牛细胞核移植试验初报

体外成熟培养（ＩＶＭ）２３－２４ｈ的牛卵母细胞，去核后用８０Ｖ／ｍｍ，４０μｓ电激活２次（Ｉ组）或不激活（Ⅱ组），然后注入８－３２细胞期体外受精（ＩＶＦ）牛胚胎的卵裂球，再用８０－１００Ｖ／ｍｍ，４０μｓ电激两次诱导卵母细胞与卵裂球融合，两组的融合率（６２．８％与６５．１％）和卵裂率（５５．４％与５１．９％）无显著差异（Ｐ〉０．０５）。全部４１２枚重组卵电激后的融合率是６３．８％（２６３／４１２）     

鲶卵巢发育组织学的初步研究

以鲶卵巢为材料，研究了卵巢和卵母细胞发育的形态结构特点。鲶卵巢的发育划分为６期，其卵母细胞相应地划分为６个时相，第一时相的卵母细胞呈原始分化状态，细胞外具一层细胞质膜，第二时相卵母细胞外不仅具质膜，而且还有滤泡膜和结缔组织膜。第三和第四时相的卵母细胞分化明显，由散在的卵黄沉积逐渐形成大的卵黄颗粒。第四时相卵母细胞具有漏斗状的精孔及椭圆形的精孔细胞。第五时相和第六时相分别为卵子形成和退化吸收时相。     

大熊猫（Ailuropoda Melanoleuca）卵巢的年龄变化

对比观察了5只不同年龄大熊猫(包括青年、中年和老年)的卵巢皮质石蜡切片。可见皮质结构有较大的年龄变化。主要表现在:性成熟后,卵巢皮质的厚度随年龄的增长有减薄的趋势。成年的各级正常卵泡数量较少,初级和次级的更少;闭锁卵饱和间质腺较多,并呈现出随年龄增长而增多的动向。老年卵巢结构变化明显,皮质纤维化,卵泡全部消失,仅有较多囊泡,小动脉管壁增厚,管腔变小。老年卵巢的外形、体积和重量等方面与成年之间未见明显年龄变化。     

小鼠口服猪卵透明带DNA避孕疫苗pVAX1-pZP3a的抗生育研究

目的：评价口服卵透明带DNA避孕疫苗pVAX1-pZP3a壳聚糖纳米微粒诱发的黏膜免疫反应、抗生育作用和对卵巢结构的影响，探讨用黏膜免疫避免卵透明带抗原免疫引起卵巢功能紊乱的可行性。方法：制备pVAX1-pzP3a壳聚糖纳米微粒，10只昆明系小鼠口服免疫，第3周和第6周分别加强免疫一次，剂量为O．5ml／只，含pVAXl-PZP3aDNA 50μg；对照组10只雌小鼠口服相同剂量不含pVAX1-pZP3a的壳聚糖。免疫前和免疫后隔周取小鼠血清、阴道冲洗液，用ELIASA法检测抗pzP3 IgA和IgG。首次免疫后第12周雌雄合笼交配，统计雌鼠怀孕情况；解剖取出双侧卵巢，制作石蜡切片，光镜观察卵巢病理学变化。结果：免疫组80％小鼠的血清和50％小鼠的阴道冲洗液可检测到抗pzP3 IgA，反应强度与持续时间有明显的个体差异；免疫组5只小鼠未怀孕，对照组全部怀孕，抗生育效果与合笼时抗pzP3 IgA反应有关；免疫组未怀孕小鼠卵巢组织结构与免疫组怀孕小鼠及对照组小鼠无差别。结论：口服pVAX1-pZP3a壳聚糖纳米微粒免疫小鼠能诱发生殖道黏膜免疫反应，发挥抗生育作用，对卵巢组织结构没有影响。黏膜免疫是克服卵透明带抗原免疫引起卵巢功能紊乱的一种值得深入研究的方法。     

Effective strategy of the overwintering of semiaquatic bugs: overwintering of Velia caprai (Heteroptera: Gerromorpha: Veliidae)

Overwintering of Velia caprai was studied during the winter months 2006–2007 in the area of South Bohemia (Czech Republic) by (1) field phenological observations and samples, (2) study of artificially established experimental cohorts in an unheated glasshouse, and (3) auxiliary experiments in a laboratory. Velia caprai has a unique way of overwintering within the gerromorphan bugs that is rare among insects generally; it can overwinter in both an adult and an egg stage. Most females reach sexual maturity before overwintering, mate with mature males, overwinter actively on the water surface and lay eggs during the winter. The dormant eggs can be induced to hatch by increasing temperatures. Winter oviposition can be interpreted as a sign of a risk‐spreading reproductive strategy. The overwintering of both adults and eggs provides a chance to adapt to changes in the local environmental conditions and could be an important determinant in broad variability of life‐history traits.     

RNA-splicing endonuclease structure and function

The RNA-splicing endonuclease is an evolutionarily conserved enzyme responsible for the excision of introns from nuclear transfer RNA (tRNA) and all archaeal RNAs. Since its first identification from yeast in the late 1970s, significant progress has been made toward understanding the biochemical mechanisms of this enzyme. Four families of the splicing endonucleases possessing the same active sites and overall architecture but with different subunit compositions have been identified. Two related consensus structures of the precursor RNA splice sites and the critical elements required for intron excision have been established. More recently, a glimpse was obtained of the structural mechanism by which the endonuclease recognizes the consensus RNA structures and cleaves at the splice sites. This review summarizes these findings and discusses their implications in the evolution of intron removal processes. Received 24 August 2007; received after revision 24 November 2007; accepted 27 November 2007     

激素对长角血蜱生殖周期中生化成分的影响

在长角血蜱雌虫的不同生理时期测定其卵巢和脂肪体中ＲＮＡ，ＤＮＡ以及总蛋白含量，发现随着雌虫生殖的进展，卵巢和脂肪蹋体中上述物质的含量，在产卵前持续增加的临产卵，产卵后开始下降，且脂肪体中上述物质含量的升降快于卵巢，饱血后２ｄ，点滴２０－羟基蜕皮酮（２０－Ｅ）或法尼醇，发现：每蜱１，５μｇ２０－Ｅ能增加卵巢中核酸和总蛋白的含量：每蜱１００，５００μｇ法尼醇则显著增加ＲＮＡ，ＤＮＡ和总蛋白的含量，对脂     

兰栲泡桐未授粉子房胚状体的形态发生

本文报导了兰栲泡桐(paulownia elognta S.T.Hw)未授粉子房胚状体的形态发生。未授粉子房在BA、KT、Zt、IAA.2.4-D不同配比和浓度的Ms培养基上对胚状体的发生均有作用,其中BA1mg/L,IAA0.5mg/L的诱导频率为80%,Zt1mg/L,2.4-D1mg/L对胚状体的生长发育有良好作用。胚状体发生于胎座表层启动的胚性细胞,当胚状体转移到不加激素的培养基上,能分化成完整的植株。胎座的胚性细胞经继代培养能保持较长时期的分裂能力。实验中还观察到未去花柱的未授粉子房有利于愈伤组织的诱导;去花柱的未授粉子房则有利于胚状体的形成。     

蝇类卵巢染色体制备的新方法

以羽化后未交尾的雌性麻蝇为活体材料,通过“Feulgan预染——显微解剖悬液铺片——Giemsa复染法”获得形态良好、分散适中、着色清晰的卵泡细胞有丝分裂中期染色体标本。本法材料性别来源明确,对蝇类性染色体鉴定的准确性有重要意义。     

牛卵母细胞的采集方法和卵巢贮存条件对其体外成熟的影响

比较了抽吸法和剖切法取得屠宰奶牛卵巢的可用卵母细胞数,并探讨了在卵巢运输过程中温度和时间对卵母细胞成熟率和卵裂率的影响.从屠宰场收集奶牛卵巢158个,用抽吸法抽取了96个卵巢,平均每个卵巢收集可用卵母细胞8.04枚(772枚/96卵巢);用切剖法切割了62个卵巢,平均每个卵巢收集可用卵母细胞18.89枚(1171枚/62卵巢).统计分析证明,两种采集方法获得的可用卵母细胞数差异极显著(p<0.01).将屠宰牛卵巢分别置于20℃～29℃和30℃～38℃的生理盐水中,在6h内收集到卵母细胞的成熟率和卵裂率分别为53.8%、31.7%和63.3%、34.3%,两者之间的差异均不显著(p>0.05).在30℃～38℃温度下,屠宰牛卵巢保存时间超过6h时,卵母细胞的成熟率和卵裂率显著下降,分别为36.1%和0%.与小于2h和2～6h相比差异极显著(p<0.01).