乐果液相色谱与气相色谱检测方法的比较

摘 要：【研究目的】通过应用液相色谱法（HPLC）和气相色谱法（GC）对乐果测定的参数进行比较,为乐果检测方法的选择提供参考。【方法】分别应用气相色谱和高效液相色谱法对乐果检测条件进行优化,对这两种测定方法的灵敏度、线性相关性、稳定性及添加回收率的等参数测定结果进行比较。【结果】用液相色谱法测定乐果最低检测限为0.01mg/L,比用气相色谱法（最低检测到0.1mg/L）测定时有更高的灵敏度;HPLC检测（r＝0.9990）较GC（r＝0.9937）有更好的线形相关性;在乐果浓度低于0.1mg/L时,用液相色谱法对乐果进行测定有很好的稳定性,在浓度高于0.1mg/L,两种测定方法的稳定性相当。【结论】用液相色谱法测定乐果完全可以达到农药登记残留试验准则的要求,它比气相色谱法更适合乐果的微量及常量的检测。     

RNA干扰技术在小麦中的应用研究进展

小麦是六倍体,其染色体组中存在着大量的同源基因,其育种的主要目标是获得可遗传的优良性状.RNA干扰(RNAi)是指由双链RNA介导的转录后基因沉默.该技术具有两大特点:一是可同时沉默多基因家族及多倍体中的同源基因;二是其沉默效应可在后代中稳定遗传.这使得RNAi在小麦功能基因组学和品质改良研究中的应用具有独特优势.本文对RNAi在小麦功能基因组学和品质改良研究中的应用及研究进展进行了总结,指出了目前存在的问题,并阐明了RNAi在小麦研究中的应用前景.     

矮化富士苹果树冠不同部位果实品质分析

以矮化富士苹果树为试材,采集不同树冠方位果实,对品质进行测定及分析。研究了苹果矮化栽培模式对不同树冠方位果实品质的影响。以期明确矮化苹果不同树冠方位果实品质性状差异,为进一步改造老果园及优化树体结构提供参考依据。结果表明:外在及内在品质中上部优于下部,东南部优于西北部;大量及微量元素中下部优于上部,水平方向无明显规律。     

生物纤维饲料在蛋鸡生产中的应用研究

生物纤维饲料是对玉米淀粉湿磨国工过程中的浸泡液，黄浆和玉米皮渣等副产品经生物发酵方法而形成的一种新型饲料。本文研究了生物纤维饲料在蛋鸡饲养中的饲喂效果。试验表明，半风干生物纤维饲料（含水分26．68％）以5％比例添加蛋鸡日粮中的饲喂效果与对照组相比，日均产蛋量提高6．4％，平均产蛋率提高6．05％，料蛋比下降13．01％，毛利润提高90．70％，而风干生物纤维饲料（含水分15．44％），则以10％比添加于蛋鸡日粮时，表现出较明显的增产效果，其与对照组相比，日均产蛋量提高4．04％，平均产蛋率提高4．18％，料蛋比下降4．09％，毛利润提高25．74％。     

人工神经网络与近红外光谱分析

介绍了人工神经网络的原理、结构、算法和研究进展,以及该方法在近红外光谱分析中的重要地位和应用。     

Research on Growth Behavior of Embryos for Bovine and Murine on Primary Murine Embryos Fibroblast Cell Feeder Layer

The difference in growth behavior between bovine embryos and murine embryos was studied on PMEF(primary murine embryos fibroblast)feeder layer. The results showed as follows: With embryos having attached, bovine embryonic trophoblast formed a transparent membranous structure covering on inner cell mass (ICM), however, murine embryonic trophoblast formed disc structure. Bovine embryos formed four kinds of ICM colonies with different morphology including the mass-like, the net-like, the stream-like and the mixture-like colonies. Compared with Murine ICM, the bovine ICM grew more fast. So, the bovine ICM was passaged at first after a culture of approximately 5 - 6 days in vitro, but murine ICM was passaged at first after an attachment of 3 - 4 days on PMEF feeder layer. The mixture colonies of bovine ICM differentiated very early, while the others differentiated very late. Most ICM-like mass of Bovine grew in a defined spot, but bovine ICMs like stream and ICMs like net proliferated fast and dispersed quickly. We found that the single blastomeres derived from late bovine morula and late murine morula formed sub-blastophere; moreover, the bovine ICM cell would differentiate rapidly if the trophoblast was removed.     

哈尔滨太平国际机场春季鸟类的群落结构

1999年和2000年3月-5月，对哈尔滨太平国际机场及附近的旱田，水田，树林，水域，草甸和村屯6种生境春季鸟类群落的相似性及鸟类群落结构进行了调查，共记录鸟类96种，分属12个目，34个科，其中树林生境中密度及种类最多，分别为227.27只/10hm^2，54种，旱田生境中的密度及种类最低，分别为64.91只/10hm^2。27种，水田和水域的相似性系数最高，为73.97%。水域与村屯最低，为10.69%，树林生境的多样性及均匀性最高，分别为0.9437,5.4312，水域均匀性最低，为0.3891。春季对飞机飞行安全可能造成较大威胁的鸟类有5种，即毛脚Kuan(Buteo lagopus)，金斑Heng（Charadrius Placidus)，扇尾沙锥（Gallinago gollinago)，长耳Hao（Asio otus)，小嘴乌鸦（Coruvs corone)。     

Research on Isolation and Clone of Embryonic Stem Cell-Like in Bovine

Bovine embryonic stem cell would be invaluable for researching the aspect of animal cloning, production transgenic animal and discussion of gene function in vitro. With the object of establishing an effective culture system for isolation and clone of bovine pluripotent stem cell, we cultured bovine embryos and mouse embryos including morula blastula and hatached blastula and obtained animal ICM on Primary marine embryonic fibroblast (Primary murine embryonic fibroblast, PMEF) feeder layer with tissue medium(DMEM supplemented with 15ml/100ml NBS ,0.1μmol/L Na2SeO3, 0. 1mmol/L β-mercaptoethanol, 1 000ng/ml LIF,10 ng/ml IGF, 1mmol/L necessary amino acid and 1mmol/L L-glutamine), then, we obtained mouse ICM and bovine ICM. Moreover, we isolated and cloned the 6 passage bovine ES like cells(12 cell lines) and 9 passage marine ES like cells (52 cell lines) deriving from bovine ICM and murine ICM respectively on the feeder layer of PMEF by disaggregating ICM and ES cell clones of bovine and murine into smaller clumps through digesting with 0. 125g/100ml trypsin and 0.02g/100ml EDTA and scattering with a glass needle. The pluripotency of both murine and bovine ES like cells was identified with morphological character, histochemistry identification, karyotype analysis and differentiation of ES cells in vitro or in vivo. This result showed that bovine embryonic stem cell and murine embryonic stem cell had developmental pluripotency.     

埋植Revalor对秦川阉牛肉用性能的作用

 将40头约13月龄的秦川阉牛按体重分为10个单位组，每组4头，其中1头作对照，3头埋植Pevalor，经过89天肥育试验后进行屠宰和肉脂品质测定。结果表明，Revalor显著降低了血清脲氮含量，极显著提高了血清谷草转氨酶活性；使得秦川阉牛日增重和饲料报酬分别提高19.2%和17.8%，增加了胴体瘦肉量，减少了脂肪沉积；提高了胴体蛋白含量，明显改变了脂肪组织的脂肪酸组成，但对肌肉中17种水解氨基酸含量无明显影响。Revalor对秦川阉牛行为有一定的不良影响，使得争斗和爬跨活动频繁，逃跑距离增大，但并不严重，不足以构成饲养管理上的困难。     

MDH和G6PD同工酶在家鸡个体发育中的表现特征

采用不连续缓冲系统的聚丙烯酰胺凝胶电泳法(PAGE法)结合组织特异性染色技术,对家鸡不同发育阶段和不同组织器官的苹果酸脱氢酶(MDH)和葡萄糖-6-磷酸脱氢酶(G6PD)同工酶进行了测定.结果表明,MDH同工酶在家鸡体内既有阶段发育特征,又有组织器官特异性表现,且s-MDH和m-MDH的分布和表达的量上有较大差别,表现在s-MDH在谱带多少、组织分布普遍程度和酶活性高低上都强于m-MDH.认为MDH同工酶在家鸡体内主要参与该组织器官的脂肪代谢.G6PD同工酶在家鸡未成年之前各发育阶段和各组织器官只呈现酶谱痕迹,成年之后仅在肝、心、肾、睾丸、胸肌中出现1～2条谱带,显示出分布的发育阶段和组织器官局限性.