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81.
Watson A 《Science (New York, N.Y.)》2000,290(5495):1287a-1288a
With calls to tie the European Space Agency (ESA) more closely to the business and security sectors (see sidebar), space scientists hope David Southwood, who will take over next May as ESA's science director, can nurture the agency's research with the skill he showed transforming its earth sciences division. Experts say he's up to the task. 相似文献
82.
The human genome project: past, present, and future 总被引:18,自引:0,他引:18
J D Watson 《Science (New York, N.Y.)》1990,248(4951):44-49
This article presents a short discussion of the development of the human genome program in the United States, a summary of the current status of the organization and administration of the National Institutes of Health component of the program, and some prospects for the future directions of the program and the applications of genome information. 相似文献
83.
Evidence for homologous actions of pro-opiocortin products 总被引:2,自引:0,他引:2
alpha-Melanocyte-stimulating hormone (alpha-MSH), a modified fragment of adrenocorticotropic hormone, derives from the same biosynthetic route as beta-endorphin and is stored by the same arcuate neurons. Microinjection of alpha-melanocyte-stimulating hormone and several related peptides into the periaqueductal gray matter significantly reduced responsiveness to pain and had a behavioral profile similar to that produced by beta-endorphin. 相似文献
84.
85.
Potamotrygon spp.: elasmobranchs with low urea content 总被引:1,自引:0,他引:1
All previously reported species of Chondrichthyes, from both marine and fresh water, have contained urea at concentrations ranging from about 300 to 1300 milligrams of urea nitrogen per 100 milliliters of fluid. Body fluids from two species of Potamotrygon, permanent residents of the Amazon basin, contained only 2 to 3 milligrams of urea nitrogen per 100 milliliters. Although they have abandoned the retention of urea exhibited by other chondrichthyans, the extent to which they have lost the mechanisms of retaining and tolerating urea in a hypertonic medium has not been determined. 相似文献
86.
Watson A 《Science (New York, N.Y.)》2002,295(5563):2194-2195
87.
Watson WW 《Science (New York, N.Y.)》1941,93(2420):473-474
88.
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90.
Watson A 《Science (New York, N.Y.)》2000,289(5481):850-854
Forensic scientists are equipping police investigators with powerful tools for collecting and analyzing evidence. But as detection techniques become increasingly sensitive, the problem of sifting the wheat from the chaff at a crime scene mushrooms, guaranteeing a role for the human investigator despite all the gadgetry. Moreover, some developments are also raising civil liberties concerns. 相似文献