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Gorlin syndrome (GS), also known as nevoid basal cell carcinoma syndrome, is a rare autosomal dominant condition with an estimated prevalence of 1:57 000. GS is associated with congenital malformations and predisposition to neoplasms. The main features observed in patients with GS are basal cell carcinomas, odontogenic keratocysts, skeletal anomalies including scoliosis and bifid ribs, palmar and plantar epidermal cysts, facial dysmorphism, and cerebral falx calcification. More than 100 other clinical manifestations have also been described in the literature including ovarian fibroma, enlarged cerebral ventricles, and lymphatic as well as chylous mesenteric cysts. The Patched (PTCH) gene is responsible for GS when mutated. Here, we report on a prenatal diagnosis of GS in a girl with a chylothorax, a previously unreported feature in GS. We discuss the clinical features observed in this family and we comment on the molecular studies that allowed us to describe a previously unreported Patched gene mutation. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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  ric Darier  Ralf Schü  le 《Local Environment》1999,4(3):317-329
'Think Globally, Act Locally' was one of the most famous slogans of the 1970s environmental movement. Discourses about global climate change are now a vivid illustration of this new 'global thinking'. Although there is a substantial amount of research about global environmental issues and policy initiatives, there is still a gap in understanding of how lay publics actually comprehend global climate change. Using qualitative research method, this study is a comparison of how lay publics in Frankfurt (Germany) and Manchester (UK) perceive these issues and the possible solutions. The study found strong similarities in lay public perceptions in both cities including that (1) awareness of global environmental issues is always contextualised in broader perspectives not exclusively 'environmental', (2) there is a shared and strong sense of global equity based on recognition of differences and (3) there is an ambivalence about the role of environmental 'information'. Differences between lay public perceptions in Manchester and Frankfurt can be explained by specific features of national cultures.  相似文献   
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A major problem facing environmental managers is the necessity to effectively evaluate management alternatives. Traditional environmental assessments have emphasized the use of economic analyses. These approaches are often deficient due to difficulty in assigning dollar values to environmental systems and to social amenities. A more flexible decisionmaking model has been developed to analyze management options for coping with beach erosion problems at the Sandy Hook Unit of Gateway National Recreation Area in New Jersey. This model is comprised of decision-making variables which are formulated from a combination of environmental and management criteria, and it has an accept-reject format in which the management options are analyzed in terms of the variables. Through logical ordering of the insertion of the variables into the model, stepwise elimination of alternatives is possible. A hierarchy of variables is determined through estimating work required to complete an assessment of the alternatives for each variable. The assessment requiring the least work is performed first so that the more difficult evaluation will be limited to fewer alternatives. The application of this approach is illustrated with a case study in which beach protection alternatives were evaluated for the United States National Park Service.Portions of this paper have been excerpted from Sherman and Garès (1978).  相似文献   
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The size and coloration of some body characters seem to influence mate choice in many species. Most animal colours are either structural or based on melanin or carotenoid pigments. It has recently been suggested that carotenoid-based or structural coloration may be a condition-dependent trait, whereas melanin-based coloration is not; a difference that may be highly relevant when studying the evolution of multiple mating preferences. We tested this hypothesis in the great tit (Parus major). The size of the melanin breast band was not correlated to nutritional condition as estimated by the rate of tail growth (ptilochronology), controlling for locality, age, sex, year and season effects. However, the correlation was significant for the hue of yellow breast (carotenoid-based coloration), and the slopes of the regressions of the two pigments to growth bars differed significantly. These results suggest that the expression of the two traits may be regulated by different mechanisms.  相似文献   
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Sperm competition occurs when sperm of two or more males compete to fertilize a given set of eggs. Game-theory models of sperm competition predict that males, which face an increased risk of sperm competition, will invest more sperm in a mating. In the pair-spawning three-spined stickleback ( Gasterosteus aculeatus), males attempt to steal fertilizations (i.e. to sneak) when they are in the courting phase, but not when they are parental. The behaviour of neighbouring males may therefore indicate the risk of sperm competition. We visually confronted males before spawning with computer animations of the same virtual stickleback showing two different behaviours: either courting (high risk of sperm competition) or brood-caring (low risk of sperm competition). We show that males invest significantly more sperm (absolutely and relatively with respect to available sperm in the testes) after the courting stimulus. The relative investment ratio between the courting and the brood-caring treatment was on average 1.75. Three-spined sticklebacks thus seem to assess the risk of sperm competition by the behaviour of neighbours and to adjust their ejaculate accordingly. This result suggests that the evolutionary force of sperm competition has led to precise mechanisms of future risk assessment.  相似文献   
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