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We report on a case of trisomy 8 mosaicism detected prenatally in a single clone of amniotic fluid culture, and confirmed on fetal blood and on peripheral lymphocytes after birth. A follow-up was performed over 3 years, showing a clinically normal female with cognitive, neuropsychological, and linguistic development in a normal range.  相似文献   
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Since the end of the 1970s, the southern European countries have shown an exceptional reduction in fertility rate. From the highest levels among the developed nations, these countries dropped beneath the substitution rate level: in Greece there is an average of about 1.5 children per woman, and Italy (starting three to four years ago), with 1.3 children per woman, is now the country with the lowest fecundity rate in the world. Land-use planning in southern European small islands therefore requires substantial revision. In the areas where western civilization began, which are highly populated and have a long history, cultural and ethnic aspects of tradition are fundamental to environmental management and to the defense of historical heritage. They also place a strong value on sustaining tourism, the most relevant economic activity, that allows them to survive and maintain a high welfare level. For some decades they have had populations with a marked presence of young people and high emigration rates, but now they are fast becoming dominated by the elderly and must prepare for a period of fast reduction in youth of the workforce, while the peripheral areas of Asia and Africa are entering a sudden demographic growth phase. The demographic structure has also been deeply altered both by previous migrations and by random variations, as usually happens in all small communities. Social services for younger and older people have had to be adapted rapidly, reorganizing high-school management, hospital and health-care structures, in-house assistance, and so on. There is a need to rethink the job market and favor the immigration of highly specialized workers, which is a necessity for technical evolution. Sustainable development is constrained nowadays not only by the scarcity of natural resources, but also by the quality and quantity of human resources. Proper policies for population and land-use planning are highly correlated factors; they have to be considered with respect of these new, rapid demographic changes.  相似文献   
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ABSTRACT: An econometric demand function is estimated for residential water use in Metropolitan Manila. Regression results using annual time series data from 1970 to 1981 show that residential water consumption responds to changes in economic variables. Residential demand showed an income (household) elasticity of 0.542 and a combined price elasticity of -0.287. Implications for planning and management are discussed.  相似文献   
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