根霉超氧化物歧化酶同工酶类型的鉴别

利用ＫＣＮ、Ｈ_２Ｏ２和ＳＤＳ的选择性反应引起的ＳＯＤ同工酶谱带变化即可鉴别粗抽提液中的ＳＯＤ同工酶类型;用这种方法对五株不同种根霉的鉴别实验表明,它们均不同程度地含有Ｃｕ,Ｚｎ型和Ｍｎ型两种ＳＯＤ,前者约占８０％左右,后者只占２０％左右。用邻苯三酚自氧化法对样品中ＳＯＤ活性测定结果与在同工酶谱上的鉴别结果基本一致。     

耳时蝉属四新种（同翅目：耳叶蝉科）

本文记述耳叶蝉科耳叶蝉属四新种：１．浅斑耳叶蝉Ｌｅｄｒａｐａｌｌｉｄｅｓｐ．ｎｏｖ,２．片脊耳叶蝉Ｌｅｄｒａｌａｍｅｌｌａｓｐ．ｎｏｖ,３．黑纹耳叶蝉Ｌｅｄｒａｎｉｇｒｏｌｉｎｅａｔａｓｐ．ｎｏｖ,４．明冠耳叶蝉Ｌｅｄｒａｈｙａｌｉｎａｓｐ．ｎｏｖ．．标本分别采自我国西藏、云南及安徽省．模式标本保存于安徽农学院．     

RFLP诊断方法的改进

RFLP(限制性片段长度多态)技术应用于遗传病的诊断始于1981年。在十年时间里,这一基因诊断技术和分析方法不断得到发展和改进。随着越来越多的致病基因和连锁DNA多态片段的分离和克隆,该技术在分析缺陷基因性质,携带者检出和产前诊断等方面将发挥重要作用.然而,RFLP技术复杂,耗费时间和费用较大,使其向临床推广应用面临很大局限性。因此,基因诊断的方法简化和技术改进大有必要。1985年首创的多聚酶链     

鸡马立克氏病病毒B抗原片段在大肠杆菌中表达

鸡马立克氏病病毒ＢａｍＨＩ基因文库Ｉ３质粒中含有编码Ｂ抗原膜外Ｄｏｍａｉｎ的ＤＮＡ序列。经ＳｃａＩ和ＳｐｈＩ双酶酶解Ｉ３质粒,分离获得７６４ｂｐＤＮＡ片段,并克隆进Ｍ１３ｍｐ１９中。ＤＮＡ序列测定分析表明克隆片段为ＭＤＶ－Ｂ抗原基因的４９４－１２５８ｂｐ部分序列。进一步分离ＮｃｏＩ－ＨｉｎｄＩＩＩ部分基因片（５３０ｂｐ）,克隆于ＰＬＰｒｏｍｏｔｅｒ控制下的含有修饰型ｃＩｔｓ８５７基因的表达载体中,     

Cytogenetic study of mentally retarded children in Taipei

560 blood samples collected from mentally retarded children in Taipei were karyotypically analyzed for the incidence of fragile X and other chromosome abnormalities. The fragile site at Xq27.3 was observed in 18 patients (3.21%), 11 males and 7 females, out of the 560 blood cultures using M medium. Down syndrome (6.25%), 24 males and 11 females, was the other major category of abnormality. Other abnormalities, including inversion, translocation, deletion, duplication, ring as well as an extra marker chromosome were observed. The overall incidence of chromosomal abnormalities in these children was 14.82%.     

Morphological Response of Witchweed (Striga asiatica) to In Vitro Culture

Excised sorghum root segments (5–10 mm in length) werecultured for 50 d in four different liquid media containingmineral salts, vitamins, amino acids, glucose, and IAA. Theroots were removed and the remaining medium was solidified withan equal volume of warm 1–6% water agar. Dry unconditionedor conditioned Striga asiatica seeds were transferred to themedium. Some of the seeds germinated and developed into parasitic-typeseedlings. These seedlings had haustoria, tubercles, dense roothairs, branched shoots, and multiple shoot-borne adventitiousroots. The plumule pole developed into a shoot, but the radiclepole displayed only rudimentary development. On the same media,but which had not previously been used to grow sorghum roots,the seedlings displayed a well-developed radicle-derived rootsystem, but the plumule did not grow. Shoots began to appearon the roots only after 35–50 d of culture. These seedlingshad no haustoria, no tubercles, few or scattered root hairs,no shoot-borne adventitious roots and few shoot branches, andappeared to be non-parasitic-type seedlings. Shoots grew ina medium supplemented with IAA and kinetin, but did not in amedium containing NAA plus IBA. On replacement of glucose andIAA with sucrose and 2,4-D, respectively, Striga seeds germinated,and the heart-shaped embryos dedifferentiated into calli. Thecalli have been maintained by subculturing for over 9 months.The results demonstrated that a host signal, in addition tothose for germination and haustorium formation, is requiredfor further development. Moreover, morphogenesis of culturedS. asiatica is influenced by exogenous growth regulators. Key words: Striga asiatica, parasitic weeds, haustoria, Sorghum bicolor, in vitro culture     

中国十个地理品系卤虫同工酶的研究

本文采用聚丙烯酰胺凝胶垂直板电泳法,对中国十个不同地理品系卤虫的十种同工酶进行了研究。分析了编码七种多态酶的19个座位、42个等位基因,用Nei(1972、1975)的方法计算各地理品系卤虫的遗传相似系数、遗传距离和平均杂合度并进行聚类分析。实验和分析结果证明十个不同地理品系的卤虫可分为A.parthenogenetica和有性品系A.sp.两大姊妹种;十种同工酶中三种酶为单态酶,七种为多态酶;雌雄个体无电泳差异。     

基于肠道微生态改善的益生菌抗糖尿病作用机制研究进展

2型糖尿病(type 2 diabetes, T2D)会引起糖脂代谢紊乱,严重危害人类健康,为了防治这一流行病,急需寻找安全和无副作用的抗糖尿病的方法,其中,基于微生物方法治疗T2D最常见的策略是补充益生菌,其可通过对不同组织和代谢通路的调节来实现抗糖尿病的功效。益生菌摄入可通过降低慢性低度炎症,减少氧化应激,调节肠道菌群,增加短链脂肪酸含量来达到调控血糖的目的;通过增加胆固醇与胆盐的共沉淀作用,胆固醇在胃肠道内转化为粪甾醇,降低肝脏中3-羟基-3-甲基戊二酸单酰辅酶A还原酶活性,降低胆固醇转运体的表达及对脂肪细胞的调节来达到降脂的目的。本综述系统总结了益生菌抗糖尿病现状和基于肠道微生态的抗糖尿病分子机制,以期为益生菌作为降糖降脂等保健产品的开发利用提供理论依据。     

长窦副新蚤雄蚤的形态记述(蚤目:多毛蚤科)

本文首次记述了采自青海玉树的长窦副新蚤Paraneopsylla longisinuata Liu, Tsai & Wu,1974的雄蚤。模式标本保存于著者所在的单位。     

羊奶果根瘤内生菌的亚显微结构

羊奶果是桤木型根瘤。根瘤的横切面是轴对称的圆形结构,含菌细胞分散于皮层组织中。随着根瘤的发育,内生菌也有不同的形态结构。侵染初期的内生菌是一种分枝、具隔膜的菌丝体。幼龄菌丝中含有电子半透明的颗粒,成熟菌丝没有这种颗粒。成熟菌丝顶端会臌大形成具隔膜的椭圆球状泡囊,直径比菌丝大。不同发育时期的泡囊,其形态结构也有差异。