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31.
A new aromatic alkine was isolated from the tuber of Sparganium stoloniferum . Its structure was assigned to be methyl 3,6-dihydroxy-2-[2-(2-hydroxyphenyl)-ethynyl]benzoate (1) by spectroscopic methods. 相似文献
32.
甲胺基阿维菌素苯甲酸盐对南方根结线虫的毒力、防效及安全性研究 总被引:5,自引:0,他引:5
选用02%高渗甲胺基阿维菌素苯甲酸盐(甲维盐)和18%阿维菌素对南方根结线虫进行室内毒力测定和盆钵药效试验.室内毒力测定结果显示:甲维盐对南方根结线虫二龄幼虫(J2)的毒力高于阿维菌素,甲维盐和阿维菌素的LC50值分别为0164 5、0453 2 mg·L-1.盆钵药效试验结果显示:甲维盐500倍液、1 000倍液对南方根结线虫病的相对防效为9367%、7969%,与阿维菌素防效相当,且甲维盐能显著抑制根结和卵块的产生.安全性测定结果显示:甲维盐各处理浓度对番茄生长均没有不良影响.表明:甲维盐可与阿维菌素交替应用于防治南方根结线虫病. 相似文献
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34.
为明确华北棉区棉铃虫Helicoverpa armigera田间种群对3种常用杀虫剂的抗性,于2014—2015年和2018—2019年分别采集河南、河北、山东和山西4个省的棉铃虫田间种群,采用浸叶法于室内测定棉铃虫对辛硫磷、三氟氯氰菊酯和甲维盐的抗性水平。结果表明,各监测点棉铃虫对辛硫磷处于中等水平抗性,在2014—2015年和2018—2019年的抗性倍数分别为13.0~58.5倍和21.1~55.3倍,棉铃虫对辛硫磷的抗性发展相对缓慢;各监测点棉铃虫种群对三氟氯氰菊酯已产生中等至高水平抗性,并呈现逐年上升的趋势,其中河北沧县、河南安阳、山西盐湖种群的抗性倍数由2014年的61.0倍、22.5倍和24.0倍上升至2019年的91.1倍、44.7倍和61.3倍,山东夏津种群的抗性最高,2019年抗性倍数达到216.3倍;棉铃虫种群对甲维盐表现为低至中等水平抗性,河北沧县、河南安阳、山西盐湖和山东夏津种群的抗性倍数分别为8.2~40.4倍、5.8~16.6倍、5.5~23.4倍和11.0~36.6倍。表明4个监测地区的棉铃虫田间种群对3种杀虫剂已经产生了不同程度的抗性,建议减少这3种杀虫剂的使用频次,并注意与其他杀虫剂交替轮换使用,以延缓棉铃虫抗药性的发展。 相似文献
35.
36.
高效液相色谱法定量分析甲氨基阿维菌素苯甲酸盐 总被引:8,自引:1,他引:8
研究用HPLC定量分析甲维盐的方法。色谱条件如下:150mm×4.6mm不锈钢柱,用Hypersil,C185μm粒径,孔径300A;流动相:甲醇+水=80+20;流速1.0mL/min;紫外检测器波长254nm。本方法在1~8μg进样范围内和峰高呈线性。相关系数值(r)为0.9997。甲维盐分析方法的回收率为99.42%。 相似文献
37.
Min Zhou Lijie Yang Yanhong Chen Tong Sun Nuan Wang Xing Chen Zaibin Yang Jinshan Ge Shuzhen Jiang 《Journal of animal physiology and animal nutrition》2019,103(6):1885-1894
The objective of this study was to evaluate the effects of zearalenone (ZEA) and estradiol benzoate (EB) on stress injury and uterine development in post‐weaning gilts. Thirty healthy post‐weaning female gilts (Duroc × Landrace × Large White) aged 28–32 days were randomly allocated to three treatments as follows: (a) basal diet (Control), (b) basal diet plus 1.0 mg/kg purified ZEA (ZEA) and (c) basal diet plus 0.75 ml (1.5 mg) EB per pig at 3‐days intervals by intramuscular injection (EB). The serum estradiol (E2), the final and the increased vulvar area, uterine index, thickness of the myometrium and endometrium, and protein expression of heat shock protein 70 (HSP70) in ZEA group were higher than those in the control group (p < .05), but lower than those in the EB group (p < .05). The serum luteinizing hormone in ZEA group was lower than that of the control group (p < .05), but higher than that in the EB group (p < .05). Higher serum follicle‐stimulating hormone and progesterone were observed in the ZEA and control groups than those in the EB group (p < .05). The serum glutathione peroxidase activity in the ZEA group was lower than that in the control and EB groups (p < .001), and the malondialdehyde in the ZEA group was higher than that in the control and EB groups (p < .001). Moreover, the relative mRNA and protein expression of growth hormone receptor (GHR) and relative mRNA expression of HSP70 in the ZEA and EB groups were higher than those in the control group (p < .05). In conclusion, both ZEA (1.0 mg/kg) and EB (1.5 mg at 3 days intervals by intramuscular injection) stimulated vulvar swelling and uterine hypertrophy by disordering serum hormones and up‐regulating GHR expression, and induced stress by different mechanisms in this study. Furthermore, the observed up‐regulating HSP70 expression challenged by ZEA or EB may be part of the mechanism to resist stress injury. 相似文献
38.
Jeferson Ferreira da Fonseca Fabiana Nunes Zambrini Jos Domingos Guimares Marcio Roberto Silva Maria Emilia Franco Oliveira Felipe Zandonadi Brando Pawel Mieczyslaw Bartlewski Joanna Maria Gonalves Souza‐Fabjan 《Reproduction in domestic animals》2019,54(1):118-125
This study examined the feasibility of transcervical embryo recovery after the hormonal treatment to induce cervical dilation, following the 7‐day oestrous synchronization protocol in multiparous Santa Inês ewes. A total of 23 cyclic ewes received two doses of 37.5 μg of d‐cloprostenol by latero‐vulvar route 7 days apart. After the second injection of d‐cloprostenol, the ewes were checked for oestrus (every 12 hr) and then mated by fertile rams throughout the oestrous period. All ewes received 37.5 μg of d‐cloprostenol (latero‐vulvar) and 1 mg of oestradiol benzoate by either intramuscular (EBim group; n = 12) or intravaginal (EBivg group; n = 11) route 16 hr before embryo flushing. Twenty minutes before the flushing, 50 IU of oxytocin were administered intravenously. The oestrous response (i.e., the percentage of ewes that showed signs of oestrous behaviour after the second d‐cloprostenol injection) was 91.3% (21/23). The proportion of successfully penetrated ewes (81.8% compared with 80.0%), the mean duration of embryo flushing (24.7 ± 2.0 min compared 26.2 ± 1.9 min), the flushing fluid recovery rate (94.8 ± 1.3% compared with 91.0 ± 2.9%) and the average number of structures recovered per ewe (0.5 ± 0.4 compared with 0.8 ± 0.4) did not vary (p > 0.05) between the EBim and EBivg groups. Viable embryos were recovered from 41.2% (7/17) of successfully penetrated ewes. It can be concluded that nonsurgical (i.e., transcervical) embryo collection can be performed in oestrous‐synchronized Santa Inês ewes pretreated with d‐cloprostenol, oxytocin and oestradiol benzoate, with the latter hormone administered by either the intramuscular or intravaginal route. 相似文献
39.
对羟基苯甲酸与正丁醇分别在浓硫酸、对甲苯磺酸、磷钨酸铯这三种催化剂催化下,探讨了合成对羟基苯甲酸丁酯的利与弊,分析了酯化反应的各种影响因素,以及这几种反应方法的优化反应条件。 相似文献
40.
几种生物药剂防治菜青虫的药效试验 总被引:2,自引:0,他引:2
菜青虫是黑龙江省柳河地区蔬菜最重要的害虫之一,近年来发生呈上升趋势,经常暴发成灾。文章用威克达乳油、农家乐乳油、菜地隆乳油及绿维特水剂等4种无公害药剂在田间对菜青虫幼虫进行了防治试验。结果表明,1%威克达乳油2 000倍液施药1 d后防治效果76.13%,施药后3 d防治效果80.91%,施药后7 d防治效果86.34%。经多重比较分析结果表明,在防治后1、3、7 d,1%威克达防治效果与其他3种药剂比较均有显著差异,具有防治效果好、成本低、无污染等特点,在生产中可以应用。 相似文献