减数分裂的

The authors proposed that heterochromatin change in genome might play an important role in balancing the germplasms between maize and its distant relatve after cross and parthenocarpy.

这种变异不仅存在于表型不稳定的早代孤雌系中，而且还存在于表型稳定的高代系中，造成这种变异的原因可能是因为远缘种质的引入影响到遗传平衡进而引起染色体发生结构重排并引起染色质的变化，这种变化与玉米染色体组中非同源染色体间存在的同源片段和因此造成的减数分裂过程中非同源染色体配对有着直接的关系。

This result suggests that cytomixis occurred at synizesis stage may produce some kind of stress which results in activation of retrotransposon to insert into a new locus, or/and breakage rearrangement at the site of retrotransposon in genomic DNA, that both can be detected by fingerprinning.

分析认为在兰州百合减数分裂前期Ⅰ的凝线期时，由于染色质的胞间运动造成对基因组DNA的胁迫，导致了逆转座子del的激活，所插入的位点序列即为所检测到的特异片段；或者是由于染色质的胞间运动造成染色体的断裂重排。

1Unequal number of univalents with decreased degree of synapsis and lagging chromosomes occurred in meiosis.The abnormal chromosomal behavior correlated with heterogenicity gave rise to unequal allocation of homogenous chromosomes to daughter cells and resulted in the deletion of functional chromosoms,thus led to the occurence of a certion proportion of aborted pollens.(2)The interaction between genetic imbalance and such environmental factors as temperature,etc.,further drew forth physiological and even structrural imbalance,with abnormal development of pollen mother cells and tapetal cells,and consequently resulted in no or very few production of pollens.The difference in the interaction between environment and genotype reflected on the unstability of pollen abortion in different years.

1在减数分裂中有数目不等的联合程度较差的单价体以及落后染色体出现，这种与异质性相关的染色体行为异常，导致同源染色体向子细胞的不均衡分配，造成具功能染色体的缺失，从而引起毛白杨一定比率的败育花粉的产生；(2)遗传上的不平衡与温度等环境因子相互作用，进一步引发毛白杨生理乃至结构上的不平衡，花粉母细胞和绒毡层细胞发育异常，从而造成不产粉或产粉较少；环境与基因型互作的差异性导致了花粉败育的年度不稳定性。

The results showed that the rates of mature oocyte were 75.2％, 73.1％, 69.8％, 63.5％and oocyte at telophase of MI were 16.3％, 15.9％, 16.9％, 27.0％, respectively. The rates of maturation of oocytes cultured in TCM199 with serum, EGF and TGFαwere significantly higher than that of with BSA team (P＜0.05) and the number of oocyte stayed at telophase of MI in TCM199 with serum, EGF and TGFαteam were significantly less than that with BSA team(P＜0.05); Significant higher rates (66.6％, 66.6％, 73.6％) of normalα-tubulin distribution in oocytes cultured in TCM199+ serum, EGF and TGFαwere compared to that of TCM199+BSA(43.3％)(P＜0.05). The rates of oocyte with cortical granules in cortex were 58.8％, 33.9％, 54.7％and 47.9％respectively, there was significant difference between oocytes cultured with serum, EGF and BSA(P＜0.05). In conclusion, TGFαand EGF can promote the oocyte nuclear transition from telophaseⅠto metaphase of meiosisⅡ, and improved the expression and distribution ofα-tubulin during the ovine oocytes maturation; EGF and serum could promote oocyte cytoplasm maturation. The results suggested that EGF and TGFαmight substitute some substance in serum to improve the quality of oocyte nucleus maturation in vitro, but EGF might be more functional than TGFαto promote the maturation of ovine oocyte ooplasm.

三、EGF和TGFα对卵母细胞成熟的影响未成熟卵母细胞分别在TCM199基础培养液+血清、TCM199基础培养液+BSA+EGF、TCM199基础培养液+BSA+TGFα和TCM199基础培养液+BSA四组成熟培养系统中成熟培养，22小时后上述各组卵母细胞的核成熟率分别为75.2％、73.1％、69.8％、63.5％，处于第一次减数分裂末期的比率分别为16.3％、15.9％、16.9％、27.0％，在添加血清、EGF、TGFα各组中核成熟率显著高于其它各组(P＜0.05)，处于末期的比例明显低于其它各组(P＜0.05)：添加血清、EGF、TGFα各组在a-Tubulin蛋白的分布与表达上(66.6％、66.6％、73.6％)明显高于BSA组的正常率43.3％(P＜0.05)；各组CG发生迁移较好的卵母细胞的比率分别为58.8％、33.9％、54.7％、47.9％，血清组和添加EGF组CG迁移至皮质区的比例明显高于仅添加BSA处理组(P＜0.05)。

In order to obtain viable tetraploids, which remains a major challenge worldwide, research on spindle organization and chromosome behavior was carried out mainly in zhikong scallop, Chlamys farreri, a typical commercially important species which is being cultured in North China Sea. Immunofluorescent technique and laser scanning confocal microscopy has been developed for observation of both microtubule organization and chromosome segregation. Orcein squash method was also used for chromosome observation. A series of complicated configurations of the meiotic spindle and associated patterns of chromosome segregation, including tripolar and seperated bipolar segregation, were found in developing eggs following the inhibition of the first polar body.

为了攻克可存活四倍体人工培育技术的国际性研究难题，本研究选取了我国北方海区的典型经济贝类栉孔扇贝为主要研究对象，建立了一套免疫荧光染色和激光扫描共聚焦显微技术，结合使用染色体地衣红压片观察技术，对第一极体受抑制的受精卵的减数分裂纺锤体装配、染色体分离动态进行了研究，发现了一系列特殊的纺锤体装配及相应的染色体分离行为，包括三极分离、独立二极分离等分离类型，从亚细胞水平上阐明了四倍体形成的细胞学机理。

The rice reductional division gene coded protein is the protein having SEQ ID No.2 amino-acid residue of the sequence table, or it is the protein derived from SEQ ID No.2, having the activity same as the sequence of the SEQ ID No.2 amino-acid residue, in which protein, SEQ ID No.

水稻减数分裂基因编码的蛋白，是具有序列表中SEQ ID №：2氨基酸残基序列的蛋白质，或者是将SEQ ID №：2的氨基酸残基序列经过一个或几个氨基酸残基的取代、缺失或添加且具有与SEQ ID №：2的氨基酸残基序列相同活性的由SEQ ID №：2衍生的蛋白质。

The result is consistent with previous studies. Whereas, tapetal cells of sterile anthers were disintegrated since tetrad cells were disjoined, indicating that disintegration of tapetal cells is earlier occurred in sterile anther than that in fertile anther. DNA ladder revealed that the cleavage of nuclear DNA into oligonucleosome-sized fragments to

结果表明，在花粉母细胞减数分裂后的四分体解离时期，不育花药的绒粘层细胞较可育花药提前开始裂解；在不育系S-Mo17rf3rf3花药和花粉S-(rf3)中均明显出现PCD过程的DNA片段化以及线粒体细胞色素C外渗的现象，证明了玉米CMS-S的花粉败育与花药绒粘层细胞的提前凋亡和小孢子细胞的细胞程序性死亡有关。

Molecular studies have identified some genes participating in this process, including those regulating anther cell division and differentiation, controlling male meiosis, supporting pollen development, and promoting anther dehiscence.

分子生物学的研究已经发现了一些参与这一过程的基因，包括控制花粉囊组织的分化、小孢子母细胞的减数分裂、小孢子的发育和花药的开裂等。

Hytivus. Although chromosome number of all materials studied was counted to be 2n = 38, the difference in meiotic behaviors between individuals of first selfed progenies were observed, which indicated the difference in the degree of diploidization.

虽然染色体记数的结果表明所有单株的染色体数目都为38条，但是花粉母细胞的减数分裂行为在单株间的细小差异也被观察到了，这表明各单株间存在较小的二倍化程度的差异。

Pig oocytes cultured in vitro for some time were inseminated by frozen–thawed ejaculated sperm. At specified times after insemination, sperm penetration, cell cycle progression and mitogen-activated protein kinase phosphorylation were evaluated. It was shown that:(1) oocytes at various maturational stages could be penetrated by sperm;(2) sperm penetration did not affect meiotic cell cycle progression;(3) sperm penetration of germinal vesicle oocytes and maturing oocytes did not alter MAPK phosphorylation; and (4) when premetaphase I and metaphase I oocytes, in which MAPK was activated, were fertilised, no evident MAPK dephosphorylation was detected as in metaphase II oocytes.

不同成熟阶段的猪卵与精子融合后体外培养发现：(1)不同成熟阶段的猪卵母细胞都可被精子穿透；(2)精子穿透不影响减数分裂细胞周期进程；(3)精子穿透GV期卵母细胞和正在成熟的卵母细胞不改变MAPK磷酸化：(4)已受精的前中期I和中期I卵母细胞的MAPK有活性，MAPK不像MII卵母细胞那样受精后发生磷酸化。

The labia have now been sutured together almost completely.The drains and the Foley catheter come out at the top.

此刻阴唇已经几乎完全的缝在一起了，排除多余淤血体液的管子和Foley导管从顶端冒出来。

To get the business done, I suggest we split the difference in price.

为了做成这笔生意，我建议我们在价格上大家各让一半。