牛羊猪肉组织中伊维菌素残留量检测HPLC法的改进

对牛、羊、猪肉组织中伊维菌素残留的检测方法进行了改进，样品用乙腈提取，用正己烷脱脂并于50℃减压蒸干。残留物用乙酸乙酯溶解，过C18SPE柱，用乙酸乙酯-甲醇（1：1）溶液洗脱；收集流出液和洗脱液，合并蒸干后于（50±3）℃减压干燥20min；残留物用N-甲基咪唑溶解并与三氟乙酸酐-乙腈（1：2）溶液于（67±2）℃衍生1h。用配荧光检测器的高效液相色谱仪检测。本方法平均回收率为（102．0±6．6）％，批内RSD〈10％，伊维菌素浓度在5～400ng／mL时，呈线性关系，r=0．9997。检测限为2μg／kg。     

鸭生长激素(GH)基因编码区及调控区多态性分析

根据鸭生长激素基因编码区及调控区的序列设计8对引物,利用PCR-SSCP方法对北京鸭、西湖野鸭、樱桃谷鸭、金定鸭、山麻鸭、荆江鸭、绍兴鸭、缙云麻鸭等8个鸭种进行单核苷酸多态性分析。结果共发现3个突变位点,分别为230处（C→G）、244处（C→A）和3 701处（C→T）。前两处突变位于5′调控区,3 701处突变位于编码区第4外显子,但该编码区的突变是沉默突变,3′调控区表现了高度的保守性。统计结果发现：⑴在5′调控区基因座上,金定鸭的等位基因B频率显著高于其他品种;⑵在外显子4基因座上,基因型频率的分布与品种有关,且肉用型鸭的CC基因型频率显著高于蛋用型。可以推测,本研究所检测到的基因座可能与生产性能相关。     

部分引进猪种α1-岩藻糖转移酶基因多态性研究

本研究采用PCR RFLP技术对4个引进猪种杜洛克、约克夏、长白猪和皮特兰共计122头猪的FUT1基因进行了多态性分析。结果表明：4个猪种在该FUT1基因座位存在多态性，但抗性基因型AA仅在杜洛克和皮特兰猪中分布。卡方检验结果表明，长白猪与皮特兰间FUT1基因基因型分布差异极显著，长白猪与杜洛克猪之间差异显著，约克夏与皮特兰间差异也显著。     

合肥野生动物园5种雉鸡接种新城疫疫苗后抗体水平测定

选择成年白冠长尾雉5只,白腹锦鸡5只,白鹇3只,红腹锦鸡3只和孔雀11只,同时用L系弱毒冻干苗和新城疫油乳剂灭活疫苗进行免疫接种,通过血凝抑制试验(HI)测定其抗体滴度.结果表明,在免疫接种后26 d,白冠长尾雉抗体效价为9.8log2,白腹锦鸡为8.0log2,白鹇为8.0log2,红腹锦鸡为10.7log2;孔雀在免疫后接种0、8、15、20、25 d,抗体水平分别为3.8log2、5.0log2、6.2log2、7.5log2及8.2log2.     

Effect of different PRA serum levels from patients with β-thalassemia on the proliferation and differentiation potential of the hematopoietic stem cells /progenitor cells of cord blood

AIM: To probe the effect of different panel reactive antibody(PRA) serum levels from patients with β-thalassemia on the proliferation and differentiation potential of the hematopoietic stem /progenitor cell of cord blood.METHODS: 1×105 mononuclear cells (MNCs) isolated from umbilical cord blood were incubated with different PRA serum levels (0 μL,50 μL,100 μL) respectively and complement,inoculated into the methylcellulose cultural system.The proliferation and differentiation potential of the hematopoietic stem /progenitor cell of cord blood by the colony formation assay were detected on day 7 and day 14,respectively.RESULTS: After culture of 7 days,the total colonies and CFU-GM were 88.20±9.41,79.00±11.39 in group A and 88.60±9.12,79.20±10.44 in group B,which were significantly higher than those of 20.60±7.39,15.20±4.66 in group C and those of 4.00±2.05,1.40±0.51 in group D (P<0.01).Meanwhile compared with group A and group E,no significant difference was found (P>0.05).After culture for 14 days,the total colonies and CFU-GM were 216.00±31.10,117.40±24.80 in group A and 213.20±31.06,116.00±19.75 in group B,which were significantly higher than those of 97.80±14.43,32.80±8.10 in group C and those of 31.40±13.41,8.40±4.30 in group D (P<0.01).The CFU-GEMMs were 45.60±8.51 in group A and 42.60±7.03 in group B,which were significantly higher than those of 20.80±6.96 in group C and those of 7.80±6.06 in group D (P<0.05).The BFU-MK was 12.80±4.42 in group A and 11.00±2.74 in group B respectively,which were significantly higher than that of 1.00±0.55 in group D (P<0.05).The CFU-E in group B 17.20±4.03 was significantly higher than that of 5.60±2.87 in group D (P<0.05).Meanwhile compared with group A and group E,no significant difference was found (P>0.05).By the Kendall test,there were negative correlations between the level of PRA serum and the total colonies,CFU-GM on day 7,the total colonies,CFU-GM,CFU-GEMM,BFU-E,BFU-MK on day 14 (tau-b=-0.793,-0.849,-0.808,-0.804,-0.645,-0.674,-0.624,P<0.01).There was a negative correlation between the level of PRA serum and CFU-MK on day 14 (tau-b=-0.466，P<0.05).CONCLUSION: PRA sera inhibit the colony in the colony cultures of the hematopoietic stem cells/progenitor cells in cord blood.The inhibition depends on the level of PRA sera.The higher the level of PRA sera,the stronger the inhibition is observed in our study.     

人口发展与城市化水平预测——以乌兰察布市为例

科学预测人口城市化水平,对相关政策的制定、制度的改革、城市配套设施的建设以及解决就业问题都具有重要意义。本文以乌兰察布市为例,对地区总人口进行预测的基础之上,运用劳动力结构模型、劳动力地域转移模型等多种数学模型,预测了城镇人口城市化水平和非农业人口的城市化水平。最后,选取与城市化相关的七项指标,对城市化水平进行了综合预测。     

总结经验提高对小麦赤霉病预防工作重要性的认识

小麦赤霉病是影响安徽省小麦高产、稳产、优质的重要障碍,尤其是在本省沿淮及其以南麦区,对该病的防治更应作为小麦高产、优质栽培的一项重要措施予以高度重视。为阐述小麦赤霉病防治的重要性,笔者近年在凤台县进行了有关调查和试验。     

鲜食大豆新品种辽鲜1号的高产栽培技术

辽鲜1号是辽宁省农科院作物所选育的鲜食大豆新品种.我区自2002年引进后表现高产、稳产,熟期适中,品质好、商品性佳;经试验,得出高产栽培技术措施为:露地在4月初播种,30万株/h㎡,条播;施225 kg/h㎡过磷酸钙作基肥,90 kg氯化钾、75 kg尿素作苗肥;水分管理宜前干后足;病虫害防重于治和治早、治小;适时采收,提高效益.     

绿色环保胶的产生及其应用

<正>1 E_1级绿色环保型人造板用脲醛树脂的产生众所周知,脲醛树脂是木材工业最常用的胶黏剂。它的最大的特点是价格低廉,其物理力学性能完全可以满足木材工业所要求的胶合性能,但是脲醛树脂也有其先天不足的缺陷,当热压时释放出大量的刺激性气体——游离甲醛,严重危害工人     

案例教学在初中生物教学中的实践

生物学是一门自然科学,是以科学实验为基础的。案例教学是是一种新型的教学形式。在中学生物教学活动中开展案例教学,容易激发学生学习动机。文章就初中生物教学中的案例教学设计进行探讨。