恒河猴群微卫星DNA多态性的分析

目的　确立一种对恒河猴群个体的遗传物质进行准确可靠、快速简便的遗传检测方法。方法　利用聚合酶链反应 (PCR)扩增技术对 2 0只恒河猴群个体间进行了DNA多态性的分析。结果　筛选出 9个微卫星DNA位点具有显著多态性 ,4个微卫星DNA位点没有多态性 ,还有 2个位点等位基因数目较少。结论　利用这些多态性微卫星位点建立一种对恒河猴群个体进行有效、准备可靠、快捷简便的遗传背景监测方法。     

绵羊GDF9和BMP15基因多态性检测

以绵羊GDF9基因FecG^H突变和BMP15基因FecX^B和FecX^G突变为候选基因,采用PCR—RFLP方法研究其在湖羊、夏洛来、陶赛特、萨福克、中国美利奴肉用多胎品系、中国美利奴羊和罗米丽羊7个品种中的多态性．结果发现,湖羊群体中存在GDF和BMP15基因的FecG^H和FecX^B突变,但发生率极低,分别为0．645％(2／310)和0．968％(3／310)：而其它品种中则没有发现GDF9和BMP15基因的相应突变．这一发现对于建立绵羊基因标记辅助选择方法具有重要意义．     

几种脊椎动物宽频带心电图波形与心电向量环特点的比较

对小鼠、家鸽、蟾蜍、鲫鱼4种脊椎动物宽频带心电图Ⅱ导联的波形特点及QRS额面心电向量环的位置、形态特点进行了比较研究。结果发现,(1)宽频带心电图Ⅱ导联QRS波群小鼠、蟾蜍、鲫鱼QRS波群的主波均向上,而家鸽的主波向下;(2)QRS波群时程(ms)小鼠88±09,家鸽365±14,蟾蜍790±110,鲫鱼283±57;(3)QRS心电向量环的位置家鸽的位于-90°～-180°象限内,这是家鸽心电图Ⅱ导联QRS波群主波向下的根本原因;小鼠、蟾蜍、鲫鱼的均位于0°～90°象限内,与它们的QRS波群主波向上相一致;(4)QRS心电向量环的形状;小鼠的QRS向量环较其它3种动物的要大,蟾蜍的最小。鲫鱼的不规则,有的呈三角形,有的呈“8”字形,还有的呈半圆形,这是导致鲫鱼的QRS波群出现较多切迹和扭挫的原因。     

抗淋巴细胞免疫球蛋白制品中热原处理

对热原不合格的抗淋巴细胞免疫球蛋白 (ALG)半制品再制条件进行了研究。将高热原的ALG半制品通过使用碱、酸以及A5 0处理后 ,细菌内毒素的含量明显降低 ,热原质经家兔和鲎试剂检测均合格 ,其生物学效价仍不低于 1 :4 0 0 0 ,而且它们的其它各项主要指标也都达到中国生物制品暂行规程的要求。这一试验结果表明碱、酸处理并辅以A5 0吸附是去除ALG制品中热原的一种有效方法     

南方鲇的营养学研究:饲料中大豆蛋白水平对消化率及摄食率的影响

以23.78±0.09g的南方鲇为实验对象,以Cr2O3作为测定饲料消化率的指示物,以大豆蛋白分别替代0%、13%、26%、39%、52%和65%的鱼粉蛋白,配制成6种等氮(粗蛋白48%)、等能(总能20KJ/g)的饲料,用于探讨饲料中大豆蛋白替代鱼粉蛋白的比例对南方鲇消化率及摄食率的影响。实验在27.5±0.02℃水温条件下进行6周,溶氧维持在5mg/L以上,光制为14L∶10D。结果表明,饲料中不同比例的鱼粉蛋白与大豆蛋白对南方鲇的消化率及摄食率均存在显著影响(P<0.05)。其中南方鲇对于物质、蛋白质、脂肪和能量的消化率随着大豆蛋白替代率的提高而逐步下降,当替代量为65%时,其消化率显著低于其余各组(P<0.05)。而南方鲇的摄食率均随着饲料中大豆粉添加量的升高而升高,当大豆蛋白替代鱼粉蛋白超过39%时,摄食率显著高于其余各组(P<0.05)。通过分析认为,消化率是限制南方鲇利用大豆粉的重要因素,而摄食率不是影响其利用率的主要原因。     

鲎试剂在抗淋巴细胞免疫球蛋白热原检测中的应用

报道了鲎试剂在抗淋巴细胞免疫球蛋白内毒素检查中的应用。在用鲎试剂检测细菌内毒素时 ,按中国药典的要求对鲎试剂灵敏度进行标定 ,并作干扰实验 (增强或抑制实验 ) ,然后用鲎试法与家兔法同时测定 15批抗淋巴细胞免疫球蛋白。结果发现三批鲎试剂的灵敏度标示值均正确 ,五批抗淋巴细胞免疫球蛋白半成品在最大有效稀释度 (MVD)时对试验无干扰 ,这两种方法测定结果的符合率达到 91.7%。从而表明鲎试法很有可能代替家兔法     

家蝇对拟除虫菊酯抗性机理研究进展

本文概述了家蝇对拟除虫菊酯的抗性机制 ,特别是结合我国室内培育的抗拟除虫菊酯家蝇品系 (Dec R和 2Cl R) ,探讨了Na+通道、神经递质释放、ATPase、蛋白质磷酸化等与家蝇Kdr抗性的关系 ,从多方面证明了神经敏感性降低是家蝇对拟除虫菊酯产生抗性的重要机制。     

Aspergillus Ficuum Phytase: Partial Primary Structure,Substrate Selectivity,and Kinetic Characterization

Purified Aspergillus ficuum phytase's partial primary structure and amino acid and sugar composition were elucidated. Determination of kinetic parameters of the enzyme at different pH values and temperatures indicated no significant alteration of the Km for phytate while the K_cmt was affected. The enzyme was able to release more than 512 of the total available P₁ from phytate in a 3.0 hr assay at 58°C, but the K_cmt dropped to 15Z of the initial rate. Substrate selectivity studies revealed phytate to be the preferred substrate. The pH optima of phytase was 5.0, 4.0, and 3.0 for phytate, ATP, and polyphosphate, respectively. The enzyme had varied sensitivity towards cations. While Ca^±± and Fe^±±produced no effect on the catalytic rate of the enzyme, Cu^±, Cu^±±, Zn^±±, and Fe^±±± were found to be inhibitory. Mn^±± was observed to enhance enzyme activity by 33Z at 50 μM. Known inhibitors of acid phosphatases e. g. L (±)-tartrate, phosphomycin, and sodium fluoride had no effect on enzyme activity.     

Biochemical and molecular identification of Xanthomonas translucens pv. undulosa causing bacterial leaf streak of wheat in Punjab,Pakistan

Xanthomonas translucens pv. undulosa, (Xtu.), causal agent of Bacterial leaf streak (BLS) of wheat, was characterised through pathogencity, hypersensitivity, biochemical and molecular assays. Fifty symptomatic leaves of wheat were collected from eight agro-ecological zones of Punjab out of which 25 were isolated and purified. Maximum incidence and severity in Faisalabad were followed by Multan and Rahim Yar Khan. The pathogen isolated from diseased leaves was identified on the basis of colonies pattern, colour, biochemical and pathogencity test as X. translucens pv. undulosa and confirmed its pathogencity through pathogencity test. For molecular characterization, the bacterial 16S–23S rDNA spacer fragments were amplified by PCR with conserved primers (C1 and C2) and then in combination with specific primers (T1 & T2). 300?bp product amplified by C1 and C2 primer pair confirmed the presence of Xanthomonas, while specific primers T1 and T2 amplified a product of 200?bp, confirmed the presence of X. translucens pv. undulosa. This work will be quite helpful for wheat pathologist and breeders for future management strategy for this disease.