用细胞遗传学方法研究生化灭鼠剂对哺乳动物体细胞的…

经人外周血淋巴细胞姊妹染色单体互换，小鼠骨髓细胞的染色体畸变分析，以及致哺乳动物的嗜多染红细胞的微核发生试验、研究了不同性质的生化灭鼠剂对人和小鼠体内细胞的致突变性。结果表明，无论生化灭鼠剂是否具生理毒性，对人和小白鼠体细胞均不具致突变性。     

三硝基甲苯的致突变性研究

利用三硝基甲苯对小鼠致突变作用进行了研究．实验结果表明，该药物在一定浓度下，对小鼠体细胞和生殖细胞均有较强的致突变性．本实验可为三硝基甲苯远期毒性效应的研究和安全性评价提供科学依据．     

氯乙烯对小鼠致突变性的实验研究

为了进一步研究在不同剂量下氯乙烯对人等哺乳动物体细胞和生殖细胞的诱变性．从而在其工业生产过程中最大程度地降低其毒性，进行了研究。通过小鼠骨髓微核试验和精子畸形试验的方法，分别获得氯乙烯致微核率和精于畸形率，进而对氯乙烯的致突变性进行研究。表明氯乙烯有致突变作用，氯乙烯为潜在的精于诱变剂。     

交通性污染物致小鼠突变性的研究

以清洁级ICR小白鼠为实验动物,研究温州市区交通污染物对小鼠的致突变性。选择温州鹿城区望江路防空洞为处理现场,采用小鼠骨髓嗜多染红细胞(PCE)的微核试验以及小鼠精子畸形试验等方法。结果显示小鼠PCE的微核率、精子畸形率均为防空洞的>望江路的>对照组;而精子密度、精子活力以及睾丸重量则为防空洞的<望江路的<对照组。结论:交通性污染物对小鼠体细胞及生殖细胞均有明显致突变作用。     

制革厂生产废水有机提取物的致突变性研究

目的了解制革厂污水处理状况，以采取相应的控制对策。方法对东莞市某制革厂生产用水、生产废水和已处理水进行了有机浓集物对小鼠的的致突变性研究，进行了小鼠骨髓细胞微核试验和小鼠精子畸变试验。结果制革厂的生产用水在用于生产之前已受到致突变性污染。结论致突变性从大到小依次为生产废水、已处理水、生产用水。     

昆虫病毒对脊椎动物体细胞的致突变性研究

用微核测定法,检测3种昆虫病毒包涵体及其降解物对小白鼠骨髓多染红细胞染色体的损伤程度。证明对脊椎动物体细胞是否具有致突变性。结果表明,3种昆虫病毒对小白鼠骨髓嗜多染红细胞没有损伤作用。可以认为3种昆虫病毒对哺乳动物体细胞无致突变作用。     

甲基叔丁基醚、无水乙醇、碳酸二甲酯的致突变性

评价和比较了3种汽油增氧剂甲基叔丁基醚(MTBE)、无水乙醇(AE)和碳酸二甲酯(DMC)的致突变性.采用Ames实验研究3种汽油增氧剂的致突变性;采用小鼠睾丸染色体畸变实验检测3种汽油增氧剂对小鼠睾丸染色体的致畸作用.Ames实验的阴性结果表明,在本实验条件下,未发现MTBE、AE、DMC具有致突变性.在小鼠睾丸染色体畸变实验中,虽然实验结果为阴性,但随着MTBE剂量的增加,染色体分离有增加趋势,表明其可能存在遗传毒性.     

多菇口服液毒理安全性实验研究

目的检测多菇口服液作为保健食品的安全性。方法通过小鼠经口急性毒性试验、致突变试验,大鼠30d喂养试验对多菇口服液进行检测。结果小鼠经口LD50>21.5g/kg,属无毒级物质;致突变试验结果为阴性;大鼠30d喂养试验表明各剂量组体重增长、食物利用率、脏体比、血液学及血清生化指标与对照组比较均无显着性差异(P>0.05)。病理检查主要脏器未发现与实验有关的病理性改变。结论多菇口服液为无毒、无致突变作用的保健食品。     

新氨基酸螯合钙制剂L-亮氨酸钙的急性毒性及致突变性

研究自制的新型氨基酸螯合钙制剂--L-亮氨酸钙的急性毒性及致突变性,并对其安全性进行评价.对小鼠分别给予不同质量的L-亮氨酸钙混悬液灌胃, 连续7 d观察小鼠急性毒性.将50只小鼠随机分为5组:阴性对照组、质量比为0.04 g·kg-1的环磷酰胺组,以及质量比分别为0.5,2.5,5.0 g·kg-1的L-亮氨酸钙混悬液组通过染色体畸变试验、小鼠骨髓嗜多染红细胞微核试验和小鼠精子畸形试验,观察L-亮氨酸钙的遗传毒性.结果表明,为小鼠灌胃7 d后半数致死计量(LD50)大于10 g ·kg-1,L-亮氨酸钙属实际无毒物质在染色体畸变试验、小鼠骨髓嗜多染红细胞微核试验和小鼠精子畸形试验中均呈阴性反应,未显示致突变作用,表明L-亮氨酸钙无毒性和无致突变性.     

骨营养素安全性毒理学实验研究

目的检测骨营养素作为保健食品的安全性。方法依据卫生部《保健食品检验与评价技术规范》,通过小鼠经口急性毒性试验、致突变试验,大鼠30 d喂养试验对骨营养素进行检测。结果小鼠经口LD50>21.5 g/kg,属无毒级物质;致突变试验结果为阴性;大鼠30 d喂养试验表明,各剂量组体重增长、食物利用率、脏体比、血液学及血清生化指标与对照组比较均无显着性差异(P>0.05),通过病理检查,主要脏器未发现与实验有关的病变。结论骨营养素为无毒、无致突变作用的保健食品。     

Horizontal cell synapses onto glycine-accumulating interplexiform cells

Horizontal cells mediate lateral transmission of signals in the outer plexiform layer of the vertebrate retina, and are presumed to contribute to surround properties of photoreceptors and bipolar cells by chemical transmission. The cell bodies and dendrites of fish horizontal cells possess presynaptic specializations characteristic of conventional chemical synapses. Horizontal cell axon terminals have not so far been shown to contain presynaptic specializations nor have the targets of the somatic and dendritic synapses been fully characterized. Using electron microscope autoradiography of retinas labelled by high-affinity 3H-glycine uptake, we show here that goldfish horizontal cells make somatodendritic and axodendritic synapses on glycinergic interplexiform cells (Gly-IPCs) as apposed to dopaminergic interplexiform cells. Thus, horizontal cells have at least three postsynaptic targets: photoreceptors, bipolar cells and Gly-IPCs. Gly-IPCs may constitute a major alternative pathway for horizontal cell signals to reach the inner plexiform layer.     

花卉体细胞胚胎发生研究进展

综述花卉体细胞胚胎发生途径、体细胞胚胎发生过程的生理生化变化及其影响因素、体细胞胚胎发生与胚性基因的表达和花卉体细胞无性系变异等方面的研究进展,植物体细胞胚胎发生研究在基因工程体细胞融合、细胞突变体诱导、人工种子、杂种合子胚的挽救、种质保存、苗木快速繁殖等诸多方面有着广阔的应用前景,也是遗传学、转基因工程体系、生理生化、植物发育过程的基因表达和调控、功能基因组研究等方面一个必不可少的新兴研究系统.     

植物细胞工程进展

概要介绍了植物细胞工程的主要分支学科及其研究进展。包括原生质体培养、细胞融合与体细胞杂交、胚胎培养和试管受精、组织和细胞培养生产有用物质、单倍体育种、体细胞无性系变异、细胞突变体的筛选、植物快速繁殖技术、体细胞胚胎发生和人工种子、组织细胞培养物的超低温保存以及转基因植物等。     

p63 protects the female germ line during meiotic arrest

Meiosis in the female germ line of mammals is distinguished by a prolonged arrest in prophase of meiosis I between homologous chromosome recombination and ovulation. How DNA damage is detected in these arrested oocytes is poorly understood, but it is variably thought to involve p53, a central tumour suppressor in mammals. While the function of p53 in monitoring the genome of somatic cells is clear, a consensus for the importance of p53 for germ line integrity has yet to emerge. Here we show that the p53 homologue p63 (refs 5, 6), and specifically the TAp63 isoform, is constitutively expressed in female germ cells during meiotic arrest and is essential in a process of DNA damage-induced oocyte death not involving p53. We also show that DNA damage induces both the phosphorylation of p63 and its binding to p53 cognate DNA sites and that these events are linked to oocyte death. Our data support a model whereby p63 is the primordial member of the p53 family and acts in a conserved process of monitoring the integrity of the female germ line, whereas the functions of p53 are restricted to vertebrate somatic cells for tumour suppression. These findings have implications for understanding female germ line fidelity, the regulation of fertility and the evolution of tumour suppressor mechanisms.     

伊贝母体细胞胚和器官发生几种大分子活性的比较研究

本文报道了伊贝母组织培养中体细胞胚发生和器官发生过程中的核酸、蛋白质含量及过氧化物酶活性动态的变化。共同特点是，培养初期几种大分子物质的含量均呈显著上升的趋势。说明两种途径均伴随着大分子物质的迅速合成。以后随着形态建成的进程，也都呈现相似的趋势。而ＲＮＡ和蛋白的合成总是先于ＤＮＡ的合成，说明这几种大分子的动态变化具有顺序性。其区别在于，体细胞胚胎发生过程几种大分子的活性高于器官发生过程，前者是一个     

脊椎动物染色体数目及其变化趋势

收集了２９７８种脊椎动物的染色体数目，论述了各纲内动物染色体数目变化的趋势及规律，对从染色本水平上认识脊椎动物的进化有参考价值。     

Migratory neural crest-like cells form body pigmentation in a urochordate embryo

The neural crest, a source of many different cell types in vertebrate embryos, has not been identified in other chordates. Current opinion therefore holds that neural crest cells were a vertebrate innovation. Here we describe a migratory cell population resembling neural crest cells in the ascidian urochordate Ecteinascidia turbinata. Labelling of embryos and larvae with the vital lipophilic dye DiI enabled us to detect cells that emerge from the neural tube, migrate into the body wall and siphon primordia, and subsequently differentiate as pigment cells. These cells express HNK-1 antigen and Zic gene markers of vertebrate neural crest cells. The results suggest that migratory cells with some of the features of neural crest cells are present in the urochordates. Thus, we propose a hypothesis for neural crest evolution beginning with the release of migratory cells from the CNS to produce body pigmentation in the common ancestor of the urochordates and vertebrates. These cells may have gained additional functions or were joined by other cell types to generate the variety of derivatives typical of the vertebrate neural crest.