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71.
Cohen J 《Science (New York, N.Y.)》2007,318(5855):1360-1361
72.
73.
Cohen J 《Science (New York, N.Y.)》2000,289(5478):368-369
Although basic science and clinical research typically dominate at this biennial event, by far the most riveting sessions at the XIII International AIDS Conference here revolved around the thicket of issues that prevent poor people in sub-Saharan Africa--where a staggering 24.5 million people are estimated to be infected with HIV--from receiving the 14 anti-HIV treatments now used in wealthy countries. Pharmaceutical companies and donors last week loosed a flood of promises about removing barriers. Conference attendees welcomed the offers of help, but many stressed that much more will be needed. 相似文献
74.
The Holleford Crater, a circular depression in southern Ontario, is filled with Paleozoic sediments and underlain by brecciated Precambrian igneous and metamorphic rocks. The presence of coesite in two core samples of this breccia has been established by petrographic and x-ray diflraction methods. Shattered quartz in the coesite-bearing samples exhibits planar fractures. The shocked quartz is the result of great shock pressures and the association of coesite with the shocked quartz strongly suggests that Holleford Crater originated from a hypervelocity impact. 相似文献
75.
Cohen AE 《Science (New York, N.Y.)》2003,300(5623):1235-6; author reply 1235-6
76.
J Cohen 《Science (New York, N.Y.)》1991,254(5034):946-949
77.
R L Cohen 《Science (New York, N.Y.)》1972,178(63):828-835
In this review I have emphasized two basic points. First, M?ssbauer spectroscopy has been widely used as a tool for basic research in solid-state physics, chemical structure, and magnetism. Second, the technique has been applied to many analytical and materials science problems where the nature of the sample prevents the use of more traditional approaches. M?ssbauer spectroscopy research on frozen solutions, colloids, interface chemistry, and crystallographic transformations can be expected to increase rapidly in the next few years. 相似文献
78.
Cohen J 《Science (New York, N.Y.)》1993,261(5129):1678-1679
79.
Cohen J 《Science (New York, N.Y.)》2002,297(5583):927-929
80.
Cohen J 《Science (New York, N.Y.)》2000,288(5474):2159
Gulu, about 4 hours north of here by car, is in an "upcountry" region torn by armed conflict. So upcountry clinical researchers like Matthew Lukwiya, a native of the Gulu district, play a critical role--and win high praise from their colleagues. 相似文献