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The relation between domestic R&D and imports of technology is examined for 10 countries. Simple regressions revealed strong complementarity for each of the countries. Multiple regressions including GNP per capita and number of scientists and engineers were performed for the five countries with time series for all the variables. Strong complementarity was found between technology imports and domestic R&D and other variables for Japan and South Korea, weak for France, none for Germany and the US. Excluding government-financed R&D in the US resulted in a substitutive relation. Japan revealed a sharp decline in the ratio of technology payments to R&D spending; Korea is following in its steps. Complementarity appears to weaken in later stages as technology development strategies shift from dependent to imitative to autonomous or offensive technology development.  相似文献   
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Data from the 1987 National Health and Fertility Survey were used to explore trends and differentials in unwanted fertility in Mexico. Women were classified in three educational categories: illiterate or incomplete primary, complete primary or some secondary, and complete secondary or more. The four urbanization categories were: under 2500; 2500 to 19,999; 20,000 and more; and metropolitan areas. The place of primary socialization was the place of residence until age 12. Two categories of employment of household head were included, agricultural or nonagricultural. The categories for mother's employment considered employment until the union and employment between the time of union and the birth of the first child. The proportion of births that were unwanted was estimated by calculating the total fertility rate for the year before the survey and comparing it to desired family size. The "total desired family size" was 2.4 for the entire sample. In other words, nearly 37% of the total fertility rate was undesired. The greatest differentials in percentages of undesired fertility were found in educational categories. 40.7% of the total fertility rate in the least educated groups vs. 13.6% in the most educated groups was undesired. Differentials in the other categories ranged from 1.9 for a history of employment before the birth of the first child to 8.8 for agricultural or nonagricultural employment of the household head. When effects of education were controlled, the percentage of undesired fertility declined as educational level increased for all rural or urban residence categories, places of socialization, and employment groups except women who worked before the first child was born. Women with more education, urban residence, and with histories of employment had the lowest levels of undesired fertility.  相似文献   
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Beck M  Hager M  Rogers P  Miller S  Rosenberg D  Snow K 《Newsweek》1993,121(14):28-33
With Bill Clinton's new reforms only a month away, the health-care system is on the operating table--and the doctors are under the knife. Americans have a love-hate relationship with physicians: they like the care that doctors provide but hold them to blame for the nation's health-care mess. NEWSWEEK looks at how the culture of medicine may change, assesses doctors' fears--and examines the brave new world of HMOs.  相似文献   
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