牛早期胚胎性别鉴定的PCR方法研究

探讨了ＰＣＲ法鉴定牛早期胚胎性别时所用的引物,反应缓冲液中Ｍｇ２＋浓度,循环反应的次数及可能造成污染的各种因素对性别鉴定结果的影响．并对１８个胚胎进行了性别鉴定,移植３８枚性别鉴定后的胚胎,成功产下２头与预测性别一致的牛犊,胚胎性别可鉴率为９４．１％,预测性别符合率为１００％．     

青枯菌胞外多糖和酶对花生细胞POD及CYT的影响

用野生型青枯菌(fy7)及其胞外多糖缺失型(APT)和胞外蛋白缺失型(DF7)分别作用于青枯菌易感花生品种鄂花4号和抗性品种中花2号的悬浮培养细胞,等电聚焦分析处理后的花生细胞的过氧化物酶(POD)、酯酶(FAST)和细胞色素氧化酶(CYT)的变化．与对照组相比,fy7诱导12h时鄂花4号的3种酶都有变化,24h时只有中花2号有新POD带出现．APT诱导12h时只有FAST有变化,24h时POD和cYT均有较显著变化．DP7诱导12h时只有FAST有变化,24h时只有抗性细胞有新POD带出现．     

农杆菌介导的花生遗传转化体系的初步研究

应用花生胚小叶再生体系,以农杆菌介导法对质粒上的基因转化进行初步探讨.通过对影响基因转化的各因素,如抗生素的筛选压、共培养时间、AS的影响、及外植体取材方式等进行研究,结果发现:外植体与农杆菌在加有AS(100μmol/L)的改良MS液体培养基中共培养4 d后,先进行10 d的恢复培养,继而转入加有Hy(25 mg/L)和Cef(200 mg/L)的抗性筛选培养基中进行筛选培养40～50 d,后转入含Hy(20 mg/L)的分化培养基中分化,3个月后在首批材料中得到6个再生植株,经PCR检测,有1株显示了800 bp的GUS基因核酸片段,初步证实了此转化体系合理有效.     

石墨炉原子吸收法测定黑花生中的硒

该文以转基因食品黑花生为研究对象,针对硒易挥发的特点,建立了高压密闭消解-石墨炉原子吸收光谱法测定黑花生中总硒含量的测定方法.研究表明,HNO3-H2O2可使样品达到最佳消解,以Pd(NO3)2+Mg(NO3)2为基体改进剂,最佳灰化温度和原子化温度分别为500 ℃和2 000 ℃.在优化实验条件下,该方法测定硒的线性...     

Precambrian phosphatized embryos and larvae from the Doushantuo Formation and their affinities, Guizhou （SW China）

Weng＇an phosphates of the Precambrian Doushantuo Formation, Guizhou （southwestern China） preserve a large number of exquisite biological structures, which are mostly micro-spherical and represent seaweeds, acritarchs and developing eggs related to various groups of metazoans. Here is a report of a variety of developing eggs and larvae, which are most probably of Cnidarian affinity. The eggs examined in the study are composed of early cleavage embryos and two-layered gastrulae. The early cleavage embryos are radial and total cleavage with equal-size blastomeres. The gastrulae mostly bear a large archenteron, which is filled with yolk-degrading organic matter. Ovoid to fusiform planula-like larvae identified in thin sections under light microscope are mostly mouthless and their gastrovascular cavity is filled with possible yolk-degrading organic matter. They are likely representatives of non-feeding larva. The uncommon planula-like structures are hollow, with each having a mouth-like structure on its narrow end. We interpret them as feeding larva. Study of these embryos with possible Cnidarian affinities shed new insight on the origin of metazoans.     

早期胚胎玻璃化冷冻保存技术研究进展

胚胎冷冻技术是胚胎移植真正走向商业化应用的关键环节,并受到广泛的关注,而玻璃化冷冻不仅具有操作时缩短、而且方法简易、不需要昂贵的设备,容易在生产中推广使用,因而日益受到人们的重视。本综述阐明了胚胎玻璃化冷冻原理,讨论了抗冻保护剂及其选择原则,比较了玻璃化冷冻技术各种方法及其优缺点,分析胚胎玻璃化冷冻的影响因素,展望了玻璃化冷冻技术的应用前景。     

文昌鱼早期发育中两种碱性磷酸酶的表达

以BCIP为底物研究了碱性磷酸酶在文昌鱼胚胎和幼体中的表达图式.在囊胚、原肠胚和神经胚早期(12～13小时)未检测到碱性磷酸酶的特异性表达;到神经胚中期(15小时,约6个体节),碱性磷酸酶在每一体节的中部开始表达,在胚胎中形成3～6个条纹;在18小时神经胚中,碱性磷酸酶在肌节中表达;到24小时在后部内胚层中也开始表达;在36～48小时幼体中,碱性磷酸酶在消化道中强烈表达,但在咽鳃区不表达,同时在肌节中仍有弱的表达.研究表明碱性磷酸酶可能在肌节的发育过程中具有一定作用.碱性磷酸酶在消化道中的表达可能与这一时期消化道开始行使功能有关.为了鉴定文昌鱼碱性磷酸酶的性质,还研究了L-苯丙氨酸对碱性磷酸酶表达图式的影响,结果表明文昌鱼至少存在两种碱性磷酸酶在消化道中表达的一种是肠型的,与脊椎动物碱性磷酸酶可能为同一类型;另一种主要在肌节中表达,可能是组织非特异性的碱性磷酸酶.     

Sexual difference in gonadal development of embryonic chickens after treatment of polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) are ubiquitous, persistent and lipophilic environmental endocrine disrupters that can be biomagnified in human and animals including birds and thus to affect reproductive functions. Poultry meat and eggs contain a great deal of fat and possibly concentrate higher PCBs and other environmental contaminants such as dichlorodiphenyl-trichloroethane (DDT). In order to identify the adverse effects of PCBs and possible sexual difference on chicken gonadal development, Aroclor 1254 was injected into fertilized Hyline chicken eggs before incubation. Four groups of eggs received yolk injection of either peanut oil as control, 1, 10 or 100 mg/egg of Aroclor 1254 as treatment group, respectively. After hatching the gonads were removed for histological examination. Testicular structure was apparently changed and exhibited dramatic decrease in area of the transverse sections (1 mg/egg, P＜0.01; 10 and 100 mg/egg, P＜0.001), diameter (10 and 100 mg/egg, P＜0.05) and relative area of the testicular tubules (10 mg/egg, P＜0.05; 100 mg/egg, P＜0.01). Most testicular tubules of the highest dose group degenerated and even disappeared. The differentiation of germ cells was retarded in all groups treated with Aroclor 1254. Some germ cells were irregular in shape, with vacuolated cytoplasm and hyperchromatism nucleus (pyknosis) in 1 and 10 mg/egg groups and almost all germ cells in 100 mg/egg group. In contrast, the area of the left ovarian transverse sections increased dramatically (10 and 100 mg/egg,P＜0.001), the ovarian cortex manifested a significant increment in thickness (1, 10 and 100 mg/egg, P＜0.001) and a higher number of oocytes was observed (1, 10 and 100 mg/egg, P＜0.001) in the female chickens treated with Aroclor 1254 compared with the control group. A few oocytes with vacuolated cytoplasm and hyperchromatic nucleus were also observed in ovarian cortex after PCBs exposure. These results showed that PCBs interfered with gonadal development with a sex-specific pattern and retarded differentiation of spermatogonia into spermatocytes but accelerated differentiation of oogonia into oocytes in the embryonic chickens.     

17400鲨鱼软骨血管生成抑制因子的纯化及生物学活性研究

采用盐酸胍抽提、膜超滤、丙酮分级沉淀、Sephadex-75柱层析和C₄反相高效液相色谱等分离步骤,从广东阳江鲨鱼软骨中纯化获得新的鲨鱼软骨血管生成抑制因子SCAI-c(SharkCartilageAngiogenesis In-hibitor-c,SCAI-c);SDS-PAGE电泳银染显示为一条带,根据蛋白质的相对迁移率计算,分子量为17400;它对鸡胚绒毛尿囊膜血管的形成具有显著抑制效应,并有明显的浓度依赖关系.SCAI-c与SCAI-a具有类似的生物学特征.     

乙二胺改性花生壳粉吸附阴离子染料的研究

以天然产物花生壳作为基质、环氧氯丙烷为交联剂、乙二胺为改性剂合成了一种新型吸附剂,用荧光体视显微镜、红外光谱、X射线光电子能谱分析了其表面结构.考察了吸附时间、温度、溶液pH值、染料初始浓度对吸附直接蓝（DB）和日落黄（SY）的影响.结果表明：此吸附剂于25℃,pH 2.0时对直接蓝和日落黄的最大吸附容量分别为129.1和135.2 mg.g-1,分别为未改性花生壳粉的5.6和4.8倍,吸附平衡时间为3 h.高酸度下吸附阴离子染料的结果表明：染料阴离子与花生壳粉表面质子化的氨基以静电引力实现吸附.用Langmuir和Freundlich模型拟合的结果表明：吸附为Langmuir单分子层化学吸附,吸附表观动力学为二级反应.