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81.
Among datasets available for fertility research in England and Wales, the Office for National Statistics (ONS) Longitudinal Study (LS) is unique in its construction and scale. The large number of individuals who are part of the study means that it is an important dataset for estimating fertility trends in England and Wales by age and parity. This article uses the LS to estimate age-specific fertility rates (ASFRs) for England and Wales between 1991 and 2001. This necessitates great care to ensure that the exposure to risk of birth for female LS members is fully understood. To achieve this, two forms of residential history are defined - consistent cases where the residential information for the LS member is potentially complete for the whole decade and inconsistent cases where there is certainly some form of incompleteness in the residence information. By considering 'all consistent cases', that is both the continuously resident plus those who are not continuously resident but appear to have a complete residential history, we obtain ASFRs which are slightly lower than official statistics figures, but closer to these official figures than ASFRs produced when restricting the sample to LS members who remain continuously resident between 1991 and 2001. The fertility of those consistent cases who are not continuously resident is substantially higher than the rates of continuously resident cases. 相似文献
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This article examines changes between 1984 and 2007 in the demographic and socio-economic circumstances of British men and women in mid-life. Changing living arrangements in mid-life reflect historical changes in the occurrence and timing of life events such as marriage and parenthood, as well as increased longevity. In order to place mid-life in this wider demographic context, the article first reviews changes over time in kin availability across the adult life course using the British Household Panel Survey (2001) and Understanding Society (2009). The article goes on to use data from the General Household Survey (1984-2007) to document shifts over time in living arrangements for those aged 20- 79. In the final part of the article we focus specifically on those aged between 45 and 64 and examine how their characteristics in terms of marital status, educational attainment, activity status and housing tenure have changed over the past quarter century. 相似文献
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Zusammenfassung Beim HechtEsox lucius L. liess sich ein Lymphosarkom durch zellfreie Filtrate übertragen und damit die Virus-Aetiologie nachweisen. 相似文献
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A major aim in immunology has been to understand how the immune system evokes characteristic responses to infection, foreign tissue grafts and tumours. The current view of immunoregulation is based mainly on studies of lymphocyte subsets, either in vitro or by adoptive transfer to irradiated recipients. Many reagents are available for defining T-cell subsets, but only recently have there been helper T-cell-specific antibodies against the mouse equivalent of the Leu3/T4 (man) and W3/25 (rat) antigens. It is clear that monoclonal antibodies will eventually replace antilymphocyte globulin for immunosuppression in organ grafting, but although there has been some clinical success, most monoclonal reagents cause only transient reductions in their target cells in vivo. This uncertainty in the potency of monoclonal antibodies has led some workers to consider them as targeting agents for such highly cytotoxic drugs as ricin A (ref. 21). We show here that unmodified monoclonal antibodies can be extremely effective at depleting cells in vivo and can be used for the selective manipulation of different aspects of the immune response. 相似文献
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