类保幼激素对三带喙库蚊滞育发生与解除作用的研究

蚊虫的滞育与激素的调节有关,本文探讨类保幼激素(S-31183)对三带喙库蚊滞育发生与解除的作用。实验室用S-31183分別处理三带喙库蚊幼虫与成虫的结果表明,幼虫期接触类保幼激素对成虫期滞育的发生无影响;小新羽化成蚊吸入或点滴处理一定量的类保幼激素后,短光照基本不能诱导其发生滞育;而滞育蚊吸入或点滴一定量的S-31183后,可解除其滞育。经类保幼激素处理,还能提高滞育蚊的吸血率。     

微小按蚊长期接触低剂量溴氰菊酯后生理活动和繁殖特性的动态观察

用强迫接触法对微小按蚊进行选育,溴氰菊酯浓度为0.1mg/m~2,选育温度26℃,触药24h后的死亡率至少不低于20%。在选育过程中,对选育蚊的生理活动、繁殖特性等进行动态观察。该蚊长期接触低剂量溴氰菊酯后,并不影响其体重,吸血及寿命:但随选育代数的增加,产卵量减少,孵化率下降,致死力增加。成蚊前期历期时间延长,净增殖力、内禀增长力、增殖有限速率都有所下降。这些因素都可影响后代成活蚊的种群繁殖力。     

山东省济宁市某县白纹伊蚊对常用化学杀虫剂的抗药性

【目的】了解2017年济宁市某县登革热疫情后,白纹伊蚊幼虫及成蚊对几种常用杀虫剂的抗药性水平,为科学合理使用杀虫剂提供数据支撑。【方法】幼虫测定采用浸液法,成蚊测定采用接触筒法。采集的白纹伊蚊幼虫在实验室饲养繁殖1代后,取三龄末四龄初幼虫以及羽化3～5 d未吸血雌蚊作为测试蚊虫,分别测定幼虫及成蚊的抗药性水平并判断抗药性程度。【结果】2018年济宁市某县主要使用氯菊酯、高效氯氟氰菊酯、cis-氯氰菊酯等拟除虫菊酯类和辛硫磷等有机磷类杀虫剂。白纹伊蚊幼虫对双硫磷、溴氰菊酯、氯菊酯、高效氯氰菊酯4种常见杀虫剂的LC_(50)值分别为0.006、0.021、0.209、0.016 mg/L,抗药性倍数分别为3.75、52.50、104.50和17.78倍;另外,对双硫磷低抗,对高效氯氰菊酯中抗,对溴氰菊酯和氯菊酯高抗。成蚊对氯菊酯敏感,击倒率为97.62%,死亡率为100%;对残杀威和马拉硫磷可能抗药性,击倒率分别为97.06%和91.89%,死亡率分别是97.06%和93.24%;对溴氰菊酯、cis-氯氰菊酯、高效氯氟氰菊酯、高效氯氰菊酯为抗药性,击倒率分别是88.00%、95.31%、91.04%、97.10%,死亡率均小于80.00%。【结论】济宁市某县白纹伊蚊幼虫、成蚊对常用杀虫剂已产生不同程度的抗药性,应定期监测白纹伊蚊对杀虫剂的抗药性,科学合理地使用杀虫剂,延缓抗药性产生。     

增效醚与溴氰菊酯混配浸泡蚊帐对疟疾媒介按蚊残效的观察

目的观察比较用增效醚与溴氰菊酯（1：1）混配浸泡蚊帐和单一溴氰菊酯浸泡蚊帐对中华按蚊、嗜人按蚊的滞效.方法采用WHO推荐的接触筒强迫接触法.结果2种不同质地蚊帐浸泡药物6个月后,混配剂型浸药蚊帐跟单一溴氰菊酯浸药蚊帐相比,对2种媒介按蚊的残效均较好,经统计学处理差异无统计学意义（P值均＞0.05）,24 h恢复后中华按蚊和嗜人按蚊的死亡率仍达100%.结论在疟疾流行季节用混配剂型浸泡蚊帐能够对媒介按蚊起到防制作用.     

保幼激素与光照对三带喙库蚊滞育发生与解除作用的研究

本文报告了经保幼激素（ＪＨＩ）处理对三带喙库蚊滞育发生与解除的影响。结果表明，用保幼激素吸入或点滴处理新羽化成蚊，对短光照诱导其发生滞育具有一定的抑制作用，而滞育蚊经吸入或点滴一定量的ＪＨＩ后，可以解除其滞育，解除率与用量有关。此外，ＪＨＩ处理滞育蚊亦可提高其吸血率。     

贵阳市白纹伊蚊对常用杀虫剂的抗性研究

目的了解2016年贵阳市白纹伊蚊幼虫及成蚊对4种常用杀虫剂的抗药性,为当地白纹伊蚊的防控及相关传染病疫情处理提供理论依据。方法广泛采集贵阳市不同区域的白纹伊蚊,并标记采集地点,记录采集试虫数量、虫态等信息。采用WHO推荐的蚊虫抗药性生物测定方法,幼虫采用浸渍法,成虫采用接触筒法,分别测定幼虫和成虫的抗药性,判断抗性程度。参考品系数据引用中国疾病预防控制中心传染病预防控制所的实验结果。结果高效氯氰菊酯、溴氰菊酯、氯菊酯和敌敌畏4种常用杀虫剂对贵阳市白纹伊蚊幼虫的LC50分别为0.006、0.000 7、0.003和0.074 mg/L,为参考品系的7.78、1.8、17.8和2.17倍。成蚊接触0.1%溴氰菊酯药膜1 h后,24 h的死亡率为79.6%,表明成蚊对溴氰菊酯已经产生了抗性;而对3%高效氯氰菊酯、3%氯菊酯、0.06%残杀威和8%顺式氯氰菊酯药膜接触1 h后,24 h死亡率分别为93.2%、90%、87.9%和97.4%,均表现为可疑抗性。结论贵阳市白纹伊蚊幼虫对测试的4种杀虫剂均产生了不同程度的抗药性,其中,除了对氯菊酯为中抗外,对高效氯氰菊酯、溴氰菊酯和敌敌畏均为低抗;成蚊对溴氰菊酯产生了抗性,对高效氯氰菊酯等抗性程度需进一步确定,应加强贵州省蚊虫抗药性监测,科学指导杀虫剂的使用。     

按蚊对5种常用杀虫剂的抗药性现场调查研究

目的调查大连市媒介按蚊成蚊对DDT、溴氰菊酯、残杀威、高效氯氰菊酯、氯菊酯抗药性,为合理使用杀虫剂提供科学依据。方法采用WHO成蚊滤纸接触筒法,观察区分剂量开始击倒时间、不同时间击倒率和24h死亡率,根据死亡率判定抗性级别。结果大连市媒介按蚊成蚊对DDT、溴氰菊酯、残杀威、高效氯氰菊酯、氯菊酯首只蚊虫击倒时间分别为6,61、4、8、8min。区分剂量24h死亡率：依次为溴氰菊酯91．30％、残杀威89．48％、氯菊酯84．93％、高效氯氰菊酯80．43％为初步抗性群体（M）;DDT50．60％为抗性群体（R）。结论应加强媒介按蚊抗药性监测,并根据具体情况,采用适宜防蚊方法,合理地使用杀虫剂,预防或减缓媒介按蚊对杀虫剂抗药性的产生和发展。     

江汉平原部分地区媒介按蚊对溴氰菊酯抗性监测分析

目的了解媒介按蚊对溴氰菊酯抗性,为合理使用杀虫剂提供科学依据。方法采用WHO成蚊滤纸接触法,观察首只蚊虫击倒时间、击倒率和死亡率,以区分剂量判定抗性级别,以开始击倒时间和击倒率评估Kdr抗性。结果江汉平原区媒介按蚊首只被溴氰菊酯击倒时间为6～25 min,接触60 min击倒率为1.00%～9.62%,KT50为1 003.5～24 099.78 min,抗性指数4.41～105.79,观察24 h死亡率为2.00%～8.65%,为高抗性群体。结论江汉平原按蚊对溴氰菊酯已产生高度抗性,应交替使用不同类型卫生杀虫剂,确保防治效果,延缓蚊虫抗性升级。     

上海市嘉定区白纹伊蚊对溴氰菊酯和高效氯氰菊酯的抗性测定

目的了解嘉定区白纹伊蚊对溴氰菊酯及高效氯氰菊酯的抗性水平,为制定有效的防蚊策略提供参考。方法采用幼虫浸渍法及接触筒法测定白纹伊蚊幼虫及成蚊对溴氰菊酯及高效氯氰菊酯的抗性水平。结果嘉定区白纹伊蚊幼虫对溴氰菊酯和高效氯氰菊酯均表现出中等抗药性,抗性倍数分别为14.25和13.67。嘉定区白纹伊蚊成蚊对溴氰菊酯和高效氯氰菊酯表现为抗性种群。结论嘉定区白纹伊蚊幼虫及成蚊对溴氰菊酯和高效氯氰菊酯均已产生不同程度的抗性,应加强对菊酯类杀虫剂抗药性的监测,并在化学灭蚊时注意科学合理地轮换用药。     

中华按蚊实验室品系对杀虫剂的敏感性测定

目的 研究实验室品系中华按蚊成蚊及幼虫对常用杀虫剂的敏感性,为中华按蚊的抗药性测定和比较提供参考品系.方法 测定成蚊抗药性水平参考WHO对按蚊的诊断剂量使用接触筒法;测定幼虫对双硫磷、溴氰菊酯、高效氯氰菊酯、氯菊酯、多杀菌素、呋虫胺的半数致死浓度(LC50)及其95％置信限(95％CI)使用WHO推荐的浸渍法.结果 中华按蚊成蚊对4％DDT(1 h)死亡率为56.5％;对0.05％溴氰菊酯(1 h)、0.05％高效氯氰菊酯(1 h)和0.75％氯菊酯(1 h)死亡率均为100％,对0.025％溴氰菊酯(1 h)、0.025％高效氯氰菊酯(1 h)和0.25％氯菊酯(1 h)死亡率分别为100％、99.6％和100％;中华按蚊幼虫对溴氰菊酯、高效氯氰菊酯、氯菊酯、双硫磷、多杀菌素、呋虫胺的LC50值(95％ CI)分别为0.0025 (0.0021～0.0030)、0.0047 (0.0035～0.0062)、0.0190 (0.0156～0.0224)、0.1125(0.0921～0.1407)、0.0047(0.0035～0.0062)和0.1744(0.1653～0.1840) mg/L.结论 本实验室品系中华按蚊成蚊对拟除虫菊酯类杀虫剂敏感,对DDT有抗性.     

Evaluation of pyrethroids lambda-cyhalothrin, deltamethrin and permethrin against Aedes albopictus in the laboratory

Three pyrethroids were evaluated in the laboratory against Aedes albopictus females by exposure to insecticide impregnated papers, and to 4th instar Ae. albopictus larvae as insecticide solutions. Lambda-cyhalothrin was found to be the most effective pyrethroid when tested against Aedes albopictus adult females and larvae compared with that of deltamethrin and permethrin.     

拟除虫菊酯对中华按蚊繁殖率和生存力影响的观察报告

用拟除虫菊酯亚致死剂量处理中华按蚊,显示该蚊的生存力和繁殖率降低。以胺菊酯或溴氰菊酯处理中华按蚊,产卵的胚胎发育减慢。溴氰菊酯致死的部分中华按蚊幼虫体长缩短。     

溴氰菊酯和辛硫磷亚致死剂量对德国小蠊酶活性的影响

目的研究溴氰菊酯和辛硫磷亚致死剂量处理后德国小蠊羧酸酯酶、谷胱甘肽S-转移酶、乙酰胆碱酯酶的活性变化规律。方法采用分光光度计离体测定酶的活性,应用DPS软件进行统计分析。结果辛硫磷亚致死剂量处理德国小蠊后24h,羧酸酯酶活性降到最低,与处理前相比降低了79．33％,24h后其活性逐渐恢复,168h达到处理前的37．10％;溴氰菊酯亚致死剂量处理后,羧酸酯酶活性略有下降;经溴氰菊酯和辛硫磷亚致死剂量处理后,谷胱甘肽S-转移酶的活性略有下降,72h后其活性分别为处理前的74．97％和79．77％;经溴氰菊酯亚致死剂量处理后,乙酰胆碱酯酶活性24h略有升高,随后逐渐下降,经辛硫磷处理后其活性略有降低。结论经溴氰菊酯和辛硫磷亚致死剂量处理后德国小蠊体内酶活性在不同的时间与处理前存在差异。     

门帘浸泡溴氰菊酯防治侵入室内蚊虫的研究

白色棉纱编织的门帘,孔径6×3mm,椭园形,254孔/100cm~2,浸泡溴氰菊酯40mga.i./m~2,具有较满意的毒杀侵入室内蚊虫的作用。当年室内蚊虫死亡率高达90％以上,第二年还有85％以上的毒杀效果,但不经门帘外逃的蚊虫的死亡率却很低。此种门帘不能减少侵入室内蚊虫的数量,也不能明显地干扰蚊虫的吸血活动。     

Laboratory study to investigate the efficacy of cyfluthrin EW treated nets against phlebotomine sandflies

Toxic and feeding inhibition effect of cyfluthrin treated nets was assessed and compared with the activity of deltamethrin impregnated nets, before and after 2 and 4 washes against Phlebotomus papatasi. Impregnated cyfluthrin nets (50, 25, 12.5 mg active ingredient (a.i.)/m2) caused knock down and mortality rates higher than 90%, being of 100% at the highest dose, while the nets impregnated with deltamethrin (25, 12.5, 6.25 mg a.i./m2) showed low mortality rates (13.3-43.5%). Also after washing cyfluthrin at the dose of 50 mg a.i./m2 provided higher activity than deltamethrin (25 mg a.i./m2), being mortality rates within 24 hs of 66.7 and 48.9% for cyfluthrin and 38.0 and 2.1% for deltamethrin, respectively after 2 and 4 washes. Before washing, cyfluthrin (50 mg a.i./m2) significantly prevented blood feeding, with respect to both untreated (88.6%) and deltamethrin impregnated nets (56.8%). Deltamethrin (25 mg a.i./m2) showed low feeding inhibition (48.4%), although it was significantly higher than control. The washing of cyfluthrin impregnated nets (50 mg a.i./m2) produced a decrease of the feeding inhibition, being the reduction of 26.6% and 41.3%, respectively after 2 and 4 washes. Two washes of deltamethrin impregnated nets (25 mg a.i./m2) yielded a very high reduction of antifeeding inhibition (68.8%). These laboratory results if confirmed by field evaluation indicate cyfluthrin as good candidate for treatment of mosquito nets to be used against phlebotomine sandflies.     

Insecticide impregnation can restore the efficiency of torn bed nets and reduce man-vector contact in malaria endemic areas.

Three trials with torn bed nets impregnated with permethrin and deltamethrin were made under field conditions at the Soumousso Field Station and the Vallée du Kou rice-field area, both in Burkina Faso, and the Djoumouna fish pond area in the Congo Republic. Even a considerably torn correctly impregnated bed net could be an useful method for limiting human-anopheline contacts. But bed nets in poor condition, i.e. too little impregnated and too much torn, cannot protect the users against anopheline bites. Protection increases with insecticide concentration, but at a high dosage insecticide could have more a repellent than a killing effect. Therefore a balance has to be found for the optimum rate of insecticide treatment of bed nets to obtain a real reduction in malaria transmission and morbidity, in every epidemiological situation.     

Resistance to two pyrethroids in Anopheles sinensis from Zhejiang, China.

Probabilities of pyrethroid resistant genotypes in natural populations of Anopheles sinensis Wiedemann were measured with deltamethrin and permethrin. The median lethal concentrations (LC50s) of deltamethrin and permethrin in the susceptible larval population were 0.0209 and 0.1747 ppm, respectively. Under dosages that produced 99% mortality in susceptible laboratory strains of larvae, the lethal percentage of Cangnan larval field populations after 20 min of exposure was only 61.23% for deltamethrin and 64.92% for permethrin. This was much lower than those of other natural populations. Also, the probability of pyrethroid-resistant genotypes in Cangnan adult field populations was at the highest, reaching 0.5867. The results are discussed in relation to future mosquito control programs.     

宁夏部分地区淡色库蚊和家蝇的抗药性调查

目的 了解宁夏回族自治区银川市淡色库蚊和吴忠市、中卫市以及固原市家蝇对常用卫生杀虫剂的抗药性状况.方法 采用浸渍法测定淡色库蚊幼虫现场种群的半数致死浓度(LC50),采用微量点滴法测定家蝇成虫对杀虫剂的半数致死浓度(LD50).结果 双硫磷和吡丙醚对银川市淡色库蚊幼虫LC50值分别为0.001 2和0.563 2 mg...     

Second Pregnancies Among Immunologically Infertile Women: A Preliminary Report

Two females with sperm antibody activity in their blood serum and cervical mucus were treated with high dosages of methylprednisolone. Both patients bacame pregnant during therapy. Following the birth of their first offspring, one was treated with steroids and the other conceived without steroids in order to establish their second pregnancies. The sperm antibody activity showed a sharp decline in the blood serum and cervical mucus during therapy. The response of the females showed drastic modification in the antibody activity in that the females revealed a complete disappearance or a significant decrease in their initial sperm antibody reactions after treatment with high dosages of steroids.