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Reproductive carrier screening started in some countries in the 1970s for hemoglobinopathies and Tay-Sachs disease. Cystic fibrosis carrier screening became possible in the late 1980s and with technical advances, screening of an ever increasing number of genes has become possible. The goal of carrier screening is to inform people about their risk of having children with autosomal recessive and X-linked recessive disorders, to allow for informed decision making about reproductive options. The consequence may be a decrease in the birth prevalence of these conditions, which has occurred in several countries for some conditions. Different programs target different groups (high school, premarital, couples before conception, couples attending fertility clinics, and pregnant women) as does the governance structure (public health initiative and user pays). Ancestry-based offers of screening are being replaced by expanded carrier screening panels with multiple genes that is independent of ancestry. This review describes screening in Australia, Cyprus, Israel, Italy, Malaysia, the Netherlands, Saudi Arabia, the United Kingdom, and the United States. It provides an insight into the enormous variability in how reproductive carrier screening is offered across the globe. This largely relates to geographical variation in carrier frequencies of genetic conditions and local health care, financial, cultural, and religious factors.  相似文献   
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We investigated the behavioral effects of exposure to waterborne phytoestrogens in male fighting fish, Betta splendens. Adult fish were exposed to a range of concentrations of genistein, equol, beta-sitosterol, and the positive control 17beta-estradiol. The following behaviors were measured: spontaneous swimming activity, latency to respond to a perceived intruder (mirror reflection), intensity of aggressive response toward a perceived intruder, probability of constructing a nest in the presence of a female, and the size of the nest constructed. We found few changes in spontaneous swimming activity, the latency to respond to the mirror, and nest size, and modest changes in the probability of constructing a nest. There were significant decreases, however, in the intensity of aggressive behavior toward the mirror following exposure to several concentrations, including environmentally relevant ones, of 17beta-estradiol, genistein, and equol. This suggests that phytoestrogen contamination has the potential to significantly affect the behavior of free-living fishes.  相似文献   
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This paper describes a project undertaken during 2001/2002 which developed a method for valuing hedgerows adjacent to the inland waterway network of Great Britain. The method enables the landowner, British Waterways, to manage their valuable environmental asset to achieve a good level of biodiversity and robust habitat balanced against the heavy amenity use the 3000 km canal network endures. Valuation techniques were developed using a combination of new and existing ecological indices for components of biodiversity, hedgerow structure and amenity, and synthesised into an index in an innovative combined approach. The resultant index was then applied to a sample 20 km section of hedge alongside the Grand Union Canal in Southeast England. The results obtained reflect the hedgerows' present value, and highlight factors that might improve or limit their future increase in value. The results from the case study application also demonstrate that there is a positive relationship between hedgerow structure and biodiversity, and that hedgerows in urban areas are less biodiverse and structurally sound than those in rural areas. Furthermore, there is a zone within rural areas influenced by the adjacent urban areas and/or higher amenity use. The paper concludes with an assessment of the approaches' strengths and weaknesses with a view to its compatibility with other hedgerow evaluations, such as HEGS, its use by other agencies or landowners, and to aid hedgerow management and future development.  相似文献   
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