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991.
C. Thauvin-Robinet P. Callier N. Laurent T. Rousseau A. Masurel-Paulet N. Marle F. Huet P. Sagot L. Faivre F. Mugneret 《黑龙江环境通报》2007,27(6):555-559
Occipital encephalocele belongs to the family of neural tube defects, which occur in one among 2000 to 5000 live births. Syndromic encephaloceles include Meckel–Gruber syndrome and various chromosomal abnormalities. We report on a fetal case (13 WG) with bilateral cleft lip and palate, choanal atresia, occipital encephalocele, bilateral club feet, bilateral multicystic kidneys, enlarged bladder and urethral atresia. The fetal chromosome analysis showed a maternally inherited unbalanced translocation between the short arm of chromosome 1 and the long arm of chromosome 14, resulting in 1p35-pter deletion and 14q32-qter duplication (46,XY,der(1),t(1;14)(p35;q32)). Since the chromosomal breakpoints have not previously been implicated in syndromic encephalocele, this observation is of interest for the identification of other genes responsible for occipital encephalocele. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
992.
Prenatal diagnosis of charcot-marie-tooth disease type 1a (CMT1A) using molecular genetic techniques
R. Navon V. Timmerman A. Löfgren P. Liang E. Nelis M. Zeitune Professor Dr. C. Van Broeckhoven Ph.D. 《黑龙江环境通报》1995,15(7):633-640
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication. 相似文献
993.
994.
The concentrations of bisphenol A (BPA) contained in landfill leachates from solid waste disposal sites were measured. The
concentrations of BPA contained in leachates from industrial waste sites were in the range below the detection limit to 2800 μg/l,
while those from municipal sites were in the range 26–8400 μg/l. The leachates from ash-rich sites contained relatively lower
concentrations of BPA compared with organic-rich leachates. It is suggested that BPA concentration increases with time after
the completion of reclamation in the case of ash-rich sites, whereas the concentration of BPA decreases with time in the case
of organic-rich sites. A 7-year survey on a site in Japan showed neither a decrease nor an increase in the concentration of
BPA during on-going reclamation. A leachate from a site in the Philippines contained high concentrations of BPA. A slight
positive correlation was found between BPA concentrations and total organic carbon (TOC). A major portion of the BPA in leachates
was found in dissolved and organic unassociated fractions, which cannot be precipitated by coagulation. More than 99.9% of
the BPA contained in raw leachates was removed by a conventional series of treatment processes consisting of biological treatment,
coagulation, sedimentation, sand filtration, and activated carbon adsorption.
Received: May 29, 2002 / Accepted: October 17, 2002 相似文献
995.
996.
三峡库区发展态势与问题 总被引:13,自引:0,他引:13
陈国阶 《长江流域资源与环境》2003,12(2):107-112
近10年,三峡库区经济得到较大发展,GDP总量,人均GDP成倍增长,基础设施建设成绩斐然。但与全国和发达地区比较,差距仍在扩大。产业结构层次低,效益低,外资投资和外贸投资环境差等问题依然十分突出。山地灾害,环境污染,生态退化等问题仍十分严重,对重庆未来发展造成巨大压力。因此,对三峡库区近年的发展应有客观的评估。应该认识到,三峡库区发展滞后是自然因素,历史因素长期综合过程的产物,三峡库区的发展需要经历长期艰苦奋斗的过程,不可能在短期内就能“赶超”,更不可能仅靠一个特大工程的带动而导致改观。当前,加大国家对三峡库区的投入,特别是扶持库区基础设施建设是必要的,但库区的发展不能长期依赖国家的投入,应该培育自身的发展能力,改善投资环境,吸引外资,吸引私人和集体投资;要在竞争中求发展。发展过程中,要十分重视库移民的可持续发展问题,及生态安全,环境污染治理和山地灾害控制问题,应进行产业重构,培植优势产业,名牌企业和名牌产品;合理利用劳动力资源;发挥重庆主城区和三峡工程对经济的拉动作用。 相似文献
997.
Kendall J. Bryant 《Journal of environmental psychology》1984,4(1):43-60
Two perspectives in the analysis of pointing and mapping tasks as the measure of representations of the large-scale environment are examined. These two perspectives are: (1) an individual difference approach; and (2) a cognitive representational approach. Convergence between methods assessing the same geographical/spatial knowledge is necessary as evidence for the existence of unified cognitive-spatial representations of the environment.Three sets of analyses interrelate performance on pointing and mapping tasks. In the first analysis, a confirmatory factor analytic model is applied to short tests of pointing and mapping accuracy to determine whether one or two factors are needed to account for covariation between the tests. In the second analysis, covariation among errors in pointing and mapping of specific locations is partitioned into general and specific method factors using the Schmid-Leiman procedure. In the third analysis, pointing errors for identical locations within the mapping and pointing tasks are directly compared on the basis of directional errors.The three analyses indicate that: (1) tests of pointing and mapping measure highly related abilities; (2) the targets used in pointing and mapping tasks are of differential importance in identifying general and specific method factors; and (3) there is little or no direct correspondence between directional errors made in pointing tasks and those occurring in mapping tasks for the same locations.When results of the three analyses are examined in relationship to criteria for convergence of pointing and mapping tasks, little evidence is found to suggest that directional errors in these tasks arise from a unified mental representation of the geographical environment. However, substantial predictable individual differences are apparent for both tasks. 相似文献
998.
Inhibin A is a useful prenatal marker of Down syndrome. Currently, the available enzyme-linked immunosorbent assays (ELISAs) for inhibin A are based upon the same paired monoclonal antibodies. In the present study we have confirmed for one of those ELISAs that short-term sample storage as whole blood leads to a significant decline in detectable inhibin A and that this is most likely due to erythrocyte catalase interference with a critical oxidation step in the assay. While this interference can be eliminated by heating the samples pre-assay, this process is labour intensive. In the present study we have demonstrated that the addition of 3-amino-1,2,4-triazole (AT), a catalase ‘suicide’ inhibitor, also prevents the decline of inhibin A levels in samples stored as whole blood. We suggest that the addition of AT to samples prior to assay is a simple modification to the inhibin A ELISA that affords optimum performance. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
999.
1000.
To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1-propranol (AMP) was investigated to determine its regeneration behavior as a CO_2 absorbent. The CO_2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO_2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA). 相似文献