Prenatal diagnosis of sanfilippo disease type C using a simple fluorometric enzyme assay

A new fluorogenic substrate, 4-methylumbelliferyl β-D-glucosaminide, was used for the assay of acetyl CoA:glucosaminide N-acetyltransferase in chorionic villi, cultured villus cells, and amniocytes. Optimal conditions for the assay and the ranges of enzyme activity were established for the various types of fetal cells. This simple fluorometric assay provides a reliable method for early prenatal diagnosis of Sanfilippo disease type C which is more convenient than current methods using radiolabelled substrates. The method was applied to amniotic fluid cells and fetal fibroblasts from an at-risk pregnancy in which an affected fetus was diagnosed by two-dimensional electrophoresis of glycosaminoglycans in the amniotic fluid.     

水生态修复技术在城市河道污染治理工程中的应用

本文以瑞安丰湖河生态修复工程为例,探讨了组合型生态修复技术在河道水环境治理领域的应用效果。该项目采用生态浮床、微孔曝气、微生物菌剂等多种生态技术相结合的模式对受污染的城市河道进行生态修复。河道中的污染物首先可作为生态浮床中挺水植物生长所需营养物质,挺水植物的根系则可为微生物提供优良的生长环境,微孔曝气则大幅度提升河道水体的溶解氧(DO)浓度,从而进一步改善水体的透明度,促进挺水植物的成长、增强微生物的活性,最终整体恢复河道生态系统并使其形成良性循环。运行结果表明,主要目标水质指标COD_(Mn)和DO的改善程度分别为28%和292%,水体清澈度和透明度大大增加,黑臭消失,水体感官明显改善。     

Study on the cementitiousness of asbestos tailings

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饮食业油烟净化技术及影响因素

根据国内饮食业油烟净化技术发展情况和实际应用测试结果 ,就不同规模和排放浓度的饮食业油烟控制提出优化的处理工艺 ;并分析了影响处理效果的因素     

三峡库区1997年平水期水质同步监测的W值法评价

利用Ｗ值法对１９９７年５月５日上午１０时整在长江干流三峡库区段和嘉陵江、乌江进行的水质同步监测结果进行评价，分析了库区水质沿程分布情况，并与１９９６年同步监测结果进行了比较，提出控制库区水污染几项建议。     

Net Ecosystem Production of Boreal Larch Ecosystems on the Yenisei Transect

The study was carried out in the Turukhansk Research Station of Yenisei Transect (65^°46^′N, 89^°25^′E). Larch (Larix gmelinii (Rupr.) Rupr.) is the dominant overstory tree species. The research has been conducted on four permanent test plots in same-age mature (110-year old) and overmature (380-year old) post-fire larch stands of green moss and lichen groups of forest type. Carbon cycle parameters were assessed based on a biometric method. Quantitative analysis of carbon pools and fluxes shows that net ecosystem production of north taiga larch stands averages 32% of net primary production. Sink of atmospheric CO₂ makes 1.22 and 0.74 t C ha^{− 1} year^{− 1} for mature and overmature green moss larch stands, and 0.65 and 0.35 t C ha^{− 1} year^{− 1} for lichen type. Net carbon sink in the tree layer make up 9% of net primary production carbon, ground vegetation – 15%, and dead plant residues accumulation – 8% of atmospheric carbon uptake via photosynthesis.     

东牙溪水库水环境质量评价及保护措施

采用一种新的模糊评价法对东牙溪水库水质进行了富营养化评价，并针对污染现状提出了相应的保护措施。     

洱海湖滨区鱼塘污染状况调查研究

洱海湖滨区有鱼塘１４９．２５公顷，其有机物含量及换水量均与鱼产量成正比，每年向洱海排换水６７１．６万米＾３，输出Ｎ、Ｐ和ＣＰＤ分别为３３．２Ｔ、３．８３Ｔ、和４２０．４Ｔ。目前鱼塘正由混养型向精养型过渡，污染负荷亦将随之升级，必须及早研究，及早治理。     

Human chorionic β-mannosidase: Comparison with β-mannosidase from human cultured fibroblasts

The conditions for assay of β-mannosidase activity in human chorionic villi (CV) were studied using the fluorogenic substrate 4-methylumbelliferyl-β-D-mannopyranoside. A comparison of the biochemical properties of the CV β-mannosidase with those of the enzyme from human cultured fibroblasts showed their similarity. Like the enzyme from skin fibroblasts, the CV β-mannosidase had rather high activity. Both enzymes had virtually the same pH optimum (4.2-4.7) and K_m value. The data presented suggest that chorion biopsy specimens can be used for prenatal determination of β-mannosidase activity at an early stage of development.     

原油储罐机械化清洗技术的应用

分析了国内原油储罐清洗工艺现状，详细介绍了原油储罐机械化清洗技术及应用，从安全、环保、效益几方面对应用效果做了客观分析，阐述了机械化清洗技术的科学性和优越性。