不减数分裂

To investigate whether the expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis is actually a temperature dependent event, in situ hybridization, Western blotting and immunohistochemistry analysis were used to study the expression of cdc2 and cyclin B1 in normal and cryptorchid testis. Results showed that heat would differentially hurt male germ cells in different developmental stages during spermatogenesis, especially the pachytene primary spermatocytes. Most of spermatogonia in contralateral cryptorchid testis were not harmed fatally by heat as yet, indicating that spermatogonia could resist to beat to a certain extent. In this case spermatogonia could develop to pachytene/diplotene primary spermatocytes, but they could not acquire the ability to complete the transition from mitosis to meiosis, and then appeared to go through apoptosis. Therefore, we could not find the descendants of meiosis: secondary spermatocytes and round spermatids, elongated spermatids and spermatozoon. The abdominal temperature had no significant influence on the transcription of cdc2 and cyclin B1 in the spermatogonia and pachytene/diplotene primary spermatocytes. In normal rabbit testis, cyclin B1 increased in the pachytene/diplotene primary spermatocytes before meiosis and reached its peak in the spermatids.

为了解精子正常发生过程中cdc2和cyclin B1表达的低温依赖性，我们利用原位杂交和免疫组化等方法，研究了正常和隐睾精子发生过程中cdc2和cyclin B1的转录和翻译调控活动，结果表明：（1）热对各阶段的雄性生殖细胞都有损害，粗线期的初级精母细胞尤为敏感，实验性隐睾内的精原细胞尚未完全受到"致命"影响，说明精原细胞对热有一定的耐受性，但即使成为粗线期／双线期初级精母细胞，却未能获得由有丝分裂过渡到减数分裂的能力，呈现不同程度的凋亡，所以在整个切片中找不到源自减数分裂的产物----次级精母细胞、圆形精子细胞，更谈不上长形精子细胞和精子的形成；（2）腹腔高温未明显地影响隐睾精原细胞和粗线期/双线期初级精母细胞中cyclinB1和cdc2的转录，说明高温并不是通过影响cyclin B1和cdc2的转录活动而导致生精过程阻断的；（3）正常兔睾丸组织中，〓在精原细胞和粗线期／双线期精母细胞中均有表达：cyclin B1蛋白在减数分裂前期的粗线期／双线期初级精母细胞中的表达量增加，于变态末期的精子细胞中达高峰。

They are often morphologically distinct from A chromosomes, being smallerand more highly heterochromatic in most cases. B chromosomes do not pair with Achromosomes, and they are inherited in a non-Mendelian way, exhibiting meiotic andmitotic instability and nondisjunction. However, B chromosome DNA is quiteidentical to the corresponding sequence on the A chromosome complement. So far afew B chromosome specific DNA sequence have been identified. Specific DNAsequences on B chromosome have been the attractive research area on Bchromosomes.

现已在千余种植物和近三百种动物中被发现。B染色体与物种中正常染色体不同：独立于整倍体基因组之外，减数分裂时不与A染色体发生联会和配对，细胞分裂后期不分离，非孟德尔遗传，富含异染色质，不含对宿主主要性状有影响的基因等。B染色体DNA的分子组成既与A染色体极为相似，具有A染色体DNA分子组成的一般特征：富含重复序列和转座成分，染色体三大功能组件DNA高度同源；又与之相区别，含有B染色体特异的DNA序列，这些DNA序列可以为探讨B染色体的起源和进化提供有价值的信息。

Purpuraristatus, the growth, fertility, chromosome configuration, EST isozyme etc. were analyzed in this paper. The results showed that the growth potentiality of (E. sibiricus×E. purpuraristatus) F2 and (E. purpuraristatus×E. sibiricus) F1 were much stronger than their parents, the plant height of the former was 143.2 cm. The whole plant was reseda, the latter was 129.7 cm. The spike nodding of two hybrids were in the middle of their parents, the anther was yellow; the pollen fertility was 0.02%~0.03%, seed set was 0; the average chromosome configuration of former pollen mother cell at PMC M Ⅰ was 6.90Ⅰ+14. 02Ⅱ, the latter was 7.82Ⅰ+13.59 Ⅱ, and lagging chromosome and bridge fragment were observed at meiosis anaphase Ⅰ the EST of the two hybrids F1 and their parents at tillering stage was some certain different in locus, number and intensity.

结果表明，正交F1和反交F1植株的生长势均很强，正交F1株高143.2 cm、全株浅绿色，反交F1株高129.7 cm、全株灰绿色；正、反交F1的穗型均呈双亲中间型，花药呈黄色，花粉可育率0.02%~0.03%，结实率为0，说明杂种高度不育；正交F1的花粉母细胞减数分裂中期Ⅰ平均染色体构型为6.90Ⅰ+14.02Ⅱ，反交F1为7.82Ⅰ+13.59Ⅱ，减数分裂后期丁有落后染色体和染色体桥等不规则现象；亲本及其正、反交杂种F1分某期幼叶的EST同工酶酶带的位点、数目和强弱均存在一定差异，可作为亲本及杂种在蛋白质水平识别的重要依据。

At time of 5mm length of alabatrum, the miosis in microsporecyte and the sex differentiation was found, thus in female flowers, pollen mother cell showed a abnormal meiose then the pollen cells gradually disintegrated, final, contabescence had taken, and in male flowers, the stamen normally developed.

在幼蕾长到5mm左右，即花粉母细胞开始减数分裂时，出现花性别的分化，雌花中雄蕊花粉母细胞不能进行正常减数分裂，进而花粉细胞逐步解体而导致雄蕊败育；雄花中雄蕊发育正常至性成熟。

Morphology of sexual reproduction abortion in'High Noon', a distant hybridization cultivar of tree peonies(P.delavayi var. lutea×P. suffruticasa), was systematically investigated with light microscopy and cross. The results indicated that:(1)The stamens matured earlier than the gynoecia and pollens dispersed at the early stage of anthesis but the rate of normal 2-celled pollens were merely 2.41%.

采用光镜和杂交等方法对牡丹远缘杂交一代品种'正午'有性生殖败育进行系统形态学观察发现：(1)雄蕊较雌蕊先成熟，初花期即散粉，正常2-细胞花粉仅占2·41%，且花粉在多种培养液中、在自身和其它两种柱头上均不萌发；柱头在谢花期大量分泌粘液，进入最佳授粉状态；(2)同一胚珠中多个大孢子母细胞减数分裂高度不同步，胚囊发育与受精延迟，部分胚乳游离核在细胞化时期分裂异常；(3)自花及品种内异花授粉不结实，天然授粉结实率为0·053‰~0·130‰。

In mixoploid plants, somatic cells with 2n=25~29 were most frequent except for a few haploid cells (2n=19) and chromosome doubling cells (2n=50~60). Abnormal chromosome behaviors were observed in pollen mother cells from mixoploid BI-1 and haploid, including chromosome bridges, laggard chromosomes, meiotic cycle asynchrony and unequal separation of chromosomes.

对混倍体植株BI-1和单倍体植株的花粉母细胞(Pollen mother cells，PMCs)减数分裂染色体行为观察发现，高频率出现染色体落后、染色体桥、染色体分裂周期不同步、不均等分离等异常染色体行为。

In conclusion, these results suggested that (1) the ageing-associated decline in fertility of female KM mouse was due to a decrease in both quantity and quality of oocytes;(2) the ooplasm from young mice did not correct the meiotic errors of aged mice, and the ooplasm from aged mice did not induce abnormal segregation of meiotic chromosome of young mice, indicating that meiotic anomalies found in the oocytes of aged mice might be related to nucleus or chromosomes and relevant factors;(3) a critical nucleocytoplasmic ratio was essential for normal maturation and segregation of meiotic chromosomes of oocytes and development to 2-cell embryos.

本研究结果表明：（1）昆明白小鼠与衰老相关的生育力下降是其卵母细胞数量减少和质量下降的综合结果；（2）年轻小鼠卵母细胞细胞质不能纠正老龄小鼠GV的减数分裂错误，老龄小鼠卵母细胞细胞质也不诱导年轻小鼠的GV发生减数分裂错误，老龄小鼠卵母细胞减数分裂异常很可能与细胞核或染色体及其相关因素有关；（3）关键的核质比对卵母细胞正常的成熟、减数分裂染色体分离及2-细胞期胚的发育是绝对必需的。

Thus it is obvious that the weak homology existedamong genomes A, B, D and 〓. However, the rare unreduced gemetes and near-unreduced ones with the loss of several chromosomes could be produced by the highlyunequtional division of univalents at the first meisis and the normal second division,which gave the F1 hybrid the partial fertility.

但通过第一次减数分裂时单价体的极不对称的分离及正常的第二次分裂，可形成少量未减数配子和丢失了少数几条染色体的近未减数配子，使杂种〓表现部分可育性。

The situation of abnormal development of male cells is as follows:microspore mother cell can't enter into meiosis because of intense vacuolation,shrink and disintegration of its cytoplasm;although vacuolated microspore mother cell can enter into meiosis,it can't form normal dyad and degenerate in the middle process;dyad and tetrad become vacuolated and can't develop normally;cytoplasm of microspore shrinks around the nucleus at the stage of central nucleus microspore,the shape of microspore is twisted into crescent or irregular shape,at last its cytoplasm and nucleus are disintegrated and crescent vacant microspore presents;nutritive substances can't be accumulated at the stage of vacuolated microspore,cytoplasm is disintegrated,and microspore turns into a big vacant pollen.

雄性细胞异常发育有几种情况：小孢子母细胞强烈液泡化，细胞质收缩解体，不能进入减数分裂；小孢子母细胞液泡化，虽能进入减数分裂，但不能形成正常二分体而中途退化；二分体、四分体细胞液泡化，不能进行正常发育；单核小孢子中央期，细胞质收缩包围核，小孢子形状扭曲呈月牙形或不规则形，最终细胞质和核解体而呈月牙形的空壳小孢子；单核液泡期的小孢子不能积聚营养物质，细胞质解体而成为大的空壳花粉粒。

The results showed that the varieties and activity of POD isoenzyme expression exist in difference in anther of male sterility line and maintainer in different development stage in sweet pepper and hot pepper. POD isozyme activity of anther was very low in meiosis stage in male sterility line of sweet pepper. There is a POD special band in meiosis and pollen mature stage in male sterility line of pepper respectively.

结果表明不育系与保持系，在花药发育的不同时期POD同工酶表达种类及表达活性之间存在差异，其中甜椒不育系在减数分裂期POD同工酶的活性非常低，辣椒雄性不育系在减数分裂期及花粉成熟期分别多一条POD特征带。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。