甲醇汽油的毒性分析及应用要求

甲醇汽油中的原料甲醇主要来源于煤化工和天然气提纯过程,合理发展甲醇汽油,利用甲醇的巨大产能,适合我国以煤为主的能源结构的国情,也符合我国大力发展天然气发电及城镇燃气供应的规划。低比例甲醇汽油的毒性属于轻微,在生产使用过程中,只要遵守操作规程,做好防护,出现大剂量误服、皮肤接触和环境浓度过大导致急性中毒的可能性很小,安全有保证。     

Developmental characteristics and response to iron toxicity of root border cells in rice seedlings

To investigate the Fe2 effects on root tips in rice plant, experiments were carded out using border cells in vitro. The border cells were pre-planted in aeroponic culture and detached from root tips. Most border cells have a long elliptical shape. The number and the viability of border cells in situ reached the maxima of 1600 and 97.5%, respectively, at 20～25 mm root length. This mortality was more pronounced at the first 1～12 h exposure to 250 mg/L Fe2 than at the last 12～36 h. After 36 h, the cell viability exposed to 250 mg/L Fe2 decreased to nought, whereas it was 46.5% at 0 mg/L Fe2 . Increased Fe2 dosage stimulated the death of detached border cells from rice cultivars. After 4 h Fe2 treatment, the cell viabilities were≥80% at 0 and 50 mg/L Fe2 treatment and were <62% at 150, 250 and 350 mg/L Fe2 treatment; The viability of border cells decreased by 10% when the Fe2 concentration increased by 100 mg/L. After 24 h Fe2 treatment, the viabilities of border cells at all the Fe2 levels were <65%; The viability of border cells decreased by 20% when the Fe2 concentration increased by 100 mg/L. The decreased viabilities of border cells indicated that Fe2 dosage and treatment time would cause deadly effect on the border cells. The increased cell death could protect the root tips from toxic harm. Therefore, it may protect root from the damage caused by harmful iron toxicity.     

多氯联苯对环境的污染和对动物及人体的危害

本介绍了多氯联苯对环境的污染，对动物和人的毒性作用及潜在致癌性的研究进展。     

废旧干电池对泥鳅的毒性效应

以抗污染能力强的泥鳅(Misgurnus anguillicadatus)为实验材料,研究了废旧干电池污染的水源对水生生物具有极强的毒害作用.结果表明,泥鳅受毒害程度与水体中废旧干电池的数量和暴露时间成正相关关系;对受毒害但未死亡的个体断尾取血,显微镜下观察血红细胞的形态、结构,发现在废旧干电池污染的水体中残存的个体,其血红细胞的变异率远远超过生活在正常水体中的个体.     

60例老年住院病人用药分析

老年人由于内脏功能减退，免疫功能差，易患多种疾病，另一方面，老年病人的药物分布，代谢、清除等因年龄增加而衰退，本文分析了老年病人临床治疗用药方面的特殊性，并就其多种药物并用的原因和对策进行了讨论，老年人药物治疗应严格地掌握适应症。对有合并症患者的用药尤需谨慎，尤其是搭配及混合用药方面，应考虑避免或减少药物毒性作用的产生。     

The performance of adverse effects search filters in MEDLINE and EMBASE

Background: Search filters can potentially improve the efficiency of searches involving electronic databases such as medline and embase . Although search filters have been developed for identifying records that contain adverse effects data, little is known about the sensitivity of such filters. Objectives: This study measured the sensitivity of using available adverse effects filters to retrieve papers with adverse effects data. Methods: A total of 233 included studies from 26 systematic reviews of adverse effects were used for analysis. Search filters from medline and embase were tested for their sensitivity in retrieving the records included in these reviews. In addition, the sensitivity of each individual search term used in at least one search filter was measured. Results: Subheadings proved the most useful search terms in both medline and embase . No indexing terms in medline achieved over 12% sensitivity. The sensitivity of published search filters varied in medline from 3% to 93% and in embase from 57% to 97%. Whether this level of sensitivity is acceptable will be dependent on the purpose of the search. Conclusions: Although no adverse effects search filter captured all the relevant records, high sensitivity could be achieved. Search filters may therefore be useful in retrieving adverse effects data.