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Dr. J. F. Bruch P. Metezeau N. Garcia-Fonknechten Y. Richard V. Tricottet B.-L. Hsi A. Kitzis C. Julien E. Papiernik 《黑龙江环境通报》1991,11(10):787-798
Three monoclonal antibodies (MAbs) against trophoblast (GB17, GB21, and GB25) and flow cytometry were used to sort trophoblast-like cells (TLCs) from peripheral blood of pregnant women. Sorted TLCs were processed for electron microscopy and fetal DNA amplification of the Y-specific sequences from mothers carrying male fetuses. At the ultra-structural level, most of the nucleated cells had the morphology of leucocytes, suggesting maternal contaminants, and we did not find the characteristic features of the free inter-villous trophoblast cells. Nevertheless, polymerase chain reaction (PCR) analysis showed an amplification of Y-specific sequences in two out of three samples of sorted TLCs. These results suggest that besides the maternal leucocytes, sufficient trophoblast nucleated fetal cells can be obtained using cell enrichment by sorting. This sensitive method holds promise for non-invasive prenatal diagnosis of fetal sex and if sufficient Y(positive) nuclei are found, for the diagnosis of selected numerical chromosome abnormalities. 相似文献
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This study examines 45 cases of trisomy 13 and 59 cases of trisomy 18 and reports an algorithm to identify pregnancies with a fetus affected by trisomy 13 or 18 by a combination of maternal age fetal nuchal translucency (NT) thickness, and maternal serum free β-hCG and PAPP-A at 11–14 weeks of gestation. In this mixed trisomy group the median MoM NT was increased at 2.819, whilst the median MoMs for free β-hCG and PAPP-A were reduced at 0.375 and 0.201 respectively. We predict that with the use of the combined trisomy 13 and 18 algorithm and a risk cut-off of 1 in 150 will for a 0.3% false positive rate allow 95% of these chromosomal defects to be identified at 11–14 weeks. Such algorithms will enhance existing first trimester screening algorithms for trisomy 21. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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A. Coulomb L'Herminé A. Aboura S. Brisset L. Cuisset V. Castaigne P. Labrune R. Frydman Dr G. Tachdjian 《黑龙江环境通报》2003,23(11):938-943
Prader–Willi syndrome (PWS) results from either paternal deletion of 15q11–q13, or maternal uniparental disomy (UPD) of chromosome 15 or imprinting center mutation. Prenatal diagnosis of PWS is currently indicated for chromosomal parental translocation involving chromosome 15 and for decreased fetal movements during the third trimester of gestation. Here we present the prenatal diagnosis of PWS during the first trimester of gestation and autopsy findings. Chorionic villus sampling (CVS) was performed for advanced maternal age at 13 weeks' gestation. CVS showed mosaicism including cells with a normal karyotype and cells with trisomy 15. Amniocentesis showed cells with a normal karyotype. Molecular analysis demonstrated that the fetus had a typical PWS abnormal methylation profile and maternal disomy for chromosome 15. Fetal ultrasound examination showed slightly enlarged lateral ventricles and hypoplasic male external genitalia without intra-uterine growth retardation. The autopsy showed a eutrophic male fetus with facial dysmorphy, hypoplasic genitalia, abnormal position of both feet and posterior hypoplasia of the corpus callosum. This report points out that in a karyotypically normal fetus with ambiguous male external genitalia and cerebral anomalies, extensive cytogenetic and molecular biology studies are strongly recommended because of risk of PWS. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
7.
The coastal water of northeast Taiwan island, called 'Yin-Yang Hai' for its distinct yellow colour compared with blue offshore water, was investigated from 1989 to 1990 by the authors. Biological study showed the dominant species of plankton to be Copepoda, Cladocera, planktonic eggs and Diatoma. Dominant species of benthos were young crabs, Amphipoda and Annelida, with Amphipoda usually occurring in heavily polluted areas. Heavy metal data showed that the concentration of copper was high. the copper and iron concentration in algae of the intertidal zone was also high. the concentrations of iron and copper in inshore water were also higher than in offshore water. By comparison of the pH and salinity distribution of this area, we conclude that this coastal water has been polluted by acid waste water from coastal industry. the suspended solids concentration in sea water is high. Flocculation occurring at the boundary of fresh and saline water might be a reason for the distinct yellow colour of the water of this area. Further study is required. 相似文献
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Three procedures for the extraction of coral lipids were compared and a rapid and effective method for future use is suggested. This method was used to measure the lipid content of the branching coral Porites porites (Pallas) and the massive corals Montastrea annularis (Ellis and Solander) and Siderastrea siderea (Ellis and Solander) during July and August 1991. P. porites and M. annularis were sampled on two fringing reefs, each characterised by different water quality affecting light transmission, and at depths of down to 30 m on a barrier reef on the west coast of the island. m. annularis contained, on average, 29% of dry weight as lipid, and there were no significant differences in lipid levels between corals sampled on either fringing reef at 3 and 6 m, or between fringing reefs and the barrier reef at 13, 20 or 30 m depth. Five samples were also taken from a single massive colony of S. siderea at 3 m on a fringing reef and at 13, 20 and 30 m depth on the barrier reef. Values for lipid ranged from 26 to 35% of dry tissue weight. P. porites from 3 and 6 m depth on both fringing reefs contained the same amount of lipid (11% of dry tissue weight). However, at 13 m depth on the barrier reef this coral contained significantly less lipid (8.5% of dry tissue weight). This difference may be attributable to a higher nutritional intake by P. porites on the fringing reefs. 相似文献
9.
P. Spencer Davies 《Marine Biology》1991,108(1):137-144
Energy budgets were determined for small pieces (nubbins) of the coralsPocillopora damicornis, Montipora verrucosa andPorites lobata living at a water depth of 3 m on the fringing reef of Coconut Island, Kaneohe, Hawaii. The budgets were determined for three different types of day: an ideal day with no cloud and an in situ daily integrated irradiance at 3 m of 14.385 E m–2 d–1; a normal day with sporadic cloud cover and daily irradiance of 11.915 E m–2 d–1; and an overcast day with daily irradiance of 6.128 E m–2 d–1. On the ideal day, the energy fixed in photosynthesis was more than that required for respiration and growth of both zooxanthellae and animal components of the association, and there was a predicted loss of between 19.3 and 32.4% of the energy fixed. On a normal day, the total photosynthetic energy fixation was lower and the excess was between 12.1 and 27.9% of the energy fixed. On the overcast day, however, in bothPocillopora damicornis andPorites lobata energy expenditure exceeded photosynthetic energy fixation and the budget was in deficit. Estimates of rate of mucus secretion on an overcast day were derived and, when incorporated into the energy budget, it was predicted that all three species would have a deficit budget, necessitating the catabolism of lipid reserves. From published values for lipid storage in these species it was calculated that the reserves would last from 28 d inPocillopora damicornis to 114 d inM. verrucosa. A model is suggested in which corals draw upon their extensive lipid stores on days of sub-optimal light, replenishing the reserves again when daily light levels are high, and finally excreting the excess energy fixed, as mucus-lipid when the lipid stores are replete. 相似文献
10.
The degradation and corresponding product manifold for the pesticide fipronil was determined in three replicate estuarine mesocosms. Aqueous fipronil concentrations rapidly decreased over the 672 h timescale of the experiment (95% removal). Loss was apparently first-order in fipronil, although there appeared to be a change in the removal mechanism after 96 h that corresponded to a dramatic slowdown in its disappearance. The reduction product of fipronil, fipronil sulfide, was not detected in the water column; however, it formed rapidly in sediments and was identified as the major product of fipronil degradation in the system (20% yield at 672 h, with respect to initial fipronil concentration). Fipronil sulfone is thought to form primarily via biological oxidation; and, although it was generated rapidly in the water column (10% yield), only trace amounts were detected in the sediment (1% yield). The direct photolysis product of fipronil, fipronil desulfinyl, was present in all samples; it formed rapidly in the water column (4% yield) and partitioned into the sediment phase (7% yield) over the course of the experiment. The mass balance on fipronil and associated products was 42% at 672 h. 相似文献