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661.
Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation.  相似文献   
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An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Environmental Science and Pollution Research - Insecticidal treatment is a common practice for the control of stored-product insect pests. Most studies are focused on the direct effects of...  相似文献   
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Environmental Science and Pollution Research - Hydrolysis is one of the most important processes of transformation of organic chemicals in water. The rates of reactions, final chemical entities of...  相似文献   
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Determination of halogen-specific total organic halogen(TOX) is vital for studies of disinfection of waters containing bromide, since total organic bromine(TOBr) is likely to be more problematic than total organic chlorine. Here, we present further halogen-specific TOX method optimisation and validation, focusing on measurement of TOBr. The optimised halogen-specific TOX method was validated based on the recovery of model compounds covering different classes of disinfection by-products(haloacetic acids, haloacetonitriles,halophenols and halogenated benzenes) and the recovery of total bromine(mass balance of TOBr and bromide concentrations) during disinfection of waters containing dissolved organic matter and bromide. The validation of a halogen-specific TOX method based on the mass balance of total bromine has not previously been reported. Very good recoveries of organic halogen from all model compounds were obtained, indicating high or complete conversion of all organic halogen in the model compound solution through to halide in the absorber solution for ion chromatography analysis. The method was also successfully applied to monitor conversion of bromide to TOBr in a groundwater treatment plant. An excellent recovery(101%)of total bromine was observed from the raw water to the post-chlorination stage. Excellent recoveries of total bromine(92%–95%) were also obtained from chlorination of a synthetic water containing dissolved organic matter and bromide, demonstrating the validity of the halogen-specific TOX method for TOBr measurement. The halogen-specific TOX method is an important tool to monitor and better understand the formation of halogenated organic compounds, in particular brominated organic compounds, in drinking water systems.  相似文献   
668.
The purpose of this study was to determine certain blood biochemical parameters in hens of Isa Brown breed (n = 20) after nickel administration. Animals were divided into four groups (K, P1, P2, P3). Experimental hens (n = 5; in each group) received nickel (NiCl2) as peroral administration in drinking water in various doses (P1 – 0.02 g NiCl2/L; P2 – 0.2 g NiCl2/L; P3 – 2.0 g NiCl2/L of drinking water) for 28 days. The last group – K (n = 5) was the control, receiving no nickel. Biochemical parameters of mineral profile (calcium; phosphorus; magnesium; sodium; potassium) and of energy and enzymatic profile [(glucose; total cholesterol; total proteins; triglycerides; alanine aminotransferase (ALT) aspartate aminotransferase (AST) gamma glutamyl transferase (GGT) and glutamatdehydrogenase (GLDH)] were analyzed in blood serum on Day 0, 7, 14, 21 and 28 of the experiment. Average levels of mineral metabolism parameters were relatively stable apart from calcium. The evaluation registered a significant decrease in calcium during the experiment mainly in the group with highest nickel concentration in drinking water. No significant differences were detected between groups in energy and enzymatic profile apart from the concentrations of ALT on Day 7. In conclusion, there were significant associations between nickel levels and calcium and ALT in blood serum of the hens. No significant differences were detected in other biochemical parameters of mineral profile (P, Mg, Na, K) and energy and enzymatic profile (glucose, total cholesterol, total proteins, triglycerides, AST, GGT and GLDH) after nickel administration. Our results may contribute to an evaluation of reference levels of analyzed parameters, to monitor the health and nutritional status of hens. In this study also the negative effect of nickel mainly on calcium metabolism was detected.  相似文献   
669.
We describe the first case of mosaic supernumerary marker iso (8p) displaying a karyotype discordance between chorionic villi (CV) and amniotic fluid (AF) cultures during prenatal cytogenetic diagnosis. In the first trimester, cytogenetic analysis after chorionic villi sampling (CVS) was normal in all metaphases in the short-term cytotrophoblast cell culture, but an undefined supernumerary marker was detected in 60% of mesenchymal cells in the long-term CV culture. Informed of the mosaicism, the couple selected amniotic fluid sampling as a second-trimester confirmatory diagnostic procedure. The supernumerary marker was absent in all of the 25 available AF cells metaphases. The prospective parents received genetic counselling and were informed that the discordance could be interpreted as a placental confined mosaicism or as a true foetal mosaicism with low percentage of affected cells. The couple opted to continue the pregnancy. In the second month of life, the child had abnormal development with severe psychomotor delay and frequent episodes of epilepsy. Postnatal cytogenetic extensive re-evaluation discovered that the previously detected supernumerary marker was indeed an isochromosome (8p) rearrangement present at low frequency in 5% of the blood lymphocytes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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