Rare non-mosaic trisomies in chorionic villus tissue not confirmed at amniocentesis

This paper reports eight cases of non-mosaic, rare, and typically lethal trisomies diagnosed in chorionic villi and not confirmed by amniocentesis. Four cases were 47,XX, + 16; two cases were 47,XX, +2; one was 47,XX, + 12; and one was 47,XY, +7. There have been no known complications in any of these gestations. These eight cases were found in a series of approximately 12 000 samples processed in our laboratory (0.07 per cent). We conclude that (1) rare non-mosaic trisomy not reflecting the fetal condition is an occasional source of diagnostic ambiguity in chorionic villus sampling; and (2) when encountered, a follow-up amniocentesis should be recommended to the patient to confirm or rule out the abnormality. We propose the term ‘confined placental abnormality’ to describe non-mosaic trisomies and other related abnormalities found only in chorionic tissue.     

功能区排放负荷污染系数百分比分配法研究

在考虑了总量控制区风频、风速和各功能区位置及污染源“影响范围”等影响因素的条件下，提出了“平均下风距离”的概念，从而建立了一种更为科学、合理的总量控制区内功能区排放负荷分配新方法。通过与 总量控制A值法所提出的面积分配方法相比较，验证了新方法的合理性和有效性。     

Chorionic villus sampling—short-term versus long-term culture in a subtle 2; 18 translocation

Prenatal diagnosis on chorionic villous tissue was performed for a woman with the karyotype 46,XX,t(2;18)(q32;q12)—a subtle ‘difficult’ translocation. The case illustrates the necessity of good quality cytogenetics for accurate prenatal diagnosis. For chorionic villi this can be obtained only with long-term culture.     

Transabdominal chorionic villus sampling: Analysis of 350 consecutive cases

We report a series of 350 patients submitted to transabdominal chorionic villus sampling (CVS). A technique using two ultrasound-guided needles and a suction pump was used. In most cases, the procedure was performed between 9 and 13 weeks. Twenty-one pregnancies were selectively terminated; nine spontaneous abortions followed the procedure and one fetal loss after 28 weeks was recorded; 153 pregnancies are in progress and 169 delivered fetuses are alive and well. Transabdominal biopsy is a feasible and effective technique for CVS.     

Spontaneous abortion after transcervical chorionic villus sampling: A case report

A case of spontaneous abortion after transcervical CVS is presented. Despite no evidence of bacteria in the vagina and cervix prior to sampling and the prophylactic use of Metronidazole, pathological evidence of chorioamnionitis was found. The implications of this are discussed.     

灰色理论模型预测城市垃圾量

利用灰色理论模型 ,采用非线性微分方程拟合 ,可较好地预测城市垃圾的产生量。运用最小二乘法 ,通过MATALAB程序求出了模型中的参数 ,假设检验结果表明 ,该模型有较高的预测精度。根据上述模型 ,预测娄底市未来30a的总垃圾预测量为 80 4 90万t     

循环流化床锅炉床温控制方法

就目前电厂循环流化床锅炉运行中存在的床温波动问题，讨论了导致床温波动的因素，并针对性地提出了控制床温的一些措施。     

利用WEBGIS实现地震灾害信息数据的管理

介绍了WEBGIS技术的特点、基本原理和实现方法，及其在管理海量地理数据中的优势，并构建了基于WEBGIS的地震灾害信息数据的主体框架。     

Demonstration of Line Transect Methodologies to Estimate Urban Gray Squirrel Density

Sciurus carolinensis ) have been labor intensive and costly, I demonstrate the use of line transect surveys to estimate gray squirrel density and determine the costs of conducting surveys to achieve precise estimates. Density estimates are based on four transects that were surveyed five times from 30 June to 9 July 1994. Using the program DISTANCE, I estimated there were 4.7 (95% CI = 1.86–11.92) gray squirrels/ha on the Clemson University campus. Eleven additional surveys would have decreased the percent coefficient of variation from 30% to 20% and would have cost approximately $114. Estimating urban gray squirrel density using line transect surveys is cost effective and can provide unbiased estimates of density, provided that none of the assumptions of distance sampling theory are violated.     

环境保护要依靠公众参与——关于环境保护主要依靠力量的市民调查

环境问题和环境保护已日益深入到社会政治、经济、文化、生活各个领域。在呼吁公众参与的条件下，依靠谁去搞好环境保护？公众是如何看待自己在环境保护中的作用的呢？对这些问题的回答将有助于了解公众关于环境保护的心态，有助于环境保护公众参与政策更具有针对性的实施。本文就这一话题进行了城市居民的抽样调查。调查表明，公众普遍认为，政府和公众参与是搞好环保的主要依靠力量；而公众对环境宣传教育和污染企业的治理以及技术进步的期望较低。本文进一步分析了不同年龄、文化程度、职业和人均月收入带来的影响，以期把握不同层次公众的心态。在此基础上本文就环境宣传教育如何促进公众参与提出了一些思考。