长江中下游地区湖北钉螺线粒体CO I基因遗传变异研究

从长江中、下游的江苏省丹徒区和邗江区、浙江省平湖市、湖北省武昌区、江西省余干县和彭泽县、安徽省安庆市和贵池区等5个血吸虫病流行省8个点现场采集湖北钉螺样本,提取基因组DNA、PCR特异性扩增线粒体DNA细胞色素c氧化酶亚单位1（COI）基因,用ClustalX 1．81软件进行多序列比对,MEGA4．0软件中的Kimu...     

乌桕抑螺生化机理的研究

为深入挖掘我国抑螺植物资源,加大血吸虫病植物防治力度,以我国重要经济树种、传统土农药——乌桕为研究对象,利用不同浓度的乌桕鲜叶石油醚提取液浸杀钉螺,对浸杀后钉螺的头、足部与肝脏,进行蛋白质、酶和糖元等生化因子的分析研究,为科学评价与合理利用抑螺植物提供方法及依据。     

枫香等3种植物水浸液灭螺效果的初步研究

对枫香、无患子、博落回等3种植物与枫杨、乌桕及其组合叶片水浸液抑螺效果在控温(25±1)℃和常温两种条件下进行了比较研究,同时初步研究了博落回不同部位水浸液的杀螺效果。结果表明:①在控温(25±1)℃和常温条件下,单一树种枫香、无患子、博落回叶片的水浸液均有较好的灭螺活性;②在相同的实验条件下,枫杨+乌桕+枫香等组合处理与单一植物材料水浸液的灭螺效果差异不显著,枫杨+乌桕组合对钉螺的抑制率略低于单一树种;(3)博落回不同部位灭螺效果有一定差异,根的灭螺效果明显低于叶和茎,不同部位的平均灭螺效果依次为:叶茎根。     

2009年洞庭湖区垸内钉螺空间特征分析

钉螺为血吸虫的唯一中间宿主,了解钉螺的空间分布规律对于控制血吸虫病有一定的作用。运用GIS空间统计和地统计方法,分析了2009年洞庭湖血吸虫病疫区活螺密度的空间分布规律:活螺密度呈高聚类模式分布,主要沿湖沿河分布,样点具有强烈的空间自相关性,其中反向聚集区域有(z<-2.58)567个点,正向聚集区域有(z>2.58)540个点,说明钉螺点的辐射效应比较高,血吸虫病容易扩散到周边地区。同时,建立了活螺密度的空间预测图,得出了样点数据的半变异函数呈多项式分布。     

环形生态水槽流动的特性研究

实测了环形生态水槽内的流速分布。采用柱坐标系下的κ-ε湍流模型及SIMPLE算法,对该流场进行了数值模拟。从计算结果和实验资料的分析比较看出,计算结果可靠。在此流场内进行了钉螺的运动特点的实验研究,结果表明钉螺具有流速敏感性,对研究钉螺的随流扩散具有重要意义。     

遥感与地理信息系统技术在洪湖市湿地钉螺分布研究中的应用

血吸虫(Schistosoma)是一种寄生虫,可以寄生在人体或动物体内,主要依靠钉螺(Oncomelania hupensis)繁殖.遥感技术作为一种监测手段,辅助地理信息系统空间分析,可以有效地对钉螺分布区进行监测和数据提取.运用阈值提取和空间分析的方法,对2001年洪湖市钉螺栖息地的分布情况进行了分析和研究.在归一化植被指数为0.2～0.3和穗帽湿度指数为7～13的阈值下,提取出可疑钉螺栖息地分布的数据,根据实际钉螺分布图对其进行精度评价,其正确率达到86.20%.82.77%的可疑钉螺栖息地分布在沟渠之中,这说明沟渠具有适合钉螺生长的最佳环境条件.遥感与地理信息系统技术相结合的研究方法对洪湖市钉螺分布监测具有可行性,可以作为血吸虫防治工作的新方法.     

A Comparative Study of Distribution of Heavy Metal Concentrations in the Pomacea insularum Collected from Polluted and Unpolluted Sites of the Freshwater Ecosystem in Malaysia

The snails (Pomacea insularum) were collected from polluted and unpolluted sites at Juru River and the Universiti Putra Malaysia Lake, respectively. Besides the shells, the soft tissues of snails were dissected into 6 different parts: intestine, operculum, foot, pennial sac, lung sac and the remainder. They were analyzed for the concentrations of Cu, Cd, Zn, Pb, Ni and Fe. The present study found 6 interesting points. First, all the metal levels found in the different parts of P. insularum collected from Juru River were significantly (p<0.05) higher than those in the snails of unpolluted lake. These results were also supported by the sediment data in which the Juru River sediment had significantly (p<0.05) higher levels of metal than those in the unpolluted lake. Second, the high levels of Cd and Pb were found in the shell of P. insularum, indicating that it is a potential biomonitoring material for these metals. Third, intestine accumulated elevated levels of Zn, Ni and Fe and thus is a potential biomonitoring organ for the 3 metals. Fourth, high levels of Cu were found in the lung sac and this phenomenon could be related to this metal binding to metallothionein in this organ. Fifth, elevated level of Pb found in the soft tissues of P. insularum indicated that this snail is not suitable for human consumption since its pollution level was higher than the food safety guideline for Pb. Sixth, there was no significant difference (p>0.05) between the different sizes (small sizes: 30.5-33.2 mm; large sizes: 37.7-40.4 mm) of P. insularum. The first 5 points supported the use of different soft tissues of P. insularum as biomonitoring organs of heavy metal pollution in the freshwater ecosystem in Malaysia although further validation is required.     

山丘型抑螺防病林的营建模式

<正>山丘地区地理和自然环境因素复杂,血吸虫治理难度大,治理时应根据钉螺分布的特点,采取分类分模式治理。据调查,山丘地区钉螺的分布和数量以荒坡、沟渠和河滩等处密度较大,为血吸虫病生态防治的重点地段;四旁(田边地坎、溪沟两旁、房前屋后、道路两旁)钉螺分布密度次之,但这些区域人畜活动更为频繁,应作治理的主体区域。依据血吸虫生物发育规律和     

斯氏并殖吸虫第一中间宿主拟钉螺属一新种记述 (中腹足目, 盖螺科)

为调查斯氏并殖吸虫拟钉螺宿主,现场采集螺标本,进行形态分类和生态考察及螺体寄生虫检查.发现拟钉螺属(Tricula)一新种,命名为建欧拟钉螺(Tricula jianouensis sp.nov.),螺壳高3.125 mm,壳宽1.600 mm,体螺层高1.125 mm,壳口长径1.275 mm,壳口宽径0.925 mm.螺口外缘翘起呈铲状;轴缘与外缘形成较窄夹角,内唇嵴明显高出,与体螺层间有一沟状隙.齿舌每一横列有7枚齿,齿式:2-1-2/2-2·3-1-3·11(14)·14(15).该螺充当斯氏并殖吸虫第一中间宿主,斯氏并殖吸虫尾蚴感染率为0.11%.     

滩地林业血防工程抑螺效应及其成因研究

在洞庭湖区滩地对不同类型杨树抑螺防病林采取定位观测的研究方法,对滩地钉螺种群变化与抑螺防病林营造措施、林龄的关系及其内在机制进行了研究。结果表明:林分郁闭前,通过林农复合等林地土壤管理措施,改造钉螺孳生环境,可有效降低活螺和感染螺密度;林分郁闭后,林地水分、光照、植被等环境因子朝着不利于钉螺孳生的方向演变;滩地抑螺防病林生态系统抑螺效果具有显著性和持续性。