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211.
D. Geneviève E. Walter P. Gorry M. L. Jacquemont L. Dupic V. Layet A. Munnich V. Cormier-Daire M. Dommergues S. Lyonnet D. Mitanchez 《黑龙江环境通报》2005,25(11):997-999
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
212.
Nicolas Gruchy Eleonore Blondeel Nathalie Le Meur Géraldine Joly-Hélas Pascal Chambon Marianne Till Martine Herbaux Adeline Vigouroux-Castera Aurélie Coussement James Lespinasse Florence Amblard Mélanie Jimenez Pocquet Camille Lebel-Roy Frédérique Carré-Pigeon Elisabeth Flori Francine Mugneret Sylvie Jaillard Catherine Yardin Radu Harbuz Marie-Agnès Collonge-Rame Philippe Vago Mylène Valduga Nathalie Leporrier François Vialard 《黑龙江环境通报》2016,36(6):523-529
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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
216.
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
217.
Courting virtual rivals increase ejaculate size in sticklebacks (<Emphasis Type="Italic">Gasterosteus aculeatus</Emphasis>) 总被引:1,自引:0,他引:1
Marc?ZbindenEmail author Dominique?Mazzi Reto?Künzler Carlo?R.?Largiadèr Theo?C.?M.?Bakker 《Behavioral ecology and sociobiology》2003,54(3):205-209
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
218.
Processing and characterization of a new biodegradable composite made of a PHB/V matrix and regenerated cellulosic fibers 总被引:1,自引:0,他引:1
Ch. Bourban E. Karamuk M. J. de Fondaumière K. Ruffieux J. Mayer E. Wintermantel 《Journal of Polymers and the Environment》1997,5(3):159-166
In this study, a biodegradable composite consisting of a degradable continuous cellulosic fiber and a degradable polymer matrix—poly(3-hydroxybutyrate)-co-poly(3-hydroxyvalerate
(PHB/V with 19% HV)—was developed. The composite was processed by impregnating the cellulosic fibers on-line withPHB/V powder in a fluidization chamber. The impregnated roving was then filament wound on a plate and hot-pressed. The resulting
unidirectional composite plates were mechanically tested and optically characterized by SEM. The fiber content was 9.9 ±0.9
vol% by volumetric determination. The fiber content predicted by the rule of mixture for unidirectional composites was 13.8
±1.4 vol%. Optical characterization showed that the fiber distribution was homogeneous and a satisfactory wetting of the fibers
by the matrix was achieved. Using a blower to remove excess matrix powder during processing increased the fiber content to
26.5 ±3.3 vol % (volumetric) or 30.0 ±0.4 vol% (rule of mixture). The tensile strength of the composite parallel to the fiber
direction was 128 ±12 MPa (10 vol% fiber) up to 278 ±48 MPa (26.5 vol% fiber), compared to 20 MPa for the PHB/V matrix. The
Young’s modulus was 5.8 ±0.5 GPa (10 vol% fiber) and reached 11.4 ±0.14 GPa (26.5 vol% fiber), versus 1 GPa for the matrix. 相似文献
219.
Naccari F Giofrè F Licata P Martino D Calò M Parisi N 《Environmental monitoring and assessment》2004,96(1-3):191-202
At present, there are no specific studies on the evaluation of environmental toxicological risks in Calabria (south of Italy) and on the presence of contaminants in the fauna of this region. The aim of the present research was to investigate the levels of contamination by OC pesticides and PCBs in some organs and tissues of wild boars (utilized as 'biological indicator') from various areas of Calabria. Quantitative determinations of organochlorines were carried out using GC-ECD and confirmed with GC-MS in 154 samples from wild boars (heart, liver, lung, kidney, muscle tissue and spleen) during the hunting season from 2000 to 2002. The results indicate the low residual levels of DDE in 8 samples and DDT in 4 samples and PCBs residues (Aroclor 1232) below the detection limits were found. Therefore, these results show that the Calabria region is not at contamination risk from organochlorines and moreover is free from health problems for the consumer of boar meat. 相似文献
220.
Arini A Baudrimont M Feurtet-Mazel A Coynel A Blanc G Coste M Delmas F 《Journal of environmental monitoring : JEM》2011,13(12):3386-3398
Despite a significant decrease in the metallic waste emissions from an industrial site and a remediation process initiated in 2007, the Riou-Mort watershed (southwest France) still exhibits high Cd and Zn concentrations. Metal wastes have long been proven to significantly disturb aquatic communities. In this study, bioaccumulation capacities and responses to the chemical improvement of the hydrosystem were assessed for a year along the contamination gradient through the comparison of two biological models: Corbicula fluminea and periphytic biofilms, both considered as good bioindicators. Bioaccumulation results confirmed the persistence of water contamination in Corbicula fluminea and biofilms with, respectively, maximum Cd concentrations reaching 80.6 and 861.2 μg gDW(-1), and Zn concentrations 2.0 and 21.3 mg gDW(-1). Biofilms exhibited bioaccumulation in close correlation with water contamination, while Corbicula fluminea presented Cd bioaccumulation clearly regulated by water temperature and metal concentrations, affecting the ventilatory activity, as revealed by condition indices measurements. Also, a linear regression using Cd bioaccumulation and temperature () showed that below approximately 6 °C Corbicula fluminea did not appear to accumulate metals. Bioconcentration factors (BCFs) were higher in biofilms in comparison with Corbicula fluminea and showed the great accumulation capacity of suspended particulate matter in biofilms. However, bioaccumulation capacities are known to be influenced by many factors other than metal concentrations, such as temperature, water oxygenation or plankton and nutrient concentrations. Thus, this study demonstrates the power of a combined assessment using both Corbicula fluminea and biofilms as bioindicators to give a more integrated view of water quality assessment. Finally, when comparing our results with previous studies, the start of hydrosystem restoration could be shown by decreasing bioaccumulation in organisms. 相似文献