SOD对紫外辐射受损的苏云金芽孢杆菌作用的研究

探讨了超氧化物歧化酶 (SOD)等自由基清除剂对苏云金芽孢杆菌紫外辐射的影响。结果表明 ,SOD、绞股蓝皂甙等自由基清除剂能够明显地提高紫外辐射损伤细胞的存活率 ,并且SOD的保护作用表现为防护与恢复两种不同的作用。又通过细胞电泳与琼脂糖凝胶电泳发现紫外辐射后其细胞膜及质粒DNA均受到了明显的损伤 ;SOD对细胞膜损伤有一定的恢复作用 ,而对DNA不表现恢复效应。由此认为 :紫外线对细胞膜及DNA均有损伤 ,SOD恢复作用的主要部位在细胞膜而不是DNA分子。为进一步确定SOD的作用以及利用自由基清除剂制备高效的Bt农药提供了理论基础。     

辽东栎木材解剖特征与物理-力学性质的关系

本文借助通径系数分析及主成分分析等统计方法,以五株产自山西中条山的辽东栎为试验材料,详细研究了木材解剖特征的内在关系以及解剖特征与物理—力学性质的关系。结果表明,“细胞特征”(纤维、导管尺寸及微纤丝角等)和“组织比量”(导管、纤维及薄壁组织比量)两个主因子基本反映并代表了木材的所有解剖特征,同时也是影响木材物理—力学性质的两个基本解剖因子。     

貉消化系统的组织学结构

本文对50只育成貉消化器官的组织学结构进行了报导,为了解貉的生理机能及貉的疾病防治提供了科学依据。     

某些因子对四株维氏固氮菌菌株合成海藻酸的影响

本试验结果表明:相同条件下,四株维氏网氮菌(Azotobacter vinelandii)中,以菌株N_(13)的发酵周期短(1～2天),海藻酸合成最大(5.82 g/L),产海藻酸活力强(活力系数为2.60);不同条件下,菌株N_(13)在所试菌龄内,海藻酸合成最均高于其他菌株,其一天菌龄的浓度高达5.45±0.43 g/L,不同发酸液的海藻酸合成最仅在pH 8.0时低于菌株14~#,尤以pH6.0时,高达8.61g/L.在旋转式摇床或往复式摇床上,亦以菌株N_(13)的海藻酸合成量最高(3.61±0.26 g/L和4.39±0.12 g/L),试验温度范围内,也以菌株N_(13)的海藻酸合成量最高,32℃时达到最大值(6.41 g/L),菌株N_(13)以2～8％(V/V)的接种量试验表明:旋转式摇床为2％,往复式摇床为2～4％。     

Advances on Plant Cell Engineering Technology Application in Rapeseed Breeding

综述了近20年来国内外利用植物细胞工程技术进行油菜育种所取得的成就。器官、组织和单细胞培养不仅可用于繁殖和保存种质,而且已用来诱导体细胞变异,产生突变体。花药、小孢子体系的建立,促进了单倍体育种的进行,加速了作物育种进程。子房、胚珠和胚培养以及体细胞杂交可用于克服远缘杂交的不亲和性和杂种的不育性,有利于拓宽种质资源。通过分析提出了在今后的油菜育种中,植物细胞工程技术将是一种重要的辅助育种手段。     

真菌分类技术的研究进展

综述了真菌分类研究中一些常用技术的变化和发展,并归纳和总结了这些技术的优缺点。     

鹿茸角软骨细胞体外培养方法的建立及生长特性分析

【研究目的】建立梅花鹿鹿茸软骨细胞体外分离培养和扩增方法,观察鹿茸软骨细胞在体外培养的生物学特性,为鹿茸再生机理的研究奠定基础;【方法】体外分离培养鹿茸软骨细胞,采用组织学、MTT比色法、免疫组化等多种手段动态检测细胞生长增殖情况;【结果】核心部分,约150字鹿茸软骨细胞贴壁生长,原代细胞比传代生长速度快,原代及传代4代内的鹿茸软骨细胞均有活跃的增殖能力,软骨细胞呈三角形,多边形等多种形态,II型胶原免疫组化,甲苯胺蓝染色为阳性;【结论】体外分离培养鹿茸软骨细胞具有较强的增殖能力,传代培养4代内细胞生长旺盛并维持其生物学特性,可满足后续实验研究要求。     

白平菇细胞工程菌株的耐热性研究

将通过原生质体再生技术制备的19株白平菇细胞工程菌株,分别在20、25、30和35 ℃中培养.结果表明,有6株细胞工程菌株表现出了比出发菌株较高的耐热能力,同时,所有的菌株在20、25和30 ℃下均能生长,而在35℃条件下菌丝只能萌发,不能生长.经进一步的耐热性菌株的筛选,选育出了一株较耐热的菌株P484.     

Experimental Researches on Carcinogenesis or Tumorigenicity of MDCK Canine Kidney Cell(CKC) Lines and Analysis of Their Chromosome Karyotypes

The chromosomal number variations & structural aberrations of the MDCK cell line, primary feline or canine kidney cell(FKC or CKC) and Hela cell line were investigated and their karyotypes of conventional chromosome bands were analyzed. The carcinogenesis or tumorigenicity testing of these cell lines in about 232 nude mice and for colony formation in soft agarose and for haemagglutination under different concentration of plant lectins of these cells were carried out. Under the prerequisite that the incidence of cancer or tumor in negative-control nude mice inoculated subcutaneously with primary feline or canine kidney cell cultures purified in vitro at passage 3 was 0 (0/22) and 0 (0/10), respectively. The incidence of the progressively-growing malignant tumor(MT) in positive-control nude mice inoculated subcutaneously with Hela cell cultures of KB, X, or NM20/X strain was 10/10, 25/25 and 5/51, respectively. The results showed that the incidence of tumor in nude mice with tetrapioid YA strain of MDCK cell during 20 - 45 passages, with hypodiploid JB strain of MDCK cell on passage 25, with di-and hypoploid JC strain of MDCK cell during 2 - 15passages or with hypoploid M strain of MDCK cell during 9 - 27 passages was 28/58, 1/5, 4/18 and 0/31,respectively. The chromosomal analysis results showed that the ratio of difference in the rate of modal chromosome number between high (mcs + n) and lowest (mcs)passages was not more than 5 % - 15 % and the structure aberrations was generally 0 - 3%. These results proved that the genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species-specific. MDCK line has tumorigenicity no matter what its chromosome karyotype is, at least it has very low tumorigenicity even when its modal chromosome number is hypoploid. The repeatedly frozen, thawed and split controls of tumorigenicity-positive cell lines(X strain of Hela, M strain of BHK-21, JA strain of Vero, YA strain of MDCK) have much lower tumorigenicity or are even non-carcinogenesis, and the repeatedly frozen, thawed and split controls of very low tumorigenicity cell lines (M or JC strain of MDCK) are certainly non-carcinogenic and never have increased tumorigenicity.It is thus evident that MDCK cell of M, JB or JC strain can be approved as substrate for the preparation of attenuated viral vaccines, but MDCK cell of YA strain can not be approved as substrate for the preparation of comattenuated viral vaccines. In summary, all strains of MDCK cell line have tunorigenicity, at least have low tumorigencity, never have non-cancinogenic MDCK, but very low tumorigenicity MDCK cell strains can certainly be used for the approval production of canine viral vaccines if the DNA content in viral cell cultures was remarkably decreased through conventional means in manufacturing process. Therefore, the master cell stock and working cell bank of MDCK line used for vaccine manufacture were established in China, which are free of infectious agents, and described with respect to cytogenetic characteristics and tumorigenicity. Tests showed that there were correlations among cell line chromosome number variations, anchorage independence in soft agarose, haemagglutination under plant lectins, and tumor-forming ability in nude mice, thus all the in vitro tests are economic, simple and reliable means for monitoring the tumor-forming ability of MDCK line in nude mice.     

香菇细胞融合育种的预备研究——原生质体制备与再生

探讨了在森林资源综合利用中具重要意义的木腐性食用菌香菇(Lentinus edodes)的原生质体制备及再生条件。对用MYG培养的菌丝,采用以0.6mol甘露醇为稳渗剂的1.5％溶壁酶Lywallzyme进行酶解脱壁,在菌龄7d、酶解液pH值4.5、温度28℃、酶解4h时原生质体产量最高(6×10~6/ml,每0.1g鲜菌丝)。酶解温度>31℃时原生质体产量和再生率都明显降低。用SO培养基代替MYG可使原生质体产量提高1倍,但再生率显著下降(从8.5％下降到1.1％)。从产量和再生率两方面综合考虑,以MYG作为菌丝培养基效果较好。