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121.
Aromatic DNA adducts in the livers and blood of grey mullet (Mugil sp.) have been monitored between 1993 and 1996 by the isolation of DNA and the postlabeling of the DNA adducts with 32P. The grey mullet were sampled from three well-characterised harbours, two in the northeastern Mediterranean and one in the northeastern Black Sea near Trabzon close to a site of aquaculture. One of the northeastern Mediterranean harbours was highly polluted with polynuclear aromatic hydrocarbons (PAHs) and was rich in inorganic nutrients. Larger grey mullet lived in this harbour than the other harbours and their livers possessed approximately 100 aromatic DNA adducts per 10(8) nucleotides. The livers from grey mullet in the other two harbours possessed < or = 25 aromatic DNA adducts per 10(8) nucleotides but these concentrations depended on a variety of factors. Blood cell being regenerated more rapidly than liver cells, it is found that generally the ratio of DNA adduct concentrations in piscine liver and blood will increase with the pollution of the surrounding marine environment. Fishes are acceptable models for the metabolism of xenobiotics and the associated formation of harmful aromatic DNA adducts in organisms.  相似文献   
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/ The National Environmental Policy Act of 1969 (NEPA) was intended to promote a systematic, comprehensive, interdisciplinary approach to planning and decisionmaking, including the integration of the natural and social sciences and the design arts. NEPA critics have cited three key shortcomings in its implementation: (1) a lack of engagement with the NEPA process early in the planning process through interdisciplinary collaboration; (2) a lack of rigorous science and the incorporation of ecological principles and techniques; and (3) a lack of emphasis on the Act's substantive goals and objectives. In recent years and independent of NEPA, a policy of ecosystem management has been developed, which represents a fundamental change from a fragmented, incremental planning and management approach to a holistic, comprehensive, interdisciplinary land and resource management effort. We postulate that by incorporating ecosystem management principles in their planning and decisionmaking, federal agencies can address the shortcomings in NEPA implementation and move closer to NEPA's intent. A case analysis of EISs prepared by the USDA Forest Service before and after adopting an ecosystem management approach supports our hypothesis.  相似文献   
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The Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) conducted joint research on dust explosions by studying post-explosion dust samples. The samples were collected after full-scale explosions at the PRL Lake Lynn Experimental Mine (LLEM), and after laboratory explosions in the PRL 20-L chamber and the Fike 1 m3 chamber. The dusts studied included both high- and low-volatile bituminous coals. Low temperature ashing for 24 h at 515 °C was used to measure the incombustible content of the dust before and after the explosions. The data showed that the post-explosion incombustible content was always as high as, or higher than the initial incombustible content. The MSHA alcohol coking test was used to determine the amount of coked dust in the post-explosion samples. The results showed that almost all coal dust that was suspended within the explosion flame produced significant amounts of coke. Measurements of floor dust concentrations after LLEM explosions were compared with the initial dust loadings to determine the transport distance of dust during an explosion. All these data will be useful in future forensic investigations of accidental dust explosions in coal mines, or elsewhere.  相似文献   
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The concentration of minerals in the crust forms a continuous distribution between the higher grade reserves mined as ore and the low-grade background mineralization of waste rock. A lognormal distribution could be generated by a mineralization process compatible with the theory of plate tectonics. A computer model of this process is demonstrated. The discussion is extended to other base metals and in particular to the distribution of reduced carbon. Neither base metals nor fossil fuels are ever likely to be exhausted, but they may rise in cost and be superseded by cheaper substitutes.  相似文献   
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Early pregnancy renal anhydramios (EPRA) comprises congenital renal disease that results in fetal anhydramnios by 22 weeks of gestation. It occurs in over 1 in 2000 pregnancies and affects 1500 families in the US annually. EPRA was historically considered universally fatal due to associated pulmonary hypoplasia and neonatal respiratory failure. There are several etiologies of fetal renal failure that result in EPRA including bilateral renal agenesis, cystic kidney disease, and lower urinary tract obstruction. Appropriate sonographic evaluation is required to arrive at the appropriate urogenital diagnosis and to identify additional anomalies that allude to a specific genetic diagnosis. Genetic evaluation variably includes karyotype, microarray, targeted gene testing, panels, or whole exome sequencing depending on presentation. Patients receiving a fetal diagnosis of EPRA should be offered management options of pregnancy termination or perinatal palliative care, with the option of serial amnioinfusion therapy offered on a research basis. Preliminary data from case reports demonstrate an association between serial amnioinfusion therapy and short-term postnatal survival of EPRA, with excellent respiratory function in the neonatal period. A multicenter trial, the renal anhydramnios fetal therapy (RAFT) trial, is underway. We sought to review the initial diagnosis ultrasound findings, genetic etiologies, and current management options for EPRA.  相似文献   
128.
Innovations in water chain are discussed based on experiences in the Netherlands. The available and new technological options, as well as their dissemination in the Netherlands, are presented for the prevailing system with add-on technologies (elongation), and for the emerging separation system with technologies at the source. Numerous new options are available for both systems but these options are rarely used. The low use is explained using economic theories and with practical examples from the Netherlands. In order to foster innovations, the mainstream, evolutionary, and behavioral theories pinpoint respectively the pricing of common goods, broad support of concerted action, and support for innovators’ entry. These actions may all be needed. Experiences with a stakeholder cluster in water management suggest that markets for high value water use invoke innovations and low-cost technology adaptations. The systematic development of services that foster high value water-based activities is recommended.  相似文献   
129.
Fetoscopic endotracheal occlusion (FETO) is a prenatal treatment that may increase survival in severe congenital diaphragmatic hernia (CDH). In the USA, FETO is offered for isolated severe left-sided CDH in the context of an FDA-approved feasibility study. FETO in non-isolated cases of severe CDH is only performed with a compassionate use exemption from US regulatory bodies. Anomalies frequently associated with CDH include congenital cystic lesions of the lung and cardiac defects. We describe two cases of non-isolated severe left-sided CDH that underwent prenatal FETO, survived after birth and underwent postnatal surgical repair. The potential benefit of FETO in this setting is discussed. © 2017 John Wiley & Sons, Ltd.  相似文献   
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