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31.
Detection of an antigen associated with acute leukemia 总被引:10,自引:0,他引:10
Antiserums to a purified cell membrane component from a Burkitt's lymphoma tissue culture cell line were produced in rabbits. These antiserums were cytotoxic to peripheral white blood cells from 8 of 15 patients with acute leukemia and 5 of 41 relatives, but not to peripheral white blood cells from leukemia patients in clinical remission or from normal individuals. These antiserums appear to be detecting an acute leukemia associated antigen or antigens. 相似文献
32.
A glacial varve chronology from New England spanning the 4000-year period from 17,500 to 13,500 calendar years before the present was analyzed for evidence of climate variability during the late Pleistocene. The chronology shows a distinct interannual (3 to 5 years) band of enhanced variability suggestive of El Nino-Southern Oscillation (ENSO) teleconnections into North America during the late Pleistocene, when the Laurentide ice sheet was near its maximum extent and climatic boundary conditions were different than those of today. This interannual variability largely disappears by the young end of the 4000-year chronology, with only the highest frequency components (roughly 3-year period) persisting. This record provides evidence of ENSO-like climate variability during near-peak glacial conditions. 相似文献
33.
Mann ME 《Science (New York, N.Y.)》2000,289(5477):253-254
The climate changes believed to have occurred before this century have remained enigmatic, hampering our understanding of today's climatic changes. Reseachers trying to assess the human influence on the warming of the past century have commonly used complex ocean atmosphere models, but these models have their drawbacks. In his Perspective, Mann discusses a research article by Crowley, who has used a simple model driven by the most important natural and human-induced climate forcings to simulate climatic change over the last millennium. Comparing the model results with observations, Crowley makes what may be the most compelling case to date for the assertion that anthropogenic greenhouse gas increases are behind the dramatic continued warming of the globe. 相似文献
34.
The absorption of ultra-violet light by three bacteriophages C13, C16 and C36, prepared with a strain of Escherichia communior has been determined. Each bacteriophage preparation showed a characteristic absorption curve, when the wave-length was plotted against the photographic density. Crude bacteriophage preparations absorbed more light than one such preparation obtained in a purer state, but the wavelength of maximum absorption remained the same. 相似文献
35.
Mann CC 《Science (New York, N.Y.)》2002,297(5583):921
36.
Mann CC 《Science (New York, N.Y.)》2008,321(5893):1148-1152
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