四氯化碳中毒对大鼠离体再生肝细胞钾离子外漏的影响

本工作用三种剂量四氯化碳(CCl_4,10,15和20mmol/L)损伤正常大鼠离体肝细胞,分别在5,10,15和20min测定细胞内K~+和GPT漏出量。实验观察到细胞内K~+和GPT漏出量与CCl_4染毒的剂量和时间有明显关系,而且K~+漏出量较GPT更能灵敏地反映细胞的损伤程度;用中等剂量CCl_4(15mmol/L)损伤离体再生肝细胞20min后,细胞内K~+漏出的变化百分数明显低于正常肝细胞。这些结果表明,大鼠离体再生肝细胞具有较强的抗CCl_4损伤作用,其机制可能与再生肝细胞膜稳定性较强有关。     

拟除虫菊酯的结构与害虫抗药性的关系

以家蝇Musca domestica vicina L.为试虫,用汰选方法研究了家蝇对六种不同拟除虫菊酯的抗性发展.结果表明,家蝇对不同化学结构和不同光学异构体组分的拟除虫菊酯抗性差别很大.对溴氧菊酯、顺式氯氰菊酯抗性发展很快,氯氰菊酯次之,氰戊菊酯、氰戍菊酯A和氰戊菊酯A_σ抗性发展较慢.用抗溴氰菊酯家蝇品系和点滴法测定了十种拟除虫菊酯和七种有机磷杀虫剂的毒力,讨论了它们之间的交互抗性和结构与抗性的关系.溴氰菊酯(抗性比值24.00)、氯氰嫡酯(抗性比值20.11)、顺式氯氰菊酯(抗性比值38.10)和二氯苯醚菊酯(抗性比值11.04),结构相近的交互抗性比较严重.氰戊菊酯(抗性比值4.64)、氰戊菊酯A(抗性比值5.97)、戊菊酯(抗性比值4.49)和氟氰菊酯(抗性比值4.12)化学结构中醇部分与溴氰菊酯相同、酸部分不同,它们与溴氰菊酯交互抗性水平较低.联苯菊酯(抗性比值1.98)化学结构中酯和醇部分都与溴氰菊酯不同,其交互抗性水平较低,杀螟松等七种有机磷杀虫剂,除敌敌畏与溴氰菊酯有轻微交互坑性外,其它均无交互抗性.     

蝇蛹俑小蜂、丽蝇蛹集金小蜂触角感器的扫描电镜观察

本文利用扫描电镜首次对蝇蛹俑小蜂(Spalangia endius)触角及其感器进行了研究.共观察到七类感器:触觉毛类感器、板状感器、薄壁化学感受器、锥形乳头状感器、鬃形感器、短刺形感器和棒状感器.同时在丽蝇蛹集金小蜂(Nasonia Vitripennis)触角上观察到七种感器.比较研究发现,在两种小蜂间.同种小蜂异性间.感器的种类、数量、排列及分布均有差异,并对此进行了讨论.     

A homologue of the Escherichia coli DsbA protein involved in disulphide bond formation is required for enterotoxin biogenesis in Vibrio cholerae

A strain of Vibrio cholerae, which had been engineered to express high levels of the non-toxic B subunit (EtxB) of Escherichia coli heat-labile enterotoxin, was subjected to transposon (TnphoA) mutagenesis. Two chromosomal TnphoA insertion mutations of the strain were isolated that showed a severe defect in the amount of EtxB produced. The loci disrupted by TnphoA in the two mutant derivatives were cloned and sequenced, and this revealed that the transposon had inserted at different sites in the same gene. The open reading frame of the gene predicts a 200-amino-acid exported protein, with a Cys-X-X-Cys motif characteristic of thioredoxin, protein disulphide isomerase, and DsbA (a periplasmic protein required for disulphide bond formation in E. coli). The V. cholerae protein exhibited 40% identity with the DsbA protein of E. coli, including 90% identity in the region of the active-site motif. Introduction of a plasmid encoding E. coli DsbA into the V. cholerae TnphoA derivatives was found to restore enterotoxin formation, whilst expression of Etx or EtxB in a dsbA mutant of E. coli confirmed that DsbA is required for enterotoxin formation in E. coli. These results suggest that, since each EtxB subunit contains a single intramolecular disulphide bond, a transient intermolecular interaction with DsbA occurs during toxin subunit folding which catalyses formation of the disulphide in vivo.     

中国巨腿花螳属二新种记述：螳螂目：花螳螂亚科

本文记述花螳螂亚科巨腿花螳属二新种:半黑巨腿花螳 Hestiasula seminigra Zhang sp.nov.基黑巨腿花螳H.basinigra Zhang sp.nov.模式标本保存于南京林业大学昆虫标本室。     

四川鱼类寄生吸虫一新种：（复殖目：尾孔科）

本文记述了尾孔科吸虫一新种——平睾尾孔吸虫,新种Urotrema parallelorchis sp.nov.。新种采自短身间吸鳅和犁头鳅的肠道。新种的睾丸左右排列而不同于该属的所有已知种。     

亚洲象无齿奎隆线虫一新种：（圆形亚目：毛线科）

本文报道作者近年来在石家庄动物园对亚洲象Elephas maximus进行药物驱虫时采集的寄生线虫一新种,无齿奎隆线虫,新种Quilonia edentata sp.nov.,模式标本保存于河北师范大学生物系。     

高翔蜉属一新种：蜉蝣目：扁蜉蝣科

本文记述采自湖南省大庸市高翔蜉属一新种。该种以其阳茎叶外侧面具有一向前弯曲的钩状突起为显著特征,可区别于本属其他种类。     

活性氧对巨噬细胞呼吸爆发影响及云芝多糖的保护作用

用化学发光法观察到叔丁基氢过氧化物对培养的小鼠腹腔巨噬细胞呼吸爆发有强烈的抑制作用。云芝多糖经腹腔注射后,能增强巨噬细胞呼吸爆发功能对叔丁基氢过氧化物损伤的抵抗力。云芝多糖处理的巨噬细胞谷胱甘肽过氧化物酶基础活力显著提高,在叔丁基氢过氧化物作用下,云芝多糖处理的巨噬细胞仍有较高的谷胱甘肽过氧化物酶活力。说明巨噬细胞的免疫功能与谷胱甘肽过氧化物酶活力有关,非特异性免疫多糖可提高细胞抗氧化能力,减轻活性氧损伤作用。