs at farrowing (10.05 vs 9.71, P = .06) and at 21 d postpartum (8.35 vs 8.06, P = .09), and the pigs were heavier at birth (1.48 vs 1.44 kg, P = .003) and at 21 d (5.37 vs 5.20 kg, P = .006). Lactation feed intake and number of days from weaning to estrus were not affected by treatment. The results indicate that additional feed in late gestation improves reproductive performance in sows. In this study, the cost of an additional 31 kg of feed/sow was more than offset by the value of the additional sow weight gain (approximately 5 kg), the additional .3 of a pig/litter at weaning and the additional 2.6 kg of total litter weaning weight. 相似文献
10.
The future demand for and potential shortages of food-supply veterinarians have been the subject of much concern. Using the Delphi forecasting method in a three-phase Web-based survey process, a panel of experts identified the trends and issues shaping the demand for and supply of academic food-animal veterinarians, then forecasted the likely future demand and shortages of food-supply veterinarians employed in academic institutions in the United States and Canada through 2016. The results indicate that there will be increasing future demand and persistent shortages of academic food-supply veterinarians unless current trends are countered with targeted, strategic action. The Delphi panel also evaluated the effectiveness of several strategies for reversing current trends and increasing the number of food-supply veterinarians entering into academic careers. Academic food-supply veterinarians are a key link in the system that produces food-supply veterinarians for all sectors (private practice, government service, etc.); shortages in the academic sector will amplify shortages wherever food-supply veterinarians are needed. Even fairly small shortages have significant public-health, food-safety, animal-welfare, and bio-security implications. Recent events demonstrate that in an increasingly interconnected global economic food supply system, national economies and public health are at risk unless an adequate supply of appropriately trained food-supply veterinarians is available to counter a wide variety of threats ranging from animal and zoonotic diseases to bioterrorism. 相似文献