农药助剂牛脂胺聚氧乙烯醚的毒性及其分析技术研究进展

牛脂胺聚氧乙烯醚是一类广泛用于草甘膦制剂的农药助剂。大量研究表明,该助剂的毒性大于其活性成分草甘膦,因而引起了国内外研究人员的关注。本文对牛脂胺聚氧乙烯醚的结构、毒性以及其目前在环境中的分布水平和分析方法等内容进行了综述,旨在为牛脂胺聚氧乙烯醚在我国农药助剂领域的进一步研究、规范使用和管控提供科学依据。     

那西肽预混剂组分HPLC检测方法的建立

为了建立那西肽预混剂组分测定的高效液相检查法,采用十八烷基键合硅胶为填充剂,以0.025%磷酸水溶液-乙腈(50:50)为流动相,检测波长为241 nm,并以该色谱条件对来自7个厂家的14批不同规格的那西肽预混剂进行了测定。综合结果给出组分的建议限度为:那西肽组分A的峰面积不得少于那西肽组分A与组分B峰面积之和的88.0%。该方法具有专属性强、耐用性好、操作简便等优点。     

家蝇幼虫双翅肽MdDpt I成熟肽基因的克隆与原核表达

对鸡沙门氏菌诱导家蝇幼虫构建的抑制性消减文库(SSH)中筛选得到的家蝇双翅肽I(Musca domesticaDiptericin I,MdDptI)基因进行克隆、表达,并对表达产物的抑菌活性进行初步研究。以沙门氏菌诱导家蝇幼虫cDNA为模板,采用cDNA末端快速扩增技术(RACE),对MdDptI基因进行扩增,并对扩增产物进行测序和生物信息学分析,进一步去掉信号肽并构建重组表达质粒pET-28a-MdDptI,转化大肠杆菌BL21(DE3),IPTG诱导表达,对表达产物进行SDS-PAGE电泳分析。借助亲和纯化获得目的蛋白,并验证目的蛋白的生物活性。MdDptI基因全长为419 bp,包含一个300 bp的完整开放阅读框(ORF),编码99个氨基酸,其cDNA序列与GenBank中登录号为FJ794602.1的家蝇双翅肽基因同源性为95%。构建了家蝇MdDptI基因的成熟肽原核表达质粒pET-28a-MdDpt-I,并获得成功表达,表达产物约为12 ku,与预期结果一致。纯化后的目的蛋白表现出一定的抑菌活性。本试验获得了MdDptI基因的全长序列,构建了原核表达载体,并成功获得表达纯化。     

土鳖虫冻干粉对高脂血症家兔模型的降脂作用

<正>传统中药土鳖虫性寒味咸,具有逐瘀破积、通络理伤之功效,为鳖蠊科昆虫地鳖(Eupolyphagasinensis Walker)或冀地鳖[Steleophagaplancyi(Boleny)]的雌虫干燥体[1]。土鳖虫的主要成分为氨基酸[2]、生物碱、挥发油和多种脂类成分[3]。临床上,土鳖虫在高脂血症、血栓性疾病和心脑血管缺血性疾病的治疗等方面被广泛应用[4]。随着其在医药方面的广泛应     

林蛙皮生物活性肽3种提取方法的比较研究

为了高效提取林蛙皮生物活性肽,试验采用甲醇提取法、超声波提取法、超声波辅助Alcalase蛋白酶酶解法进行比较研究。结果表明:超声波辅助Alcalase蛋白酶酶解法的提取效果最好,提取条件为加入Alcalase蛋白酶1.5 g,酶解温度为40℃,酶解时间为4 h。     

增强忧患意识加强兽用抗菌药物监管

随着我国经济社会的飞速发展,人们生活水平得到显著提高,动物产品的消费已从单一的量的需求转变为品质和安全的需求。为确保人民群众"舌尖上的安全",各级政府高度重视动物产品质量安全问题,不断拓展监管和服务职能,除了用最严格的监管打击违法行为外,还全面倡导开展动物产品质量安全风险源普查和风险评估工作,提前找到安全风险,提早防范,实现动物产品质量安全的源头控制。近几年,各级政府、各相关部门对瘦肉精、三聚     

黄脂肉、黄疸肉的鉴别与处理

黄脂肉和黄疸肉是在屠宰检疫过程中时常遇到的现象,如何正确的区分与鉴别是没有检疫工作人员需要掌握的基本知识,本文将对黄脂肉黄疸肉的感官鉴别、实验室鉴别以及卫生处理做一下介绍,意在供同仁交流与学习。     

猪致病性大肠埃希氏菌的药物敏感性试验

本实验采用世界卫生组织推荐的(K—B法)纸片琼脂扩散法,对从本地区猪场分离出的10株猪致病性大肠埃希氏菌,用10种临床上常用的抗菌药物对其进行了敏感性测定。结果:耐药现象严重,多重耐药性普遍存在。对猪致病性大肠埃希氏菌作用较强的依次是阿莫西林/克拉维酸(AMX/CA)、头孢唑啉(CZ)、氯霉素(C)、庆大霉素(GM),抑菌作用较差的是四环素(TC)、环丙沙星(CIP)、氨苄西林(AM)、氧氟沙星(DFL),链霉素(S)、磺胺(SMX)为中度敏感。     

Effect of Nutrient Restriction and Compensation on Weight,Serum Indexes and Gene Expression of Chest Fat Adipokines in Mongolian Lamb

To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages.     

云南景谷地区松脂研究的现状与对策

云南省景谷地区具有丰富的思茅松资源，盛产松脂，为此开展了高产脂种源培育等试验研究，对松树进行多种采脂方法的研究，调查各种采脂方法的实用性，并不断开发新的采脂方法。