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51.
Changelian PS Flanagan ME Ball DJ Kent CR Magnuson KS Martin WH Rizzuti BJ Sawyer PS Perry BD Brissette WH McCurdy SP Kudlacz EM Conklyn MJ Elliott EA Koslov ER Fisher MB Strelevitz TJ Yoon K Whipple DA Sun J Munchhof MJ Doty JL Casavant JM Blumenkopf TA Hines M Brown MF Lillie BM Subramanyam C Shang-Poa C Milici AJ Beckius GE Moyer JD Su C Woodworth TG Gaweco AS Beals CR Littman BH Fisher DA Smith JF Zagouras P Magna HA Saltarelli MJ Johnson KS Nelms LF Des Etages SG Hayes LS Kawabata TT 《Science (New York, N.Y.)》2003,302(5646):875-878
Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings. 相似文献
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抚仙湖北部农田区不同施肥对水稻产量、氮素吸收及利用率的影响 总被引:2,自引:0,他引:2
针对抚仙湖北部农田区的蔬菜施肥过量导致土壤养分残余量大,会对后作水稻施肥造成影响的问题,采用田间小区开展不同施肥试验研究。结果表明,砂壤土和粘壤土在施氮量为150~360 kg/hm2范围内,水稻植株氮素积累量随着施氮量的增加而提高,而增加的氮素积累量主要表现在茎叶部位;穗肥施用氮肥可提高籽粒氮素积累量。水稻氮肥吸收利用率和产量,砂壤土以施氮255 kg/hm2时最高,分别为45.1%和10594 kg/hm2;而粘壤土施氮150~360 kg/hm2之间,氮肥吸收利用率为20.9%~22.4%之间,产量为10486~10596 kg/hm2之间;当对砂壤土和粘壤土的水稻穗肥施用氮肥时,水稻氮肥吸收利用率(分别为42.8%、23.5%)和产量(分别为10445 kg/hm2、10564 kg/hm2)最高。水稻的氮素收获指数、氮肥农学利用率、氮肥生理利用率及氮肥偏生产力,均以砂壤土明显高于粘壤土,且随着施氮量的增加而显著下降。蔬菜后作水稻施氮量以150~255 kg/hm2范围为宜,氮肥分基肥50%+分蘖肥30%+穗肥20%施用 相似文献
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Ecological effects of climate fluctuations 总被引:3,自引:0,他引:3
Stenseth NC Mysterud A Ottersen G Hurrell JW Chan KS Lima M 《Science (New York, N.Y.)》2002,297(5585):1292-1296
Climate influences a variety of ecological processes. These effects operate through local weather parameters such as temperature, wind, rain, snow, and ocean currents, as well as interactions among these. In the temperate zone, local variations in weather are often coupled over large geographic areas through the transient behavior of atmospheric planetary-scale waves. These variations drive temporally and spatially averaged exchanges of heat, momentum, and water vapor that ultimately determine growth, recruitment, and migration patterns. Recently, there have been several studies of the impact of large-scale climatic forcing on ecological systems. We review how two of the best-known climate phenomena-the North Atlantic Oscillation and the El Ni?o-Southern Oscillation-affect ecological patterns and processes in both marine and terrestrial systems. 相似文献
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Chan Song Kim Jin Hur Seong Kug Eo Sang-Youel Park John Hwa Lee 《Canadian journal of veterinary research》2016,80(1):40-48
Salmonella Typhimurium ghost cells expressing K88ab, K88ac, K99, and FasA fimbriae of enterotoxigenic Escherichia coli (ETEC) in their envelopes were constructed. The genes encoding the fimbriae were individually cloned into an expression plasmid, pMMP81, carrying the asd gene, which was subsequently electroporated into the Δasd S. Typhimurium mutant. Plasmid pJHLP99, carrying the phiX174 lysis gene E, was also subsequently electroporated into the Salmonella mutant. The presence of the individual fimbriae on the ghost cells was examined by Western blot analysis. Forty BALB/c mice were equally divided into 2 groups of 20 mice each. Group A mice were intramuscularly vaccinated with a mixture of the 4 ghost cells expressing the individual fimbriae. The group B mice were inoculated with sterile phosphate-buffered saline as a control. The antigen-specific serum IgG concentrations were significantly higher in group A than in group B from week 2 until week 6 after inoculation. In addition, the antigen-specific IgA concentrations in fecal samples were significantly higher in group A than in group B at week 2 after inoculation. A large difference between the groups in the number of antigen-specific IgA-secreting cells in the small intestine was observed by immunohistochemical study. Also, the splenic lymphocyte proliferative responses were significantly greater in group A than in the control mice. These results suggest that vaccination with our Salmonella ghost cells can induce both humoral and cell-mediated immune responses and that the increased number of antigen-specific IgA-secreting cells in the small intestine may be correlated with the elevated fecal IgA immune response. 相似文献
58.
Park M 《Journal of the American Veterinary Medical Association》2007,231(2):196-7; author reply 197-8
59.
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Lee KH Cho JY Lee HJ Ma YK Kwon J Park SH Lee SH Cho JA Kim WS Park KH Moon JH 《Journal of agricultural and food chemistry》2011,59(18):10124-10128
Two novel caffeoylmalic acid methyl esters, 2-O-(trans-caffeoyl)malic acid 1-methyl ester (6) and 2-O-(trans-caffeoyl)malic acid 4-methyl ester (7), were isolated from pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peels. In addition, 5 known hydroxycinnamoylmalic acids and their methyl esters were identified: 2-O-(trans-coumaroyl)malic acid (1), 2-O-(cis-coumaroyl)malic acid (2), 2-O-(cis-coumaroyl)malic acid 1-methyl ester (3), 2-O-(trans-coumaroyl)malic acid 1-methyl ester (4), and 2-O-(trans-caffeoyl)malic acid (phaselic acid, 5). The chemical structures of these compounds were determined by spectroscopic data from ESI MS and NMR. Of all the isolated compounds, five hydroxycinnamoylmalic acids and their methyl esters (2-4, 6, 7) were identified in the pear for the first time. 相似文献