浅谈苄·二氯对抛栽水稻的药害及预防措施

针对当前兴业县高峰镇抛秧田应用面积最广的除草剂苄·二氯因使用不当造成水稻药害的现状,进行深入的调查研究,找出造成药害的原因,提出切实可行的预防措施。     

青蒿素与二甲氧苄啶联合抗鸡球虫的试验研究

为研究青蒿素(ART)与二甲氧苄啶(DVD)联合应用抗鸡球虫的效果,选用75只黄羽肉鸡,分为5个组,除阴性对照组外,ART组、DVD组、ART+DVD组和阳性对照组经嗉囊接种8×10~4个柔嫩艾美耳球虫孢子化卵囊,各组在攻虫前一天用药直至试验结束,观察鸡群发病和死亡情况,记录相对增重率、存活率、卵囊值、病变记分、血便数,计算抗球虫指数(ACI)。血便数结果显示,ART+DVD组高于DVD组,低于ART组和阳性对照组;存活率、病变记分、平均增重等结果显示,ART+DVD组低于DVD组,高于ART组。结果表明,ART单独使用时具有一定的抗球虫效果,但将其与抗菌增效剂联用则不仅能增强抗球虫效果,更可减少DVD的用药量,从而降低了DVD残留的可能性。     

气相色谱-质谱联用测定奶牛血清中的β-羟丁酸

为了建立测定奶牛血清中代谢产物β-羟丁酸含量的气相色谱-质谱联用方法,为奶牛酮病的早期诊断提供新途径。将奶牛血清样品用甲醇除蛋白,上清液经氮气吹干,残渣进行硅烷化衍生后,用GC-MS仪全扫描方式进行检测。结果测定血清中β-羟丁酸的线性范围为0.05 mmol/L~8 mmol/L,相关系数R=0.9995,检测限为0.03 mmol/L,定量限为0.05mmol/L,相对标准偏差RSD=5.79%,样品加标回收率为95.10%~99.91%。表明该方法能简便、快速、有效地分离并定量检测血清中的β-羟丁酸,可以作为奶牛酮病的早期诊断依据。     

35%禾·苄可湿性粉剂不同施药期不同用药量药效试验

在筛选出适合湖州地区直播稻田杂草防除药剂禾·苄可湿性粉剂的基础上,对禾·苄可湿性粉剂的不同施药期和不同用药量进行了应用技术研究,结果表明,以每667 m~2用有效成分3 5%禾·苄可湿性粉剂50～75g+10%苄嘧磺隆2～2,4 g为宜,施药适期为水稻立针期～2叶1心期(即种谷播后4～10 d)。     

Insecticidal Constructure and Bioactivities of Compounds from Ficus sarmentosa var. henryi

Insecticidal activities of the petroleum ether-, chloroform-, ethyl acetate-, and water-soluble fractions of the methanolic extract of Ficus sarmentosa var. henryi were assayed against Musca domestica adults. The chloroform- and ethyl acetate-soluble fractions were the most active with 92.6 and 88.9% mortalities (24 h after treatment) respectively. Therefore, the two fractions were combined and four compounds, isolated from the fractions by activity-guided fractionation, were elucidated as 7-hydroxycoumarin, apigenin, eriodictyol, and quercetin by spectroscopic method and displayed excellent insecticidal activities against adults of M. domestica and 4th instar larva of Aedes albopictus. Among those, 7-hydroxycoumarin showed the strongest insecticidal activities with lethal concentrations (LC₅₀) values of 72.13 μg g⁻¹ sugar and 4.87 μg mL⁻¹ (48 h after treatment) against the test insects respectively. The cytoxicities of these compounds on BTI-Tn-5Bl-4 cell were also investigated for the insecticidal mechanism and found that quercetin represented superior inhibitory activity with MTT assay and reactive oxygen species (ROS) against BTI-Tn-5Bl-4 cell, but slightly weaker than that of the positive control (azadirachtin) and significantly greater than the negative control (DMSO only). Meanwhile, eriodictyol demonstrated the strongest effect on the mitochondrial membrane potentials (MMP). In conclusion, based on their comparative toxicities to commercial insecticides and their cytotoxic effects, some of the compounds from the F. sarmentosa have potential as botanical insecticides.     

翠菊花叶多糖对羟自由基的清除作用

在对翠菊花、叶多糖提取分离纯化的基础上,采用邻二氮菲-Fe2+氧化法研究了翠菊花、叶多糖对羟自由基的清除作用.结果表明,翠菊花、叶多糖均对羟自由基有清除作用,翠菊花、叶多糖溶液浓度与羟自由基清除率呈极显著正相关.当羟自由基清除率为10％时所需翠菊花、叶多糖溶液浓度分别为0.058 3、0.003 5 mg/mL,翠菊叶多糖对羟自由基清除能力相对较强.     

DHP及其核受体诱导斑马鱼促性腺激素释放激素mRNA表达

为了明确17α,20β双羟孕酮(DHP)及其核受体调控促性腺激素释放激素mRNA在雄性斑马鱼脑组织中的表达机制,采用实时荧光定量PCR方法、类固醇激素活体和离体暴露方法进行试验。结果表明,野生型雄性斑马鱼活体暴露于100 nmol/L DHP水溶液,伴随暴露时间的延长,gnrh2和gnrh3 mRNA表达量呈逐渐升高趋势,24 h出现表达最高峰;野生型雄性斑马鱼活体分别暴露于10和100 nmol/L DHP水溶液24 h。与对照组相比,100 nmol/L DHP试验组gnrh2和gnrh3 mRNA表达量升高,差异显著(P<0.05),而10 nmol/L DHP试验组无显著变化(P>0.05);野生型雄性斑马鱼活体暴露于100 nmol/L DHP与100 nmol/L RU486混合水溶液24 h,试验组gnrh2和gnrh3 mRNA表达量与对照组相比无显著变化(P>0.05);野生型和孕酮核受体敲除型(pgr~(-/-))雄性斑马鱼活体分别暴露于100 nmol/L DHP水溶液24 h,与野生型试验组相比pgr~(-/-)型试验组gnrh2和gnrh3 mRNA表达量显著降低(P<0.05);野生型和pgr~(-/-)型雄性斑马鱼脑组织离体暴露于含100 nmol/L DHP的L-15培养液24 h,与野生型试验组相比pgr~(-/-)型试验组gnrh2和gnrh3 mRNA表达量显著降低(P<0.05)。由此可见,DHP与核受体结合可直接调控雄性斑马鱼脑组织中促性腺激素释放激素gnrh2和gnrh3 mRNA表达。     

金属硫蛋白生物学功能研究进展

本文综合相关文献，对金属硫蛋白的生物学功能研究进展进行了归纳和总结。提出了在研究工作中需要注意的问题。     

家禽常见药物新用法、用量介绍

<正>1青霉素类1.1青霉素G,又名青霉素、苄青霉素。肌注:5~10万国际单位/千克体重。与四环素等酸性药物及磺胺类药有配伍禁忌。1.2氨苄青霉素,又名氨苄西林、氨比西林。拌料:0.02%~0.05%;肌注:25~40毫克/千克体重。1.3阿莫西林,又名羟氨苄青霉素。饮水或拌料:0.02%~0.05%。     

丁基罗丹明B-Fe~(2+)-H_2O_2体系光度法测定蔬菜的抗氧化活性

研究了测定蔬菜抗氧化活性的分光光度法,用该方法测定了10种蔬菜提取液对羟自由基的清除率,结果表明,香菜、菠菜的抗氧化活性较强。