On the parental origin of the X's in a prenatally diagnosed 49,XXXXX syndrome

A 49,XXXXX fetus was detected in amniotic fluid cell cultures from a 39-year-old mother. On ultrasonography, growth retardation and bilateral radioulnar synostosis were found. Additional clinical manifestations were mild facial anomalies and hypoplastic ovaries depleted of oocytes. Molecular analysis showed that this aneuploidy arose by successive maternal non-disjunction.     

Application of surface molecular imprinting adsorbent in expanded bed for the adsorption of Ni(2+) and adsorption model

A new surface molecular imprinting adsorbent (SMIA) was used in an expanded bed. The expansion ratio and adsorption performance were studied at different volumetric rates, inlet concentrations, and pH values. A model based on the Adams-Bohart adsorption model of breakthrough curves was established. The predicted curves had good agreement with the experimental curves. The breakthrough time (T(1/2)) decreased with increasing inlet concentration when the outlet concentration was half the initial concentration (C/C(0)=0.5). The inlet concentration had little effect on the adsorption rate constant (k(1)) value when the initial concentration (C(0)) was above 150 mg/L. However, T(1/2) values increased with increasing initial pH of the inlet solution, and the k(1) value decreased due to the competition between H(+) and Ni(2+).     

Advances in research of airborne microbes in subway systems北大核心CSCD

Subway systems are indispensable for transportation in modern cities, with the air being easily polluted by microbes owing to the enclosed and crowded environment. The microbiological characteristics of subway aerosols have attracted the attention of researchers worldwide during recent years. This review aimed to evaluate the sampling and analyzing methods suitable for detecting airborne microbes in subway systems. Active air sampling methods and molecular biology techniques based on polymerase chain reaction (PCR) such as 16S rRNA gene sequencing, metagenomics, and quantitative PCR demonstrated great potential in microbial analysis of aerosols because they can provide accurate and comprehensive information. Temporal and spatial distributions of airborne microbes, as well as the factors influencing their distribution characteristics, were also discussed by critically reviewing worldwide literature on subway microbiome studies. The concentration and composition of airborne bacteria and fungi in subway can vary dramatically with time and space. The critical factors determining microbial community structure and composition include temperature, relative humidity, carbon dioxide concentration, number of passengers, presence of platform screen door, ventilation systems, and so on. The review suggests that future studies on standardized sampling and analyzing protocols are required to obtain contamination levels of subway airborne microbes and to establish the relationship between microbial monitoring data and public health risks. © 2018 Science Press. All rights reserved.     

黑眉锦蛇人工越冬试验

作者于1994年12月～1995年4月对黑眉锦蛇进行了人工越冬试验。试验结果发现此蛇冬眠温度为5～8℃,高于8℃以上时出现活动;阳光直射可调节蛇洞温度;保持供应饮水在越冬期很重要;越冬期自然损失率为18.09％,体长并有缩短的现象,其体长缩短率为4.55％;冬季仍然出现蜕皮现象。     

层次分析法在水库水质评价中的模型设计及应用

目前．评价水质的因子有总磷、总氮、重金属元素、溶解氧等多项指标，评价方法一般有模糊数学法、隶属度法及灰色建模法等。但这些评价方法大都针对水体等级的评价，而对指标权重确定的方法相对较少。对于一个水库或湖泊，确定各指标间的权重关系，对评价水库或湖泊整体水质好坏有重大意义。通过运用层次分析法，以山仔水库中的七里、库心、日溪口和坝前4个点为例对水质进行评价，最后确定各污染因子间的权重关系，得出该库中总磷污染最重，这与当年政府为除磷而关闭周边养猪厂的做法相符。     

加权灰色局势决策法在环境空气质量评价中的应用

应用加权灰色局势决策法对１０ 个样本的环境空气质量进行评价，结果表明，该法能准确地评价环境空气质量状况，可以为环境决策提供比较可靠的依据，对于环境管理与决策具有重要意义。     

分子生物学在生物强化处理环境污染物中的应用

综述了分子生物学的相关技术在生物强化处理环境污染物中的应用，主要包括：通过分子生物技术育种、筛选、构建高效降解污染物微生物菌株；提供更科学、快捷、准确多样的环境监测和环境评价技术手段；探索微生物与环境污染物间的相互关系，及微生物降解污染物的有关基因定位，相关主要技术有：核酸探针检测、DNA-DNA杂交，rRNA和rRNA基因序列分析。质粒指纹图谱分析、聚合酶链式反应（PCR）、低分子量PNA分布图及由PCR技术发展而带动的基因多态性技术，如变性梯度凝胶电泳（DGGE）、随机扩增多态性DNA技术（RAPD）等。     

First-trimester biochemical and molecular diagnoses using chorionic villi: High accuracy in the U.S. collaborative study

The accuracy of biochemical and molecular prenatal diagnoses using chorionic villi as the fetal source was assessed by seven centres participating in the NICHD collaborative study on the safety and accuracy of chorionic villus sampling (CVS) and amniocentesis. Of 601 pregnancies studied, biochemical methods were used to determine the diagnosis in 283 fetuses at risk for 35 different metabolic disorders. Fifteen different lysosomal storage diseases accounted for 81 per cent of the biochemical prenatal diagnoses performed, with 57 per cent of these pregnancies at risk for Tay-Sachs disease. No errors were made in the biochemical diagnoses that predicted affected or unaffected fetuses. However, the diagnoses of certain disorders (e.g., mucopolysacchariodosis type IH, metachromatic leukodystrophy, and Krabbe disease) occasionally required confirmatory studies in cultured amniocytes because the enzyme results were inconclusive in direct and/or cultured villi or due to the presence of a pseudodeficiency allele. Of these, only the diagnosis of a fetus at risk for Krabbe disease remained inconclusive after special studies to discriminate between mutant and pseudodeficiency alleles. Recombinant DNA techniques were used to predict the diagnosis of 318 fetuses at risk for 16 different disorders in which the defective disease gene could be detected either directly or by linkage analysis to a nearby polymorphic marker. Of these, 32 per cent were for haemoglobinopathies, 25 per cent for cystic fibrosis, 24 per cent for Duchenne or Becker muscular dystrophy, and 7 per cent for haemophilias. Pregnancies at risk for known disorders with specific molecular lesions (e.g., sickle cell disease) were accurately diagnosed in direct and/or cultured villi. Diagnoses requiring analyses with closely linked polymorphic markers were occasionally uninformative or inconclusive. Maternal contamination was not reported in any biochemical or molecular-based diagnosis. These studies document the high accuracy and rapidity of both biochemical and mutation-specific prenatal diagnoses with direct and cultured chorionic villi.     

有机氯化物分子连接性与毒性的相关性

导出了用一阶价分子连接性指数（Ｘ）预测有机氯化物对Ｊｉａ卑鱼毒性（ｌｏｇＬＣ５０）的相关方程。分子连接指数由化合物的分子结构很容易计算出。该相关性方程含有两个变量，预测有机氯化物的毒性范围达３．５个数量级。其相关系数和标准差分别为０．９８１和０．１９。应用该相关方法可以预测大范围有机氯化物的毒性。     

辽河铁岭段主要支流水质污染的综合决断

采用模糊集合理论，对辽河铁岭段的四条支流，西辽河、东辽河、招苏台河和条子河分别在枯水期、丰水期、平水期做出水质污染的综合决断，由结果可看出四条河流水质污染的不同性，为治理辽河污染提供了一定的理论依据。