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101.
102.
Kelly WG 《Science (New York, N.Y.)》2008,319(5860):158-159
103.
Leifer R Juzdan ZR Kelly WR Fassett JD Eberhardt KR 《Science (New York, N.Y.)》1987,238(4826):512-514
The nuclear reactor from the Soviet radar reconnaissance satellite, Cosmos-1402, reentered the earth's atmosphere on 7 February 1983 and disintegrated over the South Atlantic Ocean. The reactor was powered by approximately 50 kilograms of uranium-235 ((235)U). In an effort to determine the fate of the reactor core, a series of aerosol samples were collected at altitudes between 27 and 36 kilometers in the Northern Hemisphere approximately 1.1 years later by high-altitude balloons. At an altitude of 36 kilometers a 53 +/- 20 percent excess in the (235)U concentration was measured. The total excess of (235)U in the stratosphere was calculated to be 44 +/- 15 kilograms. 相似文献
104.
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
105.
Kelly MP 《Science (New York, N.Y.)》1988,240(4856):1208-1209
106.
Sreedharan J Blair IP Tripathi VB Hu X Vance C Rogelj B Ackerley S Durnall JC Williams KL Buratti E Baralle F de Belleroche J Mitchell JD Leigh PN Al-Chalabi A Miller CC Nicholson G Shaw CE 《Science (New York, N.Y.)》2008,319(5870):1668-1672
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disorder characterized pathologically by ubiquitinated TAR DNA binding protein (TDP-43) inclusions. The function of TDP-43 in the nervous system is uncertain, and a mechanistic role in neurodegeneration remains speculative. We identified neighboring mutations in a highly conserved region of TARDBP in sporadic and familial ALS cases. TARDBPM337V segregated with disease within one kindred and a genome-wide scan confirmed that linkage was restricted to chromosome 1p36, which contains the TARDBP locus. Mutant forms of TDP-43 fragmented in vitro more readily than wild type and, in vivo, caused neural apoptosis and developmental delay in the chick embryo. Our evidence suggests a pathophysiological link between TDP-43 and ALS. 相似文献
107.
108.
Seiff A Kirk DB Young RE Sommer SC Blanchard RC Findlay JT Kelly GM 《Science (New York, N.Y.)》1979,205(4401):46-49
The altitude profiles of temperature and pressure measured during the descent of the four Pioneer Venus probes show small contrast below the clouds but significant differences within the clouds at altitudes from 45 to 61 kilometers. At 60 kilometers, the probe which entered at 59.3 degrees north latitude sensed temperatures 25 K below those of the lower latitude probes, and a sizable difference persisted down to and slightly below the cloud base. It also sensed pressure below those of the other probes by as much as 49 millibars at a mean pressure of 200 millibars. The measured pressure differences are consistent with cyclostrophic balance of zonal winds ranging from 130 +/- 20 meters per second at 60 kilometers to 60 +/- 17 meters per second at 40 kilometers, with evidence in addition of a nonaxisymmetric component of the winds. The clouds were found to be 10 to 20 K warmer than the extended profiles of the lower atmosphere, and the middle cloud is convectively unstable. Both phenomena are attributed to the absorption of thermal radiation from below. Above the clouds, in the lower stratosphere, the lapse rate decreases abruptly to 3.5 K per kilometer, and a superimposed wave is evident. At 100 kilometers, the temperature is minimum, with a mean value of about 170 K. 相似文献
109.
Wood-based mulches are used in avocado production and are being tested on Fraser fir for reduction of Phytophthora root rot, caused by Phytophthora cinnamomi. Research with avocado has suggested a role of microbial cellulase enzymes in pathogen suppression through effects on the cellulosic cell walls of Phytophthora. This work was conducted to determine whether cellulase activity could account for disease suppression in mulch systems. A standard curve was developed to correlate cellulase activity in mulches with concentrations of a cellulase product. Based on this curve, cellulase activity in mulch samples was equivalent to a cellulase enzyme concentration of 25 U ml(-1) or greater of product. Sustained exposure of P. cinnamomi to cellulase at 10 to 50 U ml(-1) significantly reduced sporangia production, but biomass was only reduced with concentrations over 100 U ml(-1). In a lupine bioassay, cellulase was applied to infested soil at 100 or 1,000 U ml(-1) with three timings. Cellulase activity diminished by 47% between 1 and 15 days after application. Cellulase applied at 100 U ml(-1) 2 weeks before planting yielded activity of 20.08 μmol glucose equivalents per gram of soil water (GE g(-1) aq) at planting, a level equivalent to mulch samples. Cellulase activity at planting ranged from 3.35 to 48.67 μmol GE g(-1) aq, but no treatment significantly affected disease progress. Based on in vitro assays, cellulase activity in mulch was sufficient to impair sporangia production of P. cinnamomi, but not always sufficient to impact vegetative biomass. 相似文献
110.
Spatial variation of soil enzyme activities and microbial functional diversity in temperate alley cropping systems 总被引:1,自引:0,他引:1
Nancy W. Mungai Peter P. Motavalli Robert J. Kremer Kelly A. Nelson 《Biology and Fertility of Soils》2005,42(2):129-136
Spatially dependent patterns in microbial properties may exist in temperate alley cropping systems due to differences in litter quality and microclimate in areas under trees compared to those in the alleys. The effect of tree row location was evaluated for its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at the tree row and at the middle of the alley at two sites: a 21-year-old pecan (Carya illinoinensis)/bluegrass (Poa trivials) intercrop (Pecan site) and a 12-year-old silver maple (Acer saccharinum)/soybean (Glycine max)–maize (Zea mays) rotation (Maple site). Sampling was done in fall 2001 and summer 2002. β-Glucosidase activities, Biolog patterns expressed as average well color (AWC), substrate richness, and Shannon diversity index, and total Kjeldahl nitrogen (TKN) were significantly higher (P<0.05) in the tree row than at the middle of the alley for surface soils at the Pecan site. Fluorescein diacetate (FDA) hydrolytic activity was also higher at the tree row for soils sampled in the fall, but did not differ significantly for soils sampled in the summer. At the Maple site, AWC and substrate richness were significantly higher at the tree row for soils sampled in 2001. Soil volumetric water content and temperature were generally lower in the tree row at the Maple site. The results of this study suggest that functionally different microbial populations may be present under pecan trees compared to cropped alleys which may promote disparities in nutrient availability necessitating differential long-term nutrient management in such alley cropping systems. 相似文献