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Using the reproductive capacity of fish appears to be a suitable approach for risk assessment in the aquatic environment since fish are a typical representative thereof and in addition they are of considerable societal value. Generally the early embryonic stages are considered to be one of the most sensitive parts of a fish's life cycle. A method has been developed to use the state of health of live, naturally spawned fish embryos from plankton samples for biological effects monitoring. During the years 1985–1987 in the southern North Sea and in 1991–1992 in the whole of the North Sea fish eggs were sampled from surface waters and examined for developmental abnormalities. Elevated embryo malformation rates were detected in the plume of the major rivers Elbe and Rhine as well as along the eastern coast of England. Occurring malformations are thought to be pollution-related and may be used to define areas of environmental deterioration. The method is discussed in view of its suitability for biological effects monitoring using malformations in fish embryos as biomarkers.  相似文献   
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Trisomy 7 mosaicism was detected prenatally in cultured amniocytes but not in fetal lymphocytes. The child that was born had pigmentary changes of the skin and facial asymmetry suggestive of a chromosomal mosaicism. Skin fibroblasts were studied and trisomy 7 mosaicism was confirmed. At 3 years of age the boy had developed mentally within normal limits. However, dysmorphic findings include sparse hair, short leftpalpebral fissure, ptosis of the left eyelid, strabismus, enamel dysplasia, low-set and posteriorly rotated ears and undescended testes. These findings share some common features with previously reported cases of trisomy 7 mosaicism. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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The biofiltering capacity, distribution patterns and degradation of the antimicrobial sulfamethazine(SMT) by halophyte Chenopodium quinoa under hydroponic conditions and its further biodegradation through anaerobic digestion were evaluated. C. quinoa was cultivated for a complete life cycle under different concentrations of SMT(0, 2 and 5 mg/L) and sodium chloride(0 and 15 g/L). C. quinoa is able to uptake and partially degrade SMT. The higher the SMT concentration in the culture medium, the higher the SMT content in the plant tissue. SMT has different distribution patterns within the plant organs, and no SMT is found in the seeds.Dry crop residues containing SMT have a great potential to produce methane through anaerobic digestion and, in addition, SMT is further biodegraded. The highest specific methane yields are obtained using crop residues of the plants cultivated in the presence of salt and SMT with concentrations between 0 and 2 mg/L.  相似文献   
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