新加坡高等教育改革新动向述评

面对知识经济的发展和亚洲各国的挑战,尤其是中国经济崛起所带来的变化,新加坡政府实施了一系列新的高等教育改革措施,其内容主要包括"大学自主"运动、"环球校园"计划等.这些改革措施,对我国当前的教育改革有较大的启示和借鉴作用.     

土壤湿度对东亚小花蝽越冬存活率的影响

１９９１～１９９３年在北京对东亚小花蝽的越冬进行了研究。结果表明：东亚小花蝽以交配或未交配的雌成虫越冬。越冬场所的土壤湿度影响小花蝽的存活率。３月中旬检查，室外自然条件下，越冬存活率为７．７４％。在控制土壤含水量（４％、１２％和２０％）的条件下，越冬存活率随土壤水分的增加而递增，水分２０％时存活率最高，平均为８１．１１％。３月中旬气温回升后将越冬小花蝽雌成虫移入７℃的冰箱，贮存至５月上旬，存活率为５５％，而自然条件下小花蝽已全部死亡     

Evidence for the transmission of scrapie to sheep and goats from a vaccine against Mycoplasma agalactiae

An accidental infection from a vaccine was suggested as the explanation for the sudden increase in outbreaks of scrapie in Italy in 1997 and 1998. This paper describes a recent outbreak of scrapie in sheep and goats which were exposed to the same vaccine. No ewes or goats had been imported into the herd since 1992, but a vaccine against Mycoplasma agalactiae had been administered twice, in 1995 and 1997. High rates of crude mortality and scrapie incidence were experienced by both species, all birth cohorts were involved and a large proportion of aged animals was affected. A pattern of brain lesions was observed, with slight differences between the sheep and goats, which was very similar to the pattern observed in animals previously exposed to the same vaccine but clearly different from that observed in the brains of sheep with scrapie in a flock not exposed to the vaccine. Regardless of their exposure status, genotype analysis of the sheep showed the presence of polymorphism only at codon 171. The patterns of both incidence and brain lesions provide evidence that the epidemic of scrapie was due to the use of the vaccine.     

桑黄子实体多糖提取条件的研究

通过单因子试验和正交试验，研究了桑黄（Phellinus igniarius）子实体多糖的提取条件。结果表明，热水浸提法提取桑黄子实体多糖的最佳条件为料水比1：30（W：V）。提取温度90℃，提取时间3h，乙醇终浓度80％。同时采用超声波法提取桑黄子实体多糖，其多糖得率为4．65％。     

重金属镉污染对蔬菜的影响及防治对策

从蔬菜中镉的来源、含量和蔬菜对重金属镉的累积特点,提出了镉污染蔬菜的防治对策,指出应根据不同程度土壤镉污染的状况,密切配合各项农艺措施的实施来种植不同品种的蔬菜.     

蜂胶的免疫增强作用及其在疫苗中的应用

蜂胶极其复杂的化学成分，决定了它具有广泛的生物学作用。其中，蜂胶具有抗菌、抗病毒及增强机体免疫功能等作用；蜂胶颗粒能与抗原相互交联成类免疫刺激复合物（ISCOM）结构，具有抗原“仓库”和免疫刺激复合物作用；蜂胶本身没有抗原性，但可起到免疫佐剂的作用，促进抗体的生成；这些作用及其间的协同作用决定了蜂胶是一种天然的免疫增强剂。自20世纪60年代以来，蜂胶的免疫增强作用及其在疫苗佐剂中的研究不断深入，并取得了满意效果,这为新型而有效疫苗的研制和开发提供一些理论指导。     

旱直播稻田杂草发生规律及防除技术研究

江苏省淮安市旱直播水稻田由于前期以湿润管理为主，故早生杂草与湿生杂草混生，草相复杂，草害严重。用36％丁恶EC150ml/667m^2、30％扫荛特EC100ml/667m^2＋10％苄磺隆WP20g/667m^2、55％义星秧清WP45g/667m^2，对单双子叶杂草均有很好的防除效果。     

老岭自然保护区野菜资源调查研究

老岭自然保护区野菜资源十分丰富，经过调查研究，共有136种，隶属47科，95属。按食用部位和器官对其进行了分类，并对野菜资源的开发利用进行了探讨。