4种实蝇线粒体DNA全序列测定

橘小实蝇(Bactrocera dorsalis)、木瓜实蝇(Bactrocera papayae)、杨桃实蝇(Bactrocera carambolae)和菲律宾实蝇(Bactrocera philippinensis)的成虫和幼虫的形态特征十分相近,难以区分.本文对4种实蝇的线粒体DNA全序列进行测定,序列在GenBank上登录(登录号分别为:DQ917577,DQ917578,EF014414,DQ995281),并对4个种的线粒体DNA全序列进行序列分析,为建立基于线粒体DNA序列分析的快速鉴定方法提供基础.     

基于耗散结构的草原生态经济系统的动态分析

以耗散结构理论为基础,草原生态经济系统为研究对象,用熵作为度量标准,从草原生态系统的冲击力、复合承载力和反馈力三个角度分析了草原生态经济系统可持续发展面临的危机与挑战,并提出了通过构建完善的草原生态补偿机制增加草原生态经济系统的负熵流,通过转变牧区经济的发展方式,完善保护草原生态经济系统的政策减少正嫡的流入,从而实现草...     

Methyl donors dietary supplementation to gestating sows diet improves the growth rate of offspring and is associating with changes in expression and DNA methylation of insulin‐like growth factor‐1 gene

The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB₁₂, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (p < 0.05), and greater hepatic IGF‐1 protein (p = 0.03) and muscular IGF‐1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor.     

高致病性猪蓝耳病病毒GS/LZh/07株的分离、鉴定及其非结构蛋白Nsp2基因特性分析

将高致病性猪蓝耳病疑似病料接种Marc145细胞,发现该病料可使Marc145细胞产生CPE,应用猪蓝耳病病原检测试剂盒从细胞培养物中检测到PRRSV,命名为Gs/Lzh/07株。同时应用RT-PCR方法扩增该分离毒株的非结构蛋白Nsp2基因,并进行了序列测定,发现所扩增到的Nsp2基因有90个核苷酸的缺失。序列比对结果表明：该分离病毒Nsp2基因与经典毒株PRRSV-ch-1a核苷酸同源性为83.0%,氨基酸同源性为72.7%;与高致病性变异毒株NX和SD核苷酸同源性为95.5%,氨基酸同源性为90.9%,可见该毒来源于2006-2007年流行毒株,说明高致病性猪蓝耳病变异病毒已经在甘肃省存在。该毒株的成功分离为高致病性猪蓝耳病流行病学调查分析提供数据,也为预防控制该病积累了资料。Nsp2的特性分析为揭示高致病性猪蓝耳病PRRSV在甘肃省的流行特点提供参考。     

芦笋全雄新品种'WF-8'

芦笋‘WF28’是利用芦笋雄性系两性株选育出的全雄一代杂种, 生育期为245 d, 平均茎高220 cm左右。白笋色泽洁白, 笋条直, 粗细均匀, 质地细嫩, 包头紧密, 无空心, 单支笋质量51 g左右,一级笋率92.2%。平均产量为15 000 kg·hm^-2。白笋铁含量为0.043 mg·g^-1。适宜白笋、绿笋栽培。     

青枯病原细菌无毒菌株诱导番茄防御酶系及粗提液抑菌活性的影响

 用紫外诱变法获得的青枯无毒菌株诱导番茄,研究了诱导番茄细胞内防御酶系及组织粗提液抑菌活性的影响。结果表明:番茄经无毒菌株处理后,体内与抗病反应相关的苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)及超氧化物歧化酶(SOD)等防御酶系活性均显著增加。无毒菌株可诱导产生植株体外和体内对致病菌有抑制作用的抑菌物质。表明青枯无毒菌株产生诱导抗性的机制可能是激活了植物本身的抗病代谢过程。     

Perinatal hypoxia induces subsequent retinal degeneration in the offspring of ovoviviparous fish, Xiphophorous maculates

OBJECTIVE: This experiment evaluated the perinatal hypoxic effect on the retina of offspring of the ovoviviparous fish. ANIMAL STUDIED: The ovoviviparous fish Xiphophorous maculates was used for the experiment. PROCEDURE: The mothers were kept in a hypoxic environment of 3.5% oxygen for 6 h, starting 30 h before hatching. Subsequently, the retinae of the offspring were fixed, sectioned at 6 microm and evaluated microscopically from the age of 1 to 35 days. RESULTS: Degeneration of the outer nuclear layer of the retina was noted on the 3rd day and severe retinal degeneration was observed on the 35th day. Immunocytochemistry confirmed apoptosis by TUNEL reaction. There was no difference in neovascularization, as revealed by vascular endothelial growth factor, between controls (group 1) and hypoxic fish (group 2). CONCLUSIONS: Perinatal hypoxia could have long-lasting effects on the central nervous system in some species.     

银杏实生树不同发育阶段个体内源激素含量的变化

以不同年龄银杏实生树为试材,研究芽尖和叶片中内源激素赤霉素(GA3)、玉米素(ZT)、吲哚乙酸(IAA)和脱落酸(ABA)含量与个体发育阶段的关系。结果表明,7龄期和13龄期银杏实生树芽尖和叶片中上述4种内源激素含量无明显差别,同时与13龄期首次开花的雄株接近,但却和3龄期有显著差异。可见实生树在7龄期前后树高2.5～3.0m已处转变期;随后树体继续生长增高到12～13m,在13龄期前后首次出现雄花和雌花开始进入成年期。芽尖中上述4种内源激素水平不是转变期进入成年期的惟一控制因子。转变期长可能是实生树迟果的原因之一。     

香芋复合饮料的研制

为了确定香芋复合饮料的最佳配方,以香芋、干花和大米等为原料,通过打浆、加热研磨等
工艺,加上后期调配获得最终产品。通过正交试验以及对饮料的综合感官评价和理化分析,得到了最佳的
配方。结果如下：当香芋添加量为100 g,水的添加量为1 100 mL 时,蜂蜜和柠檬汁的添加量分别为9%
和0.07%;粳米（晚粳宁88）添加量为10 g;干茉莉花的添加量为2 g;牛奶和枸杞的添加量分别为5 mL
和1 g。该产品具有茉莉花和牛奶的清香和乳香,口感细腻,为淡乳黄色液体,具有营养保健功效。     

用免疫抑制小鼠快速培育抗苏拉明伊氏锥虫

将伊氏锥虫克隆ＪＧｍｃ５用环磷酰胺处理的免疫抑制小鼠频繁地连续传代，并予以亚治疗剂量的苏拉明治疗，连续传代１４次，历时８８日，即获得对苏拉明具有高水平抗药性的伊氏锥虫群体。在用免疫活性正常的健康小鼠测定抗药性时，此抗苏拉明锥虫群体仍保持高水平的抗药性，ＣＤ１００＞４００ｍｇ／ｋｇ。在以体外药敏试验测定时，其ＩＣ５０为１２３．２μｇ／ｍｌ。实验结果表明，宿主免疫系统的损害，在实验条件下，可导致伊氏锥虫迅速产生抗药性。在野外条件下，机体免疫系统的损害对锥虫抗药性的产生可能也起一定作用。