共查询到11条相似文献,搜索用时 46 毫秒
1.
利用泥鳅红细胞微核及核异常测定法对四种除草剂遗传毒性的研究 总被引:11,自引:0,他引:11
采用红细胞微核和核异常测试法,研究了除草剂精禾草克、氟乐灵、扫特、2甲4氯钠盐水剂对泥鳅红细胞的遗传毒性。泥鳅在各除草剂试验液中染毒24h,采血制片。结果表明,四种除草剂均不同程度地引起微核细胞率和核异常细胞率等遗传指标的上升,其中部分浓度组较对照组差异显著(P<0.05)或极显著(P<0.01)。除草剂浓度与微核率或核异常率无显著相关,不表现剂量效应关系。四种除草剂对泥鳅红细胞具有明显的诱变效应,其中扫特的诱变效应大于其它三种除草剂。 相似文献
2.
本文着重介绍杜邦公司开发的超高效,高选择性、广谱性和芽后处理的磺酰脲类除草剂的历史发展,以及国内研究的合成路线。 相似文献
3.
4.
我国农田杂草危害严重,粮棉损失惊人。据调查,全国农田杂草造成危害的有225种,严重危害的有31种,危害严重且难以防治的有17种,受害作物面积达6亿多亩,占全国播种面积的22%;各种作物的平均损失13.4%,其中年损失粮食175亿公斤,棉花500万担,油莱、花生2亿公斤。看来草“口”夺粮,巳是当务之急。 发达国家对化学除草剂的发展十分重视,80年代化学除草剂产量、销售量、销售额均占农药总产量的40—50%,在农药生产中,除草剂和杀虫剂的比例为4—5:1。而我国恰好相反,除草剂和杀虫剂之比仅为 相似文献
5.
6.
7.
杂草对磺酰脲类除草剂的抗性 总被引:4,自引:0,他引:4
磺酰脲类除草剂由于用量低、低毒、广谱及使用方便而广泛、迅速的用于各种作物,然而在使用中,杂草抗性迅速发展而成为非常重要的问题,从而最终减少其使用。笔者综述了磺酰脲类除草剂杂草抗性现状、抗性机制及延迟抗性的措施。 相似文献
8.
9.
综述了砜嘧磺隆的理化性质、作用方式、毒理学与环境生态安全性,介绍了该除草剂的合成化学及其应用研究与开发进展。 相似文献
10.
11.
Traditionally, CD has been used extensively for peptides insecondary structure analysis. In recent years, NMR chemicalshifts and nuclear Overhauser enhancements have been widelyused in conjunction with CD to assess the secondary structuresof peptides and proteins; however, there are many instanceswhere the estimation of secondary structure contents differssignificantly between the two methods. In order to elucidatethe perceived differences between the two methods, secondarystructure estimations by CD and 1H NMR chemical shifts werecompared for over 50 peptides. The linear peptides investigatedwere largely unstructured, {small tilde}1550 residuesin size, and lacked stable tertiary conformation. These peptideswere studied in different solvent systems including water, alcoholwater,micelles and urea. A strong correlation exists for secondarystructure assessment by CD and NMR chemical shifts; however,an interesting trend of higher estimation of helical contentsby NMR was observed for peptide fragments from globular proteinsstudied in water. This may be a result of associative propertiesof these peptides in water. Addition-ally, a new method of quantitatingsecondary structure contents based on 1H NMR chemical shiftsis reported. 相似文献