多胚水稻APⅢ受精前后反足细胞空间分布的变化

应用显微技术对多胚水稻(Oryza sativa L.)ApⅢ开花前后的幼嫩颖果进行了观察.结果表明:在胚囊分化和发育过程中,反足细胞的数目和分布呈现出多样性,即在胚囊形成的早期,3个反足细胞位于合点端,在成熟胚囊中,绝大多数的反足细胞增殖形成由4至20多个细胞组成的1或多个细胞团,其位置也转移到胚囊的中上部一侧;少数的出现在珠孔端与卵器相邻,或镶嵌在卵器细胞之间;极少数细胞团从胚囊中部向珠孔或合点端延伸.在多胚水稻ApⅢ中观察到当反足细胞与卵器相邻或镶嵌在卵器细胞之间时,伴随着一些卵器或者幼胚(在形成了胚的胚囊中)解体的现象.此外,对多胚水稻反足细胞的功能进行了讨论.     

五唇兰双胚囊的观察

应用石蜡切片法对五唇兰(Dorrtis pulcherrima Lindl.)的胚囊发育过程进行了观察,结果表明:五唇兰的胚囊发育类型为双孢子葱型,胚珠通常含单胚囊,也形成约1%的双胚囊.双胚囊胚珠和正常发育的胚珠一样呈倒生型、具薄珠心、两层珠被,但胚珠横轴与纵轴的比值是正常胚珠的1.3-2倍,同一胚珠内的两个胚囊发育不一定同步.     

可可茶子叶培养中体细胞胚状体形成及植株再生

用含有０．５ｍｇＬ－１２,４－Ｄ或０．５ｍｇＬ－１２,４－Ｄ加２ｍｇＬ－１ＰＣＰＡ的ＳＨ培养基（含ρ（蔗糖）＝３％）培养可可茶的未成熟子叶,２周后即可从合子胚的下胚轴诱导出胚状体,５～７周后可以从子叶表皮直接诱导出胚状体．在含０．２ｍｇＬ－１２,４－Ｄ的培养基中,子叶外植体在培养４周内即能分化出胚状体且分化频率较高．培养１５周后把培养物转接至含２ｍｇＬ－１ＢＡ加上０．２ｍｇＬ－１ＩＢＡ的培养基中（含ρ（葡萄糖）＝２．５％）可以诱导出“种子状胚”、“芽状胚”和“杯状胚”,并可使“种子状胚”和“芽状胚”转化成苗．另外,还可诱导出丛芽并使丛芽转化成无根苗．若把“芽状胚”转移到含５ｍｇＬ－１ＧＡ－３和１ｍｇＬ－１ＩＡＡ的培养基中,“芽状胚”转化成无根苗的频率较高．     

巨峰葡萄大孢子发生和雌配子体发育过程的研究

巨峰葡萄子房２室，每室具２个胚珠。胚珠倒生，具两层珠被，胚珠发育属厚珠心型。大孢子母细胞减数分裂形成４个呈线形排列的大孢子。只有合点端１个大孢子发育成胚囊，单核胚囊经３次有丝分裂形成八核胚囊，成熟胚囊内具７个细胞。巨峰葡萄胚囊发育属蓼型。大孢子和雌配子体发生略迟于小孢子和雄配子体，雌雄配子体均在开花前完成发育。     

秦艽胚珠发育中淀粉动态的研究

应用树脂薄切片的甲苯胺兰Ｏ－ＰＡＳ反应结合苏木精整体染色法，对秦艽胚珠发育过程中淀粉动态进行了研究，结果如下：胚珠发育早期，其任何部位均未见淀粉料，稍后首先在合点区出现淀粉粒，再从合点向珠孔端逐渐扩大分布范围，开花前，珠被细胞中出现淀粉积累的两个高峰：大孢子母细胞时期；成熟胚囊时期，珠被细胞中淀粉粒增长迅速，数量多，个体大。胚囊成熟时，卵细胞内，次生核周围也积累许多淀粉粒。受精后，珠被及胚囊内淀粉     

茴香原生质体培养研究

以茴香（ＦｏｅｎｉｃｕｌｕｍｖｕｌｇａｒｅＬ．）幼苗茎切段在ＭＳ附近２，４－Ｄ１ｍｇ／Ｌ、６－ＢＡ０．５ｍｇ／Ｌ的培养基上诱导产生愈伤组织，经４～５次继代后形成胚性愈伤组织。将胚性愈伤组织转至ＭＳ＋ＮＡＡ１ｍｇ／Ｌ＋２，４－Ｄ０．５ｍｇ／Ｌ＋６－ＢＡ０．２５ｍｇ／Ｌ的液体培养基中培养，形成胚性细胞悬浮系。悬浮细胞在含有１．５％纤维素酶、１％果胶酶、０．５％蜗牛酶的混合酶液中酶解得到大量的原生质体，原生质体用修改的ＫＭ８Ｐ培养基中做液体浅层培养。２天后细胞发生一裂，两个月后形成０．５～１ｍｍ大小的小愈伤组织，转入含琼脂糖的固体培养基中３周后形成２～３ｍｍ的愈伤组织     

蚕豆胚囊人工分离技术研究

蚕豆胚珠在含4％果胶酶，1．5％半纤维素酶，1％葡聚糖硫酸钾，1％CaCl2和10％甘露醇的培养基中（PH5．7），30℃下保温12小时，胚囊得体约20．3％，先用脱壁剂振荡处理除去珠被角质层，再用上述培养基培养8小时，可得胚囊本37．8％，用染色法和酶法证明胚囊具有活性，表明除去角质层可缩短酶解时间，并提高同步性。     

蛇床愈伤组织的形态发生及植株再生

蛇床幼茎外植体在ＭＳ＋２，４－Ｄ２ｍｇ／ｌ＋ＫＴ０．２ｍｇ／ｌ培养基上形成淡黄绿色松软状愈伤组织。愈伤组织在转入培养基ＭＳ＋ＮＡＡ０．２ｍｇ／ｌ＋２Ｔ０．８ｎｇ／ｌ以后分化出不定芽，在１／２ＭＳ＋ＩＡＡ２ｍｇ／ｌ培养基中可产生不定根，进而发育成为完整植株。愈伤组织在ＭＳ＋２，４－Ｄ０．２ｍｇ／ｌ＋ＺＴＺＴ０．４ｍｇ／ｌ培养基中继代３～４次以后，再转入ＭＳ＋ＮＡＡ０．２ｍｇ／ｌ＋ＺＴ０．８ｍｌ／ｌ培养基中继代１～２次，形成了大量胚状体。胚状体经过球形胚、心形胚、鱼雷胚和子叶胚最终发育成再生植株。器官发生和体细胞胚胎发生这两种形态发生方式在发生顺序、形态特征和所需激素条件等方面都是不同的。     

泡桐体细胞胚胎发生过程中过氧化物酶的变化

以毛泡桐、兰考泡桐和白花泡桐的叶片为外植体进行体细胞胚胎发生的诱导,探讨体胚发生过程中过氧化物酶同工酶的变化.结果表明,在兰考泡桐、白花泡桐和毛泡桐叶片体细胞胚胎发生过程中,均有4种过氧化物同工酶稳定出现在体胚发生的不同时期,反映出在泡桐体细胞胚胎发生过程中对这些酶的需求是稳定的.这些稳定出现的酶可能是维持细胞代谢的一些基因表达的产物.而其它种类的同工酶在体细胞胚发生的不同阶段出现或消失,有可能作为体细胞胚胎发生的标志酶.     

关于一品红的胚囊类型的研究

一品红（E。Pho汕laP。Iclre，八ma）为大我科大如属植物，因其开花时具有红色的苞片而为著名的观赏植物。有关其胚囊发育类型到目前为止仍存有异议。因此，对一品红的雌配子体发育过程进行研究是必要的。1材料与方法一品红（EPulche，，ima）的供试材料为1994年12月取于华南植物研究所。取材时依于房大小而固定。固定液为FAA，实验方法为石蜡切片法，切片厚度8～10Pm，采用铁研—一苏木精染色，固绿复染，并制成永久封片。olymPusBH－2型研究显微镜上观察并照相。2观察结果一品红（E·Pulche，，ima）子房三室，每室1故胚珠，胚珠倒…     

金针菜的大孢子发生及雌配子体发育

金针菜的孢原细胞在花蕾长０．５ｃｍ左右时形成，孢原细胞直接发育为大孢子母细胞。胚珠薄珠心，蓼型胚囊。开花前，胚囊的变化是：卵细胞中具很多大淀粉粒，卵细胞和助细胞的合点端壁未完全消失；助细胞的丝状器在不同发育时期形态及大小不同；极核融合为次生核；反足细胞较早退化．对大孢子发生期间胼胝质壁的动态变化及胚囊发育中液泡的变化等进行不探讨。     

蓝盆花属的两种植物胚囊发育的比较研究

本文通过对华北蓝盆花和大花蓝盆花的胚囊发育及其他方面的比较研究,认为前者是一个物种,后者是前者的变种.     

Detection of CD2 expression in chicken hematogenic embryo yolk sac lymphoid cells prior to thymus genesis

Lymphoid mononuclear cells from chick embryos at stage 16 were collected prior to fetal liver and thymus genesis to study the differentiation and function of the hematogenic yolk sac and to detect whether CD2 occurs on the surface of lymphoid mononuclear cells. The phenotype and functional activity of the cell surface protein E receptor and the ultrastructure of embryonic E＋ cells were compared with those of mature T cells. Our results indicate 99.36% homology between the E receptors of embryonic lymphocytes and mature T cells. Other similarities, including molecular distribution, motivation, the ability to form an erythrocyte rosette, the structure of the receptor-ligand complex, and the conformation of the signal channel, were detected between embryonic lymphocytes and mature CD2-expressing T cells. These results indicate that CD2 is already expressed prior to fetal liver and thymus genesis and that its expression is not dependent on the thymic microenvironment.     

Positional variation of antipodal cells in polyembryonic rice ApⅢ before and after fertilization

The variation in the position of antipodal cells before and after fertilization in polyembryonic rice strain ApⅢ was studied by using conventional sectioning technique. It was shown that initially the three antipodal cells lie at the chalazal end of the young embryo sacs. Along with the development of embryo sac, the antipodal cells proliferate into a multicellular structure containing up to about 20 cells. Most of the cells migrate to its dorsal side when the embryo sacs turn into mature. In a few embryo sacs the antipodal cells are situated in the positions adjacent to the egg apparatus at the micropylar end, while in other sacs, they spread from the midst of the embryo sac to the micropylar end clinging to the nucellar tissue. Furthermore, it is reported for the first time that cells of some egg apparatus or proembryos disorganize when antipodal cells lie at the micropylar end, indicating that the function of the antipodal cells may vary during the embryogenesis in rice ApⅢ.     

Identification of an S5n allele in Oryza rufipogon Griff. and its effect on embryo sac fertility

Oryza rufipogon exhibits abundant genetic diversity and contains many elite genes. In this work, a total of 441 accessions of O. rufipogon were genetically examined using the functional marker S5n, revealing that 18 accessions carried the S5n allele with a heterozygous genotype (S5nS5i/j). Of these accessions, 14 were from Guangdong Province, 2 from Guangxi Zhuang Autonomous Region, 1 from Hainan Province and 1 from Jiangxi Province. Further sequence analysis spanning both sides of the deletion in S5n allel...     

基于工作流的管理系统开发模型

工作流技术是实现企业过程自动化的核心技术,成为当今计算机技术领域中重要的研究方向.对工作流管理系统的体系结构和工作流管理联盟提出的工作流参考模型进行了分析和总结,在此基础上,给出了工作流管理系统过程模型的建立过程,并对实际的工作流管理系统组织模型进行了设计.     

二元关系胚的性质及二元关系的胚分解

对于非空集合上的二元关系引入了关系的自反胚、反自反胚、对称胚、反对称胚、等价胚和偏序胚,并讨论了它们的基本性质,得到关系的3个唯一的基本胚分解式.     

不同洗眼液对结膜囊冲洗效果的影响

目的:探讨用两种洗眼液进行结膜囊冲洗(简称洗眼)对眼部的影响效果。方法:将492人分为两组进行洗眼:A组304人用生理盐水进行洗眼2次;B组188人用蒸馏水进行洗眼2次,了解洗眼后的眼部不适和结膜充血情况。结果:两组间眼部不适和结膜充血有显著性。结论:用生理盐水洗眼较用蒸馏水洗眼可减轻眼部不适及结膜充血。     

A guided tour: Pollen tube orientation in flowering plants

Sexual reproduction in flowering plants requires that two sperm cells are delivered to the embryo sac where double fertilization of an egg cell and of a central cell results in the formation of a diploid embryo and of the triploid nutritional endosperm tissue. The immobile male gametes are delivered to the im- mobile female gametophyte by a single cell, the pollen tube. The pollen tube must be able to germinate on a genetically appropriate stigma and it must be directed through the transmitting tract of the style from where it must target an ovule. Moreover, the pollen tube must enter the ovule at a defined opening, the micropyle, grow toward one of the two synergids and release the two sperm cells upon contact. This complex process requires recognition events with chemically based or physically supported cell-cell communication as well as directional cues for the growing pollen tube. A number of molecules and mechanisms have been implicated in pollen tube guidance which are summarized in this review.     

国产试剂配制的培养液对小鼠早期胚胎培养效果的研究

本实验用 Whitten 的小鼠早期胚胎培养法验证了国产试剂配制培养液对小鼠早期胚胎体外培养的效果。实验表明,在用国产试剂配制的小鼠早期胚胎培养液中,2—细胞胚胎能正常发育到囊胚阶段。