杀虫威对棉铃虫、烟青虫、菜青虫的防治效果

田间试验表明 ,新氨基甲酸酯杀虫剂杀虫威对鳞翅目害虫棉铃虫、菜青虫、烟青虫防治效果优良。杀虫威 2 0 %EC在河南防治 2代棉铃虫使用剂量 1 0g (a.i.) 667m2 药后 2～ 7d ,校正防效为90 65 %～ 97 72 % ,在山东药后 3～ 5d ,防效为 85 1 7%～ 91 2 3 % ,7 5g (a .i.) 667m2 相应药效两地分别为 88 41 %～ 95 2 7%和 81 40 %～ 85 61 % ;防治 3代棉铃虫使用剂量 2 0g (a.i.) 667m2 药后 2～ 5d ,防效两地分别为 83 93 %～ 86 1 5 %和 85 5 3 %～ 88 2 9% ,1 5g (a .i.) 667m2 相应药效分别为 77 66%～80 2 3 %和 78 5 0 %～ 83 75 %。防治烟青虫使用剂量 1 0g (a.i.) 667m2 药后 3～ 7d校正防效为 85 5 7%～ 88 2 9% ,7 5g (a .i.) 667m2 相应药效为 81 5 1 %～ 86 1 1 %。防治菜青虫使用剂量 7 5～ 1 0g (a .i.) 667m2 药后 3～ 7d防效为 87 5 0 %～ 96 1 1 %。     

N-ethyl-N-nitrosourea mutagenesis produced a small number of mice with altered plasma electrolyte levels

Background  

Clinical chemical blood analysis including plasma electrolytes is routinely carried out for the diagnosis of various organ diseases. Phenotype-driven N-ethyl-N-nitrosourea (ENU) mouse mutagenesis projects used plasma electrolytes as parameters for the generation of novel animal models for human diseases.     

水分胁迫对巴西香蕉幼苗水分状况、质膜透性和根系活力的影响

最适宜的土壤水分含量是田间持水量的71%～80%.     

高山被孢霉亚甲基四氢叶酸脱氢酶的克隆、表达和功能鉴定

叶酸代谢途径中的亚甲基四氢叶酸脱氢酶（MTHFD）可将5,10-亚甲基四氢叶酸氧化为5,10-甲炔基四氢叶酸,此过程会生成NADH或NADPH。对高山被孢霉中的MTHFD基因进行克隆、表达和功能鉴定,可进一步阐明脂质合成所需还原力NADPH的来源。首先对MTHFD序列进行分析,并以pET28a（+）质粒为载体构建了MTHFD的表达载体,然后转化至大肠杆菌BL21中进行诱导表达。进一步利用Ni金属螯合层析纯化目的蛋白,采用比色法分析酶反应产物,表明纯化蛋白质具有MTHFD活性。高山被孢霉MTHFD对NAD⁺和NADP⁺均具有催化能力,但更偏好于将NADP⁺转化为NADPH。最后对高山被孢霉进行发酵培养,发现MTHFD的转录水平在脂质开始积累后发生了明显的上调,表明MTHFD在高山被孢霉脂质合成过程中发挥重要作用,很可能是脂质合成所需NADPH的关键来源。这为对高山被孢霉进行分子改造,使之成为高产各种多不饱和脂肪酸的细胞工程提供了理论依据。     

Diversity and Vertical Distribution Characteristics of Vascular Epiphytes in Bulong Nature Reserve Mengsong Section,Xishuangbanna

The first survey of vascular epiphytes was conducted using ground based inventory assisted by single rope technique in the recently established Bulong Nature Reserve, Xishuangbanna, China. Results indicated that vascular epiphytes were abundant and diverse there. On a total of 77 phorophytes in six plots (96 trees were examined in total, covered ca. 02ha area), 1756 individuals were recorded and were identified to 103 species (47 genera, 14 families). Compared with other regions, the epiphytes were as diverse as Paleotropics, and more diverse than temperate zone, but significantly less than the Neotropics. Orchids and ferns comprised 60%, 24% of the total flora, respectively, while others only took up 16%. The highest species richness and richest life form diversity was found in the middle canopy zone from 10 to 15m (51% of total species), where also supported high individual abundance (19% of total individuals). Besides the middle canopy, the most abundant zone of epiphyte individuals was detected at the base of the trunk (zone 0-5m, 24% of total individuals and 37% of total species), indicating another important niche for epiphytes in this forest environment. Primary hemiepiphytic figs were rare in the area and were not found on the surveyed host trees, while hemiepiphytic Araliaceae species (Schefflera elliptica and Tupidanthus calyptratus) were popular.     

中国云南洱海周边小兽体表恙螨多样性

本文运用Shannon_Wiener,系统聚类分析方法（SPSS 13.0软件）和Levins'niche等对云南大理洱海周边3 303头小兽体表寄生恙螨的物种多样性、群落结构、相似性、分布和生态位进行研究。调查点位于我国11大鼠疫自然疫源地之一,此地也是我国恙虫病和流行性出血热的流行地区。选择的洱海周边3个不同方位恰好处于东部无量山、南部哀老山和西部苍山,由于洱海的天然隔离使这3个方位形成了同地域（经度、纬度、海拔和动物地理区划相同）异生境的地理景观。从洱海的3个方位共计诱捕小兽3 303头,分类鉴定为4目,7科,15属,21种。从小兽体表共计检获56 895头恙螨,分类鉴定为3亚科,13属,109种。恙螨的丰富度、分布和物种多样性随着宿主和生境的不同而存在着显著的差异。恙螨只有幼虫寄生,强烈受到环境（温度、降雨量和生境）的影响。恙螨的宿主特异性很低,恙螨的群落相似性大小与宿主小兽之间的近缘性高低呈现较低的关联度。结果提示,大部分的宿主小兽和恙螨之间协同进化程度不高; 恙螨的这些特征从流行病学的角度来看,恙螨作为医学媒介生物在宿主之间传播疾病的潜能较大。     

Induction of arachidonate 12-lipoxygenase (Alox15) in intestine of iron-deficient rats correlates with the production of biologically active lipid mediators

To identify novel genes associated with iron metabolism, we performed gene chip studies in two models of iron deficiency: iron-deprived rats and rats deficient in the principal intestinal iron transporter, divalent metal transporter 1 (i.e., Belgrade rats). Affymetrix rat genome gene chips were utilized (RAE230) with cRNA samples derived from duodenum and jejunum of experimental and control animals. Computational analysis and statistical data reduction identified 29 candidate genes, which were induced in both models of iron deficiency. Gene ontology analysis showed enrichment for genes related to lipid homeostasis, and one gene related to this physiological process, a leukocyte type, arachidonate 12-lipoxygenase (Alox15), was selected for further examination. TaqMan real-time PCR studies demonstrated strong induction of Alox15 throughout the small and large intestine, and in the liver of iron-deficient rats. Polyclonal antibodies were developed and utilized to demonstrate that proteins levels are significantly increased in the intestinal epithelium of iron-deprived rats. HPLC analysis revealed altered intestinal lipid metabolism indicative of Alox15 activity, which resulted in the production of biologically active lipid molecules (12-HETE, 13-HODE, and 13-HOTE). The overall effect is a perturbation of intestinal lipid homeostasis, which results in the production of lipids essentially absent in the intestine of control rats. We have thus provided mechanistic insight into the alteration in lipid metabolism that occurs during iron deficiency, in that induction of Alox15 mRNA expression may be the primary event. The resulting lipid mediators may be related to documented alterations in villus structure and cell proliferation rates in iron deficiency, or to structural alterations in membrane lipid composition.     

丹江口水库三种鲤科鱼类寄生木村小棘吻虫的季节动态

作者于2004年2月至2005年2月调查了丹江口水库木村小棘吻虫Micracanthornhynchina motomurai(Harada,1935)感染三种小型经济鲤科鱼类--马口鱼(Opsariichthys uncirostris)、宽鳍(鱼鼠)(Zacco platypus)和油(粲鱼)(Hemiculter bleekeri bleekeri)的季节动态情况.在感染率和感染丰度方面,寄生于马口鱼和油(鱼鼠)的木村小棘吻虫呈现出显著的季节变化:秋冬季节感染率和感染丰度都比较高,而春夏季节比较低;与此不同的是,寄生于宽鳍(鱼鼠)中的木村小棘吻虫则全年都维持着较稳定的感染水平;木村小棘吻虫种群在三种宿主体内的总体感染丰度差异显著,但都呈聚集分布,三者的方均比与感染率和感染丰度之间无显著相关关系.     

中国云南洱海周边大足鼠的体表寄生螨

用U检验和相关分析的统计方法对2003～2004年云南洱海(中国滇西北著名的淡水湖泊)周边251只大足鼠体表寄生螨进行了调查.调查点是我国11大鼠疫自然疫源地之一,也是我国恙虫病和出血热的流行地区.大足鼠已经被鉴定为鼠疫、汉坦病毒、恙虫病和流行性出血热的储存宿主.我们的研究发现大足鼠携带好几种与人兽共患病有关的螨类.为了丰富大足鼠体表寄生螨的研究,在此,对大足鼠的体表寄生螨群落和体表寄生螨医学和兽医学的重要性进行了描述.有191只大足鼠寄生有体表寄生螨,侵染率为76%.采集到的体表寄生螨有35种,包括15种恙螨和20种革螨.其中6种以前已经被证明是人类疾病的主要媒介.因此大足鼠很显然成为流行性出血热和恙虫病等病原体的贮存宿主.     

密云水库的浮游植物群落结构与密度

 1998年的调查研究显示,密云水库库区水体的浮游植物群落为硅藻(Bacillariophyta)—绿藻(Chlorophyta)型,细胞密度为358.76×104·L-1。湖泊的营养特征为浮游植物响应型。1988～1998年库区水体总氮增长48.7％,总磷增长31.2％,浮游植物细胞密度增长41.7％,库区水体已为中营养,并出现了富营养型浮游植物指示种类,例如斜生栅藻(Scenedesmus obliquus(Turp)．Kütz．),铜绿微囊藻(Microcystis aeruginosa Kütz．),湖泊色球藻(Chroococcus limneticus Lemm．)。水体向富营养化发展趋势明显。应加强水环境保护,增加密云水库流域植被覆盖度,净化、涵养水源,以保证密云水库向北京市供水的质量和数量。