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排序方式： 共有573条查询结果，搜索用时 15 毫秒
31.
Jha P Mills A Hanson K Kumaranayake L Conteh L Kurowski C Nguyen SN Cruz VO Ranson K Vaz LM Yu S Morton O Sachs JD 《Science (New York, N.Y.)》2002,295(5562):2036-2039
We analyzed the technical basis for a major global program to reduce disease among the poor. Effective interventions exist against the few diseases which most account for excess mortality among the poor. Achieving high coverage of effective interventions requires a well-functioning health system, as well as overcoming a set of financial and nonfinancial constraints. The annual incremental cost would be between $40 billion and $52 billion by 2015 in 83 low-income and sub-Saharan African countries. Such a program is feasible and would avoid millions of child, maternal, and adult deaths annually in poor countries. 相似文献
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Hydrocortisone is necessary for the formation of rough endoplasmic reticulum in mammary alveolar epithelial cells. This membrane system is required for the synthesis of the milk protein, casein, but it is not required for the synthesis of a nonmilk protein fraction. 相似文献
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Ravishankara AR Turnipseed AA Jensen NR Barone S Mills M Howard CJ Solomon S 《Science (New York, N.Y.)》1994,263(5143):71-75
Hydrofluorocarbons, many of which contain a CF(3) group, are one of the major substitutes for the chlorofluorocarbons and halons that are being phased out because they contribute to stratospheric ozone depletion. It is critical to ensure that CF(3) groups do not cause significant ozone depletion. The rate coefficients for the key reactions that determine the efficiency of the CF(3) radical as a catalyst for ozone loss in the stratosphere have been measured and used in a model to calculate the possible depletion of ozone. From these results, it is concluded that the ozone depletion potentials related to the presence of the CF(3) group in hydrofluorocarbons are negligibly small. 相似文献
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Periodic slow earthquakes from the Cascadia subduction zone 总被引：1，自引：0，他引：1
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Mills TJ 《Science (New York, N.Y.)》1958,127(3295):431-435
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McBride JM Segmuller BE Hollingsworth MD Mills DE Weber BA 《Science (New York, N.Y.)》1986,234(4778):830-835
Organic single crystals provide an ideal model for studying the factors that influence chemical processes in structured media. Reaction trajectories are well defined and reveal the influence of spontaneous mechanical stresses equivalent to tens of thousands of atmospheres. Analysis of molecular and crystal structures helps to explain both local mechanical properties, which influence reactions, and bulk properties such as melting point, compressibility, and surface energy. 相似文献