玉米赤霉烯酮对动物繁殖性能的毒性作用及其机制

玉米赤霉烯酮（ZEA）一种由镰刀菌属产生的次级代谢物，化学结构与内源性雌激素相似，因此，ZEA可通过与雌激素竞争性结合雌激素受体，导致动物机体生殖激素代谢紊乱，诱发生殖器官形变及功能障碍，严重危害动物繁殖系统，解决ZEA污染问题己经成为当务之急。本文对ZEA的理化特性、毒性作用等进行综述，以期为有效缓解ZEA毒性及提高动物繁殖性能、促进畜牧业健康发展提供理论依据。     

5种杀虫剂对青菜黄曲条跳甲的毒力测定及田间药效

为了筛选有效防治青菜黄曲条跳甲的药剂,在室内测定了5种杀虫剂对黄曲条跳甲成虫的毒力,并开展了这5种药剂对黄曲条跳甲的田间药效试验。毒力测定结果表明,10%啶虫脒WP对黄曲条跳甲的毒力最高,28%杀虫·啶虫脒WP毒力最低,LC50分别为7.20 mg/L和18.63 mg/L,5种药剂的毒力大小依次为:10%啶虫脒WP>42%啶虫·哒螨灵WP>5%鱼藤酮SL>15%哒螨灵EC>28%杀虫·啶虫脒WP。田间药效试验结果表明,42%啶虫·哒螨灵WP和15%哒螨灵EC的防效最优,10%啶虫脒WP、28%杀虫·啶虫脒WP和5%鱼藤酮SL 3种药剂总体防效相当,但低于42%啶虫·哒螨灵WP和15%哒螨灵EC。综合来看,建议使用42%啶虫·哒螨灵WP 126~189 g/hm2、15%哒螨灵EC 90~135 g/hm2、28%杀虫·啶虫脒WP 294~420 g/hm2、10%啶虫脒WP 60~90 g/hm2、5%鱼藤酮SL 150~225 g/hm2对青菜黄曲条跳甲进行防治。     

Study on Liver-protective Effect of Chinese Herbal Compound Probiotics on Acute Liver Injury Layers

This experiment was conducted to investigate the liver-protective effect of Chinese herbal compound probiotics (CHCP) on acute liver injury layers.One hundred and eight 1 day old hens were divided into 4 groups with 3 replicates in each group and 9 layers per replicate in trial 1.The layers in model groups Ⅰ to Ⅲ were gavaged with 10% (V/V) soybean oil solution of carbon tetrachloride (SCCl₄) according to 1,2 and 4 mL/(kg·BW) at 14,28 and 35 d,respectively.The layers in control group were gavaged with 2 mL/(kg·BW) soybean oil.In trial 2,sixty 1 d layers were divided into 5 groups:Control group (soybean oil),model control group(SCCl₄)and low-dose,middle-dose and high-dose CHCP group (SCCl₄+1‰ CHCP,SCCl₄+2‰ CHCP and SCCl₄+4‰ CHCP respectively).CHCP were used by drinking water since 7 days.SCCl₄ were gavaged according to 2 mL/(kg·BW) at 14 and 28 d.The results showed as follows:The model of layers liver damage could be built by intragastric administration of 2 mL/(kg·BW) 10%(V/V) SCCl₄ at 14,28 d respectively,with the signs of hepatic steatosis,severe vacuolar degeneration,nuclear condensation and necrosis.Compared to the model control group,the serum AST levels in low,medium and high dose CHCP groups were decreased by 4.35% (P > 0.05),7.57% (P > 0.05) and 9.79% (P < 0.05),the serum ALT levels in medium and high dose CHCP groups were decreased by 34.92% (P < 0.01),36.51% (P < 0.01),the serum total bilirubin content in medium and high dose CHCP groups were decreased by 25.49% (P < 0.01),27.45% (P < 0.01).The liver cell congestion was reduced to varying degrees in different dose CHCP groups,and the liver cell had no vacuoles,arranged in neat rows,abundant cytoplasm and uniform in different dose CHCP groups.In conclusion,2‰,4‰ CHCP could reduce hepatocyte necrosis,decrease the serum activities of ALT,AST and total bilirubin levels,and had protective effect on hepatic injury induced by SCCl₄.     

Toxicity of cadmium and its competition with mineral nutrients for uptake by plants:A review

Cadmium(Cd)is a toxic heavy metal occurring in the environment naturally and is also generated through various anthropogenic sources and acts as a pollutant.Human health is affected by Cd pollution in farmland soils because food is the main source of Cd intake in the non-smoking population.For crops,Cd toxicity may result from a disturbance in uptake and translocation of mineral nutrients and disturbance in plant metabolism,inhibiting plant growth and development.However,plants have Cd tolerance mechanisms,including restricted Cd uptake,decreased Cd root-to-shoot translocation,enhanced antioxidant enzyme activities,and increased production of phytochelatins.Furthermore,optimal supply of mineral nutrients is one of the strategies to alleviate the damaging effects of Cd on plants and to avoid its entry into the food chain.The emerging molecular knowledge contributes to understanding Cd uptake,translocation,and remobilization in plants.In this review,Cd toxicity and tolerance mechanisms,agricultural practices to minimize Cd accumulation,Cd competition with essential elements(calcium,copper,iron,zinc,and manganese),and genes associated with Cd uptake are discussed in detail,especially regarding how these mineral nutrients and genes play a role in decreasing Cd uptake and accumulation in crop plants.     

重金属Pb与抗生素对发光菌的联合毒性研究

重金属是水环境中的典型无机污染物,随着水体中抗生素检出率的增加,重金属和抗生素的复合污染及其效应已成为环境领域的研究热点。通过研究重金属和抗生素对发光菌的发光抑制作用,可以了解重金属和抗生素的毒性效应,为评估重金属和抗生素复合污染在水环境中的潜在风险提供理论依据。本文利用便携式急性毒性检测仪,系统研究了重金属Pb和6种抗生素(四环素、氧四环素、氯四环素、磺胺二甲基嘧啶、磺胺甲基嘧啶和磺胺嘧啶)对费氏弧菌的单一和联合急性毒性,得到了单一污染物的半数效应浓度,并对重金属Pb和抗生素所组成的二元、三元复合污染体系的联合作用进行初步探讨。研究表明,当Pb与抗生素共存时,对发光菌的急性毒性急剧上升。因此,在评价Pb与抗生素二元或多元复合污染体系的生态风险时,应考虑其联合毒性作用。     

纳米氧化锌和纳米二氧化钛对尾草履虫急性毒性效应的比较研究

[目的][方法] 本研究以原生动物尾草履虫（Paramecium caudatum）为实验对象, 对目前广泛应用的两种纳米材料，纳米二氧化钛（TiO2）和纳米氧化锌（ZnO）的24小时急性毒性进行了比较研究，分析了草履虫在两种纳米材料胁迫下抗氧化酶活性的改变，并结合两种纳米材料的超微形态，探讨了纳米材料毒性效应的机制，为两种纳米材料的环境毒性监测与评价提供依据。[结果]结果显示：对尾草履虫的24小时半数效应浓度(24h-EC50)分别为51.580mg·L-1（TiO2）、0.444mg·L-1（ZnO）；最低有影响浓度(24h-LOEC)分别为1.712mg·L-1（TiO2）、0.352mg·L-1（ZnO）；以EC50浓度24小时胁迫尾草履虫，获得抗氧化酶活性改变为：超氧化物歧化酶(SOD)，过氧化氢酶(CAT)和过氧化物酶(POD)活性与对照组相比有不同程度的改变，经成对检验分析，两种纳米材料对尾草履虫的POD酶表现出较为明显的抑制作用。[结论]上述结果表明：纳米氧化锌对草履虫的24小时急性毒性大于纳米二氧化钛，这与纳米氧化锌对草履虫抗氧化酶的抑制作用更强，以及纳米氧化锌(30nm)的超微形态相较于纳米二氧化钛(25nm)更加纤细和尖锐有关；本研究获得的24小时急性毒性指标可用于监测和评价两种纳米材料的环境毒性，并为纳米材料的环境容量和生态安全阈值确定提供参考。     

血浆D-二聚体和超敏C反应蛋白检测在急性脑梗死中的临床价值

目的探讨血浆D-二聚体(D-dimer,D-D)及超敏C反应蛋白(high-sensitivity C-reactive protein,hs-CRP)水平与急性脑梗死(acute cerebral infarct,ACI)的关系。方法采用免疫透射比浊法检测102例ACI患者和50例正常对照者血浆D-D和hs-CRP水平。根据梗死灶大小102例ACI患者分为大梗死灶组、中梗死灶组和小梗死灶组,并进行相关统计分析。结果 ACI组患者血浆D-D和hs-CRP水平显著高于正常对照组(P0.01);大梗死灶组D-D和hs-CRP水平明显高于中、小梗死灶,而中梗死灶组D-D和hs-CRP水平高于小梗死灶组。结论监测血浆D-D和hs-CRP能为ACI的临床诊断、病情判断提供重要的参考依据。     

结石通片对小鼠的急性毒性试验及其对乙二酰胺致大鼠肾结石的作用研究

[目的] 研究结石通片对小鼠的急性毒性作用,对健康大鼠的利尿作用,以及对乙二酰胺致大鼠肾结石的调节作用。[方法] 取ICR小鼠40只,雌、雄各半,随机分为对照组与给药组,每组20只,观察结石通片给药前后小鼠的体重变化和死亡情况;另取SD大鼠36只,雌、雄各半,分为对照组、低剂量组（给予5%结石通片溶液）和高剂量组（给予10%结石通片溶液）,统计各组大鼠24 h排尿量;并采用42只雄性SD大鼠,考查结石通片对给予乙二酰胺（2%掺喂）后大鼠体重、肾重和肾重比的影响。[结果] 给予结石通片溶液后,连续观察7 d,小鼠的各项生理活动未见明显异常,给药组与对照组相比体重差异不显著（P>0.05）;与对照组比较,给予结石通片溶液后大鼠24 h内排尿量明显增加（P<0.01）;与对照组比较,给药组随着给药剂量的增加,结晶和结石的数量极显著（P<0.01或P<0.001）减少,形成结石的动物数量极显著（P<0.01或P<0.001）减少。[结论] 结石通片对小鼠无明显急性毒性作用,对大鼠利尿作用明显,并对乙二酰胺致大鼠肾结石具有明显抑制作用。     

不同形态硼对油菜幼苗铝毒的缓解效应及其FTIR特征分析

采用水培法,以油菜品种Cao 221167为试验材料,设置无机态硼酸(BA)和有机态山梨醇硼(SB)及不同Al~(3+)(0、100、200和500μmol L~(–1))处理,研究不同形态硼(B)对油菜幼苗铝(Al)毒的缓解作用及不同形态B之间的缓解效应差异,以及利用FTIR(傅里叶红外光谱)技术分析叶片各物质含量的变化。结果表明,Al毒胁迫下,不同形态B(BA和SB)处理,显著提高植株生物量和根系长度(0、100、200和500μmol L~(–1) Al毒胁迫下BA处理根长分别增加了52.15%、101.45%、366.70%和18.73%;SB处理分别增加了46.80%、133.98%、261.36%和10.77%),提高色素含量和SOD活性,而降低了Al含量、MDA含量和POD活性。不同形态B处理下,油菜幼苗在200μmol L~(–1) Al~(3+)处理下长势、生物量及色素含量最高。在500μmol L~(–1) Al~(3+)处理下,油菜幼苗株高、根长、总干鲜重及色素含量显著低于无Al处理;FTIR分析表明,Al毒胁迫下油菜叶片中蛋白质和低聚糖等含量明显上升,加硼明显降低了蛋白质和低聚糖的含量,且BA处理降低幅度明显高于SB处理。说明不同形态B(BA和SB)的添加均明显缓解Al毒,且BA对Al毒缓解效果优于SB,这为农业生产中施用何种硼肥来缓解Al毒起到一定的指导作用。