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Over the last three decades fertility in Scotland, as measured by the total fertility rate (TFR), has moved from being higher than in England and Wales, to being lower. The annual number of births in Scotland has declined so that in the mid-1990s low fertility became the main driver of the overall population decline that Scotland has been experiencing since 1974. Analysis of fertility by birth order is instrumental in gaining an understanding of past and future fertility trends. Until the rise in births outside marriage in the 1980s data from registration could be used as a proxy for true birth order. However, because birth order is not collected for births outside marriage true birth order now has to be estimated. This article presents the first official estimates of true birth order for Scotland. The construction of these estimates based on a modified version of the method used for England and Wales is discussed. This article also presents analysis relating births by true birth order estimate to the population of women by parity on a cohort basis, and makes comparisons with England and Wales. 相似文献
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Genetic analysis of the mouse brain proteome 总被引:24,自引:0,他引:24
Klose J Nock C Herrmann M Stühler K Marcus K Blüggel M Krause E Schalkwyk LC Rastan S Brown SD Büssow K Himmelbauer H Lehrach H 《Nature genetics》2002,30(4):385-393
Proteome analysis is a fundamental step in systematic functional genomics. Here we have resolved 8,767 proteins from the mouse brain proteome by large-gel two-dimensional electrophoresis. We detected 1,324 polymorphic proteins from the European collaborative interspecific backcross. Of these, we mapped 665 proteins genetically and identified 466 proteins by mass spectrometry. Qualitatively polymorphic proteins, to 96%, reflect changes in conformation and/or mass. Quantitatively polymorphic proteins show a high frequency (73%) of allele-specific transmission in codominant heterozygotes. Variations in protein isoforms and protein quantity often mapped to chromosomal positions different from that of the structural gene, indicating that single proteins may act as polygenic traits. Genetic analysis of proteomes may detect the types of polymorphism that are most relevant in disease-association studies. 相似文献
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This article presents and analyses women's childbearing intentions collected in the General Household Survey (GHS). Data from the 21 surveys from 1979 to 2001 show that over that period there has been a fall in women's intended numbers of births. However the latest data (from the 1998, 2000 and 2001 surveys) show that the average number of children intended is still around two, somewhat higher than the average number of children current fertility rates suggest women will have. The questions of whether this difference can be interpreted as possible unmet need for children, whether past intentions have been good predictors of fertility, and how current intentions may be used to inform projections assumptions are discussed. In relation to the last question, fertility intentions by ethnic group are also presented. 相似文献
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Mutation in myosin heavy chain 6 causes atrial septal defect 总被引:23,自引:0,他引:23