Initial Homotypic Cell Pair Adhesion in Regenerating Hydra Facilitates Subsequent Adhesion of Homotypic Cells

 In Hydra vulgaris at the level of dissociated single cells endodermal cells adhere to each other more readily than to ectodermal cells at the initial adhesion. The time required for adhesion to occur between two adjacent cells is shorter for both endodermal and ectodermal homotypic cell adhesions once the initial adhesion of the first pair of cells has been established. It is confirmed that contact of an aggregated pair with additional homotypic cells facilitates the occurrence of homotypic adhesions; heterotypic adhesions are discouraged. This suggests that adhesion of homotypic cells contributes to an increased readiness for subsequent homotypic cells to adhere. Received: 25 August 1999 / Accepted in revised form: 11 January 2000     

用硫酸烧渣法处理煤系硫铁矿

本文提出一种以废治无污染的处理煤系硫铁矿的工艺。该工艺利用硫酸生产过程中所产生的废渣中的氧化铁，经处理后在硫酸介质中与硫铁矿反应，使硫铁矿中的硫和铁及烧渣中的铁资源得到充分的回收利用，既有利于环境保护，又具有良好的经济效益。     

Prenatal diagnosis in two cases of de novo complex balanced chromosomal rearrangements. Three-year follow-up in one case

We report two cases of apparently balanced complex de novo chromosomal rearrangements (BCCR) detected prenatally at 17 weeks and 10 weeks of gestation, respectively. Chromosomes were studied using GTG-banding and fluorescent in situ hybridization (FISH). In one case four chromosomes and in the other case three chromosomes were involved in the rearrangements. One of the pregnancies was terminated and no external or internal abnormalities were detected at autopsy. The other pregnancy continued to term. Level III ultrasound examination showed no abnormalities. The child is now 3 years old and has neither congenital anomalies nor evidence of delayed psychomotor development.     

Prenatal diagnosis of β thalassaemia by reverse phase HPLC

Reverse phase HPLC of radioactive globin chains has been compared to classical carboxy methyl cellulose chromatography for the prenatal diagnosis of β thalassaemia. The two methods correlated highly (r = 0.97 p < 0.0005) and provided an identical diagnosis for 40 fetal blood samples of fetuses homozygous or heterozygous for β thalassaemia. The HPLC procedure was much faster and required fewer biochemical steps (no globin preparation). It was at least as accurate and more sensitive than the classical chromatography. A single column can be used for 150 analyses and is always ready to be used. Last but not least it is much less expensive than CMC chromatography.     

浅析环境统计工作中存在的问题及改进方法

针对环境统计存在的问题，分析产生的原因，并提出解决环境统计工作问题的方法。     

炼油厂废碱液治理技术的研究

针对炼油厂废碱液存在的问题，研究一种新处理技术—溶剂萃取、破乳和臭氧氧化。为了解不同水质、ｐＨ值、温度的影响而进行试验研究，并获得了最佳操作参数。试验结果表明该技术在脱酚、除油、脱色脱臭方面是一种有效方法。     

大使的环保情节--访挪威驻华大使赫图安先生

赫图安(Tor Chr．Hildan)大使似乎与本杂志有缘，在他刚刚接到出任驻华大使任书的同时．也接到了本刊通过挪威驻华使馆文化专员梅园梅(Rigmor Kristin Johnsen)女士转达的采访邀请．他欣然接受了本刊的采访邀请，原意把本刊作为他来华后首先接受采访的媒体．并希望能为《世界环境》提供支持。     

城市户外热环境的舒适性研究

介绍了户外热环境舒适性评价的几种方法，提出了户外热环境舒适评价指标OTCD，指出了在室内OTCD能与PMV很好吻合，并且OTCD的各项参数便于测量。