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551.
552.
Omphalocele is one of the most common abdominal wall defects seen in the prenatal period. Once this diagnosis is confirmed, it is important to check the fetal karyotype and thoroughly assess the fetus for other malformations. Prenatal management involves serial assessment of fetal growth and prenatal testing to ensure fetal well-being. Closure of the abdominal wall and replacement of organs into the abdominal cavity can be done directly if the omphalocele is small or in a staged manner if the omphalocele is large. Successful outcomes for these neonates can be optimized with a multidisciplinary team approach to prenatal and postnatal management. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
553.
Charles A. Wilson David L. Nieland John W. Fleecer Antonio Todaro Ronald F. Malone Kelly A. Rusch 《Chemistry and Ecology》2013,29(3-4):321-340
The effects of cement consolidated phosphogypsum (PG) on marine organisms was investigated under natural conditions in four 1000 m2 estuarine ponds. Two ponds were seeded with 160 kg of PG arranged in aggregations of blocks and two ponds received similar mass of sand/cement blocks. Meiofauna were sampled quarterly and PG did not affect total meiofauna or major taxa (nematodes and copepods) density. Abundant species of copepods either were slightly increased in ponds with PG or were inconsistently affected. All ponds were drained after one year. Three species of macroinvertebrates and 15 species of fishes were collected. Diversity indices showed modest but inconsistent variation among ponds. Only Pond 1 (control) and Pond 4 (experimental) had similar species abundances and all ponds showed unique distributions of biomasses among species. Thus, no differences in community structure attributable to the presence of PG could be detected among benthic invertebrates, natant invertebrates, or fishes. 相似文献
554.
International projects frequently struggle with the dilemmas of community participation, whether the community in question
is the object of a development or aid intervention, or is to be persuaded to cooperate on a conservation project. This paper
discusses the challenges facing interventionists and the obstacles and opportunities that local people encounter as they come
into contact with exogenous conservation and development projects. The key issues presented can be summarized as legacy, legitimacy,
agency and communication. We argue that project planners need to understand the history of past interventions in order to
respond appropriately to local expectations. At the same time, the complexity of community leadership and representation complicates
the sometimes conflicting agendas of project developers and communities. Much depends on personal relations, individual agency,
and initiative. Finally, the physical means of communication—language, print and broadcast media, transport and telecommunications—are
important aspects to consider when assessing the limitations to community participation. Although there have been valuable
successes in international projects in Russia, as in other regions of the world, a better understanding of community participation
is needed to ensure more effective and sustainable means for engaging communities in project development and implementation.
This paper explores these questions through a locally-grounded analysis based on the academic research and practitioner experience
of the two authors in the remote home of a World Heritage site—the Kamchatka Peninsula, in the Russian Far East. 相似文献
555.
R. Douglas Wilson 《黑龙江环境通报》2008,28(7):619-625
Fetal thoracic lung anomalies are rare. The specific diagnosis can be made by utilizing ultrasound, magnetic resonance imaging (MRI), and Doppler studies. Perinatal surveillance is required for large lesions and mediastinal shift regardless of the pathological diagnosis. These can cause physiological changes in the cardiovascular system with resulting hydrops. In utero therapies are variable but with no large randomized trials to compare risks and benefits. In most cases of fetal lung lesions, continued observation with postnatal therapy is the outcome. When fetal hydrops is present or impending, in utero fetal therapy is required to try to reverse that pathological course associated with fetal or neonatal death. Maternal morbidity is increased with the development of MIRROR syndrome following the presence of long-standing fetal hydrops and possible surgical procedures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
556.
Wilson WE Stanek J Han HS Johnson T Sakurai H Pui DY Turner J Chen DR Duthie S 《Journal of the Air & Waste Management Association (1995)》2007,57(2):211-220
Because of recent concerns about the health effects of ultrafine particles and the indication that particle toxicity is related to surface area, we have been examining techniques for measuring parameters related to the surface area of fine particles, especially in the 0.003- to 0.5-microm size range. In an earlier study, we suggested that the charge attached to particles, as measured by a prototype of the Electrical Aerosol Detector (EAD, TSI Inc., Model 3070), was related to the 1.16 power of the mobility diameter. An inspection of the pattern of particle deposition in the lung as a function of particle size suggested that the EAD measurement might be a useful indicator of the surface area of particles deposited in the lung. In this study, we calculate the particle surface area (micrometer squared) deposited in the lung per cubic centimeter of air inhaled as a function of particle size using atmospheric particle size distributions measured in Minneapolis, MN, and East St. Louis, IL. The correlations of powers of the mobility diameter, Dx, were highest for X = 1.1-1.6 for the deposited surface area and for X = 1.25 with the EAD signal. This overlap suggested a correspondence between the EAD signal and the deposited surface area. The correlation coefficients of the EAD signal and particle surface area deposited in the alveolar and tracheobronchial regions of the lung for three breathing patterns are in the range of Pearson's r = 0.91-0.95 (coefficient of determination, R2 = 0.82-0.90). These statistical relationships suggest that the EAD could serve as a useful indicator of particle surface area deposited in the lung in exposure and epidemiologic studies of the human health effects of atmospheric particles and as a measure of the potential surface area dose for the characterization of occupational environments. 相似文献
557.
Brown GS Betty RG Brockmann JE Lucero DA Souza CA Walsh KS Boucher RM Tezak MS Wilson MC 《Journal of environmental monitoring : JEM》2007,9(7):666-671
Vacuum filter socks were evaluated for recovery efficiency of powdered Bacillus atrophaeus spores from two non-porous surfaces, stainless steel and painted wallboard and two porous surfaces, carpet and bare concrete. Two surface coupons were positioned side-by-side and seeded with aerosolized Bacillus atrophaeus spores. One of the surfaces, a stainless steel reference coupon, was sized to fit into a sample vial for direct spore removal, while the other surface, a sample surface coupon, was sized for a vacuum collection application. Deposited spore material was directly removed from the reference coupon surface and cultured for enumeration of colony forming units (CFU), while deposited spore material was collected from the sample coupon using the vacuum filter sock method, extracted by sonication and cultured for enumeration. Recovery efficiency, which is a measure of overall transfer effectiveness from the surface to culture, was calculated as the number of CFU enumerated from the filter sock sample per unit area relative to the number of CFU enumerated from the co-located reference coupon per unit area. The observed mean filter sock recovery efficiency from stainless steel was 0.29 (SD = 0.14, n = 36), from painted wallboard was 0.25 (SD = 0.15, n = 36), from carpet was 0.28 (SD = 0.13, n = 40) and from bare concrete was 0.19 (SD = 0.14, n = 44). Vacuum filter sock recovery quantitative limits of detection were estimated at 105 CFU m(-2) from stainless steel and carpet, 120 CFU m(-2) from painted wallboard and 160 CFU m(-2) from bare concrete. The method recovery efficiency and limits of detection established in this work provide useful guidance for the planning of incident response environmental sampling for biological agents such as Bacillus anthracis. 相似文献
558.
Elliott JE Harris ML Wilson LK Smith BD Batchelor SP Maguire J 《Environmental pollution (Barking, Essex : 1987)》2007,149(1):114-124
From 1998 to 2001 we examined spatial and temporal variation in uptake of contaminants by surf scoters (Melanitta perspicillata) in the Georgia Basin region of the Pacific coast of Canada. Samples were collected during late fall and early spring at industrialized and reference locations, carcasses examined, and tissues collected for histology, biomarkers, and contaminant analyses. Scoters from both Vancouver and Victoria harbours had significantly higher hepatic concentrations of summation operatorbutyltins than birds from a reference site. In adult male surf scoters, hepatic summation operatorbutyltins increased over the winter at two sites (p=0.02, n=26), while mercury increased (p=0.03, n=15) and selenium decreased at one site (p=0.001, n=15). Body condition decreased over the winter at both the treatment site, Howe Sound (p<0.0001, n=12), and the reference site, Baynes Sound (p=0.02, n=15). Multiple regression analysis using Akaike's Information Criteria (AIC(C)) showed an association between hepatic butyltin concentrations and overall body condition (p=0.06, r=-0.237). 相似文献
559.
Overmyer JP Rouse DR Avants JK Garrison AW Delorenzo ME Chung KW Key PB Wilson WA Black MC 《Journal of environmental science and health. Part. B》2007,42(5):471-480
Fipronil is a phenylpyrazole insecticide used in agricultural and domestic settings for controlling various insect pests in crops, lawns, and residential structures. Fipronil is chiral; however, it is released into the environment as a racemic mixture of two enantiomers. In this study, the acute toxicity of the (S,+) and (R,-) enantiomers and the racemic mixture of fipronil were assessed using Simulium vittatum IS-7 (black fly), Xenopus laevis (African clawed frog), Procambarus clarkii (crayfish), Palaemonetes pugio (grass shrimp), Mercenaria mercenaria (hardshell clam), and Dunaliella tertiolecta (phytoplankton). Results showed that S. vittatum IS-7 was the most sensitive freshwater species to the racemic mixture of fipronil (LC50 = 0.65 microg/L) while P. pugio was the most sensitive marine species (LC50 = 0.32 microg/L). Procambarus clarkii were significantly more sensitive to the (S,+) enantiomer while larval P. pugio were significantly more sensitive to the (R,-) enantiomer. Enantioselective toxicity was not observed in the other organisms tested. Increased mortality and minimal recovery was observed in all species tested for recovery from fipronil exposure. These results indicate that the most toxic isomer of fipronil is organism-specific and that enantioselective toxicity may be more common in crustaceans than in other aquatic organisms. 相似文献